diff --git a/src/enc/vp8l_enc.c b/src/enc/vp8l_enc.c index ae9fe5ff..58844201 100644 --- a/src/enc/vp8l_enc.c +++ b/src/enc/vp8l_enc.c @@ -196,7 +196,7 @@ static int AnalyzeEntropy(const uint32_t* argb, if (use_palette && palette_size <= 16) { // In the case of small palettes, we pack 2, 4 or 8 pixels together. In - // practice, small palette are better than any other transform. + // practice, small palettes are better than any other transform. *min_entropy_ix = kPalette; *red_and_blue_always_zero = 1; return 1; @@ -206,10 +206,12 @@ static int AnalyzeEntropy(const uint32_t* argb, int i, x, y; const uint32_t* prev_row = NULL; const uint32_t* curr_row = argb; + uint32_t pix_prev = argb[0]; // Skip the first pixel. for (y = 0; y < height; ++y) { - for (x = 1; x < width; ++x) { + for (x = 0; x < width; ++x) { const uint32_t pix = curr_row[x]; - const uint32_t pix_diff = VP8LSubPixels(pix, curr_row[x - 1]); + const uint32_t pix_diff = VP8LSubPixels(pix, pix_prev); + pix_prev = pix; if ((pix_diff == 0) || (prev_row != NULL && pix == prev_row[x])) { continue; } @@ -292,20 +294,10 @@ static int AnalyzeEntropy(const uint32_t* argb, // lower cost than sizeof(uint32_t)*8. entropy[kPalette] += palette_size * 8; - if (use_palette && entropy[kDirect] == 0) { - // If the entropy is null, there should only be one color, - // and that case is handled at the very beginning of that function. - // Unfortunately, we can also have a null entropy because we skip the - // first column (an image with constant values on each line generates - // a null entropy but could have a different color per line). - // TODO(vrabaud) investigate and fix. - *min_entropy_ix = kPalette; - } else { - *min_entropy_ix = kDirect; - for (k = kDirect + 1; k <= last_mode_to_analyze; ++k) { - if (entropy[*min_entropy_ix] > entropy[k]) { - *min_entropy_ix = (EntropyIx)k; - } + *min_entropy_ix = kDirect; + for (k = kDirect + 1; k <= last_mode_to_analyze; ++k) { + if (entropy[*min_entropy_ix] > entropy[k]) { + *min_entropy_ix = (EntropyIx)k; } } assert((int)*min_entropy_ix <= last_mode_to_analyze);