diff options
Diffstat (limited to 'drivers/webp/enc')
| -rw-r--r-- | drivers/webp/enc/delta_palettization.c | 455 | ||||
| -rw-r--r-- | drivers/webp/enc/delta_palettization.h | 25 | ||||
| -rw-r--r-- | drivers/webp/enc/near_lossless.c | 160 | ||||
| -rw-r--r-- | drivers/webp/enc/picture_csp.c | 1156 | ||||
| -rw-r--r-- | drivers/webp/enc/picture_psnr.c | 175 | ||||
| -rw-r--r-- | drivers/webp/enc/picture_rescale.c | 264 | ||||
| -rw-r--r-- | drivers/webp/enc/picture_tools.c | 206 | ||||
| -rw-r--r-- | drivers/webp/enc/token.c | 285 |
8 files changed, 2726 insertions, 0 deletions
diff --git a/drivers/webp/enc/delta_palettization.c b/drivers/webp/enc/delta_palettization.c new file mode 100644 index 0000000000..062e588d79 --- /dev/null +++ b/drivers/webp/enc/delta_palettization.c @@ -0,0 +1,455 @@ +// Copyright 2015 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// Author: Mislav Bradac (mislavm@google.com) +// + +#include "./delta_palettization.h" + +#ifdef WEBP_EXPERIMENTAL_FEATURES +#include "../webp/types.h" +#include "../dsp/lossless.h" + +#define MK_COL(r, g, b) (((r) << 16) + ((g) << 8) + (b)) + +// Format allows palette up to 256 entries, but more palette entries produce +// bigger entropy. In the future it will probably be useful to add more entries +// that are far from the origin of the palette or choose remaining entries +// dynamically. +#define DELTA_PALETTE_SIZE 226 + +// Palette used for delta_palettization. Entries are roughly sorted by distance +// of their signed equivalents from the origin. +static const uint32_t kDeltaPalette[DELTA_PALETTE_SIZE] = { + MK_COL(0u, 0u, 0u), + MK_COL(255u, 255u, 255u), + MK_COL(1u, 1u, 1u), + MK_COL(254u, 254u, 254u), + MK_COL(2u, 2u, 2u), + MK_COL(4u, 4u, 4u), + MK_COL(252u, 252u, 252u), + MK_COL(250u, 0u, 0u), + MK_COL(0u, 250u, 0u), + MK_COL(0u, 0u, 250u), + MK_COL(6u, 0u, 0u), + MK_COL(0u, 6u, 0u), + MK_COL(0u, 0u, 6u), + MK_COL(0u, 0u, 248u), + MK_COL(0u, 0u, 8u), + MK_COL(0u, 248u, 0u), + MK_COL(0u, 248u, 248u), + MK_COL(0u, 248u, 8u), + MK_COL(0u, 8u, 0u), + MK_COL(0u, 8u, 248u), + MK_COL(0u, 8u, 8u), + MK_COL(8u, 8u, 8u), + MK_COL(248u, 0u, 0u), + MK_COL(248u, 0u, 248u), + MK_COL(248u, 0u, 8u), + MK_COL(248u, 248u, 0u), + MK_COL(248u, 8u, 0u), + MK_COL(8u, 0u, 0u), + MK_COL(8u, 0u, 248u), + MK_COL(8u, 0u, 8u), + MK_COL(8u, 248u, 0u), + MK_COL(8u, 8u, 0u), + MK_COL(23u, 23u, 23u), + MK_COL(13u, 13u, 13u), + MK_COL(232u, 232u, 232u), + MK_COL(244u, 244u, 244u), + MK_COL(245u, 245u, 250u), + MK_COL(50u, 50u, 50u), + MK_COL(204u, 204u, 204u), + MK_COL(236u, 236u, 236u), + MK_COL(16u, 16u, 16u), + MK_COL(240u, 16u, 16u), + MK_COL(16u, 240u, 16u), + MK_COL(240u, 240u, 16u), + MK_COL(16u, 16u, 240u), + MK_COL(240u, 16u, 240u), + MK_COL(16u, 240u, 240u), + MK_COL(240u, 240u, 240u), + MK_COL(0u, 0u, 232u), + MK_COL(0u, 232u, 0u), + MK_COL(232u, 0u, 0u), + MK_COL(0u, 0u, 24u), + MK_COL(0u, 24u, 0u), + MK_COL(24u, 0u, 0u), + MK_COL(32u, 32u, 32u), + MK_COL(224u, 32u, 32u), + MK_COL(32u, 224u, 32u), + MK_COL(224u, 224u, 32u), + MK_COL(32u, 32u, 224u), + MK_COL(224u, 32u, 224u), + MK_COL(32u, 224u, 224u), + MK_COL(224u, 224u, 224u), + MK_COL(0u, 0u, 176u), + MK_COL(0u, 0u, 80u), + MK_COL(0u, 176u, 0u), + MK_COL(0u, 176u, 176u), + MK_COL(0u, 176u, 80u), + MK_COL(0u, 80u, 0u), + MK_COL(0u, 80u, 176u), + MK_COL(0u, 80u, 80u), + MK_COL(176u, 0u, 0u), + MK_COL(176u, 0u, 176u), + MK_COL(176u, 0u, 80u), + MK_COL(176u, 176u, 0u), + MK_COL(176u, 80u, 0u), + MK_COL(80u, 0u, 0u), + MK_COL(80u, 0u, 176u), + MK_COL(80u, 0u, 80u), + MK_COL(80u, 176u, 0u), + MK_COL(80u, 80u, 0u), + MK_COL(0u, 0u, 152u), + MK_COL(0u, 0u, 104u), + MK_COL(0u, 152u, 0u), + MK_COL(0u, 152u, 152u), + MK_COL(0u, 152u, 104u), + MK_COL(0u, 104u, 0u), + MK_COL(0u, 104u, 152u), + MK_COL(0u, 104u, 104u), + MK_COL(152u, 0u, 0u), + MK_COL(152u, 0u, 152u), + MK_COL(152u, 0u, 104u), + MK_COL(152u, 152u, 0u), + MK_COL(152u, 104u, 0u), + MK_COL(104u, 0u, 0u), + MK_COL(104u, 0u, 152u), + MK_COL(104u, 0u, 104u), + MK_COL(104u, 152u, 0u), + MK_COL(104u, 104u, 0u), + MK_COL(216u, 216u, 216u), + MK_COL(216u, 216u, 40u), + MK_COL(216u, 216u, 176u), + MK_COL(216u, 216u, 80u), + MK_COL(216u, 40u, 216u), + MK_COL(216u, 40u, 40u), + MK_COL(216u, 40u, 176u), + MK_COL(216u, 40u, 80u), + MK_COL(216u, 176u, 216u), + MK_COL(216u, 176u, 40u), + MK_COL(216u, 176u, 176u), + MK_COL(216u, 176u, 80u), + MK_COL(216u, 80u, 216u), + MK_COL(216u, 80u, 40u), + MK_COL(216u, 80u, 176u), + MK_COL(216u, 80u, 80u), + MK_COL(40u, 216u, 216u), + MK_COL(40u, 216u, 40u), + MK_COL(40u, 216u, 176u), + MK_COL(40u, 216u, 80u), + MK_COL(40u, 40u, 216u), + MK_COL(40u, 40u, 40u), + MK_COL(40u, 40u, 176u), + MK_COL(40u, 40u, 80u), + MK_COL(40u, 176u, 216u), + MK_COL(40u, 176u, 40u), + MK_COL(40u, 176u, 176u), + MK_COL(40u, 176u, 80u), + MK_COL(40u, 80u, 216u), + MK_COL(40u, 80u, 40u), + MK_COL(40u, 80u, 176u), + MK_COL(40u, 80u, 80u), + MK_COL(80u, 216u, 216u), + MK_COL(80u, 216u, 40u), + MK_COL(80u, 216u, 176u), + MK_COL(80u, 216u, 80u), + MK_COL(80u, 40u, 216u), + MK_COL(80u, 40u, 40u), + MK_COL(80u, 40u, 176u), + MK_COL(80u, 40u, 80u), + MK_COL(80u, 176u, 216u), + MK_COL(80u, 176u, 40u), + MK_COL(80u, 176u, 176u), + MK_COL(80u, 176u, 80u), + MK_COL(80u, 80u, 216u), + MK_COL(80u, 80u, 40u), + MK_COL(80u, 80u, 176u), + MK_COL(80u, 80u, 80u), + MK_COL(0u, 0u, 192u), + MK_COL(0u, 0u, 64u), + MK_COL(0u, 0u, 128u), + MK_COL(0u, 192u, 0u), + MK_COL(0u, 192u, 192u), + MK_COL(0u, 192u, 64u), + MK_COL(0u, 192u, 128u), + MK_COL(0u, 64u, 0u), + MK_COL(0u, 64u, 192u), + MK_COL(0u, 64u, 64u), + MK_COL(0u, 64u, 128u), + MK_COL(0u, 128u, 0u), + MK_COL(0u, 128u, 192u), + MK_COL(0u, 128u, 64u), + MK_COL(0u, 128u, 128u), + MK_COL(176u, 216u, 216u), + MK_COL(176u, 216u, 40u), + MK_COL(176u, 216u, 176u), + MK_COL(176u, 216u, 80u), + MK_COL(176u, 40u, 216u), + MK_COL(176u, 40u, 40u), + MK_COL(176u, 40u, 176u), + MK_COL(176u, 40u, 80u), + MK_COL(176u, 176u, 216u), + MK_COL(176u, 176u, 40u), + MK_COL(176u, 176u, 176u), + MK_COL(176u, 176u, 80u), + MK_COL(176u, 80u, 216u), + MK_COL(176u, 80u, 40u), + MK_COL(176u, 80u, 176u), + MK_COL(176u, 80u, 80u), + MK_COL(192u, 0u, 0u), + MK_COL(192u, 0u, 192u), + MK_COL(192u, 0u, 64u), + MK_COL(192u, 0u, 128u), + MK_COL(192u, 192u, 0u), + MK_COL(192u, 192u, 192u), + MK_COL(192u, 192u, 64u), + MK_COL(192u, 192u, 128u), + MK_COL(192u, 64u, 0u), + MK_COL(192u, 64u, 192u), + MK_COL(192u, 64u, 64u), + MK_COL(192u, 64u, 128u), + MK_COL(192u, 128u, 0u), + MK_COL(192u, 128u, 192u), + MK_COL(192u, 128u, 64u), + MK_COL(192u, 128u, 128u), + MK_COL(64u, 0u, 0u), + MK_COL(64u, 0u, 192u), + MK_COL(64u, 0u, 64u), + MK_COL(64u, 0u, 128u), + MK_COL(64u, 192u, 0u), + MK_COL(64u, 192u, 192u), + MK_COL(64u, 192u, 64u), + MK_COL(64u, 192u, 128u), + MK_COL(64u, 64u, 0u), + MK_COL(64u, 64u, 192u), + MK_COL(64u, 64u, 64u), + MK_COL(64u, 64u, 128u), + MK_COL(64u, 128u, 0u), + MK_COL(64u, 128u, 192u), + MK_COL(64u, 128u, 64u), + MK_COL(64u, 128u, 128u), + MK_COL(128u, 0u, 0u), + MK_COL(128u, 0u, 192u), + MK_COL(128u, 0u, 64u), + MK_COL(128u, 0u, 128u), + MK_COL(128u, 192u, 0u), + MK_COL(128u, 192u, 192u), + MK_COL(128u, 192u, 64u), + MK_COL(128u, 192u, 128u), + MK_COL(128u, 64u, 0u), + MK_COL(128u, 64u, 192u), + MK_COL(128u, 64u, 64u), + MK_COL(128u, 64u, 128u), + MK_COL(128u, 128u, 0u), + MK_COL(128u, 128u, 192u), + MK_COL(128u, 128u, 64u), + MK_COL(128u, 128u, 128u), +}; + +#undef MK_COL + +//------------------------------------------------------------------------------ +// TODO(skal): move the functions to dsp/lossless.c when the correct +// granularity is found. For now, we'll just copy-paste some useful bits +// here instead. + +// In-place sum of each component with mod 256. +static WEBP_INLINE void AddPixelsEq(uint32_t* a, uint32_t b) { + const uint32_t alpha_and_green = (*a & 0xff00ff00u) + (b & 0xff00ff00u); + const uint32_t red_and_blue = (*a & 0x00ff00ffu) + (b & 0x00ff00ffu); + *a = (alpha_and_green & 0xff00ff00u) | (red_and_blue & 0x00ff00ffu); +} + +static WEBP_INLINE uint32_t Clip255(uint32_t a) { + if (a < 256) { + return a; + } + // return 0, when a is a negative integer. + // return 255, when a is positive. + return ~a >> 24; +} + +// Delta palettization functions. +static WEBP_INLINE int Square(int x) { + return x * x; +} + +static WEBP_INLINE uint32_t Intensity(uint32_t a) { + return + 30 * ((a >> 16) & 0xff) + + 59 * ((a >> 8) & 0xff) + + 11 * ((a >> 0) & 0xff); +} + +static uint32_t CalcDist(uint32_t predicted_value, uint32_t actual_value, + uint32_t palette_entry) { + int i; + uint32_t distance = 0; + AddPixelsEq(&predicted_value, palette_entry); + for (i = 0; i < 32; i += 8) { + const int32_t av = (actual_value >> i) & 0xff; + const int32_t pv = (predicted_value >> i) & 0xff; + distance += Square(pv - av); + } + // We sum square of intensity difference with factor 10, but because Intensity + // returns 100 times real intensity we need to multiply differences of colors + // by 1000. + distance *= 1000u; + distance += Square(Intensity(predicted_value) + - Intensity(actual_value)); + return distance; +} + +static uint32_t Predict(int x, int y, uint32_t* image) { + const uint32_t t = (y == 0) ? ARGB_BLACK : image[x]; + const uint32_t l = (x == 0) ? ARGB_BLACK : image[x - 1]; + const uint32_t p = + (((((t >> 24) & 0xff) + ((l >> 24) & 0xff)) / 2) << 24) + + (((((t >> 16) & 0xff) + ((l >> 16) & 0xff)) / 2) << 16) + + (((((t >> 8) & 0xff) + ((l >> 8) & 0xff)) / 2) << 8) + + (((((t >> 0) & 0xff) + ((l >> 0) & 0xff)) / 2) << 0); + if (x == 0 && y == 0) return ARGB_BLACK; + if (x == 0) return t; + if (y == 0) return l; + return p; +} + +static WEBP_INLINE int AddSubtractComponentFullWithCoefficient( + int a, int b, int c) { + return Clip255(a + ((b - c) >> 2)); +} + +static WEBP_INLINE uint32_t ClampedAddSubtractFullWithCoefficient( + uint32_t c0, uint32_t c1, uint32_t c2) { + const int a = AddSubtractComponentFullWithCoefficient( + c0 >> 24, c1 >> 24, c2 >> 24); + const int r = AddSubtractComponentFullWithCoefficient((c0 >> 16) & 0xff, + (c1 >> 16) & 0xff, + (c2 >> 16) & 0xff); + const int g = AddSubtractComponentFullWithCoefficient((c0 >> 8) & 0xff, + (c1 >> 8) & 0xff, + (c2 >> 8) & 0xff); + const int b = AddSubtractComponentFullWithCoefficient( + c0 & 0xff, c1 & 0xff, c2 & 0xff); + return ((uint32_t)a << 24) | (r << 16) | (g << 8) | b; +} + +//------------------------------------------------------------------------------ + +// Find palette entry with minimum error from difference of actual pixel value +// and predicted pixel value. Propagate error of pixel to its top and left pixel +// in src array. Write predicted_value + palette_entry to new_image. Return +// index of best palette entry. +static int FindBestPaletteEntry(uint32_t