[FFmpeg-devel] [PATCH 1/2] vp8: WebP decoding support

[Michael Niedermayer]

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
---
 libavcodec/vp8.c |   19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/libavcodec/vp8.c b/libavcodec/vp8.c
index ac929d0..1dbe959 100644
--- a/libavcodec/vp8.c
+++ b/libavcodec/vp8.c
@@ -304,6 +304,25 @@ static int decode_frame_header(VP8Context *s, const uint8_t *buf, int buf_size)
     int width  = s->avctx->width;
     int height = s->avctx->height;
 
+    if (   AV_RL32(buf   ) == AV_RL32("RIFF")
+        && AV_RL32(buf+ 8) == AV_RL32("WEBP")) {
+        if (AV_RL32(buf+12) == AV_RL32("VP8X") && AV_RL32(buf+16) < (unsigned)buf_size) {
+            unsigned size = AV_RL32(buf+16) + 8;
+            buf      += size;
+            buf_size -= size;
+        }
+        if (AV_RL32(buf+12) == AV_RL32("ALPH") && AV_RL32(buf+16) < (unsigned)buf_size) {
+            unsigned size = AV_RL32(buf+16) + 8 + 1;
+            buf      += size;
+            buf_size -= size;
+            av_log(s->avctx, AV_LOG_WARNING, "Skiping alpha plane\n");
+        }
+        if (AV_RL32(buf+12) == AV_RL32("VP8 ")) {
+            buf      += 20;
+            buf_size -= 20;
+        }
+    }
+
     s->keyframe  = !(buf[0] & 1);
     s->profile   =  (buf[0]>>1) & 7;
     s->invisible = !(buf[0] & 0x10);
-- 
1.7.9.5