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-rw-r--r--thirdparty/libwebp/utils/quant_levels_dec_utils.c284
1 files changed, 0 insertions, 284 deletions
diff --git a/thirdparty/libwebp/utils/quant_levels_dec_utils.c b/thirdparty/libwebp/utils/quant_levels_dec_utils.c
deleted file mode 100644
index d4d23d3147..0000000000
--- a/thirdparty/libwebp/utils/quant_levels_dec_utils.c
+++ /dev/null
@@ -1,284 +0,0 @@
-// Copyright 2013 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.
-// -----------------------------------------------------------------------------
-//
-// Implement gradient smoothing: we replace a current alpha value by its
-// surrounding average if it's close enough (that is: the change will be less
-// than the minimum distance between two quantized level).
-// We use sliding window for computing the 2d moving average.
-//
-// Author: Skal (pascal.massimino@gmail.com)
-
-#include "./quant_levels_dec_utils.h"
-
-#include <string.h> // for memset
-
-#include "./utils.h"
-
-// #define USE_DITHERING // uncomment to enable ordered dithering (not vital)
-
-#define FIX 16 // fix-point precision for averaging
-#define LFIX 2 // extra precision for look-up table
-#define LUT_SIZE ((1 << (8 + LFIX)) - 1) // look-up table size
-
-#if defined(USE_DITHERING)
-
-#define DFIX 4 // extra precision for ordered dithering
-#define DSIZE 4 // dithering size (must be a power of two)
-// cf. http://en.wikipedia.org/wiki/Ordered_dithering
-static const uint8_t kOrderedDither[DSIZE][DSIZE] = {
- { 0, 8, 2, 10 }, // coefficients are in DFIX fixed-point precision
- { 12, 4, 14, 6 },
- { 3, 11, 1, 9 },
- { 15, 7, 13, 5 }
-};
-
-#else
-#define DFIX 0
-#endif
-
-typedef struct {
- int width_, height_; // dimension
- int stride_; // stride in bytes
- int row_; // current input row being processed
- uint8_t* src_; // input pointer
- uint8_t* dst_; // output pointer
-
- int radius_; // filter radius (=delay)
- int scale_; // normalization factor, in FIX bits precision
-
- void* mem_; // all memory
-
- // various scratch buffers
- uint16_t* start_;
- uint16_t* cur_;
- uint16_t* end_;
- uint16_t* top_;
- uint16_t* average_;
-
- // input levels distribution
- int num_levels_; // number of quantized levels
- int min_, max_; // min and max level values
- int min_level_dist_; // smallest distance between two consecutive levels
-
- int16_t* correction_; // size = 1 + 2*LUT_SIZE -> ~4k memory
-} SmoothParams;
-
-//------------------------------------------------------------------------------
-
-#define CLIP_MASK (int)(~0U << (8 + DFIX))
-static WEBP_INLINE uint8_t clip_8b(int v) {
- return (!(v & CLIP_MASK)) ? (uint8_t)(v >> DFIX) : (v < 0) ? 0u : 255u;
-}
-
-// vertical accumulation
-static void VFilter(SmoothParams* const p) {
- const uint8_t* src = p->src_;
- const int w = p->width_;
- uint16_t* const cur = p->cur_;
- const uint16_t* const top = p->top_;
- uint16_t* const out = p->end_;
- uint16_t sum = 0; // all arithmetic is modulo 16bit
- int x;
-
- for (x = 0; x < w; ++x) {
- uint16_t new_value;
- sum += src[x];
- new_value = top[x] + sum;
- out[x] = new_value - cur[x]; // vertical sum of 'r' pixels.
- cur[x] = new_value;
- }
- // move input pointers one row down
- p->top_ = p->cur_;
- p->cur_ += w;
- if (p->cur_ == p->end_) p->cur_ = p->start_; // roll-over
- // We replicate edges, as it's somewhat easier as a boundary condition.
- // That's why we don't update the 'src' pointer on top/bottom area:
- if (p->row_ >= 0 && p->row_ < p->height_ - 1) {
- p->src_ += p->stride_;
- }
-}
-
-// horizontal accumulation. We use mirror replication of missing pixels, as it's
-// a little easier to implement (surprisingly).
-static void HFilter(SmoothParams* const p) {
- const uint16_t* const in = p->end_;
- uint16_t* const out = p->average_;
- const uint32_t scale = p->scale_;
- const int w = p->width_;
- const int r = p->radius_;
-
- int x;
- for (x = 0; x <= r; ++x) { // left mirroring
- const uint16_t delta = in[x + r - 1] + in[r - x];
- out[x] = (delta * scale) >> FIX;
- }
- for (; x < w - r; ++x) { // bulk middle run
- const uint16_t delta = in[x + r] - in[x - r - 1];
- out[x] = (delta * scale) >> FIX;
- }
- for (; x < w; ++x) { // right mirroring
- const uint16_t delta =
- 2 * in[w - 1] - in[2 * w - 2 - r - x] - in[x - r - 1];
- out[x] = (delta * scale) >> FIX;
- }
-}
-
-// emit one filtered output row
-static void ApplyFilter(SmoothParams* const p) {
- const uint16_t* const average = p->average_;
- const int w = p->width_;
- const int16_t* const correction = p->correction_;
-#if defined(USE_DITHERING)
- const uint8_t* const dither = kOrderedDither[p->row_ % DSIZE];
-#endif
- uint8_t* const dst = p->dst_;
- int x;
- for (x = 0; x < w; ++x) {
- const int v = dst[x];
- if (v < p->max_ && v > p->min_) {
- const int c = (v << DFIX) + correction[average[x] - (v << LFIX)];
-#if defined(USE_DITHERING)
- dst[x] = clip_8b(c + dither[x % DSIZE]);
-#else
- dst[x] = clip_8b(c);
-#endif
- }
- }
- p->dst_ += p->stride_; // advance output pointer
-}
-
-//------------------------------------------------------------------------------
-// Initialize correction table
-
-static void InitCorrectionLUT(int16_t* const lut, int min_dist) {
- // The correction curve is:
- // f(x) = x for x <= threshold2
- // f(x) = 0 for x >= threshold1
- // and a linear interpolation for range x=[threshold2, threshold1]
- // (along with f(-x) = -f(x) symmetry).