src, uint32_t predicted_value, + const uint32_t palette[], int palette_size) { + int i; + int idx = 0; + uint32_t best_distance = CalcDist(predicted_value, src, palette[0]); + for (i = 1; i < palette_size; ++i) { + const uint32_t distance = CalcDist(predicted_value, src, palette[i]); + if (distance < best_distance) { + best_distance = distance; + idx = i; + } + } + return idx; +} + +static void ApplyBestPaletteEntry(int x, int y, + uint32_t new_value, uint32_t palette_value, + uint32_t* src, int src_stride, + uint32_t* new_image) { + AddPixelsEq(&new_value, palette_value); + if (x > 0) { + src[x - 1] = ClampedAddSubtractFullWithCoefficient(src[x - 1], + new_value, src[x]); + } + if (y > 0) { + src[x - src_stride] = + ClampedAddSubtractFullWithCoefficient(src[x - src_stride], + new_value, src[x]); + } + new_image[x] = new_value; +} + +//------------------------------------------------------------------------------ +// Main entry point + +static WebPEncodingError ApplyDeltaPalette(uint32_t* src, uint32_t* dst, + uint32_t src_stride, + uint32_t dst_stride, + const uint32_t* palette, + int palette_size, + int width, int height, + int num_passes) { + int x, y; + WebPEncodingError err = VP8_ENC_OK; + uint32_t* new_image = (uint32_t*)WebPSafeMalloc(width, sizeof(*new_image)); + uint8_t* const tmp_row = (uint8_t*)WebPSafeMalloc(width, sizeof(*tmp_row)); + if (new_image == NULL || tmp_row == NULL) { + err = VP8_ENC_ERROR_OUT_OF_MEMORY; + goto Error; + } + + while (num_passes--) { + uint32_t* cur_src = src; + uint32_t* cur_dst = dst; + for (y = 0; y < height; ++y) { + for (x = 0; x < width; ++x) { + const uint32_t predicted_value = Predict(x, y, new_image); + tmp_row[x] = FindBestPaletteEntry(cur_src[x], predicted_value, + palette, palette_size); + ApplyBestPaletteEntry(x, y, predicted_value, palette[tmp_row[x]], + cur_src, src_stride, new_image); + } + for (x = 0; x < width; ++x) { + cur_dst[x] = palette[tmp_row[x]]; + } + cur_src += src_stride; + cur_dst += dst_stride; + } + } + Error: + WebPSafeFree(new_image); + WebPSafeFree(tmp_row); + return err; +} + +// replaces enc->argb_ by a palettizable approximation of it, +// and generates optimal enc->palette_[] +WebPEncodingError WebPSearchOptimalDeltaPalette(VP8LEncoder* const enc) { + const WebPPicture* const pic = enc->pic_; + uint32_t* src = pic->argb; + uint32_t* dst = enc->argb_; + const int width = pic->width; + const int height = pic->height; + + WebPEncodingError err = VP8_ENC_OK; + memcpy(enc->palette_, kDeltaPalette, sizeof(kDeltaPalette)); + enc->palette_[DELTA_PALETTE_SIZE - 1] = src[0] - 0xff000000u; + enc->palette_size_ = DELTA_PALETTE_SIZE; + err = ApplyDeltaPalette(src, dst, pic->argb_stride, enc->current_width_, + enc->palette_, enc->palette_size_, + width, height, 2); + if (err != VP8_ENC_OK) goto Error; + + Error: + return err; +} + +#else // !WEBP_EXPERIMENTAL_FEATURES + +WebPEncodingError WebPSearchOptimalDeltaPalette(VP8LEncoder* const enc) { + (void)enc; + return VP8_ENC_ERROR_INVALID_CONFIGURATION; +} + +#endif // WEBP_EXPERIMENTAL_FEATURES diff --git a/drivers/webp/enc/delta_palettization.h b/drivers/webp/enc/delta_palettization.h new file mode 100644 index 0000000000..e41c0c5ab5 --- /dev/null +++ b/drivers/webp/enc/delta_palettization.h @@ -0,0 +1,25 @@ +// Copyright 2015 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// Author: Mislav Bradac (mislavm@google.com) +// + +#ifndef WEBP_ENC_DELTA_PALETTIZATION_H_ +#define WEBP_ENC_DELTA_PALETTIZATION_H_ + +#include "../webp/encode.h" +#include "../enc/vp8li.h" + +// Replaces enc->argb_[] input by a palettizable approximation of it, +// and generates optimal enc->palette_[]. +// This function can revert enc->use_palette_ / enc->use_predict_ flag +// if delta-palettization is not producing expected saving. +WebPEncodingError WebPSearchOptimalDeltaPalette(VP8LEncoder* const enc); + +#endif // WEBP_ENC_DELTA_PALETTIZATION_H_ diff --git a/drivers/webp/enc/near_lossless.c b/drivers/webp/enc/near_lossless.c new file mode 100644 index 0000000000..9bc0f0e786 --- /dev/null +++ b/drivers/webp/enc/near_lossless.c @@ -0,0 +1,160 @@ +// Copyright 2014 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// Near-lossless image preprocessing adjusts pixel values to help +// compressibility with a guarantee of maximum deviation between original and +// resulting pixel values. +// +// Author: Jyrki Alakuijala (jyrki@google.com) +// Converted to C by Aleksander Kramarz (akramarz@google.com) + +#include <stdlib.h> + +#include "../dsp/lossless.h" +#include "../utils/utils.h" +#include "./vp8enci.h" + +#define MIN_DIM_FOR_NEAR_LOSSLESS 64 +#define MAX_LIMIT_BITS 5 + +// Computes quantized pixel value and distance from original value. +static void GetValAndDistance(int a, int initial, int bits, + int* const val, int* const distance) { + const int mask = ~((1 << bits) - 1); + *val = (initial & mask) | (initial >> (8 - bits)); + *distance = 2 * abs(a - *val); +} + +// Clamps the value to range [0, 255]. +static int Clamp8b(int val) { + const int min_val = 0; + const int max_val = 0xff; + return (val < min_val) ? min_val : (val > max_val) ? max_val : val; +} + +// Quantizes values {a, a+(1<<bits), a-(1<<bits)} and returns the nearest one. +static int FindClosestDiscretized(int a, int bits) { + int best_val = a, i; + int min_distance = 256; + + for (i = -1; i <= 1; ++i) { + int candidate, distance; + const int val = Clamp8b(a + i * (1 << bits)); + GetValAndDistance(a, val, bits, &candidate, &distance); + if (i != 0) { + ++distance; + } + // Smallest distance but favor i == 0 over i == -1 and i == 1 + // since that keeps the overall intensity more constant in the + // images. + if (distance < min_distance) { + min_distance = distance; + best_val = candidate; + } + } + return best_val; +} + +// Applies FindClosestDiscretized to all channels of pixel. +static uint32_t ClosestDiscretizedArgb(uint32_t a, int bits) { + return + (FindClosestDiscretized(a >> 24, bits) << 24) | + (FindClosestDiscretized((a >> 16) & 0xff, bits) << 16) | + (FindClosestDiscretized((a >> 8) & 0xff, bits) << 8) | + (FindClosestDiscretized(a & 0xff, bits)); +} + +// Checks if distance between corresponding channel values of pixels a and b +// is within the given limit. +static int IsNear(uint32_t a, uint32_t b, int limit) { + int k; + for (k = 0; k < 4; ++k) { + const int delta = + (int)((a >> (k * 8)) & 0xff) - (int)((b >> (k * 8)) & 0xff); + if (delta >= limit || delta <= -limit) { + return 0; + } + } + return 1; +} + +static int IsSmooth(const uint32_t* const prev_row, + const uint32_t* const curr_row, + const uint32_t* const next_row, + int ix, int limit) { + // Check that all pixels in 4-connected neighborhood are smooth. + return (IsNear(curr_row[ix], curr_row[ix - 1], limit) && + IsNear(curr_row[ix], curr_row[ix + 1], limit) && + IsNear(curr_row[ix], prev_row[ix], limit) && + IsNear(curr_row[ix], next_row[ix], limit)); +} + +// Adjusts pixel values of image with given maximum error. +static void NearLossless(int xsize, int ysize, uint32_t* argb, + int limit_bits, uint32_t* copy_buffer) { + int x, y; + const int limit = 1 << limit_bits; + uint32_t* prev_row = copy_buffer; + uint32_t* curr_row = prev_row + xsize; + uint32_t* next_row = curr_row + xsize; + memcpy(copy_buffer, argb, xsize * 2 * sizeof(argb[0])); + + for (y = 1; y < ysize - 1; ++y) { + uint32_t* const curr_argb_row = argb + y * xsize; + uint32_t* const next_argb_row = curr_argb_row + xsize; + memcpy(next_row, next_argb_row, xsize * sizeof(argb[0])); + for (x = 1; x < xsize - 1; ++x) { + if (!IsSmooth(prev_row, curr_row, next_row, x, limit)) { + curr_argb_row[x] = ClosestDiscretizedArgb(curr_row[x], limit_bits); + } + } + { + // Three-way swap. + uint32_t* const temp = prev_row; + prev_row = curr_row; + curr_row = next_row; + next_row = temp; + } + } +} + +static int QualityToLimitBits(int quality) { + // quality mapping: + // 0..19 -> 5 + // 0..39 -> 4 + // 0..59 -> 3 + // 0..79 -> 2 + // 0..99 -> 1 + // 100 -> 0 + return MAX_LIMIT_BITS - quality / 20; +} + +int VP8ApplyNearLossless(int xsize, int ysize, uint32_t* argb, int quality) { + int i; + uint32_t* const copy_buffer = + (uint32_t*)WebPSafeMalloc(xsize * 3, sizeof(*copy_buffer)); + const int limit_bits = QualityToLimitBits(quality); + assert(argb != NULL); + assert(limit_bits >= 0); + assert(limit_bits <= MAX_LIMIT_BITS); + if (copy_buffer == NULL) { + return 0; + } + // For small icon images, don't attempt to apply near-lossless compression. + if (xsize < MIN_DIM_FOR_NEAR_LOSSLESS && ysize < MIN_DIM_FOR_NEAR_LOSSLESS) { + WebPSafeFree(copy_buffer); + return 1; + } + + for (i = limit_bits; i != 0; --i) { + NearLossless(xsize, ysize, argb, i, copy_buffer); + } + WebPSafeFree(copy_buffer); + return 1; +} diff --git a/drivers/webp/enc/picture_csp.c b/drivers/webp/enc/picture_csp.c new file mode 100644 index 0000000000..0ef5f9eee2 --- /dev/null +++ b/drivers/webp/enc/picture_csp.c @@ -0,0 +1,1156 @@ +// Copyright 2014 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// WebPPicture utils for colorspace conversion +// +// Author: Skal (pascal.massimino@gmail.com) + +#include <assert.h> +#include <stdlib.h> +#include <math.h> + +#include "./vp8enci.h" +#include "../utils/random.h" +#include "../utils/utils.h" +#include "../dsp/yuv.h" + +// Uncomment to disable gamma-compression during RGB->U/V averaging +#define USE_GAMMA_COMPRESSION + +// If defined, use table to compute x / alpha. +#define USE_INVERSE_ALPHA_TABLE + +static const union { + uint32_t argb; + uint8_t bytes[4]; +} test_endian = { 0xff000000u }; +#define ALPHA_IS_LAST (test_endian.bytes[3] == 0xff) + +//------------------------------------------------------------------------------ +// Detection of non-trivial transparency + +// Returns true if alpha[] has non-0xff values. +static int CheckNonOpaque(const uint8_t* alpha, int width, int height, + int x_step, int y_step) { + if (alpha == NULL) return 0; + while (height-- > 0) { + int x; + for (x = 0; x < width * x_step; x += x_step) { + if (alpha[x] != 0xff) return 1; // TODO(skal): check 4/8 bytes at a time. + } + alpha += y_step; + } + return 0; +} + +// Checking for the presence of non-opaque alpha. +int WebPPictureHasTransparency(const WebPPicture* picture) { + if (picture == NULL) return 0; + if (!picture->use_argb) { + return CheckNonOpaque(picture->a, picture->width, picture->height, + 1, picture->a_stride); + } else { + int x, y; + const uint32_t* argb = picture->argb; + if (argb == NULL) return 0; + for (y = 0; y < picture->height; ++y) { + for (x = 0; x < picture->width; ++x) { + if (argb[x] < 0xff000000u) return 1; // test any alpha values != 0xff + } + argb += picture->argb_stride; + } + } + return 