diff options
| author | Øyvind Kolås <pippin@gimp.org> | 2014-03-23 02:13:26 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2014-03-25 13:48:06 +0100 |
| commit | 3e6016622e6fc5967e55d41e8074558d43bc33c0 (patch) | |
| tree | 8a6508c39c49af4f465967c3a273a597b5183ac4 /libswscale/options.c | |
| parent | a490970af2f081d3c0ae279b561406cb583ac9e4 (diff) | |
swscale: add two spatially stable dithering methods
Both of these dithering methods are from http://pippin.gimp.org/a_dither/ for
GIF they can be considered better than bayer (provides more gray-levels), and
spatial stability - often more than twice as good compression and less visual
flicker than error diffusion methods (the methods also avoids error-shadow
artifacts of diffusion dithers).
These methods are similar to blue/green noise type dither masks; but are
simple enough to generate their mask on the fly. They are still research work
in progress; though more expensive to generate masks (which can be used in a
LUT) like 'void and cluster' and similar methods will yield superior results
Diffstat (limited to 'libswscale/options.c')
| -rw-r--r-- | libswscale/options.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/libswscale/options.c b/libswscale/options.c index 9e8703ff39..5433d55b9b 100644 --- a/libswscale/options.c +++ b/libswscale/options.c @@ -69,10 +69,12 @@ static const AVOption swscale_options[] = { { "dst_v_chr_pos", "destination vertical chroma position in luma grid/256" , OFFSET(dst_v_chr_pos), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 512, VE }, { "dst_h_chr_pos", "destination horizontal chroma position in luma grid/256", OFFSET(dst_h_chr_pos), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 512, VE }, - { "sws_dither", "set dithering algorithm", OFFSET(dither), AV_OPT_TYPE_INT, { .i64 = SWS_DITHER_AUTO }, 0, NB_SWS_DITHER, VE, "sws_dither" }, - { "auto", "leave choice to sws", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_AUTO }, INT_MIN, INT_MAX, VE, "sws_dither" }, - { "bayer", "bayer dither", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_BAYER }, INT_MIN, INT_MAX, VE, "sws_dither" }, - { "ed", "error diffusion", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_ED }, INT_MIN, INT_MAX, VE, "sws_dither" }, + { "sws_dither", "set dithering algorithm", OFFSET(dither), AV_OPT_TYPE_INT, { .i64 = SWS_DITHER_AUTO }, 0, NB_SWS_DITHER, VE, "sws_dither" }, + { "auto", "leave choice to sws", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_AUTO }, INT_MIN, INT_MAX, VE, "sws_dither" }, + { "bayer", "bayer dither", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_BAYER }, INT_MIN, INT_MAX, VE, "sws_dither" }, + { "ed", "error diffusion", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_ED }, INT_MIN, INT_MAX, VE, "sws_dither" }, + { "a_dither", "arithmetic addition dither", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_A_DITHER}, INT_MIN, INT_MAX, VE, "sws_dither" }, + { "x_dither", "arithmetic xor dither", 0, AV_OPT_TYPE_CONST, { .i64 = SWS_DITHER_X_DITHER}, INT_MIN, INT_MAX, VE, "sws_dither" }, { NULL } }; |