- // Note that: threshold2 = 3/4 * threshold1
- const int threshold1 = min_dist << LFIX;
- const int threshold2 = (3 * threshold1) >> 2;
- const int max_threshold = threshold2 << DFIX;
- const int delta = threshold1 - threshold2;
- int i;
- for (i = 1; i <= LUT_SIZE; ++i) {
- int c = (i <= threshold2) ? (i << DFIX)
- : (i < threshold1) ? max_threshold * (threshold1 - i) / delta
- : 0;
- c >>= LFIX;
- lut[+i] = +c;
- lut[-i] = -c;
- }
- lut[0] = 0;
-}
-
-static void CountLevels(SmoothParams* const p) {
- int i, j, last_level;
- uint8_t used_levels[256] = { 0 };
- const uint8_t* data = p->src_;
- p->min_ = 255;
- p->max_ = 0;
- for (j = 0; j < p->height_; ++j) {
- for (i = 0; i < p->width_; ++i) {
- const int v = data[i];
- if (v < p->min_) p->min_ = v;
- if (v > p->max_) p->max_ = v;
- used_levels[v] = 1;
- }
- data += p->stride_;
- }
- // Compute the mininum distance between two non-zero levels.
- p->min_level_dist_ = p->max_ - p->min_;
- last_level = -1;
- for (i = 0; i < 256; ++i) {
- if (used_levels[i]) {
- ++p->num_levels_;
- if (last_level >= 0) {
- const int level_dist = i - last_level;
- if (level_dist < p->min_level_dist_) {
- p->min_level_dist_ = level_dist;
- }
- }
- last_level = i;
- }
- }
-}
-
-// Initialize all params.
-static int InitParams(uint8_t* const data, int width, int height, int stride,
- int radius, SmoothParams* const p) {
- const int R = 2 * radius + 1; // total size of the kernel
-
- const size_t size_scratch_m = (R + 1) * width * sizeof(*p->start_);
- const size_t size_m = width * sizeof(*p->average_);
- const size_t size_lut = (1 + 2 * LUT_SIZE) * sizeof(*p->correction_);
- const size_t total_size = size_scratch_m + size_m + size_lut;
- uint8_t* mem = (uint8_t*)WebPSafeMalloc(1U, total_size);
-
- if (mem == NULL) return 0;
- p->mem_ = (void*)mem;
-
- p->start_ = (uint16_t*)mem;
- p->cur_ = p->start_;
- p->end_ = p->start_ + R * width;
- p->top_ = p->end_ - width;
- memset(p->top_, 0, width * sizeof(*p->top_));
- mem += size_scratch_m;
-
- p->average_ = (uint16_t*)mem;
- mem += size_m;
-
- p->width_ = width;
- p->height_ = height;
- p->stride_ = stride;
- p->src_ = data;
- p->dst_ = data;
- p->radius_ = radius;
- p->scale_ = (1 << (FIX + LFIX)) / (R * R); // normalization constant
- p->row_ = -radius;
-
- // analyze the input distribution so we can best-fit the threshold
- CountLevels(p);
-
- // correction table
- p->correction_ = ((int16_t*)mem) + LUT_SIZE;
- InitCorrectionLUT(p->correction_, p->min_level_dist_);
-
- return 1;
-}
-
-static void CleanupParams(SmoothParams* const p) {
- WebPSafeFree(p->mem_);
-}
-
-int WebPDequantizeLevels(uint8_t* const data, int width, int height, int stride,
- int strength) {
- const int radius = 4 * strength / 100;
- if (strength < 0 || strength > 100) return 0;
- if (data == NULL || width <= 0 || height <= 0) return 0; // bad params
- if (radius > 0) {
- SmoothParams p;
- memset(&p, 0, sizeof(p));
- if (!InitParams(data, width, height, stride, radius, &p)) return 0;
- if (p.num_levels_ > 2) {
- for (; p.row_ < p.height_; ++p.row_) {
- VFilter(&p); // accumulate average of input
- // Need to wait few rows in order to prime the filter,
- // before emitting some output.
- if (p.row_ >= p.radius_) {
- HFilter(&p);
- ApplyFilter(&p);
- }
- }
- }
- CleanupParams(&p);
- }
- return 1;
-}
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