0; +} + +//------------------------------------------------------------------------------ +// Code for gamma correction + +#if defined(USE_GAMMA_COMPRESSION) + +// gamma-compensates loss of resolution during chroma subsampling +#define kGamma 0.80 // for now we use a different gamma value than kGammaF +#define kGammaFix 12 // fixed-point precision for linear values +#define kGammaScale ((1 << kGammaFix) - 1) +#define kGammaTabFix 7 // fixed-point fractional bits precision +#define kGammaTabScale (1 << kGammaTabFix) +#define kGammaTabRounder (kGammaTabScale >> 1) +#define kGammaTabSize (1 << (kGammaFix - kGammaTabFix)) + +static int kLinearToGammaTab[kGammaTabSize + 1]; +static uint16_t kGammaToLinearTab[256]; +static volatile int kGammaTablesOk = 0; + +static WEBP_TSAN_IGNORE_FUNCTION void InitGammaTables(void) { + if (!kGammaTablesOk) { + int v; + const double scale = (double)(1 << kGammaTabFix) / kGammaScale; + const double norm = 1. / 255.; + for (v = 0; v <= 255; ++v) { + kGammaToLinearTab[v] = + (uint16_t)(pow(norm * v, kGamma) * kGammaScale + .5); + } + for (v = 0; v <= kGammaTabSize; ++v) { + kLinearToGammaTab[v] = (int)(255. * pow(scale * v, 1. / kGamma) + .5); + } + kGammaTablesOk = 1; + } +} + +static WEBP_INLINE uint32_t GammaToLinear(uint8_t v) { + return kGammaToLinearTab[v]; +} + +static WEBP_INLINE int Interpolate(int v) { + const int tab_pos = v >> (kGammaTabFix + 2); // integer part + const int x = v & ((kGammaTabScale << 2) - 1); // fractional part + const int v0 = kLinearToGammaTab[tab_pos]; + const int v1 = kLinearToGammaTab[tab_pos + 1]; + const int y = v1 * x + v0 * ((kGammaTabScale << 2) - x); // interpolate + assert(tab_pos + 1 < kGammaTabSize + 1); + return y; +} + +// Convert a linear value 'v' to YUV_FIX+2 fixed-point precision +// U/V value, suitable for RGBToU/V calls. +static WEBP_INLINE int LinearToGamma(uint32_t base_value, int shift) { + const int y = Interpolate(base_value << shift); // final uplifted value + return (y + kGammaTabRounder) >> kGammaTabFix; // descale +} + +#else + +static WEBP_TSAN_IGNORE_FUNCTION void InitGammaTables(void) {} +static WEBP_INLINE uint32_t GammaToLinear(uint8_t v) { return v; } +static WEBP_INLINE int LinearToGamma(uint32_t base_value, int shift) { + return (int)(base_value << shift); +} + +#endif // USE_GAMMA_COMPRESSION + +//------------------------------------------------------------------------------ +// RGB -> YUV conversion + +static int RGBToY(int r, int g, int b, VP8Random* const rg) { + return (rg == NULL) ? VP8RGBToY(r, g, b, YUV_HALF) + : VP8RGBToY(r, g, b, VP8RandomBits(rg, YUV_FIX)); +} + +static int RGBToU(int r, int g, int b, VP8Random* const rg) { + return (rg == NULL) ? VP8RGBToU(r, g, b, YUV_HALF << 2) + : VP8RGBToU(r, g, b, VP8RandomBits(rg, YUV_FIX + 2)); +} + +static int RGBToV(int r, int g, int b, VP8Random* const rg) { + return (rg == NULL) ? VP8RGBToV(r, g, b, YUV_HALF << 2) + : VP8RGBToV(r, g, b, VP8RandomBits(rg, YUV_FIX + 2)); +} + +//------------------------------------------------------------------------------ +// Smart RGB->YUV conversion + +static const int kNumIterations = 6; +static const int kMinDimensionIterativeConversion = 4; + +// We could use SFIX=0 and only uint8_t for fixed_y_t, but it produces some +// banding sometimes. Better use extra precision. +#define SFIX 2 // fixed-point precision of RGB and Y/W +typedef int16_t fixed_t; // signed type with extra SFIX precision for UV +typedef uint16_t fixed_y_t; // unsigned type with extra SFIX precision for W + +#define SHALF (1 << SFIX >> 1) +#define MAX_Y_T ((256 << SFIX) - 1) +#define SROUNDER (1 << (YUV_FIX + SFIX - 1)) + +#if defined(USE_GAMMA_COMPRESSION) + +// float variant of gamma-correction +// We use tables of different size and precision, along with a 'real-world' +// Gamma value close to ~2. +#define kGammaF 2.2 +static float kGammaToLinearTabF[MAX_Y_T + 1]; // size scales with Y_FIX +static float kLinearToGammaTabF[kGammaTabSize + 2]; +static volatile int kGammaTablesFOk = 0; + +static WEBP_TSAN_IGNORE_FUNCTION void InitGammaTablesF(void) { + if (!kGammaTablesFOk) { + int v; + const double norm = 1. / MAX_Y_T; + const double scale = 1. / kGammaTabSize; + for (v = 0; v <= MAX_Y_T; ++v) { + kGammaToLinearTabF[v] = (float)pow(norm * v, kGammaF); + } + for (v = 0; v <= kGammaTabSize; ++v) { + kLinearToGammaTabF[v] = (float)(MAX_Y_T * pow(scale * v, 1. / kGammaF)); + } + // to prevent small rounding errors to cause read-overflow: + kLinearToGammaTabF[kGammaTabSize + 1] = kLinearToGammaTabF[kGammaTabSize]; + kGammaTablesFOk = 1; + } +} + +static WEBP_INLINE float GammaToLinearF(int v) { + return kGammaToLinearTabF[v]; +} + +static WEBP_INLINE int LinearToGammaF(float value) { + const float v = value * kGammaTabSize; + const int tab_pos = (int)v; + const float x = v - (float)tab_pos; // fractional part + const float v0 = kLinearToGammaTabF[tab_pos + 0]; + const float v1 = kLinearToGammaTabF[tab_pos + 1]; + const float y = v1 * x + v0 * (1.f - x); // interpolate + return (int)(y + .5); +} + +#else + +static WEBP_TSAN_IGNORE_FUNCTION void InitGammaTablesF(void) {} +static WEBP_INLINE float GammaToLinearF(int v) { + const float norm = 1.f / MAX_Y_T; + return norm * v; +} +static WEBP_INLINE int LinearToGammaF(float value) { + return (int)(MAX_Y_T * value + .5); +} + +#endif // USE_GAMMA_COMPRESSION + +//------------------------------------------------------------------------------ + +static uint8_t clip_8b(fixed_t v) { + return (!(v & ~0xff)) ? (uint8_t)v : (v < 0) ? 0u : 255u; +} + +static fixed_y_t clip_y(int y) { + return (!(y & ~MAX_Y_T)) ? (fixed_y_t)y : (y < 0) ? 0 : MAX_Y_T; +} + +//------------------------------------------------------------------------------ + +static int RGBToGray(int r, int g, int b) { + const int luma = 19595 * r + 38470 * g + 7471 * b + YUV_HALF; + return (luma >> YUV_FIX); +} + +static float RGBToGrayF(float r, float g, float b) { + return 0.299f * r + 0.587f * g + 0.114f * b; +} + +static int ScaleDown(int a, int b, int c, int d) { + const float A = GammaToLinearF(a); + const float B = GammaToLinearF(b); + const float C = GammaToLinearF(c); + const float D = GammaToLinearF(d); + return LinearToGammaF(0.25f * (A + B + C + D)); +} + +static WEBP_INLINE void UpdateW(const fixed_y_t* src, fixed_y_t* dst, int len) { + while (len-- > 0) { + const float R = GammaToLinearF(src[0]); + const float G = GammaToLinearF(src[1]); + const float B = GammaToLinearF(src[2]); + const float Y = RGBToGrayF(R, G, B); + *dst++ = (fixed_y_t)LinearToGammaF(Y); + src += 3; + } +} + +static int UpdateChroma(const fixed_y_t* src1, + const fixed_y_t* src2, + fixed_t* dst, fixed_y_t* tmp, int len) { + int diff = 0; + while (len--> 0) { + const int r = ScaleDown(src1[0], src1[3], src2[0], src2[3]); + const int g = ScaleDown(src1[1], src1[4], src2[1], src2[4]); + const int b = ScaleDown(src1[2], src1[5], src2[2], src2[5]); + const int W = RGBToGray(r, g, b); + const int r_avg = (src1[0] + src1[3] + src2[0] + src2[3] + 2) >> 2; + const int g_avg = (src1[1] + src1[4] + src2[1] + src2[4] + 2) >> 2; + const int b_avg = (src1[2] + src1[5] + src2[2] + src2[5] + 2) >> 2; + dst[0] = (fixed_t)(r - W); + dst[1] = (fixed_t)(g - W); + dst[2] = (fixed_t)(b - W); + dst += 3; + src1 += 6; + src2 += 6; + if (tmp != NULL) { + tmp[0] = tmp[1] = clip_y(W); + tmp += 2; + } + diff += abs(RGBToGray(r_avg, g_avg, b_avg) - W); + } + return diff; +} + +//------------------------------------------------------------------------------ + +static WEBP_INLINE int Filter(const fixed_t* const A, const fixed_t* const B, + int rightwise) { + int v; + if (!rightwise) { + v = (A[0] * 9 + A[-3] * 3 + B[0] * 3 + B[-3]); + } else { + v = (A[0] * 9 + A[+3] * 3 + B[0] * 3 + B[+3]); + } + return (v + 8) >> 4; +} + +static WEBP_INLINE int Filter2(int A, int B) { return (A * 3 + B + 2) >> 2; } + +//------------------------------------------------------------------------------ + +static WEBP_INLINE fixed_y_t UpLift(uint8_t a) { // 8bit -> SFIX + return ((fixed_y_t)a << SFIX) | SHALF; +} + +static void ImportOneRow(const uint8_t* const r_ptr, + const uint8_t* const g_ptr, + const uint8_t* const b_ptr, + int step, + int pic_width, + fixed_y_t* const dst) { + int i; + for (i = 0; i < pic_width; ++i) { + const int off = i * step; + dst[3 * i + 0] = UpLift(r_ptr[off]); + dst[3 * i + 1] = UpLift(g_ptr[off]); + dst[3 * i + 2] = UpLift(b_ptr[off]); + } + if (pic_width & 1) { // replicate rightmost pixel + memcpy(dst + 3 * pic_width, dst + 3 * (pic_width - 1), 3 * sizeof(*dst)); + } +} + +static void InterpolateTwoRows(const fixed_y_t* const best_y, + const fixed_t* const prev_uv, + const fixed_t* const cur_uv, + const fixed_t* const next_uv, + int w, + fixed_y_t* const out1, + fixed_y_t* const out2) { + int i, k; + { // special boundary case for i==0 + const int W0 = best_y[0]; + const int W1 = best_y[w]; + for (k = 0; k <= 2; ++k) { + out1[k] = clip_y(Filter2(cur_uv[k], prev_uv[k]) + W0); + out2[k] = clip_y(Filter2(cur_uv[k], next_uv[k]) + W1); + } + } + for (i = 1; i < w - 1; ++i) { + const int W0 = best_y[i + 0]; + const int W1 = best_y[i + w]; + const int off = 3 * (i >> 1); + for (k = 0; k <= 2; ++k) { + const int tmp0 = Filter(cur_uv + off + k, prev_uv + off + k, i & 1); + const int tmp1 = Filter(cur_uv + off + k, next_uv + off + k, i & 1); + out1[3 * i + k] = clip_y(tmp0 + W0); + out2[3 * i + k] = clip_y(tmp1 + W1); + } + } + { // special boundary case for i == w - 1 + const int W0 = best_y[i + 0]; + const int W1 = best_y[i + w]; + const int off = 3 * (i >> 1); + for (k = 0; k <= 2; ++k) { + out1[3 * i + k] = clip_y(Filter2(cur_uv[off + k], prev_uv[off + k]) + W0); + out2[3 * i + k] = clip_y(Filter2(cur_uv[off + k], next_uv[off + k]) + W1); + } + } +} + +static WEBP_INLINE uint8_t ConvertRGBToY(int r, int g, int b) { + const int luma = 16839 * r + 33059 * g + 6420 * b + SROUNDER; + return clip_8b(16 + (luma >> (YUV_FIX + SFIX))); +} + +static WEBP_INLINE uint8_t ConvertRGBToU(int r, int g, int b) { + const int u = -9719 * r - 19081 * g + 28800 * b + SROUNDER; + return clip_8b(128 + (u >> (YUV_FIX + SFIX))); +} + +static WEBP_INLINE uint8_t ConvertRGBToV(int r, int g, int b) { + const int v = +28800 * r - 24116 * g - 4684 * b + SROUNDER; + return clip_8b(128 + (v >> (YUV_FIX + SFIX))); +} + +static int ConvertWRGBToYUV(const fixed_y_t* const best_y, + const fixed_t* const best_uv, + WebPPicture* const picture) { + int i, j; + const int w = (picture->width + 1) & ~1; + const int h = (picture->height + 1) & ~1; + const int uv_w = w >> 1; + const int uv_h = h >> 1; + for (j = 0; j < picture->height; ++j) { + for (i = 0; i < picture->width; ++i) { + const int off = 3 * ((i >> 1) + (j >> 1) * uv_w); + const int