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Diffstat (limited to 'drivers/webpold/dsp/lossless.c')
| -rw-r--r-- | drivers/webpold/dsp/lossless.c | 1138 |
1 files changed, 0 insertions, 1138 deletions
diff --git a/drivers/webpold/dsp/lossless.c b/drivers/webpold/dsp/lossless.c deleted file mode 100644 index 62a6b7b15a..0000000000 --- a/drivers/webpold/dsp/lossless.c +++ /dev/null @@ -1,1138 +0,0 @@ -// Copyright 2012 Google Inc. All Rights Reserved. -// -// This code is licensed under the same terms as WebM: -// Software License Agreement: http://www.webmproject.org/license/software/ -// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ -// ----------------------------------------------------------------------------- -// -// Image transforms and color space conversion methods for lossless decoder. -// -// Authors: Vikas Arora (vikaas.arora@gmail.com) -// Jyrki Alakuijala (jyrki@google.com) -// Urvang Joshi (urvang@google.com) - -#if defined(__cplusplus) || defined(c_plusplus) -extern "C" { -#endif - -#include <math.h> -#include <stdlib.h> -#include "./lossless.h" -#include "../dec/vp8li.h" -#include "../dsp/yuv.h" -#include "../dsp/dsp.h" -#include "../enc/histogram.h" - -#define MAX_DIFF_COST (1e30f) - -// lookup table for small values of log2(int) -#define APPROX_LOG_MAX 4096 -#define LOG_2_RECIPROCAL 1.44269504088896338700465094007086 -#define LOG_LOOKUP_IDX_MAX 256 -static const float kLog2Table[LOG_LOOKUP_IDX_MAX] = { - 0.0000000000000000f, 0.0000000000000000f, - 1.0000000000000000f, 1.5849625007211560f, - 2.0000000000000000f, 2.3219280948873621f, - 2.5849625007211560f, 2.8073549220576041f, - 3.0000000000000000f, 3.1699250014423121f, - 3.3219280948873621f, 3.4594316186372973f, - 3.5849625007211560f, 3.7004397181410921f, - 3.8073549220576041f, 3.9068905956085187f, - 4.0000000000000000f, 4.0874628412503390f, - 4.1699250014423121f, 4.2479275134435852f, - 4.3219280948873626f, 4.3923174227787606f, - 4.4594316186372973f, 4.5235619560570130f, - 4.5849625007211560f, 4.6438561897747243f, - 4.7004397181410917f, 4.7548875021634682f, - 4.8073549220576037f, 4.8579809951275718f, - 4.9068905956085187f, 4.9541963103868749f, - 5.0000000000000000f, 5.0443941193584533f, - 5.0874628412503390f, 5.1292830169449663f, - 5.1699250014423121f, 5.2094533656289501f, - 5.2479275134435852f, 5.2854022188622487f, - 5.3219280948873626f, 5.3575520046180837f, - 5.3923174227787606f, 5.4262647547020979f, - 5.4594316186372973f, 5.4918530963296747f, - 5.5235619560570130f, 5.5545888516776376f, - 5.5849625007211560f, 5.6147098441152083f, - 5.6438561897747243f, 5.6724253419714951f, - 5.7004397181410917f, 5.7279204545631987f, - 5.7548875021634682f, 5.7813597135246599f, - 5.8073549220576037f, 5.8328900141647412f, - 5.8579809951275718f, 5.8826430493618415f, - 5.9068905956085187f, 5.9307373375628866f, - 5.9541963103868749f, 5.9772799234999167f, - 6.0000000000000000f, 6.0223678130284543f, - 6.0443941193584533f, 6.0660891904577720f, - 6.0874628412503390f, 6.1085244567781691f, - 6.1292830169449663f, 6.1497471195046822f, - 6.1699250014423121f, 6.1898245588800175f, - 6.2094533656289501f, 6.2288186904958804f, - 6.2479275134435852f, 6.2667865406949010f, - 6.2854022188622487f, 6.3037807481771030f, - 6.3219280948873626f, 6.3398500028846243f, - 6.3575520046180837f, 6.3750394313469245f, - 6.3923174227787606f, 6.4093909361377017f, - 6.4262647547020979f, 6.4429434958487279f, - 6.4594316186372973f, 6.4757334309663976f, - 6.4918530963296747f, 6.5077946401986963f, - 6.5235619560570130f, 6.5391588111080309f, - 6.5545888516776376f, 6.5698556083309478f, - 6.5849625007211560f, 6.5999128421871278f, - 6.6147098441152083f, 6.6293566200796094f, - 6.6438561897747243f, 6.6582114827517946f, - 6.6724253419714951f, 6.6865005271832185f, - 6.7004397181410917f, 6.7142455176661224f, - 6.7279204545631987f, 6.7414669864011464f, - 6.7548875021634682f, 6.7681843247769259f, - 6.7813597135246599f, 6.7944158663501061f, - 6.8073549220576037f, 6.8201789624151878f, - 6.8328900141647412f, 6.8454900509443747f, - 6.8579809951275718f, 6.8703647195834047f, - 6.8826430493618415f, 6.8948177633079437f, - 6.9068905956085187f, 6.9188632372745946f, - 6.9307373375628866f, 6.9425145053392398f, - 6.9541963103868749f, 6.9657842846620869f, - 6.9772799234999167f, 6.9886846867721654f, - 7.0000000000000000f, 7.0112272554232539f, - 7.0223678130284543f, 7.0334230015374501f, - 7.0443941193584533f, 7.0552824355011898f, - 7.0660891904577720f, 7.0768155970508308f, - 7.0874628412503390f, 7.0980320829605263f, - 7.1085244567781691f, 7.1189410727235076f, - 7.1292830169449663f, 7.1395513523987936f, - 