[FFmpeg-devel] [PATCH] avcodec/aac_ac3_parser: account for data already in the parsing buffer

Hendrik Leppkes h.leppkes at gmail.com
Wed Apr 11 14:40:40 EEST 2018

If a frame starts very close to a packet boundary, the start code may
already have been added to the parsing buffer, indicated by a small
negative value of "i", while the header is still being tracked in the
"state" variable.

Reduce the remaining size accordingly, otherwise trying to find the next
frame could skip over the frame header and lump two frames together as
 libavcodec/aac_ac3_parser.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/aac_ac3_parser.c b/libavcodec/aac_ac3_parser.c
index 019074b0dd..7f20626285 100644
--- a/libavcodec/aac_ac3_parser.c
+++ b/libavcodec/aac_ac3_parser.c
@@ -60,6 +60,8 @@ get_next:
                     s->remaining_size += i;
                     goto get_next;
+                else if (i < 0)
+                    s->remaining_size += i;

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