off2 = i + j * picture->y_stride; + const int W = best_y[i + j * w]; + const int r = best_uv[off + 0] + W; + const int g = best_uv[off + 1] + W; + const int b = best_uv[off + 2] + W; + picture->y[off2] = ConvertRGBToY(r, g, b); + } + } + for (j = 0; j < uv_h; ++j) { + uint8_t* const dst_u = picture->u + j * picture->uv_stride; + uint8_t* const dst_v = picture->v + j * picture->uv_stride; + for (i = 0; i < uv_w; ++i) { + const int off = 3 * (i + j * uv_w); + const int r = best_uv[off + 0]; + const int g = best_uv[off + 1]; + const int b = best_uv[off + 2]; + dst_u[i] = ConvertRGBToU(r, g, b); + dst_v[i] = ConvertRGBToV(r, g, b); + } + } + return 1; +} + +//------------------------------------------------------------------------------ +// Main function + +#define SAFE_ALLOC(W, H, T) ((T*)WebPSafeMalloc((W) * (H), sizeof(T))) + +static int PreprocessARGB(const uint8_t* const r_ptr, + const uint8_t* const g_ptr, + const uint8_t* const b_ptr, + int step, int rgb_stride, + WebPPicture* const picture) { + // we expand the right/bottom border if needed + const int w = (picture->width + 1) & ~1; + const int h = (picture->height + 1) & ~1; + const int uv_w = w >> 1; + const int uv_h = h >> 1; + int i, j, iter; + + // TODO(skal): allocate one big memory chunk. But for now, it's easier + // for valgrind debugging to have several chunks. + fixed_y_t* const tmp_buffer = SAFE_ALLOC(w * 3, 2, fixed_y_t); // scratch + fixed_y_t* const best_y = SAFE_ALLOC(w, h, fixed_y_t); + fixed_y_t* const target_y = SAFE_ALLOC(w, h, fixed_y_t); + fixed_y_t* const best_rgb_y = SAFE_ALLOC(w, 2, fixed_y_t); + fixed_t* const best_uv = SAFE_ALLOC(uv_w * 3, uv_h, fixed_t); + fixed_t* const target_uv = SAFE_ALLOC(uv_w * 3, uv_h, fixed_t); + fixed_t* const best_rgb_uv = SAFE_ALLOC(uv_w * 3, 1, fixed_t); + int ok; + int diff_sum = 0; + const int first_diff_threshold = (int)(2.5 * w * h); + const int min_improvement = 5; // stop if improvement is below this % + const int min_first_improvement = 80; + + if (best_y == NULL || best_uv == NULL || + target_y == NULL || target_uv == NULL || + best_rgb_y == NULL || best_rgb_uv == NULL || + tmp_buffer == NULL) { + ok = WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY); + goto End; + } + assert(picture->width >= kMinDimensionIterativeConversion); + assert(picture->height >= kMinDimensionIterativeConversion); + + // Import RGB samples to W/RGB representation. + for (j = 0; j < picture->height; j += 2) { + const int is_last_row = (j == picture->height - 1); + fixed_y_t* const src1 = tmp_buffer; + fixed_y_t* const src2 = tmp_buffer + 3 * w; + const int off1 = j * rgb_stride; + const int off2 = off1 + rgb_stride; + const int uv_off = (j >> 1) * 3 * uv_w; + fixed_y_t* const dst_y = best_y + j * w; + + // prepare two rows of input + ImportOneRow(r_ptr + off1, g_ptr + off1, b_ptr + off1, + step, picture->width, src1); + if (!is_last_row) { + ImportOneRow(r_ptr + off2, g_ptr + off2, b_ptr + off2, + step, picture->width, src2); + } else { + memcpy(src2, src1, 3 * w * sizeof(*src2)); + } + UpdateW(src1, target_y + (j + 0) * w, w); + UpdateW(src2, target_y + (j + 1) * w, w); + diff_sum += UpdateChroma(src1, src2, target_uv + uv_off, dst_y, uv_w); + memcpy(best_uv + uv_off, target_uv + uv_off, 3 * uv_w * sizeof(*best_uv)); + memcpy(dst_y + w, dst_y, w * sizeof(*dst_y)); + } + + // Iterate and resolve clipping conflicts. + for (iter = 0; iter < kNumIterations; ++iter) { + int k; + const fixed_t* cur_uv = best_uv; + const fixed_t* prev_uv = best_uv; + const int old_diff_sum = diff_sum; + diff_sum = 0; + for (j = 0; j < h; j += 2) { + fixed_y_t* const src1 = tmp_buffer; + fixed_y_t* const src2 = tmp_buffer + 3 * w; + { + const fixed_t* const next_uv = cur_uv + ((j < h - 2) ? 3 * uv_w : 0); + InterpolateTwoRows(best_y + j * w, prev_uv, cur_uv, next_uv, + w, src1, src2); + prev_uv = cur_uv; + cur_uv = next_uv; + } + + UpdateW(src1, best_rgb_y + 0 * w, w); + UpdateW(src2, best_rgb_y + 1 * w, w); + diff_sum += UpdateChroma(src1, src2, best_rgb_uv, NULL, uv_w); + + // update two rows of Y and one row of RGB + for (i = 0; i < 2 * w; ++i) { + const int off = i + j * w; + const int diff_y = target_y[off] - best_rgb_y[i]; + const int new_y = (int)best_y[off] + diff_y; + best_y[off] = clip_y(new_y); + } + for (i = 0; i < uv_w; ++i) { + const int off = 3 * (i + (j >> 1) * uv_w); + int W; + for (k = 0; k <= 2; ++k) { + const int diff_uv = (int)target_uv[off + k] - best_rgb_uv[3 * i + k]; + best_uv[off + k] += diff_uv; + } + W = RGBToGray(best_uv[off + 0], best_uv[off + 1], best_uv[off + 2]); + for (k = 0; k <= 2; ++k) { + best_uv[off + k] -= W; + } + } + } + // test exit condition + if (diff_sum > 0) { + const int improvement = 100 * abs(diff_sum - old_diff_sum) / diff_sum; + // Check if first iteration gave good result already, without a large + // jump of improvement (otherwise it means we need to try few extra + // iterations, just to be sure). + if (iter == 0 && diff_sum < first_diff_threshold && + improvement < min_first_improvement) { + break; + } + // then, check if improvement is stalling. + if (improvement < min_improvement) { + break; + } + } else { + break; + } + } + + // final reconstruction + ok = ConvertWRGBToYUV(best_y, best_uv, picture); + + End: + WebPSafeFree(best_y); + WebPSafeFree(best_uv); + WebPSafeFree(target_y); + WebPSafeFree(target_uv); + WebPSafeFree(best_rgb_y); + WebPSafeFree(best_rgb_uv); + WebPSafeFree(tmp_buffer); + return ok; +} +#undef SAFE_ALLOC + +//------------------------------------------------------------------------------ +// "Fast" regular RGB->YUV + +#define SUM4(ptr, step) LinearToGamma( \ + GammaToLinear((ptr)[0]) + \ + GammaToLinear((ptr)[(step)]) + \ + GammaToLinear((ptr)[rgb_stride]) + \ + GammaToLinear((ptr)[rgb_stride + (step)]), 0) \ + +#define SUM2(ptr) \ + LinearToGamma(GammaToLinear((ptr)[0]) + GammaToLinear((ptr)[rgb_stride]), 1) + +#define SUM2ALPHA(ptr) ((ptr)[0] + (ptr)[rgb_stride]) +#define SUM4ALPHA(ptr) (SUM2ALPHA(ptr) + SUM2ALPHA((ptr) + 4)) + +#if defined(USE_INVERSE_ALPHA_TABLE) + +static const int kAlphaFix = 19; +// Following table is (1 << kAlphaFix) / a. The (v * kInvAlpha[a]) >> kAlphaFix +// formula is then equal to v / a in most (99.6%) cases. Note that this table +// and constant are adjusted very tightly to fit 32b arithmetic. +// In particular, they use the fact that the operands for 'v / a' are actually +// derived as v = (a0.p0 + a1.p1 + a2.p2 + a3.p3) and a = a0 + a1 + a2 + a3 +// with ai in [0..255] and pi in [0..1<<kGammaFix). The constraint to avoid +// overflow is: kGammaFix + kAlphaFix <= 31. +static const uint32_t kInvAlpha[4 * 0xff + 1] = { + 0, /* alpha = 0 */ + 524288, 262144, 174762, 131072, 104857, 87381, 74898, 65536, + 58254, 52428, 47662, 43690, 40329, 37449, 34952, 32768, + 30840, 29127, 27594, 26214, 24966, 23831, 22795, 21845, + 20971, 20164, 19418, 18724, 18078, 17476, 16912, 16384, + 15887, 15420, 14979, 14563, 14169, 13797, 13443, 13107, + 12787, 12483, 12192, 11915, 11650, 11397, 11155, 10922, + 10699, 10485, 10280, 10082, 9892, 9709, 9532, 9362, + 9198, 9039, 8886, 8738, 8594, 8456, 8322, 8192, + 8065, 7943, 7825, 7710, 7598, 7489, 7384, 7281, + 7182, 7084, 6990, 6898, 6808, 6721, 6636, 6553, + 6472, 6393, 6316, 6241, 6168, 6096, 6026, 5957, + 5890, 5825, 5761, 5698, 5637, 5577, 5518, 5461, + 5405, 5349, 5295, 5242, 5190, 5140, 5090, 5041, + 4993, 4946, 4899, 4854, 4809, 4766, 4723, 4681, + 4639, 4599, 4559, 4519, 4481, 4443, 4405, 4369, + 4332, 4297, 4262, 4228, 4194, 4161, 4128, 4096, + 4064, 4032, 4002, 3971, 3942, 3912, 3883, 3855, + 3826, 3799, 3771, 3744, 3718, 3692, 3666, 3640, + 3615, 3591, 3566, 3542, 3518, 3495, 3472, 3449, + 3426, 3404, 3382, 3360, 3339, 3318, 3297, 3276, + 3256, 3236, 3216, 3196, 3177, 3158, 3139, 3120, + 3102, 3084, 3066, 3048, 3030, 3013, 2995, 2978, + 2962, 2945, 2928, 2912, 2896, 2880, 2864, 2849, + 2833, 2818, 2803, 2788, 2774, 2759, 2744, 2730, + 2716, 2702, 2688, 2674, 2661, 2647, 2634, 2621, + 2608, 2595, 2582, 2570, 2557, 2545, 2532, 2520, + 2508, 2496, 2484, 2473, 2461, 2449, 2438, 2427, + 2416, 2404, 2394, 2383, 2372, 2361, 2351, 2340, + 2330, 2319, 2309, 2299, 2289, 2279, 2269, 2259, + 2250, 2240, 2231, 2221, 2212, 2202, 2193, 2184, + 2175, 2166, 2157, 2148, 2139, 2131, 2122, 2114, + 2105, 2097, 2088, 2080, 2072, 2064, 2056, 2048, + 2040, 2032, 2024, 2016, 2008, 2001, 1993, 1985, + 1978, 1971, 1963, 1956, 1949, 1941, 1934, 1927, + 1920, 1913, 1906, 1899, 1892, 1885, 1879, 1872, + 1865, 1859, 1852, 1846, 1839, 1833, 1826, 1820, + 1814, 1807, 1801, 1795, 1789, 1783, 1777, 1771, + 1765, 1759, 1753, 1747, 1741, 1736, 1730, 1724, + 1718, 1713, 1707, 1702, 1696, 1691, 1685, 1680, + 1675, 1669, 1664, 1659, 1653, 1648, 1643, 1638, + 1633, 1628, 1623, 1618, 1613, 1608, 1603, 1598, + 1593, 1588, 1583, 1579, 1574, 1569, 1565, 1560, + 1555, 1551, 1546, 1542, 1537, 1533, 1528, 1524, + 1519, 1515, 1510, 1506, 1502, 1497, 1493, 1489, + 1485, 1481, 1476, 1472, 1468, 1464, 1460, 1456, + 1452, 1448, 1444, 1440, 1436, 1432, 1428, 1424, + 1420, 1416, 1413, 1409, 1405, 1401, 1398, 1394, + 1390, 1387, 1383, 1379, 1376, 1372, 1368, 1365, + 1361, 1358, 1354, 1351, 1347, 1344, 1340, 1337, + 1334, 1330, 1327, 1323, 1320, 1317, 1314, 1310, + 1307, 1304, 1300, 1297, 1294, 1291, 1288, 1285, + 1281, 1278, 1275, 1272, 1269, 1266, 1263, 1260, + 1257, 1254, 1251, 1248, 1245, 1242, 1239, 1236, + 1233, 1230, 1227, 1224, 1222, 1219, 1216, 1213, + 1210, 1208, 1205, 1202, 1199, 1197, 1194, 1191, + 1188, 1186, 1183, 1180, 1178, 1175, 1172, 1170, + 1167, 1165, 1162, 1159, 1157, 1154, 1152, 1149, + 1147, 1144, 1142, 1139, 1137, 1134, 1132, 1129, + 1127, 1125, 1122, 1120, 1117, 1115, 1113, 1110, + 1108, 1106, 1103, 1101, 1099, 1096, 1094, 1092, + 1089, 1087, 1085, 1083, 1081, 1078, 1076, 1074, + 1072, 1069, 1067, 1065, 1063, 1061, 1059, 1057, + 1054, 1052, 1050, 1048, 1046, 1044, 1042, 1040, + 1038, 1036, 1034, 1032, 1030, 1028, 1026, 1024, + 1022, 1020, 1018, 1016, 1014, 1012, 1010, 1008, + 1006, 1004, 1002, 1000, 998, 996, 994, 992, + 991, 989, 987, 985, 983, 981, 979, 978, + 976, 974, 972, 970, 969, 967, 965, 963, + 961, 960, 958, 956, 954, 953, 951, 949, + 948, 946, 944, 942, 941, 939, 937, 936, + 934, 932, 931, 929, 927, 926, 924, 923, + 921, 919, 918, 916, 914, 913, 911, 910, + 908, 907, 905, 903, 902, 900, 899, 897, + 896, 894, 893, 891, 890, 888, 887, 885, + 884, 882, 881, 879, 878, 876, 875, 873, + 872, 870, 869, 868, 866, 865, 863, 862, + 860, 859, 858, 856, 855, 853, 852, 851, + 849, 848, 846, 845, 844, 842, 841, 840, + 838, 837, 836, 834, 833, 832, 830, 829, + 828, 826, 825, 824, 823, 821, 820, 819, + 817, 816, 815, 814, 812, 811, 810, 809, + 807, 806, 805, 804, 802, 801, 800, 799, + 798, 796, 795, 794, 793, 791, 