diff options
| -rw-r--r-- | libavcodec/dvdsubdec.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/libavcodec/dvdsubdec.c b/libavcodec/dvdsubdec.c index bb3e124bcd..6d5973c59b 100644 --- a/libavcodec/dvdsubdec.c +++ b/libavcodec/dvdsubdec.c @@ -120,6 +120,14 @@ static void guess_palette(uint32_t *rgba_palette, uint8_t *alpha, uint32_t subtitle_color) { + static const uint8_t level_map[4][4] = { + // this configuration (full range, lowest to highest) in tests + // seemed most common, so assume this + {0xff}, + {0x00, 0xff}, + {0x00, 0x80, 0xff}, + {0x00, 0x55, 0xaa, 0xff}, + }; uint8_t color_used[16]; int nb_opaque_colors, i, level, j, r, g, b; @@ -138,18 +146,18 @@ static void guess_palette(uint32_t *rgba_palette, if (nb_opaque_colors == 0) return; - j = nb_opaque_colors; + j = 0; memset(color_used, 0, 16); for(i = 0; i < 4; i++) { if (alpha[i] != 0) { if (!color_used[colormap[i]]) { - level = (0xff * j) / nb_opaque_colors; + level = level_map[nb_opaque_colors][j]; r = (((subtitle_color >> 16) & 0xff) * level) >> 8; g = (((subtitle_color >> 8) & 0xff) * level) >> 8; b = (((subtitle_color >> 0) & 0xff) * level) >> 8; rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17) << 24); color_used[colormap[i]] = (i + 1); - j--; + j++; } else { rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) | ((alpha[i] * 17) << 24); |