diff options
| author | Clément Bœsch <u@pkh.me> | 2022-12-30 11:38:01 +0100 |
|---|---|---|
| committer | Clément Bœsch <u@pkh.me> | 2023-01-03 17:29:13 +0100 |
| commit | c973e8ae79ae59e7f2d54b6f4c10c2fd91e461da (patch) | |
| tree | 38aee80d264a2b0bdd73ec1129f0c0dd87804194 /libavfilter/vf_paletteuse.c | |
| parent | 9973343bf936a334b850a2b60724baa46f3cc250 (diff) | |
avfilter/paletteuse: add burkes dithering
Burkes according to
https://bisqwit.iki.fi/jutut/kuvat/ordered_dither/error_diffusion.txt:
* 8 4
2 4 8 4 2 / 32
Diffstat (limited to 'libavfilter/vf_paletteuse.c')
| -rw-r--r-- | libavfilter/vf_paletteuse.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/libavfilter/vf_paletteuse.c b/libavfilter/vf_paletteuse.c index 902bf5d82f..3c3b6b3ef8 100644 --- a/libavfilter/vf_paletteuse.c +++ b/libavfilter/vf_paletteuse.c @@ -43,6 +43,7 @@ enum dithering_mode { DITHERING_SIERRA2, DITHERING_SIERRA2_4A, DITHERING_SIERRA3, + DITHERING_BURKES, NB_DITHERING }; @@ -115,6 +116,7 @@ static const AVOption paletteuse_options[] = { { "sierra2", "Frankie Sierra dithering v2 (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_SIERRA2}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" }, { "sierra2_4a", "Frankie Sierra dithering v2 \"Lite\" (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_SIERRA2_4A}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" }, { "sierra3", "Frankie Sierra dithering v3 (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_SIERRA3}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" }, + { "burkes", "Burkes dithering (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_BURKES}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" }, { "bayer_scale", "set scale for bayer dithering", OFFSET(bayer_scale), AV_OPT_TYPE_INT, {.i64=2}, 0, 5, FLAGS }, { "diff_mode", "set frame difference mode", OFFSET(diff_mode), AV_OPT_TYPE_INT, {.i64=DIFF_MODE_NONE}, 0, NB_DIFF_MODE-1, FLAGS, "diff_mode" }, { "rectangle", "process smallest different rectangle", 0, AV_OPT_TYPE_CONST, {.i64=DIFF_MODE_RECTANGLE}, INT_MIN, INT_MAX, FLAGS, "diff_mode" }, @@ -396,6 +398,26 @@ static av_always_inline int set_frame(PaletteUseContext *s, AVFrame *out, AVFram } } + } else if (dither == DITHERING_BURKES) { + const int right = x < w - 1, down = y < h - 1, left = x > x_start; + const int right2 = x < w - 2, left2 = x > x_start + 1; + const int color = get_dst_color_err(s, src[x], &er, &eg, &eb); + + if (color < 0) + return color; + dst[x] = color; + + if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 8, 5); + if (right2) src[ x + 2] = dither_color(src[ x + 2], er, eg, eb, 4, 5); + + if (down) { + if (left2) src[src_linesize + x - 2] = dither_color(src[src_linesize + x - 2], er, eg, eb, 2, 5); + if (left) src[src_linesize + x - 1] = dither_color(src[src_linesize + x - 1], er, eg, eb, 4, 5); + if (1) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 8, 5); + if (right) src[src_linesize + x + 1] = dither_color(src[src_linesize + x + 1], er, eg, eb, 4, 5); + if (right2) src[src_linesize + x + 2] = dither_color(src[src_linesize + x + 2], er, eg, eb, 2, 5); + } + } else { const int color = color_get(s, src[x]); @@ -871,6 +893,7 @@ DEFINE_SET_FRAME(floyd_steinberg, DITHERING_FLOYD_STEINBERG) DEFINE_SET_FRAME(sierra2, DITHERING_SIERRA2) DEFINE_SET_FRAME(sierra2_4a, DITHERING_SIERRA2_4A) DEFINE_SET_FRAME(sierra3, DITHERING_SIERRA3) +DEFINE_SET_FRAME(burkes, DITHERING_BURKES) static const set_frame_func set_frame_lut[NB_DITHERING] = { set_frame_none, @@ -880,6 +903,7 @@ static const set_frame_func set_frame_lut[NB_DITHERING] = { set_frame_sierra2, set_frame_sierra2_4a, set_frame_sierra3, + set_frame_burkes, }; static int dither_value(int p) |