790, 789, + 788, 787, 786, 784, 783, 782, 781, 780, + 779, 777, 776, 775, 774, 773, 772, 771, + 769, 768, 767, 766, 765, 764, 763, 762, + 760, 759, 758, 757, 756, 755, 754, 753, + 752, 751, 750, 748, 747, 746, 745, 744, + 743, 742, 741, 740, 739, 738, 737, 736, + 735, 734, 733, 732, 731, 730, 729, 728, + 727, 726, 725, 724, 723, 722, 721, 720, + 719, 718, 717, 716, 715, 714, 713, 712, + 711, 710, 709, 708, 707, 706, 705, 704, + 703, 702, 701, 700, 699, 699, 698, 697, + 696, 695, 694, 693, 692, 691, 690, 689, + 688, 688, 687, 686, 685, 684, 683, 682, + 681, 680, 680, 679, 678, 677, 676, 675, + 674, 673, 673, 672, 671, 670, 669, 668, + 667, 667, 666, 665, 664, 663, 662, 661, + 661, 660, 659, 658, 657, 657, 656, 655, + 654, 653, 652, 652, 651, 650, 649, 648, + 648, 647, 646, 645, 644, 644, 643, 642, + 641, 640, 640, 639, 638, 637, 637, 636, + 635, 634, 633, 633, 632, 631, 630, 630, + 629, 628, 627, 627, 626, 625, 624, 624, + 623, 622, 621, 621, 620, 619, 618, 618, + 617, 616, 616, 615, 614, 613, 613, 612, + 611, 611, 610, 609, 608, 608, 607, 606, + 606, 605, 604, 604, 603, 602, 601, 601, + 600, 599, 599, 598, 597, 597, 596, 595, + 595, 594, 593, 593, 592, 591, 591, 590, + 589, 589, 588, 587, 587, 586, 585, 585, + 584, 583, 583, 582, 581, 581, 580, 579, + 579, 578, 578, 577, 576, 576, 575, 574, + 574, 573, 572, 572, 571, 571, 570, 569, + 569, 568, 568, 567, 566, 566, 565, 564, + 564, 563, 563, 562, 561, 561, 560, 560, + 559, 558, 558, 557, 557, 556, 555, 555, + 554, 554, 553, 553, 552, 551, 551, 550, + 550, 549, 548, 548, 547, 547, 546, 546, + 545, 544, 544, 543, 543, 542, 542, 541, + 541, 540, 539, 539, 538, 538, 537, 537, + 536, 536, 535, 534, 534, 533, 533, 532, + 532, 531, 531, 530, 530, 529, 529, 528, + 527, 527, 526, 526, 525, 525, 524, 524, + 523, 523, 522, 522, 521, 521, 520, 520, + 519, 519, 518, 518, 517, 517, 516, 516, + 515, 515, 514, 514 +}; + +// Note that LinearToGamma() expects the values to be premultiplied by 4, +// so we incorporate this factor 4 inside the DIVIDE_BY_ALPHA macro directly. +#define DIVIDE_BY_ALPHA(sum, a) (((sum) * kInvAlpha[(a)]) >> (kAlphaFix - 2)) + +#else + +#define DIVIDE_BY_ALPHA(sum, a) (4 * (sum) / (a)) + +#endif // USE_INVERSE_ALPHA_TABLE + +static WEBP_INLINE int LinearToGammaWeighted(const uint8_t* src, + const uint8_t* a_ptr, + uint32_t total_a, int step, + int rgb_stride) { + const uint32_t sum = + a_ptr[0] * GammaToLinear(src[0]) + + a_ptr[step] * GammaToLinear(src[step]) + + a_ptr[rgb_stride] * GammaToLinear(src[rgb_stride]) + + a_ptr[rgb_stride + step] * GammaToLinear(src[rgb_stride + step]); + assert(total_a > 0 && total_a <= 4 * 0xff); +#if defined(USE_INVERSE_ALPHA_TABLE) + assert((uint64_t)sum * kInvAlpha[total_a] < ((uint64_t)1 << 32)); +#endif + return LinearToGamma(DIVIDE_BY_ALPHA(sum, total_a), 0); +} + +static WEBP_INLINE void ConvertRowToY(const uint8_t* const r_ptr, + const uint8_t* const g_ptr, + const uint8_t* const b_ptr, + int step, + uint8_t* const dst_y, + int width, + VP8Random* const rg) { + int i, j; + for (i = 0, j = 0; i < width; i += 1, j += step) { + dst_y[i] = RGBToY(r_ptr[j], g_ptr[j], b_ptr[j], rg); + } +} + +static WEBP_INLINE void AccumulateRGBA(const uint8_t* const r_ptr, + const uint8_t* const g_ptr, + const uint8_t* const b_ptr, + const uint8_t* const a_ptr, + int rgb_stride, + uint16_t* dst, int width) { + int i, j; + // we loop over 2x2 blocks and produce one R/G/B/A value for each. + for (i = 0, j = 0; i < (width >> 1); i += 1, j += 2 * 4, dst += 4) { + const uint32_t a = SUM4ALPHA(a_ptr + j); + int r, g, b; + if (a == 4 * 0xff || a == 0) { + r = SUM4(r_ptr + j, 4); + g = SUM4(g_ptr + j, 4); + b = SUM4(b_ptr + j, 4); + } else { + r = LinearToGammaWeighted(r_ptr + j, a_ptr + j, a, 4, rgb_stride); + g = LinearToGammaWeighted(g_ptr + j, a_ptr + j, a, 4, rgb_stride); + b = LinearToGammaWeighted(b_ptr + j, a_ptr + j, a, 4, rgb_stride); + } + dst[0] = r; + dst[1] = g; + dst[2] = b; + dst[3] = a; + } + if (width & 1) { + const uint32_t a = 2u * SUM2ALPHA(a_ptr + j); + int r, g, b; + if (a == 4 * 0xff || a == 0) { + r = SUM2(r_ptr + j); + g = SUM2(g_ptr + j); + b = SUM2(b_ptr + j); + } else { + r = LinearToGammaWeighted(r_ptr + j, a_ptr + j, a, 0, rgb_stride); + g = LinearToGammaWeighted(g_ptr + j, a_ptr + j, a, 0, rgb_stride); + b = LinearToGammaWeighted(b_ptr + j, a_ptr + j, a, 0, rgb_stride); + } + dst[0] = r; + dst[1] = g; + dst[2] = b; + dst[3] = a; + } +} + +static WEBP_INLINE void AccumulateRGB(const uint8_t* const r_ptr, + const uint8_t* const g_ptr, + const uint8_t* const b_ptr, + int step, int rgb_stride, + uint16_t* dst, int width) { + int i, j; + for (i = 0, j = 0; i < (width >> 1); i += 1, j += 2 * step, dst += 4) { + dst[0] = SUM4(r_ptr + j, step); + dst[1] = SUM4(g_ptr + j, step); + dst[2] = SUM4(b_ptr + j, step); + } + if (width & 1) { + dst[0] = SUM2(r_ptr + j); + dst[1] = SUM2(g_ptr + j); + dst[2] = SUM2(b_ptr + j); + } +} + +static WEBP_INLINE void ConvertRowsToUV(const uint16_t* rgb, + uint8_t* const dst_u, + uint8_t* const dst_v, + int width, + VP8Random* const rg) { + int i; + for (i = 0; i < width; i += 1, rgb += 4) { + const int r = rgb[0], g = rgb[1], b = rgb[2]; + dst_u[i] = RGBToU(r, g, b, rg); + dst_v[i] = RGBToV(r, g, b, rg); + } +} + +static int ImportYUVAFromRGBA(const uint8_t* const r_ptr, + const uint8_t* const g_ptr, + const uint8_t* const b_ptr, + const uint8_t* const a_ptr, + int step, // bytes per pixel + int rgb_stride, // bytes per scanline + float dithering, + int use_iterative_conversion, + WebPPicture* const picture) { + int y; + const int width = picture->width; + const int height = picture->height; + const int has_alpha = CheckNonOpaque(a_ptr, width, height, step, rgb_stride); + const int is_rgb = (r_ptr < b_ptr); // otherwise it's bgr + + picture->colorspace = has_alpha ? WEBP_YUV420A : WEBP_YUV420; + picture->use_argb = 0; + + // disable smart conversion if source is too small (overkill). + if (width < kMinDimensionIterativeConversion || + height < kMinDimensionIterativeConversion) { + use_iterative_conversion = 0; + } + + if (!WebPPictureAllocYUVA(picture, width, height)) { + return 0; + } + if (has_alpha) { + WebPInitAlphaProcessing(); + assert(step == 4); +#if defined(USE_GAMMA_COMPRESSION) && defined(USE_INVERSE_ALPHA_TABLE) + assert(kAlphaFix + kGammaFix <= 31); +#endif + } + + if (use_iterative_conversion) { + InitGammaTablesF(); + if (!PreprocessARGB(r_ptr, g_ptr, b_ptr, step, rgb_stride, picture)) { + return 0; + } + if (has_alpha) { + WebPExtractAlpha(a_ptr, rgb_stride, width, height, + picture->a, picture->a_stride); + } + } else { + const int uv_width = (width + 1) >> 1; + int use_dsp = (step == 3); // use special function in this case + // temporary storage for accumulated R/G/B values during conversion to U/V + uint16_t* const tmp_rgb = + (uint16_t*)WebPSafeMalloc(4 * uv_width, sizeof(*tmp_rgb)); + uint8_t* dst_y = picture->y; + uint8_t* dst_u = picture->u; + uint8_t* dst_v = picture->v; + uint8_t* dst_a = picture->a; + + VP8Random base_rg; + VP8Random* rg = NULL; + if (dithering > 0.) { + VP8InitRandom(&base_rg, dithering); + rg = &base_rg; + use_dsp = 0; // can't use dsp in this case + } + WebPInitConvertARGBToYUV(); + InitGammaTables(); + + if (tmp_rgb == NULL) return 0; // malloc error + + // Downsample Y/U/V planes, two rows at a time + for (y = 0; y < (height >> 1); ++y) { + int rows_have_alpha = has_alpha; + const int off1 = (2 * y + 0) * rgb_stride; + const int off2 = (2 * y + 1) * rgb_stride; + if (use_dsp) { + if (is_rgb) { + WebPConvertRGB24ToY(r_ptr + off1, dst_y, width); + WebPConvertRGB24ToY(r_ptr + off2, dst_y + picture->y_stride, width); + } else { + WebPConvertBGR24ToY(b_ptr + off1, dst_y, width); + WebPConvertBGR24ToY(b_ptr + off2, dst_y + picture->y_stride, width); + } + } else { + ConvertRowToY(r_ptr + off1, g_ptr + off1, b_ptr + off1, step, + dst_y, width, rg); + ConvertRowToY(r_ptr + off2, g_ptr + off2, b_ptr + off2, step, + dst_y + picture->y_stride, width, rg); + } + dst_y += 2 * picture->y_stride; + if (has_alpha) { + rows_have_alpha &= !WebPExtractAlpha(a_ptr + off1, rgb_stride, + width, 2, + dst_a, picture->a_stride); + dst_a += 2 * picture->a_stride; + } + // Collect averaged R/G/B(/A) + if (!rows_have_alpha) { + AccumulateRGB(r_ptr + off1, g_ptr + off1, b_ptr + off1, + step, rgb_stride, tmp_rgb, width); + } else { + AccumulateRGBA(r_ptr + off1, g_ptr + off1, b_ptr + off1, a_ptr + off1, + rgb_stride, tmp_rgb, width); + } + // Convert to U/V + if (rg == NULL) { + WebPConvertRGBA32ToUV(tmp_rgb, dst_u, dst_v, uv_width); + } else { + ConvertRowsToUV(tmp_rgb, dst_u, dst_v, uv_width, rg); + } + dst_u += picture->uv_stride; + dst_v += picture->uv_stride; + } + if (height & 1) { // extra last row + const int off = 2 * y * rgb_stride; + int row_has_alpha = has_alpha; + if (use_dsp) { + if (r_ptr < b_ptr) { + WebPConvertRGB24ToY(r_ptr + off, dst_y, width); + } else { + WebPConvertBGR24ToY(b_ptr + off, dst_y, width); + } + } else { + ConvertRowToY(r_ptr + off, g_ptr + off, b_ptr + off, step, + dst_y, width, rg); + } + if (row_has_alpha) { + row_has_alpha &= !WebPExtractAlpha(a_ptr + off, 0, width, 1, dst_a, 0); + } + // Collect averaged R/G/B(/A) + if (!row_has_alpha) { + // Collect averaged R/G/B + AccumulateRGB(r_ptr + off, g_ptr + off, b_ptr + off, + step, /* rgb_stride = */ 0, tmp_rgb, width); + } else { + AccumulateRGBA(r_ptr + off, g_ptr + off, b_ptr + off, a_ptr + off, + /* rgb_stride = */ 0, tmp_rgb, width); + } + if (rg == NULL) { + WebPConvertRGBA32ToUV(tmp_rgb, dst_u, dst_v, uv_width); + } else { + ConvertRowsToUV(tmp_rgb, dst_u, dst_v, uv_width, rg); + } + } + WebPSafeFree(tmp_rgb); + } + return 1; +} + +#undef SUM4 +#undef SUM2 +#undef SUM4ALPHA +#undef SUM2ALPHA + +//------------------------------------------------------------------------------ +// call for ARGB->YUVA conversion + +static int PictureARGBToYUVA(WebPPicture* picture, WebPEncCSP colorspace, + float dithering, int use_iterative_conversion) { + if (picture == NULL) return 0; + if (picture->argb == NULL) { + return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER); + } else if ((colorspace & WEBP_CSP_UV_MASK) != WEBP_YUV420) { + return WebPEncodingSetError(picture, VP8_ENC_ERROR_INVALID_CONFIGURATION); + } else { + const uint8_t* const argb = (const uint8_t*)picture->argb; + const uint8_t* const r = ALPHA_IS_LAST ? argb + 2 : argb + 1; + const uint8_t* const g = ALPHA_IS_LAST ? argb + 1 : argb + 2; + const uint8_t* const b = ALPHA_IS_LAST ? argb + 0 : argb + 3; + const uint8_t* const a = ALPHA_IS_LAST ? argb + 3 : argb + 0; + + picture->colorspace = WEBP_YUV420; + return ImportYUVAFromRGBA(r, g, b, a, 4, 4 * picture->argb_stride, + dithering, use_iterative_conversion, picture); + } +} + +int