7.1497471195046822f, 7.1598713367783890f, - 7.1699250014423121f, 7.1799090900149344f, - 7.1898245588800175f, 7.1996723448363644f, - 7.2094533656289501f, 7.2191685204621611f, - 7.2288186904958804f, 7.2384047393250785f, - 7.2479275134435852f, 7.2573878426926521f, - 7.2667865406949010f, 7.2761244052742375f, - 7.2854022188622487f, 7.2946207488916270f, - 7.3037807481771030f, 7.3128829552843557f, - 7.3219280948873626f, 7.3309168781146167f, - 7.3398500028846243f, 7.3487281542310771f, - 7.3575520046180837f, 7.3663222142458160f, - 7.3750394313469245f, 7.3837042924740519f, - 7.3923174227787606f, 7.4008794362821843f, - 7.4093909361377017f, 7.4178525148858982f, - 7.4262647547020979f, 7.4346282276367245f, - 7.4429434958487279f, 7.4512111118323289f, - 7.4594316186372973f, 7.4676055500829976f, - 7.4757334309663976f, 7.4838157772642563f, - 7.4918530963296747f, 7.4998458870832056f, - 7.5077946401986963f, 7.5156998382840427f, - 7.5235619560570130f, 7.5313814605163118f, - 7.5391588111080309f, 7.5468944598876364f, - 7.5545888516776376f, 7.5622424242210728f, - 7.5698556083309478f, 7.5774288280357486f, - 7.5849625007211560f, 7.5924570372680806f, - 7.5999128421871278f, 7.6073303137496104f, - 7.6147098441152083f, 7.6220518194563764f, - 7.6293566200796094f, 7.6366246205436487f, - 7.6438561897747243f, 7.6510516911789281f, - 7.6582114827517946f, 7.6653359171851764f, - 7.6724253419714951f, 7.6794800995054464f, - 7.6865005271832185f, 7.6934869574993252f, - 7.7004397181410917f, 7.7073591320808825f, - 7.7142455176661224f, 7.7210991887071855f, - 7.7279204545631987f, 7.7347096202258383f, - 7.7414669864011464f, 7.7481928495894605f, - 7.7548875021634682f, 7.7615512324444795f, - 7.7681843247769259f, 7.7747870596011736f, - 7.7813597135246599f, 7.7879025593914317f, - 7.7944158663501061f, 7.8008998999203047f, - 7.8073549220576037f, 7.8137811912170374f, - 7.8201789624151878f, 7.8265484872909150f, - 7.8328900141647412f, 7.8392037880969436f, - 7.8454900509443747f, 7.8517490414160571f, - 7.8579809951275718f, 7.8641861446542797f, - 7.8703647195834047f, 7.8765169465649993f, - 7.8826430493618415f, 7.8887432488982591f, - 7.8948177633079437f, 7.9008668079807486f, - 7.9068905956085187f, 7.9128893362299619f, - 7.9188632372745946f, 7.9248125036057812f, - 7.9307373375628866f, 7.9366379390025709f, - 7.9425145053392398f, 7.9483672315846778f, - 7.9541963103868749f, 7.9600019320680805f, - 7.9657842846620869f, 7.9715435539507719f, - 7.9772799234999167f, 7.9829935746943103f, - 7.9886846867721654f, 7.9943534368588577f -}; - -float VP8LFastLog2(int v) { - if (v < LOG_LOOKUP_IDX_MAX) { - return kLog2Table[v]; - } else if (v < APPROX_LOG_MAX) { - int log_cnt = 0; - while (v >= LOG_LOOKUP_IDX_MAX) { - ++log_cnt; - v = v >> 1; - } - return kLog2Table[v] + (float)log_cnt; - } else { - return (float)(LOG_2_RECIPROCAL * log((double)v)); - } -} - -//------------------------------------------------------------------------------ -// Image transforms. - -// 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 Average2(uint32_t a0, uint32_t a1) { - return (((a0 ^ a1) & 0xfefefefeL) >> 1) + (a0 & a1); -} - -static WEBP_INLINE uint32_t Average3(uint32_t a0, uint32_t a1, uint32_t a2) { - return Average2(Average2(a0, a2), a1); -} - -static WEBP_INLINE uint32_t Average4(uint32_t a0, uint32_t a1, - uint32_t a2, uint32_t a3) { - return Average2(Average2(a0, a1), Average2(a2, a3)); -} - -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; -} - -static WEBP_INLINE int AddSubtractComponentFull(int a, int b, int c) { - return Clip255(a + b - c); -} - -static WEBP_INLINE uint32_t ClampedAddSubtractFull(uint32_t c0, uint32_t c1, - uint32_t c2) { - const int a = AddSubtractComponentFull(c0 >> 24, c1 >> 24, c2 >> 24); - const int r = AddSubtractComponentFull((c0 >> 16) & 0xff, - (c1 >> 16) & 0xff, - (c2 >> 16) & 0xff); - const int g = AddSubtractComponentFull((c0 >> 8) & 0xff, - (c1 >> 8) & 0xff, - (c2 >> 8) & 0xff); - const int b = AddSubtractComponentFull(c0 & 0xff, c1 & 0xff, c2 & 0xff); - return (a << 24) | (r << 16) | (g << 8) | b; -} - -static WEBP_INLINE int AddSubtractComponentHalf(int a, int b) { - return Clip255(a + (a - b) / 2); -} - -static WEBP_INLINE uint32_t ClampedAddSubtractHalf(uint32_t c0, uint32_t c1, - uint32_t c2) { - const uint32_t ave = Average2(c0, c1); - const int a = AddSubtractComponentHalf(ave >> 24, c2 >> 24); - const int r = AddSubtractComponentHalf((ave >> 16) & 0xff, (c2 >> 16) & 0xff); - const int g = AddSubtractComponentHalf((ave >> 8) & 0xff, (c2 >> 8) & 0xff); - const int b = AddSubtractComponentHalf((ave >> 0) & 0xff, (c2 >> 0) & 0xff); - return (a << 24) | (r << 16) | (g << 8) | b; -} - -static WEBP_INLINE int Sub3(int a, int b, int c) { - const int pa = b - c; - const int pb = a - c; - return abs(pa) - abs(pb); -} - -static WEBP_INLINE uint32_t Select(uint32_t a, uint32_t b, uint32_t c) { - const int pa_minus_pb = - Sub3((a >> 24) , (b >> 24) , (c >> 24) ) + - Sub3((a >> 16) & 0xff, (b >> 16) & 0xff, (c >> 16) & 0xff) + - Sub3((a >> 8) & 0xff, (b >> 8) & 0xff, (c >> 8) & 0xff) + - Sub3((a ) & 0xff, (b ) & 0xff, (c ) & 0xff); - - return (pa_minus_pb <= 0) ? a : b; -} - -//------------------------------------------------------------------------------ -// Predictors - -static uint32_t Predictor0(uint32_t left, const uint32_t* const top) { - (void)top; - (void)left; - return ARGB_BLACK; -} -static uint32_t Predictor1(uint32_t left, const uint32_t* const top) { - (void)top; - return left; -} -static uint32_t Predictor2(uint32_t left, const uint32_t* const top) { - (void)left; - return top[0]; -} -static uint32_t Predictor3(uint32_t left, const uint32_t* const top) { - (void)left; - return top[1]; -} -static uint32_t Predictor4(uint32_t left, const uint32_t* const top) { - (void)left; - return top[-1]; -} -static uint32_t Predictor5(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Average3(left, top[0], top[1]); - return pred; -} -static uint32_t Predictor6(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Average2(left, top[-1]); - return pred; -} -static uint32_t Predictor7(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Average2(left, top[0]); - return pred; -} -static uint32_t Predictor8(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Average2(top[-1], top[0]); - (void)left; - return pred; -} -static uint32_t Predictor9(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Average2(top[0], top[1]); - (void)left; - return pred; -} -static uint32_t Predictor10(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Average4(left, top[-1], top[0], top[1]); - return pred; -} -static uint32_t Predictor11(uint32_t left, const uint32_t* const top) { - const uint32_t pred = Select(top[0], left, top[-1]); - return pred; -} -static uint32_t Predictor12(uint32_t left, const uint32_t* const top) { - const uint32_t pred = ClampedAddSubtractFull(left, top[0], top[-1]); - return pred; -} -static uint32_t Predictor13(uint32_t left, const uint32_t* const top) { - const uint32_t pred = ClampedAddSubtractHalf(left, top[0], top[-1]); - return pred; -} - -typedef uint32_t (*PredictorFunc)(uint32_t left, const uint32_t* const top); -static const PredictorFunc kPredictors[16] = { - Predictor0, Predictor1, Predictor2, Predictor3, - Predictor4, Predictor5, Predictor6, Predictor7, - Predictor8, Predictor9, Predictor10, Predictor11, - Predictor12, Predictor13, - Predictor0, Predictor0 // <- padding security sentinels -}; - -// TODO(vikasa): Replace 256 etc with defines. -static float PredictionCostSpatial(const int* counts, - int weight_0, double exp_val) { - const int significant_symbols = 16; - const double exp_decay_factor = 0.6; - double bits = weight_0 * counts[0]; - int i; - for (i = 1; i < significant_symbols; ++i) { - bits += exp_val * (counts[i] + counts[256 - i]); - exp_val *= exp_decay_factor; - } - return (float)(-0.1 * bits); -} - -// Compute the Shanon's entropy: Sum(p*log2(p)) -static float ShannonEntropy(const int* const array, int n) { - int i; - float retval = 0.f; - int sum = 0; - for (i = 0; i < n; ++i) { - if (array[i] != 0) { - sum += array[i]; - retval -= VP8LFastSLog2(array[i]); - } - } - retval += VP8LFastSLog2(sum); - return retval; -} - -static float PredictionCostSpatialHistogram(int accumulated[4][256], - int tile[4][256]) { - int i; - int k; - int combo[256]; - double retval = 0; - for (i = 0; i < 4; ++i) { - const double exp_val = 0.94; - retval += PredictionCostSpatial(&tile[i][0], 1, exp_val); - retval += ShannonEntropy(&tile[i][0], 256); - for (k = 0; k < 256; ++k) { - combo[k] = accumulated[i][k] + tile[i][k]; - } - retval += ShannonEntropy(&combo[0], 256); - } - return (float)retval; -} - -static int GetBestPredictorForTile(int width, int height, - int tile_x, int tile_y, int bits, - int accumulated[4][256], - const uint32_t* const argb_scratch) { - const int kNumPredModes = 14; - const int col_start = tile_x << bits; - const int row_start = tile_y << bits; - const int tile_size = 1 << bits; - const int ymax = (tile_size <= height - row_start) ? - tile_size : height - row_start; - const int xmax = (tile_size <= width - col_start) ? - tile_size : width - col_start; - int histo[4][256]; - float best_diff = MAX_DIFF_COST; - int