[FFmpeg-devel] [PATCH] avcodec/cdgraphics: fix transparency handling
Paul B Mahol
onemda at gmail.com
Thu Dec 16 12:33:16 EET 2021
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavcodec/cdgraphics.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/libavcodec/cdgraphics.c b/libavcodec/cdgraphics.c
index c9e265fa53..06f8392094 100644
--- a/libavcodec/cdgraphics.c
+++ b/libavcodec/cdgraphics.c
@@ -68,7 +68,7 @@ typedef struct CDGraphicsContext {
AVFrame *frame;
int hscroll;
int vscroll;
- int transparency;
+ uint8_t alpha[CDG_PALETTE_SIZE];
int cleared;
} CDGraphicsContext;
@@ -79,7 +79,9 @@ static av_cold int cdg_decode_init(AVCodecContext *avctx)
cc->frame = av_frame_alloc();
if (!cc->frame)
return AVERROR(ENOMEM);
- cc->transparency = -1;
+
+ for (int i = 0; i < CDG_PALETTE_SIZE; i++)
+ cc->alpha[i] = 0xFFU;
avctx->pix_fmt = AV_PIX_FMT_PAL8;
return ff_set_dimensions(avctx, CDG_FULL_WIDTH, CDG_FULL_HEIGHT);
@@ -120,9 +122,7 @@ static void cdg_load_palette(CDGraphicsContext *cc, uint8_t *data, int low)
r = ((color >> 8) & 0x000F) * 17;
g = ((color >> 4) & 0x000F) * 17;
b = ((color ) & 0x000F) * 17;
- palette[i + array_offset] = 0xFFU << 24 | r << 16 | g << 8 | b;
- if (cc->transparency >= 0)
- palette[cc->transparency] &= 0xFFFFFF;
+ palette[i + array_offset] = cc->alpha[i + array_offset] << 24 | r << 16 | g << 8 | b;
}
cc->frame->palette_has_changed = 1;
}
@@ -346,7 +346,8 @@ static int cdg_decode_frame(AVCodecContext *avctx,
return ret;
break;
case CDG_INST_TRANSPARENT_COL:
- cc->transparency = cdg_data[0] & 0xF;
+ for (int i = 0; i < CDG_PALETTE_SIZE; i++)
+ cc->alpha[i] = 255 - ((cdg_data[i] & 0x3f) << 2);
break;
default:
break;
--
2.33.0
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