WebPPictureARGBToYUVADithered(WebPPicture* picture, WebPEncCSP colorspace, + float dithering) { + return PictureARGBToYUVA(picture, colorspace, dithering, 0); +} + +int WebPPictureARGBToYUVA(WebPPicture* picture, WebPEncCSP colorspace) { + return PictureARGBToYUVA(picture, colorspace, 0.f, 0); +} + +int WebPPictureSmartARGBToYUVA(WebPPicture* picture) { + return PictureARGBToYUVA(picture, WEBP_YUV420, 0.f, 1); +} + +//------------------------------------------------------------------------------ +// call for YUVA -> ARGB conversion + +int WebPPictureYUVAToARGB(WebPPicture* picture) { + if (picture == NULL) return 0; + if (picture->y == NULL || picture->u == NULL || picture->v == NULL) { + return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER); + } + if ((picture->colorspace & WEBP_CSP_ALPHA_BIT) && picture->a == NULL) { + return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER); + } + if ((picture->colorspace & WEBP_CSP_UV_MASK) != WEBP_YUV420) { + return WebPEncodingSetError(picture, VP8_ENC_ERROR_INVALID_CONFIGURATION); + } + // Allocate a new argb buffer (discarding the previous one). + if (!WebPPictureAllocARGB(picture, picture->width, picture->height)) return 0; + picture->use_argb = 1; + + // Convert + { + int y; + const int width = picture->width; + const int height = picture->height; + const int argb_stride = 4 * picture->argb_stride; + uint8_t* dst = (uint8_t*)picture->argb; + const uint8_t *cur_u = picture->u, *cur_v = picture->v, *cur_y = picture->y; + WebPUpsampleLinePairFunc upsample = WebPGetLinePairConverter(ALPHA_IS_LAST); + + // First row, with replicated top samples. + upsample(cur_y, NULL, cur_u, cur_v, cur_u, cur_v, dst, NULL, width); + cur_y += picture->y_stride; + dst += argb_stride; + // Center rows. + for (y = 1; y + 1 < height; y += 2) { + const uint8_t* const top_u = cur_u; + const uint8_t* const top_v = cur_v; + cur_u += picture->uv_stride; + cur_v += picture->uv_stride; + upsample(cur_y, cur_y + picture->y_stride, top_u, top_v, cur_u, cur_v, + dst, dst + argb_stride, width); + cur_y += 2 * picture->y_stride; + dst += 2 * argb_stride; + } + // Last row (if needed), with replicated bottom samples. + if (height > 1 && !(height & 1)) { + upsample(cur_y, NULL, cur_u, cur_v, cur_u, cur_v, dst, NULL, width); + } + // Insert alpha values if needed, in replacement for the default 0xff ones. + if (picture->colorspace & WEBP_CSP_ALPHA_BIT) { + for (y = 0; y < height; ++y) { + uint32_t* const argb_dst = picture->argb + y * picture->argb_stride; + const uint8_t* const src = picture->a + y * picture->a_stride; + int x; + for (x = 0; x < width; ++x) { + argb_dst[x] = (argb_dst[x] & 0x00ffffffu) | ((uint32_t)src[x] << 24); + } + } + } + } + return 1; +} + +//------------------------------------------------------------------------------ +// automatic import / conversion + +static int Import(WebPPicture* const picture, + const uint8_t* const rgb, int rgb_stride, + int step, int swap_rb, int import_alpha) { + int y; + const uint8_t* const r_ptr = rgb + (swap_rb ? 2 : 0); + const uint8_t* const g_ptr = rgb + 1; + const uint8_t* const b_ptr = rgb + (swap_rb ? 0 : 2); + const uint8_t* const a_ptr = import_alpha ? rgb + 3 : NULL; + const int width = picture->width; + const int height = picture->height; + + if (!picture->use_argb) { + return ImportYUVAFromRGBA(r_ptr, g_ptr, b_ptr, a_ptr, step, rgb_stride, + 0.f /* no dithering */, 0, picture); + } + if (!WebPPictureAlloc(picture)) return 0; + + VP8EncDspARGBInit(); + + if (import_alpha) { + assert(step == 4); + for (y = 0; y < height; ++y) { + uint32_t* const dst = &picture->argb[y * picture->argb_stride]; + const int offset = y * rgb_stride; + VP8PackARGB(a_ptr + offset, r_ptr + offset, g_ptr + offset, + b_ptr + offset, width, dst); + } + } else { + assert(step >= 3); + for (y = 0; y < height; ++y) { + uint32_t* const dst = &picture->argb[y * picture->argb_stride]; + const int offset = y * rgb_stride; + VP8PackRGB(r_ptr + offset, g_ptr + offset, b_ptr + offset, + width, step, dst); + } + } + return 1; +} + +// Public API + +int WebPPictureImportRGB(WebPPicture* picture, + const uint8_t* rgb, int rgb_stride) { + return (picture != NULL) ? Import(picture, rgb, rgb_stride, 3, 0, 0) : 0; +} + +int WebPPictureImportBGR(WebPPicture* picture, + const uint8_t* rgb, int rgb_stride) { + return (picture != NULL) ? Import(picture, rgb, rgb_stride, 3, 1, 0) : 0; +} + +int WebPPictureImportRGBA(WebPPicture* picture, + const uint8_t* rgba, int rgba_stride) { + return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 0, 1) : 0; +} + +int WebPPictureImportBGRA(WebPPicture* picture, + const uint8_t* rgba, int rgba_stride) { + return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 1, 1) : 0; +} + +int WebPPictureImportRGBX(WebPPicture* picture, + const uint8_t* rgba, int rgba_stride) { + return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 0, 0) : 0; +} + +int WebPPictureImportBGRX(WebPPicture* picture, + const uint8_t* rgba, int rgba_stride) { + return (picture != NULL) ? Import(picture, rgba, rgba_stride, 4, 1, 0) : 0; +} + +//------------------------------------------------------------------------------ diff --git a/drivers/webp/enc/picture_psnr.c b/drivers/webp/enc/picture_psnr.c new file mode 100644 index 0000000000..40214efc95 --- /dev/null +++ b/drivers/webp/enc/picture_psnr.c @@ -0,0 +1,175 @@ +// Copyright 2014 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// WebPPicture tools for measuring distortion +// +// Author: Skal (pascal.massimino@gmail.com) + +#include <math.h> +#include <stdlib.h> + +#include "./vp8enci.h" +#include "../utils/utils.h" + +//------------------------------------------------------------------------------ +// local-min distortion +// +// For every pixel in the *reference* picture, we search for the local best +// match in the compressed image. This is not a symmetrical measure. + +#define RADIUS 2 // search radius. Shouldn't be too large. + +static void AccumulateLSIM(const uint8_t* src, int src_stride, + const uint8_t* ref, int ref_stride, + int w, int h, DistoStats* stats) { + int x, y; + double total_sse = 0.; + for (y = 0; y < h; ++y) { + const int y_0 = (y - RADIUS < 0) ? 0 : y - RADIUS; + const int y_1 = (y + RADIUS + 1 >= h) ? h : y + RADIUS + 1; + for (x = 0; x < w; ++x) { + const int x_0 = (x - RADIUS < 0) ? 0 : x - RADIUS; + const int x_1 = (x + RADIUS + 1 >= w) ? w : x + RADIUS + 1; + double best_sse = 255. * 255.; + const double value = (double)ref[y * ref_stride + x]; + int i, j; + for (j = y_0; j < y_1; ++j) { + const uint8_t* const s = src + j * src_stride; + for (i = x_0; i < x_1; ++i) { + const double diff = s[i] - value; + const double sse = diff * diff; + if (sse < best_sse) best_sse = sse; + } + } + total_sse += best_sse; + } + } + stats->w = w * h; + stats->xm = 0; + stats->ym = 0; + stats->xxm = total_sse; + stats->yym = 0; + stats->xxm = 0; +} +#undef RADIUS + +//------------------------------------------------------------------------------ +// Distortion + +// Max value returned in case of exact similarity. +static const double kMinDistortion_dB = 99.; +static float GetPSNR(const double v) { + return (float)((v > 0.) ? -4.3429448 * log(v / (255 * 255.)) + : kMinDistortion_dB); +} + +int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref, + int type, float result[5]) { + DistoStats stats[5]; + int w, h; + + memset(stats, 0, sizeof(stats)); + + if (src == NULL || ref == NULL || + src->width != ref->width || src->height != ref->height || + src->use_argb != ref->use_argb || result == NULL) { + return 0; + } + w = src->width; + h = src->height; + + if (src->use_argb == 1) { + if (src->argb == NULL || ref->argb == NULL) { + return 0; + } else { + int i, j, c; + uint8_t* tmp1, *tmp2; + uint8_t* const tmp_plane = + (uint8_t*)WebPSafeMalloc(2ULL * w * h, sizeof(*tmp_plane)); + if (tmp_plane == NULL) return 0; + tmp1 = tmp_plane; + tmp2 = tmp_plane + w * h; + for (c = 0; c < 4; ++c) { + for (j = 0; j < h; ++j) { + for (i = 0; i < w; ++i) { + tmp1[j * w + i] = src->argb[i + j * src->argb_stride] >> (c * 8); + tmp2[j * w + i] = ref->argb[i + j * ref->argb_stride] >> (c * 8); + } + } + if (type >= 2) { + AccumulateLSIM(tmp1, w, tmp2, w, w, h, &stats[c]); + } else { + VP8SSIMAccumulatePlane(tmp1, w, tmp2, w, w, h, &stats[c]); + } + } + free(tmp_plane); + } + } else { + int has_alpha, uv_w, uv_h; + if (src->y == NULL || ref->y == NULL || + src->u == NULL || ref->u == NULL || + src->v == NULL || ref->v == NULL) { + return 0; + } + has_alpha = !!(src->colorspace & WEBP_CSP_ALPHA_BIT); + if (has_alpha != !!(ref->colorspace & WEBP_CSP_ALPHA_BIT) || + (has_alpha && (src->a == NULL || ref->a == NULL))) { + return 0; + } + + uv_w = (src->width + 1) >> 1; + uv_h = (src->height + 1) >> 1; + if (type >= 2) { + AccumulateLSIM(src->y, src->y_stride, ref->y, ref->y_stride, + w, h, &stats[0]); + AccumulateLSIM(src->u, src->uv_stride, ref->u, ref->uv_stride, + uv_w, uv_h, &stats[1]); + AccumulateLSIM(src->v, src->uv_stride, ref->v, ref->uv_stride, + uv_w, uv_h, &stats[2]); + if (has_alpha) { + AccumulateLSIM(src->a, src->a_stride, ref->a, ref->a_stride, + w, h, &stats[3]); + } + } else { + VP8SSIMAccumulatePlane(src->y, src->y_stride, + ref->y, ref->y_stride, + w, h, &stats[0]); + VP8SSIMAccumulatePlane(src->u, src->uv_stride, + ref->u, ref->uv_stride, + uv_w, uv_h, &stats[1]); + VP8SSIMAccumulatePlane(src->v, src->uv_stride, + ref->v, ref->uv_stride, + uv_w, uv_h, &stats[2]); + if (has_alpha) { + VP8SSIMAccumulatePlane(src->a, src->a_stride, + ref->a, ref->a_stride, + w, h, &stats[3]); + } + } + } + // Final stat calculations. + { + int c; + for (c = 0; c <= 4; ++c) { + if (type == 1) { + const double v = VP8SSIMGet(&stats[c]); + result[c] = (float)((v < 1.) ? -10.0 * log10(1. - v) + : kMinDistortion_dB); + } else { + const double v = VP8SSIMGetSquaredError(&stats[c]); + result[c] = GetPSNR(v); + } + // Accumulate forward + if (c < 4) VP8SSIMAddStats(&stats[c], &stats[4]); + } + } + return 1; +} + +//------------------------------------------------------------------------------ diff --git a/drivers/webp/enc/picture_rescale.c b/drivers/webp/enc/picture_rescale.c new file mode 100644 index 0000000000..9f19e8e80f --- /dev/null +++ b/drivers/webp/enc/picture_rescale.c @@ -0,0 +1,264 @@ +// Copyright 2014 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// WebPPicture tools: copy, crop, rescaling and view. +// +// Author: Skal (pascal.massimino@gmail.com) + +#include <assert.h> +#include <stdlib.h> + +#include "./vp8enci.h" +#include "../utils/rescaler.h" +#include "../utils/utils.h" + +#define HALVE(x) (((x) + 1) >> 1) + +// Grab the 'specs' (writer, *opaque, width, height...) from 