iff: support ExtraHalfBrite (EHB) palette mode

Fixes ticket #663.

Based on patch by ami_stuff

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Peter Ross 2011-12-03 13:01:58 +11:00 committed by Michael Niedermayer
parent 56f6628bca
commit 52b7ed4f6e

View File

@ -137,6 +137,7 @@ static av_always_inline uint32_t gray2rgb(const uint32_t x) {
*/
static int ff_cmap_read_palette(AVCodecContext *avctx, uint32_t *pal)
{
IffContext *s = avctx->priv_data;
int count, i;
const uint8_t *const palette = avctx->extradata + AV_RB16(avctx->extradata);
int palette_size = avctx->extradata_size - AV_RB16(avctx->extradata);
@ -153,6 +154,10 @@ static int ff_cmap_read_palette(AVCodecContext *avctx, uint32_t *pal)
for (i=0; i < count; i++) {
pal[i] = 0xFF000000 | AV_RB24(palette + i*3);
}
if (s->flags && count >= 32) { // EHB
for (i = 0; i < 32; i++)
pal[i + 32] = 0xFF000000 | (AV_RB24(palette + i*3) & 0xFEFEFE) >> 1;
}
} else { // Create gray-scale color palette for bps < 8
count = 1 << avctx->bits_per_coded_sample;
@ -266,9 +271,6 @@ static int extract_header(AVCodecContext *const avctx,
s->ham_palbuf[(i+count*2)*2+1] = tmp;
s->ham_palbuf[(i+count*3)*2+1] = tmp << 8;
}
} else if (s->flags & 1) { // EHB (ExtraHalfBrite) color palette
av_log(avctx, AV_LOG_ERROR, "ExtraHalfBrite (EHB) mode not supported\n");
return AVERROR_PATCHWELCOME;
}
}