best_mode = 0; - - int mode; - for (mode = 0; mode < kNumPredModes; ++mode) { - const uint32_t* current_row = argb_scratch; - const PredictorFunc pred_func = kPredictors[mode]; - float cur_diff; - int y; - memset(&histo[0][0], 0, sizeof(histo)); - for (y = 0; y < ymax; ++y) { - int x; - const int row = row_start + y; - const uint32_t* const upper_row = current_row; - current_row = upper_row + width; - for (x = 0; x < xmax; ++x) { - const int col = col_start + x; - uint32_t predict; - uint32_t predict_diff; - if (row == 0) { - predict = (col == 0) ? ARGB_BLACK : current_row[col - 1]; // Left. - } else if (col == 0) { - predict = upper_row[col]; // Top. - } else { - predict = pred_func(current_row[col - 1], upper_row + col); - } - predict_diff = VP8LSubPixels(current_row[col], predict); - ++histo[0][predict_diff >> 24]; - ++histo[1][((predict_diff >> 16) & 0xff)]; - ++histo[2][((predict_diff >> 8) & 0xff)]; - ++histo[3][(predict_diff & 0xff)]; - } - } - cur_diff = PredictionCostSpatialHistogram(accumulated, histo); - if (cur_diff < best_diff) { - best_diff = cur_diff; - best_mode = mode; - } - } - - return best_mode; -} - -static void CopyTileWithPrediction(int width, int height, - int tile_x, int tile_y, int bits, int mode, - const uint32_t* const argb_scratch, - uint32_t* const argb) { - const int col_start = tile_x << bits; - const int row_start = tile_y << bits; - const int tile_size = 1 << bits; - const int ymax = (tile_size <= height - row_start) ? - tile_size : height - row_start; - const int xmax = (tile_size <= width - col_start) ? - tile_size : width - col_start; - const PredictorFunc pred_func = kPredictors[mode]; - const uint32_t* current_row = argb_scratch; - - int y; - for (y = 0; y < ymax; ++y) { - int x; - const int row = row_start + y; - const uint32_t* const upper_row = current_row; - current_row = upper_row + width; - for (x = 0; x < xmax; ++x) { - const int col = col_start + x; - const int pix = row * width + col; - uint32_t predict; - if (row == 0) { - predict = (col == 0) ? ARGB_BLACK : current_row[col - 1]; // Left. - } else if (col == 0) { - predict = upper_row[col]; // Top. - } else { - predict = pred_func(current_row[col - 1], upper_row + col); - } - argb[pix] = VP8LSubPixels(current_row[col], predict); - } - } -} - -void VP8LResidualImage(int width, int height, int bits, - uint32_t* const argb, uint32_t* const argb_scratch, - uint32_t* const image) { - const int max_tile_size = 1 << bits; - const int tiles_per_row = VP8LSubSampleSize(width, bits); - const int tiles_per_col = VP8LSubSampleSize(height, bits); - uint32_t* const upper_row = argb_scratch; - uint32_t* const current_tile_rows = argb_scratch + width; - int tile_y; - int histo[4][256]; - memset(histo, 0, sizeof(histo)); - for (tile_y = 0; tile_y < tiles_per_col; ++tile_y) { - const int tile_y_offset = tile_y * max_tile_size; - const int this_tile_height = - (tile_y < tiles_per_col - 1) ? max_tile_size : height - tile_y_offset; - int tile_x; - if (tile_y > 0) { - memcpy(upper_row, current_tile_rows + (max_tile_size - 1) * width, - width * sizeof(*upper_row)); - } - memcpy(current_tile_rows, &argb[tile_y_offset * width], - this_tile_height * width * sizeof(*current_tile_rows)); - for (tile_x = 0; tile_x < tiles_per_row; ++tile_x) { - int pred; - int y; - const int tile_x_offset = tile_x * max_tile_size; - int all_x_max = tile_x_offset + max_tile_size; - if (all_x_max > width) { - all_x_max = width; - } - pred = GetBestPredictorForTile(width, height, tile_x, tile_y, bits, histo, - argb_scratch); - image[tile_y * tiles_per_row + tile_x] = 0xff000000u | (pred << 8); - CopyTileWithPrediction(width, height, tile_x, tile_y, bits, pred, - argb_scratch, argb); - for (y = 0; y < max_tile_size; ++y) { - int ix; - int all_x; - int all_y = tile_y_offset + y; - if (all_y >= height) { - break; - } - ix = all_y * width + tile_x_offset; - for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) { - const uint32_t a = argb[ix]; - ++histo[0][a >> 24]; - ++histo[1][((a >> 16) & 0xff)]; - ++histo[2][((a >> 8) & 0xff)]; - ++histo[3][(a & 0xff)]; - } - } - } - } -} - -// Inverse prediction. -static void PredictorInverseTransform(const VP8LTransform* const transform, - int y_start, int y_end, uint32_t* data) { - const int width = transform->xsize_; - if (y_start == 0) { // First Row follows the L (mode=1) mode. - int x; - const uint32_t pred0 = Predictor0(data[-1], NULL); - AddPixelsEq(data, pred0); - for (x = 1; x < width; ++x) { - const uint32_t pred1 = Predictor1(data[x - 1], NULL); - AddPixelsEq(data + x, pred1); - } - data += width; - ++y_start; - } - - { - int y = y_start; - const int mask = (1 << transform->bits_) - 1; - const int tiles_per_row = VP8LSubSampleSize(width, transform->bits_); - const uint32_t* pred_mode_base = - transform->data_ + (y >> transform->bits_) * tiles_per_row; - - while (y < y_end) { - int x; - const uint32_t pred2 = Predictor2(data[-1], data - width); - const uint32_t* pred_mode_src = pred_mode_base; - PredictorFunc pred_func; - - // First pixel follows the T (mode=2) mode. - AddPixelsEq(data, pred2); - - // .. the rest: - pred_func = kPredictors[((*pred_mode_src++) >> 8) & 0xf]; - for (x = 1; x < width; ++x) { - uint32_t pred; - if ((x & mask) == 0) { // start of tile. Read predictor function. - pred_func = kPredictors[((*pred_mode_src++) >> 8) & 0xf]; - } - pred = pred_func(data[x - 1], data + x - width); - AddPixelsEq(data + x, pred); - } - data += width; - ++y; - if ((y & mask) == 0) { // Use the same mask, since tiles are squares. - pred_mode_base += tiles_per_row; - } - } - } -} - -void VP8LSubtractGreenFromBlueAndRed(uint32_t* argb_data, int num_pixs) { - int i; - for (i = 0; i < num_pixs; ++i) { - const uint32_t argb = argb_data[i]; - const uint32_t green = (argb >> 8) & 0xff; - const uint32_t new_r = (((argb >> 16) & 0xff) - green) & 0xff; - const uint32_t new_b = ((argb & 0xff) - green) & 0xff; - argb_data[i] = (argb & 0xff00ff00) | (new_r << 16) | new_b; - } -} - -// Add green to blue and red channels (i.e. perform the inverse transform of -// 'subtract green'). -static void AddGreenToBlueAndRed(const VP8LTransform* const transform, - int y_start, int y_end, uint32_t* data) { - const int width = transform->xsize_; - const uint32_t* const data_end = data + (y_end - y_start) * width; - while (data < data_end) { - const uint32_t argb = *data; - // "* 0001001u" is equivalent to "(green << 16) + green)" - const uint32_t green = ((argb >> 8) & 0xff); - uint32_t red_blue = (argb & 0x00ff00ffu); - red_blue += (green << 16) | green; - red_blue &= 0x00ff00ffu; - *data++ = (argb & 0xff00ff00u) | red_blue; - } -} - -typedef struct { - // Note: the members are uint8_t, so that any negative values are - // automatically converted to "mod 256" values. - uint8_t green_to_red_; - uint8_t green_to_blue_; - uint8_t red_to_blue_; -} Multipliers; - -static WEBP_INLINE void MultipliersClear(Multipliers* m) { - m->green_to_red_ = 0; - m->green_to_blue_ = 0; - m->red_to_blue_ = 0; -} - -static WEBP_INLINE uint32_t ColorTransformDelta(int8_t color_pred, - int8_t color) { - return (uint32_t)((int)(color_pred) * color) >> 5; -} - -static WEBP_INLINE void ColorCodeToMultipliers(uint32_t color_code, - Multipliers* const m) { - m->green_to_red_ = (color_code >> 0) & 0xff; - m->green_to_blue_ = (color_code >> 8) & 0xff; - m->red_to_blue_ = (color_code >> 16) & 0xff; -} - -static WEBP_INLINE uint32_t MultipliersToColorCode(Multipliers* const m) { - return 0xff000000u | - ((uint32_t)(m->red_to_blue_) << 16) | - ((uint32_t)(m->green_to_blue_) << 8) | - m->green_to_red_; -} - -static WEBP_INLINE uint32_t TransformColor(const Multipliers* const m, - uint32_t argb, int inverse) { - const uint32_t green = argb >> 8; - const uint32_t red = argb >> 16; - uint32_t new_red = red; - uint32_t new_blue = argb; - - if (inverse) { - new_red += ColorTransformDelta(m->green_to_red_, green); - new_red &= 0xff; - new_blue += ColorTransformDelta(m->green_to_blue_, green); - new_blue += ColorTransformDelta(m->red_to_blue_, new_red); - new_blue &= 0xff; - } else { - new_red -= ColorTransformDelta(m->green_to_red_, green); - new_red &= 0xff; - new_blue -= ColorTransformDelta(m->green_to_blue_, green); - new_blue -= ColorTransformDelta(m->red_to_blue_, red); - new_blue &= 0xff; - } - return (argb & 0xff00ff00u) | (new_red << 16) | (new_blue); -} - -static WEBP_INLINE int SkipRepeatedPixels(const uint32_t* const argb, - int ix, int xsize) { - const uint32_t v = argb[ix]; - if (ix >= xsize + 3) { - if (v == argb[ix - xsize] && - argb[ix - 1] == argb[ix - xsize - 1] && - argb[ix - 2] == argb[ix - xsize - 2] && - argb[ix - 3] == argb[ix - xsize - 3]) { - return 1; - } - return v == argb[ix - 3] && v == argb[ix - 2] && v == argb[ix - 1]; - } else if (ix >= 3) { - return v == argb[ix - 3] && v == argb[ix - 2] && v == argb[ix - 1]; - } - return 0; -} - -static float PredictionCostCrossColor(const int accumulated[256], - const int counts[256]) { - // Favor low entropy, locally and globally. - int i; - int combo[256]; - for (i = 0; i < 256; ++i) { - combo[i] = accumulated[i] + counts[i]; - } - return ShannonEntropy(combo, 256) + - ShannonEntropy(counts, 