| // 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) |
| |
| #define ANDROID_WEBP_RGB |
| |
| #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++; |
| #ifdef ANDROID_WEBP_RGB |
| *dst++ = ((argb >> 0) & 0xf0) | ((argb >> 28) & 0xf); |
| *dst++ = ((argb >> 16) & 0xf0) | ((argb >> 12) & 0xf); |
| #else |
| *dst++ = ((argb >> 16) & 0xf0) | ((argb >> 12) & 0xf); |
| *dst++ = ((argb >> 0) & 0xf0) | ((argb >> 28) & 0xf); |
| #endif |
| } |
| } |
| |
| 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++; |
| #ifdef ANDROID_WEBP_RGB |
| *dst++ = ((argb >> 5) & 0xe0) | ((argb >> 3) & 0x1f); |
| *dst++ = ((argb >> 16) & 0xf8) | ((argb >> 13) & 0x7); |
| #else |
| *dst++ = ((argb >> 16) & 0xf8) | ((argb >> 13) & 0x7); |
| *dst++ = ((argb >> 5) & 0xe0) | ((argb >> 3) & 0x1f); |
| #endif |
| } |
| } |
| |
| 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 |