'src' and copy them +// into 'dst'. Mark 'dst' as not owning any memory. +static void PictureGrabSpecs(const WebPPicture* const src, + WebPPicture* const dst) { + assert(src != NULL && dst != NULL); + *dst = *src; + WebPPictureResetBuffers(dst); +} + +//------------------------------------------------------------------------------ + +// Adjust top-left corner to chroma sample position. +static void SnapTopLeftPosition(const WebPPicture* const pic, + int* const left, int* const top) { + if (!pic->use_argb) { + *left &= ~1; + *top &= ~1; + } +} + +// Adjust top-left corner and verify that the sub-rectangle is valid. +static int AdjustAndCheckRectangle(const WebPPicture* const pic, + int* const left, int* const top, + int width, int height) { + SnapTopLeftPosition(pic, left, top); + if ((*left) < 0 || (*top) < 0) return 0; + if (width <= 0 || height <= 0) return 0; + if ((*left) + width > pic->width) return 0; + if ((*top) + height > pic->height) return 0; + return 1; +} + +int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) { + if (src == NULL || dst == NULL) return 0; + if (src == dst) return 1; + + PictureGrabSpecs(src, dst); + if (!WebPPictureAlloc(dst)) return 0; + + if (!src->use_argb) { + WebPCopyPlane(src->y, src->y_stride, + dst->y, dst->y_stride, dst->width, dst->height); + WebPCopyPlane(src->u, src->uv_stride, dst->u, dst->uv_stride, + HALVE(dst->width), HALVE(dst->height)); + WebPCopyPlane(src->v, src->uv_stride, dst->v, dst->uv_stride, + HALVE(dst->width), HALVE(dst->height)); + if (dst->a != NULL) { + WebPCopyPlane(src->a, src->a_stride, + dst->a, dst->a_stride, dst->width, dst->height); + } + } else { + WebPCopyPlane((const uint8_t*)src->argb, 4 * src->argb_stride, + (uint8_t*)dst->argb, 4 * dst->argb_stride, + 4 * dst->width, dst->height); + } + return 1; +} + +int WebPPictureIsView(const WebPPicture* picture) { + if (picture == NULL) return 0; + if (picture->use_argb) { + return (picture->memory_argb_ == NULL); + } + return (picture->memory_ == NULL); +} + +int WebPPictureView(const WebPPicture* src, + int left, int top, int width, int height, + WebPPicture* dst) { + if (src == NULL || dst == NULL) return 0; + + // verify rectangle position. + if (!AdjustAndCheckRectangle(src, &left, &top, width, height)) return 0; + + if (src != dst) { // beware of aliasing! We don't want to leak 'memory_'. + PictureGrabSpecs(src, dst); + } + dst->width = width; + dst->height = height; + if (!src->use_argb) { + dst->y = src->y + top * src->y_stride + left; + dst->u = src->u + (top >> 1) * src->uv_stride + (left >> 1); + dst->v = src->v + (top >> 1) * src->uv_stride + (left >> 1); + dst->y_stride = src->y_stride; + dst->uv_stride = src->uv_stride; + if (src->a != NULL) { + dst->a = src->a + top * src->a_stride + left; + dst->a_stride = src->a_stride; + } + } else { + dst->argb = src->argb + top * src->argb_stride + left; + dst->argb_stride = src->argb_stride; + } + return 1; +} + +//------------------------------------------------------------------------------ +// Picture cropping + +int WebPPictureCrop(WebPPicture* pic, + int left, int top, int width, int height) { + WebPPicture tmp; + + if (pic == NULL) return 0; + if (!AdjustAndCheckRectangle(pic, &left, &top, width, height)) return 0; + + PictureGrabSpecs(pic, &tmp); + tmp.width = width; + tmp.height = height; + if (!WebPPictureAlloc(&tmp)) return 0; + + if (!pic->use_argb) { + const int y_offset = top * pic->y_stride + left; + const int uv_offset = (top / 2) * pic->uv_stride + left / 2; + WebPCopyPlane(pic->y + y_offset, pic->y_stride, + tmp.y, tmp.y_stride, width, height); + WebPCopyPlane(pic->u + uv_offset, pic->uv_stride, + tmp.u, tmp.uv_stride, HALVE(width), HALVE(height)); + WebPCopyPlane(pic->v + uv_offset, pic->uv_stride, + tmp.v, tmp.uv_stride, HALVE(width), HALVE(height)); + + if (tmp.a != NULL) { + const int a_offset = top * pic->a_stride + left; + WebPCopyPlane(pic->a + a_offset, pic->a_stride, + tmp.a, tmp.a_stride, width, height); + } + } else { + const uint8_t* const src = + (const uint8_t*)(pic->argb + top * pic->argb_stride + left); + WebPCopyPlane(src, pic->argb_stride * 4, (uint8_t*)tmp.argb, + tmp.argb_stride * 4, width * 4, height); + } + WebPPictureFree(pic); + *pic = tmp; + return 1; +} + +//------------------------------------------------------------------------------ +// Simple picture rescaler + +static void RescalePlane(const uint8_t* src, + int src_width, int src_height, int src_stride, + uint8_t* dst, + int dst_width, int dst_height, int dst_stride, + rescaler_t* const work, + int num_channels) { + WebPRescaler rescaler; + int y = 0; + WebPRescalerInit(&rescaler, src_width, src_height, + dst, dst_width, dst_height, dst_stride, + num_channels, work); + while (y < src_height) { + y += WebPRescalerImport(&rescaler, src_height - y, + src + y * src_stride, src_stride); + WebPRescalerExport(&rescaler); + } +} + +static void AlphaMultiplyARGB(WebPPicture* const pic, int inverse) { + assert(pic->argb != NULL); + WebPMultARGBRows((uint8_t*)pic->argb, pic->argb_stride * sizeof(*pic->argb), + pic->width, pic->height, inverse); +} + +static void AlphaMultiplyY(WebPPicture* const pic, int inverse) { + if (pic->a != NULL) { + WebPMultRows(pic->y, pic->y_stride, pic->a, pic->a_stride, + pic->width, pic->height, inverse); + } +} + +int WebPPictureRescale(WebPPicture* pic, int width, int height) { + WebPPicture tmp; + int prev_width, prev_height; + rescaler_t* work; + + if (pic == NULL) return 0; + prev_width = pic->width; + prev_height = pic->height; + if (!WebPRescalerGetScaledDimensions( + prev_width, prev_height, &width, &height)) { + return 0; + } + + PictureGrabSpecs(pic, &tmp); + tmp.width = width; + tmp.height = height; + if (!WebPPictureAlloc(&tmp)) return 0; + + if (!pic->use_argb) { + work = (rescaler_t*)WebPSafeMalloc(2ULL * width, sizeof(*work)); + if (work == NULL) { + WebPPictureFree(&tmp); + return 0; + } + // If present, we need to rescale alpha first (for AlphaMultiplyY). + if (pic->a != NULL) { + WebPInitAlphaProcessing(); + RescalePlane(pic->a, prev_width, prev_height, pic->a_stride, + tmp.a, width, height, tmp.a_stride, work, 1); + } + + // We take transparency into account on the luma plane only. That's not + // totally exact blending, but still is a good approximation. + AlphaMultiplyY(pic, 0); + RescalePlane(pic->y, prev_width, prev_height, pic->y_stride, + tmp.y, width, height, tmp.y_stride, work, 1); + AlphaMultiplyY(&tmp, 1); + + RescalePlane(pic->u, + HALVE(prev_width), HALVE(prev_height), pic->uv_stride, + tmp.u, + HALVE(width), HALVE(height), tmp.uv_stride, work, 1); + RescalePlane(pic->v, + HALVE(prev_width), HALVE(prev_height), pic->uv_stride, + tmp.v, + HALVE(width), HALVE(height), tmp.uv_stride, work, 1); + } else { + work = (rescaler_t*)WebPSafeMalloc(2ULL * width * 4, sizeof(*work)); + if (work == NULL) { + WebPPictureFree(&tmp); + return 0; + } + // In order to correctly interpolate colors, we need to apply the alpha + // weighting first (black-matting), scale the RGB values, and remove + // the premultiplication afterward (while preserving the alpha channel). + WebPInitAlphaProcessing(); + AlphaMultiplyARGB(pic, 0); + RescalePlane((const uint8_t*)pic->argb, prev_width, prev_height, + pic->argb_stride * 4, + (uint8_t*)tmp.argb, width, height, + tmp.argb_stride * 4, + work, 4); + AlphaMultiplyARGB(&tmp, 1); + } + WebPPictureFree(pic); + WebPSafeFree(work); + *pic = tmp; + return 1; +} + +//------------------------------------------------------------------------------ diff --git a/drivers/webp/enc/picture_tools.c b/drivers/webp/enc/picture_tools.c new file mode 100644 index 0000000000..7c73646397 --- /dev/null +++ b/drivers/webp/enc/picture_tools.c @@ -0,0 +1,206 @@ +// Copyright 2014 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// WebPPicture tools: alpha handling, etc. +// +// Author: Skal (pascal.massimino@gmail.com) + +#include "./vp8enci.h" +#include "../dsp/yuv.h" + +static WEBP_INLINE uint32_t MakeARGB32(int r, int g, int b) { + return (0xff000000u | (r << 16) | (g << 8) | b); +} + +//------------------------------------------------------------------------------ +// Helper: clean up fully transparent area to help compressibility. + +#define SIZE 8 +#define SIZE2 (SIZE / 2) +static int is_transparent_area(const uint8_t* ptr, int stride, int size) { + int y, x; + for (y = 0; y < size; ++y) { + for (x = 0; x < size; ++x) { + if (ptr[x]) { + return 0; + } + } + ptr += stride; + } + return 1; +} + +static int is_transparent_argb_area(const uint32_t* ptr, int stride, int size) { + int y, x; + for (y = 0; y < size; ++y) { + for (x = 0; x < size; ++x) { + if (ptr[x] & 0xff000000u) { + return 0; + } + } + ptr += stride; + } + return 1; +} + +static void flatten(uint8_t* ptr, int v, int stride, int size) { + int y; + for (y = 0; y < size; ++y) { + memset(ptr, v, size); + ptr += stride; + } +} + +static void flatten_argb(uint32_t* ptr, uint32_t v, int stride, int size) { + int x, y; + for (y = 0; y < size; ++y) { + for (x = 0; x < size; ++x) ptr[x] = v; + ptr += stride; + } +} + +void WebPCleanupTransparentArea(WebPPicture* pic) { + int x, y, w, h; + if (pic == NULL) return; + w = pic->width / SIZE; + h = pic->height / SIZE; + + // note: we ignore the left-overs on right/bottom + if (pic->use_argb) { + uint32_t argb_value = 0; + for (y = 0; y < h; ++y) { + int need_reset = 1; + for (x = 0; x < w; ++x) { + const int off = (y * pic->argb_stride + x) * SIZE; + if (is_transparent_argb_area(pic->argb + off, pic->argb_stride, SIZE)) { + if (need_reset) { + argb_value = pic->argb[off]; + need_reset = 0; + } + flatten_argb(pic->argb + off, argb_value, pic->argb_stride, SIZE); + } else { + need_reset = 1; + } + } + } + } else { + const uint8_t* const a_ptr = pic->a; + int values[3] = { 0 }; + if (a_ptr == NULL) return; // nothing to do + for (y = 0; y < h; ++y) { + int need_reset = 1; + for (x = 0; x < w; ++x) { + const int off_a = (y * pic->a_stride + x) * SIZE; + const int off_y = (y * pic->y_stride + x) * SIZE; + const int off_uv = (y * pic->uv_stride + x) * SIZE2; + if (is_transparent_area(a_ptr + off_a, pic->a_stride, SIZE)) { + if (need_reset) { + values[0] = pic->y[off_y]; + values[1] = pic->u[off_uv]; + values[2] = pic->v[off_uv]; + need_reset = 0; + } + flatten(pic->y + off_y, values[0], pic->y_stride, SIZE); + flatten(pic->u + off_uv, values[1], pic->uv_stride, SIZE2); + flatten(pic->v + off_uv, values[2], pic->uv_stride, SIZE2); + } else { + need_reset = 1; + } + } + } + } +} + +#undef SIZE +#undef SIZE2 + +//------------------------------------------------------------------------------ +// Blend color and remove transparency info + +#define BLEND(V0, V1, ALPHA) \ + ((((V0) * (255 - (ALPHA)) + (V1) * (ALPHA)) * 0x101) >> 16) +#define BLEND_10BIT(V0, V1, ALPHA) \ + ((((V0) * (1020 - (ALPHA)) + (V1) * (ALPHA)) * 0x101) >> 18) + +void WebPBlendAlpha(WebPPicture* pic, uint32_t background_rgb) { + const int red = (background_rgb >> 16) & 0xff; + const int green = (background_rgb >> 8) & 0xff; + const int blue = (background_rgb >> 0) & 0xff; + int x, y; + if (pic == NULL) return; + if (!pic->use_argb) { + const int uv_width = (pic->width >> 1); // omit last pixel during u/v loop + const int Y0 = VP8RGBToY(red, green, blue, YUV_HALF); + // VP8RGBToU/V expects the u/v values summed over four pixels + const int U0 = VP8RGBToU(4 * red, 4 * green, 4 * blue, 4 * YUV_HALF); + const int V0 = VP8RGBToV(4 * red, 4 * green, 4 * blue, 4 * YUV_HALF); + const int has_alpha = pic->colorspace & WEBP_CSP_ALPHA_BIT; + if (!has_alpha || pic->a == NULL) return; // nothing to do + for (y = 0; y < pic->height; ++y) { + // Luma blending + uint8_t* const y_ptr = pic->y + y * pic->y_stride; + uint8_t* const a_ptr = pic->a + y * pic->a_stride; + for (x = 0; x < pic->width; ++x) { + const int alpha = a_ptr[x]; + if (alpha < 0xff) { + y_ptr[x] = BLEND(Y0, y_ptr[x], a_ptr[x]); + } + } + // Chroma blending every even line + if ((y & 1) == 0) { + uint8_t* const u = pic->u + (y >> 1) * pic->uv_stride; + uint8_t* const v = pic->v + (y >> 1) * pic->uv_stride; + uint8_t* const a_ptr2 = + (y + 1 == pic->height) ? a_ptr : a_ptr + pic->a_stride; + for (x = 0; x < uv_width; ++x) { + // Average four alpha values into a single blending weight. + // TODO(skal): might lead to visible contouring. Can we do better? + const int alpha = + a_ptr[2 * x + 0] + a_ptr[2 * x + 1] + + a_ptr2[2 * x + 0] + a_ptr2[2 * x + 1]; + u[x] = BLEND_10BIT(U0, u[x], alpha); + v[x] = BLEND_10BIT(V0, v[x], alpha); + } + if (pic->width & 1) { // rightmost pixel + const int alpha = 2 * (a_ptr[2 * x + 0] + a_ptr2[2 * x + 0]); + u[x] = BLEND_10BIT(U0, u[x], alpha); + v[x] = BLEND_10BIT(V0, v[x], alpha); + } + } + memset(a_ptr, 0xff, pic->width); + } + } else { + uint32_t* argb = pic->argb; + const uint32_t background = MakeARGB32(red, green, blue); + for (y = 0; y < pic->height; ++y) { + for (x = 0; x < pic->width; ++x) { + const int alpha = (argb[x] >> 24) & 0xff; + if (alpha != 0xff) { + if (alpha > 0) { + int r = (argb[x] >> 16) & 0xff; + int g = (argb[x] >> 8) & 0xff; + int b = (argb[x] >> 0) & 0xff; + r = BLEND(red, r, alpha); + g = BLEND(green, g, alpha); + b = BLEND(blue, b, alpha); + argb[x] = MakeARGB32(r, g, b); + } else { + argb[x] = background; + } + } + } + argb += pic->argb_stride; + } + } +} + +#undef BLEND +#undef BLEND_10BIT + +//------------------------------------------------------------------------------ diff --git a/drivers/webp/enc/token.c b/drivers/webp/enc/token.c new file mode 100644 index 0000000000..e73256b37e --- /dev/null +++ b/drivers/webp/enc/token.c @@ -0,0 +1,285 @@ +// Copyright 2011 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. +// ----------------------------------------------------------------------------- +// +// Paginated token buffer +// +// A 'token' is a bit value associated with a probability, either fixed +// or a later-to-be-determined after statistics have been collected. +// For dynamic probability, we just record the slot id (idx) for the probability +// value in the final probability array (uint8_t* probas in VP8EmitTokens). +// +// Author: Skal (pascal.massimino@gmail.com) + +#include <assert.h> +#include <stdlib.h> +#include <string.h> + +#include "./cost.h" +#include "./vp8enci.h" +#include "../utils/utils.h" + +#if !defined(DISABLE_TOKEN_BUFFER) + +// we use pages to reduce the number of memcpy() +#define MIN_PAGE_SIZE 8192 // minimum number of token per page +#define FIXED_PROBA_BIT (1u << 14) + +typedef uint16_t token_t; // bit #15: bit value + // bit #14: flags for constant proba or idx + // bits #0..13: slot or constant proba +struct VP8Tokens { + VP8Tokens* next_; // pointer to next page +}; +// Token data is located in memory just after the next_ field. +// This macro is used to return their address and hide the trick. +#define TOKEN_DATA(p) ((const token_t*)&(p)[1]) + +//------------------------------------------------------------------------------ + +void VP8TBufferInit(VP8TBuffer* const b, int page_size) { + b->tokens_ = NULL; + b->pages_ = NULL; + b->last_page_ = &b->pages_; + b->left_ = 0; + b->page_size_ = (page_size < MIN_PAGE_SIZE) ? MIN_PAGE_SIZE : page_size; + b->error_ = 0; +} + +void VP8TBufferClear(VP8TBuffer* const b) { + if (b != NULL) { + VP8Tokens* p = b->pages_; + while (p != NULL) { + VP8Tokens* const next = p->next_; + WebPSafeFree(p); + p = next; + } + VP8TBufferInit(b, b->page_size_); + } +} + +static int TBufferNewPage(VP8TBuffer* const b) { + VP8Tokens* page = NULL; + if (!b->error_) { + const size_t size = sizeof(*page) + b->page_size_ * sizeof(token_t); + page = (VP8Tokens*)WebPSafeMalloc(1ULL, size); + } + if (page == NULL) { + b->error_ = 1; + return 0; + } + page->next_ = NULL; + + *b->last_page_ = page; + b->last_page_ = &page->next_; + b->left_ = b->page_size_; + b->tokens_ = (token_t*)TOKEN_DATA(page); + return 1; +} + +//------------------------------------------------------------------------------ + +#define TOKEN_ID(t, b, ctx) \ + (NUM_PROBAS * ((ctx) + NUM_CTX * ((b) + NUM_BANDS * (t)))) + +static WEBP_INLINE uint32_t AddToken(VP8TBuffer* const b, + uint32_t bit, uint32_t proba_idx) { + assert(proba_idx < FIXED_PROBA_BIT); + assert(bit <= 1); + if (b->left_ > 0 || TBufferNewPage(b)) { + const int slot = --b->left_; + b->tokens_[slot] = (bit << 15) | proba_idx; + } + return bit; +} + +static WEBP_INLINE void AddConstantToken(VP8TBuffer* const b, + uint32_t bit, uint32_t proba) { + assert(proba < 256); + assert(bit <= 1); + if (b->left_ > 0 || TBufferNewPage(b)) { + const int slot = --b->left_; + b->tokens_[slot] = (bit << 15) | FIXED_PROBA_BIT | proba; + } +} + +int VP8RecordCoeffTokens(const int ctx, const int coeff_type, + int first, int last, + const int16_t* const coeffs, + VP8TBuffer* const tokens) { + int n = first; + uint32_t base_id = TOKEN_ID(coeff_type, n, ctx); + if (!AddToken(tokens, last >= 0, base_id + 0)) { + return 0; + } + + while (n < 16) { + const int c = coeffs[n++]; + const int sign = c < 0; + const uint32_t v = sign ? -c : c; + if (!AddToken(tokens, v != 0, base_id + 1)) { + base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 0); // ctx=0 + continue; + } + if (!AddToken(tokens, v > 1, base_id + 2)) { + base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 1); // ctx=1 + } else { + if (!AddToken(tokens, v > 4, base_id + 3)) { + if (AddToken(tokens, v != 2, base_id + 4)) + AddToken(tokens, v == 4, base_id + 5); + } else if (!AddToken(tokens, v > 10, base_id + 6)) { + if (!AddToken(tokens, v > 6, base_id + 7)) { + AddConstantToken(tokens, v == 6, 159); + } else { + AddConstantToken(tokens, v >= 9, 165); + AddConstantToken(tokens, !(v & 1), 145); + } + } else { + int mask; + const uint8_t* tab; + uint32_t residue = v - 3; + if (residue < (8 << 1)) { // VP8Cat3 (3b) + AddToken(tokens, 0, base_id + 8); + AddToken(tokens, 0, base_id + 9); + residue -= (8 << 0); + mask = 1 << 2; + tab = VP8Cat3; + } else if (residue < (8 << 2)) { // VP8Cat4 (4b) + AddToken(tokens, 0, base_id + 8); + AddToken(tokens, 1, base_id + 9); + residue -= (8 << 1); + mask = 1 << 3; + tab = VP8Cat4; + } else if (residue < (8 << 3)) { // VP8Cat5 (5b) + AddToken(tokens, 1, base_id + 8); + AddToken(tokens, 0, base_id + 10); + residue -= (8 << 2); + mask = 1 << 4; + tab = VP8Cat5; + } else { // VP8Cat6 (11b) + AddToken(tokens, 1, base_id + 8); + AddToken(tokens, 1, base_id + 10); + residue -= (8 << 3); + mask = 1 << 10; + tab = VP8Cat6; + } + while (mask) { + AddConstantToken(tokens, !!(residue & mask), *tab++); + mask >>= 1; + } + } + base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 2); // ctx=2 + } + AddConstantToken(tokens, sign, 128); + if (n == 16 || !AddToken(tokens, n <= last, base_id + 0)) { + return 1; // EOB + } + } + return 1; +} + +#undef TOKEN_ID + +//------------------------------------------------------------------------------ +// This function works, but isn't currently used. Saved for later. + +#if 0 + +static void Record(int bit, proba_t* const stats) { + proba_t p = *stats; + if (p >= 0xffff0000u) { // an overflow is inbound. + p = ((p + 1u) >> 1) & 0x7fff7fffu; // -> divide the stats by 2. + } + // record bit count (lower 16 bits) and increment total count (upper 16 bits). + p += 0x00010000u + bit; + *stats = p; +} + +void VP8TokenToStats(const VP8TBuffer* const b, proba_t* const stats) { + const VP8Tokens* p = b->pages_; + while (p != NULL) { + const int N = (p->next_ == NULL) ? b->left_ : 0; + int n = MAX_NUM_TOKEN; + const token_t* const tokens = TOKEN_DATA(p); + while (n-- > N) { + const token_t token = tokens[n]; + if (!(token & FIXED_PROBA_BIT)) { + Record((token >> 15) & 1, stats + (token & 0x3fffu)); + } + } + p = p->next_; + } +} + +#endif // 0 + +//------------------------------------------------------------------------------ +// Final coding pass, with known probabilities + +int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw, + const uint8_t* const probas, int final_pass) { + const VP8Tokens* p = b->pages_; + assert(!b->error_); + while (p != NULL) { + const VP8Tokens* const next = p->next_; + const int N = (next == NULL) ? b->left_ : 0; + int n = b->page_size_; + const token_t* const tokens = TOKEN_DATA(p); + while (n-- > N) { + const token_t token = tokens[n]; + const int bit = (token >> 15) & 1; + if (token & FIXED_PROBA_BIT) { + VP8PutBit(bw, bit, token & 0xffu); // constant proba + } else { + VP8PutBit(bw, bit, probas[token & 0x3fffu]); + } + } + if (final_pass) WebPSafeFree((void*)p); + p = next; + } + if (final_pass) b->pages_ = NULL; + return 1; +} + +// Size estimation +size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas) { + size_t size = 0; + const VP8Tokens* p = b->pages_; + assert(!b->error_); + while (p != NULL) { + const VP8Tokens* const next = p->next_; + const int N = (next == NULL) ? b->left_ : 0; + int n = b->page_size_; + const token_t* const tokens = TOKEN_DATA(p); + while (n-- > N) { + const token_t token = tokens[n]; + const int bit = token & (1 << 15); + if (token & FIXED_PROBA_BIT) { + size += VP8BitCost(bit, token & 0xffu); + } else { + size += VP8BitCost(bit, probas[token & 0x3fffu]); + } + } + p = next; + } + return size; +} + +//------------------------------------------------------------------------------ + +#else // DISABLE_TOKEN_BUFFER + +void VP8TBufferInit(VP8TBuffer* const b) { + (void)b; +} +void VP8TBufferClear(VP8TBuffer* const b) { + (void)b; +} + +#endif // !DISABLE_TOKEN_BUFFER + |