256) + - PredictionCostSpatial(counts, 3, 2.4); // Favor small absolute values. -} - -static Multipliers GetBestColorTransformForTile( - int tile_x, int tile_y, int bits, - Multipliers prevX, - Multipliers prevY, - int step, int xsize, int ysize, - int* accumulated_red_histo, - int* accumulated_blue_histo, - const uint32_t* const argb) { - float best_diff = MAX_DIFF_COST; - float cur_diff; - const int halfstep = step / 2; - const int max_tile_size = 1 << bits; - const int tile_y_offset = tile_y * max_tile_size; - const int tile_x_offset = tile_x * max_tile_size; - int green_to_red; - int green_to_blue; - int red_to_blue; - int all_x_max = tile_x_offset + max_tile_size; - int all_y_max = tile_y_offset + max_tile_size; - Multipliers best_tx; - MultipliersClear(&best_tx); - if (all_x_max > xsize) { - all_x_max = xsize; - } - if (all_y_max > ysize) { - all_y_max = ysize; - } - for (green_to_red = -64; green_to_red <= 64; green_to_red += halfstep) { - int histo[256] = { 0 }; - int all_y; - Multipliers tx; - MultipliersClear(&tx); - tx.green_to_red_ = green_to_red & 0xff; - - for (all_y = tile_y_offset; all_y < all_y_max; ++all_y) { - uint32_t predict; - int ix = all_y * xsize + tile_x_offset; - int all_x; - for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) { - if (SkipRepeatedPixels(argb, ix, xsize)) { - continue; - } - predict = TransformColor(&tx, argb[ix], 0); - ++histo[(predict >> 16) & 0xff]; // red. - } - } - cur_diff = PredictionCostCrossColor(&accumulated_red_histo[0], &histo[0]); - if (tx.green_to_red_ == prevX.green_to_red_) { - cur_diff -= 3; // favor keeping the areas locally similar - } - if (tx.green_to_red_ == prevY.green_to_red_) { - cur_diff -= 3; // favor keeping the areas locally similar - } - if (tx.green_to_red_ == 0) { - cur_diff -= 3; - } - if (cur_diff < best_diff) { - best_diff = cur_diff; - best_tx = tx; - } - } - best_diff = MAX_DIFF_COST; - green_to_red = best_tx.green_to_red_; - for (green_to_blue = -32; green_to_blue <= 32; green_to_blue += step) { - for (red_to_blue = -32; red_to_blue <= 32; red_to_blue += step) { - int all_y; - int histo[256] = { 0 }; - Multipliers tx; - tx.green_to_red_ = green_to_red; - tx.green_to_blue_ = green_to_blue; - tx.red_to_blue_ = red_to_blue; - for (all_y = tile_y_offset; all_y < all_y_max; ++all_y) { - uint32_t predict; - int all_x; - int ix = all_y * xsize + tile_x_offset; - for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) { - if (SkipRepeatedPixels(argb, ix, xsize)) { - continue; - } - predict = TransformColor(&tx, argb[ix], 0); - ++histo[predict & 0xff]; // blue. - } - } - cur_diff = - PredictionCostCrossColor(&accumulated_blue_histo[0], &histo[0]); - if (tx.green_to_blue_ == prevX.green_to_blue_) { - cur_diff -= 3; // favor keeping the areas locally similar - } - if (tx.green_to_blue_ == prevY.green_to_blue_) { - cur_diff -= 3; // favor keeping the areas locally similar - } - if (tx.red_to_blue_ == prevX.red_to_blue_) { - cur_diff -= 3; // favor keeping the areas locally similar - } - if (tx.red_to_blue_ == prevY.red_to_blue_) { - cur_diff -= 3; // favor keeping the areas locally similar - } - if (tx.green_to_blue_ == 0) { - cur_diff -= 3; - } - if (tx.red_to_blue_ == 0) { - cur_diff -= 3; - } - if (cur_diff < best_diff) { - best_diff = cur_diff; - best_tx = tx; - } - } - } - return best_tx; -} - -static void CopyTileWithColorTransform(int xsize, int ysize, - int tile_x, int tile_y, int bits, - Multipliers color_transform, - uint32_t* const argb) { - int y; - int xscan = 1 << bits; - int yscan = 1 << bits; - tile_x <<= bits; - tile_y <<= bits; - if (xscan > xsize - tile_x) { - xscan = xsize - tile_x; - } - if (yscan > ysize - tile_y) { - yscan = ysize - tile_y; - } - yscan += tile_y; - for (y = tile_y; y < yscan; ++y) { - int ix = y * xsize + tile_x; - const int end_ix = ix + xscan; - for (; ix < end_ix; ++ix) { - argb[ix] = TransformColor(&color_transform, argb[ix], 0); - } - } -} - -void VP8LColorSpaceTransform(int width, int height, int bits, int step, - uint32_t* const argb, uint32_t* image) { - const int max_tile_size = 1 << bits; - int tile_xsize = VP8LSubSampleSize(width, bits); - int tile_ysize = VP8LSubSampleSize(height, bits); - int accumulated_red_histo[256] = { 0 }; - int accumulated_blue_histo[256] = { 0 }; - int tile_y; - int tile_x; - Multipliers prevX; - Multipliers prevY; - MultipliersClear(&prevY); - MultipliersClear(&prevX); - for (tile_y = 0; tile_y < tile_ysize; ++tile_y) { - for (tile_x = 0; tile_x < tile_xsize; ++tile_x) { - Multipliers color_transform; - int all_x_max; - int y; - const int