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Merge "Increase the transform bits if possible." into main
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
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@@ -14,6 +14,8 @@ | |
| // Urvang Joshi ([email protected]) | ||
| // Vincent Rabaud ([email protected]) | ||
|
|
||
| #include <string.h> | ||
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||
| #include "src/dsp/lossless.h" | ||
| #include "src/dsp/lossless_common.h" | ||
| #include "src/enc/vp8i_enc.h" | ||
|
|
@@ -469,6 +471,71 @@ static void CopyImageWithPrediction(int width, int height, int bits, | |
| } | ||
| } | ||
|
|
||
| // Checks whether 'image' can be subsampled by finding the biggest power of 2 | ||
| // squares (defined by 'best_bits') of uniform value it is made out of. | ||
| static void OptimizeSampling(uint32_t* const image, int full_width, | ||
| int full_height, int bits, int* best_bits_out) { | ||
| int width = VP8LSubSampleSize(full_width, bits); | ||
| int height = VP8LSubSampleSize(full_height, bits); | ||
| int old_width, x, y, square_size; | ||
| int best_bits = bits; | ||
| *best_bits_out = bits; | ||
| // Check rows first. | ||
| while (best_bits < MAX_TRANSFORM_BITS) { | ||
| const int new_square_size = 1 << (best_bits + 1 - bits); | ||
| int is_good = 1; | ||
| square_size = 1 << (best_bits - bits); | ||
| for (y = 0; y + square_size < height; y += new_square_size) { | ||
| // Check the first lines of consecutive line groups. | ||
| if (memcmp(&image[y * width], &image[(y + square_size) * width], | ||
| width * sizeof(*image)) != 0) { | ||
| is_good = 0; | ||
| break; | ||
| } | ||
| } | ||
| if (is_good) { | ||
| ++best_bits; | ||
| } else { | ||
| break; | ||
| } | ||
| } | ||
| if (best_bits == bits) return; | ||
|
|
||
| // Check columns. | ||
| while (best_bits > bits) { | ||
| int is_good = 1; | ||
| square_size = 1 << (best_bits - bits); | ||
| for (y = 0; is_good && y < height; ++y) { | ||
| for (x = 0; is_good && x < width; x += square_size) { | ||
| int i; | ||
| for (i = x + 1; i < GetMin(x + square_size, width); ++i) { | ||
| if (image[y * width + i] != image[y * width + x]) { | ||
| is_good = 0; | ||
| break; | ||
| } | ||
| } | ||
| } | ||
| } | ||
| if (is_good) { | ||
| break; | ||
| } | ||
| --best_bits; | ||
| } | ||
| if (best_bits == bits) return; | ||
|
|
||
| // Subsample the image. | ||
| old_width = width; | ||
| square_size = 1 << (best_bits - bits); | ||
| width = VP8LSubSampleSize(full_width, best_bits); | ||
| height = VP8LSubSampleSize(full_height, best_bits); | ||
| for (y = 0; y < height; ++y) { | ||
| for (x = 0; x < width; ++x) { | ||
| image[y * width + x] = image[square_size * (y * old_width + x)]; | ||
| } | ||
| } | ||
| *best_bits_out = best_bits; | ||
| } | ||
|
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||
| // Finds the best predictor for each tile, and converts the image to residuals | ||
| // with respect to predictions. If near_lossless_quality < 100, applies | ||
| // near lossless processing, shaving off more bits of residuals for lower | ||
|
|
@@ -478,7 +545,7 @@ int VP8LResidualImage(int width, int height, int bits, int low_effort, | |
| uint32_t* const image, int near_lossless_quality, | ||
| int exact, int used_subtract_green, | ||
| const WebPPicture* const pic, int percent_range, | ||
| int* const percent) { | ||
| int* const percent, int* const best_bits) { | ||
| const int tiles_per_row = VP8LSubSampleSize(width, bits); | ||
| const int tiles_per_col = VP8LSubSampleSize(height, bits); | ||
| int percent_start = *percent; | ||
|
|
@@ -488,6 +555,7 @@ int VP8LResidualImage(int width, int height, int bits, int low_effort, | |
| for (i = 0; i < tiles_per_row * tiles_per_col; ++i) { | ||
| image[i] = ARGB_BLACK | (kPredLowEffort << 8); | ||
| } | ||
| *best_bits = bits; | ||
| } else { | ||
| int tile_y; | ||
| uint32_t histo[HISTO_SIZE] = { 0 }; | ||
|
|
@@ -506,9 +574,10 @@ int VP8LResidualImage(int width, int height, int bits, int low_effort, | |
| return 0; | ||
| } | ||
| } | ||
| OptimizeSampling(image, width, height, bits, best_bits); | ||
| } | ||
|
|
||
| CopyImageWithPrediction(width, height, bits, image, argb_scratch, argb, | ||
| CopyImageWithPrediction(width, height, *best_bits, image, argb_scratch, argb, | ||
| low_effort, max_quantization, exact, | ||
| used_subtract_green); | ||
| return WebPReportProgress(pic, percent_start + percent_range, percent); | ||
|
|
@@ -727,7 +796,7 @@ static void CopyTileWithColorTransform(int xsize, int ysize, | |
| int VP8LColorSpaceTransform(int width, int height, int bits, int quality, | ||
| uint32_t* const argb, uint32_t* image, | ||
| const WebPPicture* const pic, int percent_range, | ||
| int* const percent) { | ||
| int* const percent, int* const best_bits) { | ||
| const int max_tile_size = 1 << bits; | ||
| const int tile_xsize = VP8LSubSampleSize(width, bits); | ||
| const int tile_ysize = VP8LSubSampleSize(height, bits); | ||
|
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@@ -787,5 +856,6 @@ int VP8LColorSpaceTransform(int width, int height, int bits, int quality, | |
| return 0; | ||
| } | ||
| } | ||
| OptimizeSampling(image, width, height, bits, best_bits); | ||
| return 1; | ||
| } | ||
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