diff options
| author | Paul B Mahol <onemda@gmail.com> | 2020-06-20 15:02:48 +0200 |
|---|---|---|
| committer | Paul B Mahol <onemda@gmail.com> | 2020-06-20 15:09:30 +0200 |
| commit | 29ea4e1b3c511de0a406722bcfffa11604745451 (patch) | |
| tree | 1def1d280cedf5a7475354054b403fa0a1c5fbb7 | |
| parent | 00842b3a0dee8cd1729c0c7566e0ca4272271bc3 (diff) | |
avcodec/mpeg12dec: do not discard older a53 captions
Fixes #6105.
| -rw-r--r-- | libavcodec/mpeg12dec.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c index a12857d358..1253bde66e 100644 --- a/libavcodec/mpeg12dec.c +++ b/libavcodec/mpeg12dec.c @@ -2242,13 +2242,25 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx, /* extract A53 Part 4 CC data */ int cc_count = p[5] & 0x1f; if (cc_count > 0 && buf_size >= 7 + cc_count * 3) { - av_freep(&s1->a53_caption); - s1->a53_caption_size = cc_count * 3; - s1->a53_caption = av_malloc(s1->a53_caption_size); + if (s1->a53_caption && s1->a53_caption_size > 0) { + uint8_t *old_a53_caption = s1->a53_caption; + int old_a53_caption_size = s1->a53_caption_size; + + s1->a53_caption_size = old_a53_caption_size + cc_count * 3; + s1->a53_caption = av_malloc(s1->a53_caption_size); + if (s1->a53_caption) { + memcpy(s1->a53_caption, old_a53_caption, old_a53_caption_size); + memcpy(s1->a53_caption + old_a53_caption_size, p + 7, cc_count * 3); + } + av_freep(&old_a53_caption); + } else { + s1->a53_caption_size = cc_count * 3; + s1->a53_caption = av_malloc(s1->a53_caption_size); + if (s1->a53_caption) + memcpy(s1->a53_caption, p + 7, s1->a53_caption_size); + } if (!s1->a53_caption) { s1->a53_caption_size = 0; - } else { - memcpy(s1->a53_caption, p + 7, s1->a53_caption_size); } avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS; } |