tile_y_offset = tile_y * max_tile_size; - const int tile_x_offset = tile_x * max_tile_size; - if (tile_y != 0) { - ColorCodeToMultipliers(image[tile_y * tile_xsize + tile_x - 1], &prevX); - ColorCodeToMultipliers(image[(tile_y - 1) * tile_xsize + tile_x], - &prevY); - } else if (tile_x != 0) { - ColorCodeToMultipliers(image[tile_y * tile_xsize + tile_x - 1], &prevX); - } - color_transform = - GetBestColorTransformForTile(tile_x, tile_y, bits, - prevX, prevY, - step, width, height, - &accumulated_red_histo[0], - &accumulated_blue_histo[0], - argb); - image[tile_y * tile_xsize + tile_x] = - MultipliersToColorCode(&color_transform); - CopyTileWithColorTransform(width, height, tile_x, tile_y, bits, - color_transform, argb); - - // Gather accumulated histogram data. - all_x_max = tile_x_offset + max_tile_size; - if (all_x_max > width) { - all_x_max = width; - } - for (y = 0; y < max_tile_size; ++y) { - int ix; - int all_x; - int all_y = tile_y_offset + y; - if (all_y >= height) { - break; - } - ix = all_y * width + tile_x_offset; - for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) { - if (ix >= 2 && - argb[ix] == argb[ix - 2] && - argb[ix] == argb[ix - 1]) { - continue; // repeated pixels are handled by backward references - } - if (ix >= width + 2 && - argb[ix - 2] == argb[ix - width - 2] && - argb[ix - 1] == argb[ix - width - 1] && - argb[ix] == argb[ix - width]) { - continue; // repeated pixels are handled by backward references - } - ++accumulated_red_histo[(argb[ix] >> 16) & 0xff]; - ++accumulated_blue_histo[argb[ix] & 0xff]; - } - } - } - } -} - -// Color space inverse transform. -static void ColorSpaceInverseTransform(const VP8LTransform* const transform, - int y_start, int y_end, uint32_t* data) { - const int width = transform->xsize_; - const int mask = (1 << transform->bits_) - 1; - const int tiles_per_row = VP8LSubSampleSize(width, transform->bits_); - int y = y_start; - const uint32_t* pred_row = - transform->data_ + (y >> transform->bits_) * tiles_per_row; - - while (y < y_end) { - const uint32_t* pred = pred_row; - Multipliers m = { 0, 0, 0 }; - int x; - - for (x = 0; x < width; ++x) { - if ((x & mask) == 0) ColorCodeToMultipliers(*pred++, &m); - data[x] = TransformColor(&m, data[x], 1); - } - data += width; - ++y; - if ((y & mask) == 0) pred_row += tiles_per_row;; - } -} - -// Separate out pixels packed together using pixel-bundling. -static void ColorIndexInverseTransform( - const VP8LTransform* const transform, - int y_start, int y_end, const uint32_t* src, uint32_t* dst) { - int y; - const int bits_per_pixel = 8 >> transform->bits_; - const int width = transform->xsize_; - const uint32_t* const color_map = transform->data_; - if (bits_per_pixel < 8) { - const int pixels_per_byte = 1 << transform->bits_; - const int count_mask = pixels_per_byte - 1; - const uint32_t bit_mask = (1 << bits_per_pixel) - 1; - for (y = y_start; y < y_end; ++y) { - uint32_t packed_pixels = 0; - int x; - for (x = 0; x < width; ++x) { - // We need to load fresh 'packed_pixels' once every 'pixels_per_byte' - // increments of x. Fortunately, pixels_per_byte is a power of 2, so - // can just use a mask for that, instead of decrementing a counter. - if ((x & count_mask) == 0) packed_pixels = ((*src++) >> 8) & 0xff; - *dst++ = color_map[packed_pixels & bit_mask]; - packed_pixels >>= bits_per_pixel; - } - } - } else { - for (y = y_start; y < y_end; ++y) { - int x; - for (x = 0; x < width; ++x) { - *dst++ = color_map[((*src++) >> 8) & 0xff]; - } - } - } -} - -void VP8LInverseTransform(const VP8LTransform* const transform, - int row_start, int row_end, - const uint32_t* const in, uint32_t* const out) { - assert(row_start < row_end); - assert(row_end <= transform->ysize_); - switch (transform->type_) { - case SUBTRACT_GREEN: - AddGreenToBlueAndRed(transform, row_start, row_end, out); - break; - case PREDICTOR_TRANSFORM: - PredictorInverseTransform(transform, row_start, row_end, out); - if (row_end != transform->ysize_) { - // The last predicted row in this iteration will be the top-pred row - // for the first row in next iteration. - const int width = transform->xsize_; - memcpy(out - width, out + (row_end - row_start - 1) * width, - width * sizeof(*out)); - } - break; - case CROSS_COLOR_TRANSFORM: - ColorSpaceInverseTransform(transform, row_start, row_end, out); - break; - case COLOR_INDEXING_TRANSFORM: - if (in == out && transform->bits_ > 0) { - // Move packed pixels to the end of unpacked region, so that unpacking - // can occur seamlessly. - // Also, note that this is the only transform that applies on - // the