Message ID | 20210220185050.508373-2-derek.buitenhuis@gmail.com |
---|---|
State | Accepted |
Commit | 5f2804aba71dbf4833a3cc5e7b30e8351cd9037a |
Headers | show |
Series | GIF Palette Improvements | expand |
Context | Check | Description |
---|---|---|
andriy/x86_make | success | Make finished |
andriy/x86_make_fate | success | Make fate finished |
andriy/PPC64_make | success | Make finished |
andriy/PPC64_make_fate | success | Make fate finished |
On Sat, 20 Feb 2021, Derek Buitenhuis wrote: > This option will disable the writing of the global palette in global > GIF header if it is set to 0, causing only the frame-level palette > to ever be written. > > This will be useful later on when further frame-level palette > optimizations are introduced. > > The default is 1, which maintains current default behavior. > > Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com> > --- > Does this need a avcodec minor/patch version bump? > --- > libavcodec/gif.c | 21 +++++++++++++-------- > 1 file changed, 13 insertions(+), 8 deletions(-) docs update is missing for the new option. Regards, Marton > > diff --git a/libavcodec/gif.c b/libavcodec/gif.c > index de41992851..8c07ee2769 100644 > --- a/libavcodec/gif.c > +++ b/libavcodec/gif.c > @@ -51,6 +51,7 @@ typedef struct GIFContext { > AVFrame *last_frame; > int flags; > int image; > + int use_global_palette; > uint32_t palette[AVPALETTE_COUNT]; ///< local reference palette for !pal8 > int palette_loaded; > int transparent_index; > @@ -293,12 +294,14 @@ static int gif_image_write_image(AVCodecContext *avctx, > > bcid = get_palette_transparency_index(global_palette); > > - bytestream_put_byte(bytestream, 0xf7); /* flags: global clut, 256 entries */ > + bytestream_put_byte(bytestream, ((uint8_t) s->use_global_palette << 7) | 0x70 | (s->use_global_palette ? 7 : 0)); /* flags: global clut, 256 entries */ > bytestream_put_byte(bytestream, bcid < 0 ? DEFAULT_TRANSPARENCY_INDEX : bcid); /* background color index */ > bytestream_put_byte(bytestream, aspect); > - for (int i = 0; i < 256; i++) { > - const uint32_t v = global_palette[i] & 0xffffff; > - bytestream_put_be24(bytestream, v); > + if (s->use_global_palette) { > + for (int i = 0; i < 256; i++) { > + const uint32_t v = global_palette[i] & 0xffffff; > + bytestream_put_be24(bytestream, v); > + } > } > } > > @@ -330,15 +333,16 @@ static int gif_image_write_image(AVCodecContext *avctx, > bytestream_put_le16(bytestream, width); > bytestream_put_le16(bytestream, height); > > - if (!palette) { > - bytestream_put_byte(bytestream, 0x00); /* flags */ > - } else { > + if (palette || !s->use_global_palette) { > + const uint32_t *pal = palette ? palette : s->palette; > unsigned i; > bytestream_put_byte(bytestream, 1<<7 | 0x7); /* flags */ > for (i = 0; i < AVPALETTE_COUNT; i++) { > - const uint32_t v = palette[i]; > + const uint32_t v = pal[i]; > bytestream_put_be24(bytestream, v); > } > + } else { > + bytestream_put_byte(bytestream, 0x00); /* flags */ > } > > bytestream_put_byte(bytestream, 0x08); > @@ -473,6 +477,7 @@ static const AVOption gif_options[] = { > { "offsetting", "enable picture offsetting", 0, AV_OPT_TYPE_CONST, {.i64=GF_OFFSETTING}, INT_MIN, INT_MAX, FLAGS, "flags" }, > { "transdiff", "enable transparency detection between frames", 0, AV_OPT_TYPE_CONST, {.i64=GF_TRANSDIFF}, INT_MIN, INT_MAX, FLAGS, "flags" }, > { "gifimage", "enable encoding only images per frame", OFFSET(image), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS }, > + { "global_palette", "write a palette to the global gif header where feasible", OFFSET(use_global_palette), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS }, > { NULL } > }; > > -- > 2.30.0 > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
On 20/02/2021 19:58, Marton Balint wrote:
> docs update is missing for the new option.
Seems there was no documentation at all, so I've add all of it,
and sent patch 3/2.
- Derek
lgtm
diff --git a/libavcodec/gif.c b/libavcodec/gif.c index de41992851..8c07ee2769 100644 --- a/libavcodec/gif.c +++ b/libavcodec/gif.c @@ -51,6 +51,7 @@ typedef struct GIFContext { AVFrame *last_frame; int flags; int image; + int use_global_palette; uint32_t palette[AVPALETTE_COUNT]; ///< local reference palette for !pal8 int palette_loaded; int transparent_index; @@ -293,12 +294,14 @@ static int gif_image_write_image(AVCodecContext *avctx, bcid = get_palette_transparency_index(global_palette); - bytestream_put_byte(bytestream, 0xf7); /* flags: global clut, 256 entries */ + bytestream_put_byte(bytestream, ((uint8_t) s->use_global_palette << 7) | 0x70 | (s->use_global_palette ? 7 : 0)); /* flags: global clut, 256 entries */ bytestream_put_byte(bytestream, bcid < 0 ? DEFAULT_TRANSPARENCY_INDEX : bcid); /* background color index */ bytestream_put_byte(bytestream, aspect); - for (int i = 0; i < 256; i++) { - const uint32_t v = global_palette[i] & 0xffffff; - bytestream_put_be24(bytestream, v); + if (s->use_global_palette) { + for (int i = 0; i < 256; i++) { + const uint32_t v = global_palette[i] & 0xffffff; + bytestream_put_be24(bytestream, v); + } } } @@ -330,15 +333,16 @@ static int gif_image_write_image(AVCodecContext *avctx, bytestream_put_le16(bytestream, width); bytestream_put_le16(bytestream, height); - if (!palette) { - bytestream_put_byte(bytestream, 0x00); /* flags */ - } else { + if (palette || !s->use_global_palette) { + const uint32_t *pal = palette ? palette : s->palette; unsigned i; bytestream_put_byte(bytestream, 1<<7 | 0x7); /* flags */ for (i = 0; i < AVPALETTE_COUNT; i++) { - const uint32_t v = palette[i]; + const uint32_t v = pal[i]; bytestream_put_be24(bytestream, v); } + } else { + bytestream_put_byte(bytestream, 0x00); /* flags */ } bytestream_put_byte(bytestream, 0x08); @@ -473,6 +477,7 @@ static const AVOption gif_options[] = { { "offsetting", "enable picture offsetting", 0, AV_OPT_TYPE_CONST, {.i64=GF_OFFSETTING}, INT_MIN, INT_MAX, FLAGS, "flags" }, { "transdiff", "enable transparency detection between frames", 0, AV_OPT_TYPE_CONST, {.i64=GF_TRANSDIFF}, INT_MIN, INT_MAX, FLAGS, "flags" }, { "gifimage", "enable encoding only images per frame", OFFSET(image), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS }, + { "global_palette", "write a palette to the global gif header where feasible", OFFSET(use_global_palette), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS }, { NULL } };
This option will disable the writing of the global palette in global GIF header if it is set to 0, causing only the frame-level palette to ever be written. This will be useful later on when further frame-level palette optimizations are introduced. The default is 1, which maintains current default behavior. Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com> --- Does this need a avcodec minor/patch version bump? --- libavcodec/gif.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-)