effective width of VP8LSubSampleSize(xsize_, bits_). All other - // transforms work on effective width of xsize_. - const int out_stride = (row_end - row_start) * transform->xsize_; - const int in_stride = (row_end - row_start) * - VP8LSubSampleSize(transform->xsize_, transform->bits_); - uint32_t* const src = out + out_stride - in_stride; - memmove(src, out, in_stride * sizeof(*src)); - ColorIndexInverseTransform(transform, row_start, row_end, src, out); - } else { - ColorIndexInverseTransform(transform, row_start, row_end, in, out); - } - break; - } -} - -//------------------------------------------------------------------------------ -// Color space conversion. - -static int is_big_endian(void) { - static const union { - uint16_t w; - uint8_t b[2]; - } tmp = { 1 }; - return (tmp.b[0] != 1); -} - -static void ConvertBGRAToRGB(const uint32_t* src, - int num_pixels, uint8_t* dst) { - const uint32_t* const src_end = src + num_pixels; - while (src < src_end) { - const uint32_t argb = *src++; - *dst++ = (argb >> 16) & 0xff; - *dst++ = (argb >> 8) & 0xff; - *dst++ = (argb >> 0) & 0xff; - } -} - -static void ConvertBGRAToRGBA(const uint32_t* src, - int num_pixels, uint8_t* dst) { - const uint32_t* const src_end = src + num_pixels; - while (src < src_end) { - const uint32_t argb = *src++; - *dst++ = (argb >> 16) & 0xff; - *dst++ = (argb >> 8) & 0xff; - *dst++ = (argb >> 0) & 0xff; - *dst++ = (argb >> 24) & 0xff; - } -} - -static void ConvertBGRAToRGBA4444(const uint32_t* src, - int num_pixels, uint8_t* dst) { - const uint32_t* const src_end = src + num_pixels; - while (src < src_end) { - const uint32_t argb = *src++; - *dst++ = ((argb >> 16) & 0xf0) | ((argb >> 12) & 0xf); - *dst++ = ((argb >> 0) & 0xf0) | ((argb >> 28) & 0xf); - } -} - -static void ConvertBGRAToRGB565(const uint32_t* src, - int num_pixels, uint8_t* dst) { - const uint32_t* const src_end = src + num_pixels; - while (src < src_end) { - const uint32_t argb = *src++; - *dst++ = ((argb >> 16) & 0xf8) | ((argb >> 13) & 0x7); - *dst++ = ((argb >> 5) & 0xe0) | ((argb >> 3) & 0x1f); - } -} - -static void ConvertBGRAToBGR(const uint32_t* src, - int num_pixels, uint8_t* dst) { - const uint32_t* const src_end = src + num_pixels; - while (src < src_end) { - const uint32_t argb = *src++; - *dst++ = (argb >> 0) & 0xff; - *dst++ = (argb >> 8) & 0xff; - *dst++ = (argb >> 16) & 0xff; - } -} - -static void CopyOrSwap(const uint32_t* src, int num_pixels, uint8_t* dst, - int swap_on_big_endian) { - if (is_big_endian() == swap_on_big_endian) { - const uint32_t* const src_end = src + num_pixels; - while (src < src_end) { - uint32_t argb = *src++; -#if !defined(__BIG_ENDIAN__) && (defined(__i386__) || defined(__x86_64__)) - __asm__ volatile("bswap %0" : "=r"(argb) : "0"(argb)); - *(uint32_t*)dst = argb; - dst += sizeof(argb); -#elif !defined(__BIG_ENDIAN__) && defined(_MSC_VER) - argb = _byteswap_ulong(argb); - *(uint32_t*)dst = argb; - dst += sizeof(argb); -#else - *dst++ = (argb >> 24) & 0xff; - *dst++ = (argb >> 16) & 0xff; - *dst++ = (argb >> 8) & 0xff; - *dst++ = (argb >> 0) & 0xff; -#endif - } - } else { - memcpy(dst, src, num_pixels * sizeof(*src)); - } -} - -void VP8LConvertFromBGRA(const uint32_t* const in_data, int num_pixels, - WEBP_CSP_MODE out_colorspace, uint8_t* const rgba) { - switch (out_colorspace) { - case MODE_RGB: - ConvertBGRAToRGB(in_data, num_pixels, rgba); - break; - case MODE_RGBA: - ConvertBGRAToRGBA(in_data, num_pixels, rgba); - break; - case MODE_rgbA: - ConvertBGRAToRGBA(in_data, num_pixels, rgba); - WebPApplyAlphaMultiply(rgba, 0, num_pixels, 1, 0); - break; - case MODE_BGR: - ConvertBGRAToBGR(in_data, num_pixels, rgba); - break; - case MODE_BGRA: - CopyOrSwap(in_data, num_pixels, rgba, 1); - break; - case MODE_bgrA: - CopyOrSwap(in_data, num_pixels, rgba, 1); - WebPApplyAlphaMultiply(rgba, 0, num_pixels, 1, 0); - break; - case MODE_ARGB: - CopyOrSwap(in_data, num_pixels, rgba, 0); - break; - case MODE_Argb: - CopyOrSwap(in_data, num_pixels, rgba, 0); - WebPApplyAlphaMultiply(rgba, 1, num_pixels, 1, 0); - break; - case MODE_RGBA_4444: - ConvertBGRAToRGBA4444(in_data, num_pixels, rgba); - break; - case MODE_rgbA_4444: - ConvertBGRAToRGBA4444(in_data, num_pixels, rgba); - WebPApplyAlphaMultiply4444(rgba, num_pixels, 1, 0); - break; - case MODE_RGB_565: - ConvertBGRAToRGB565(in_data, num_pixels, rgba); - break; - default: - assert(0); // Code flow should not reach here. - } -} - -//------------------------------------------------------------------------------ - -#if defined(__cplusplus) || defined(c_plusplus) -} // extern "C" -#endif |