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| author | Aman Gupta <aman@tmm1.net> | 2017-03-15 12:53:03 -0700 |
|---|---|---|
| committer | Aman Gupta <aman@tmm1.net> | 2017-11-15 18:14:39 -0800 |
| commit | 3f1a540204a8c187f77b3805d2e1c97fa916a12b (patch) | |
| tree | ee053abea06c4989caab1185a045427bc95897d8 /libavcodec/mpeg12dec.c | |
| parent | f399172d6e842fbdd05c599cdbbb1668c8c354be (diff) | |
| download | ffmpeg-3f1a540204a8c187f77b3805d2e1c97fa916a12b.tar.gz | |
avcodec/mpeg12dec: parse A53 caption data embedded in SCTE-20 user data
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Diffstat (limited to 'libavcodec/mpeg12dec.c')
| -rw-r--r-- | libavcodec/mpeg12dec.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c index 82bb1286ff..e2a7c3f2e0 100644 --- a/libavcodec/mpeg12dec.c +++ b/libavcodec/mpeg12dec.c @@ -2240,6 +2240,45 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx, avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS; } return 1; + } else if (buf_size >= 2 && + p[0] == 0x03 && (p[1]&0x7f) == 0x01) { + /* extract SCTE-20 CC data */ + GetBitContext gb; + int cc_count = 0; + int i; + + init_get_bits(&gb, p + 2, buf_size - 2); + cc_count = get_bits(&gb, 5); + if (cc_count > 0) { + av_freep(&s1->a53_caption); + s1->a53_caption_size = cc_count * 3; + s1->a53_caption = av_mallocz(s1->a53_caption_size); + if (s1->a53_caption) { + uint8_t field, cc1, cc2; + uint8_t *cap = s1->a53_caption; + for (i = 0; i < cc_count && get_bits_left(&gb) >= 26; i++) { + skip_bits(&gb, 2); // priority + field = get_bits(&gb, 2); + skip_bits(&gb, 5); // line_offset + cc1 = get_bits(&gb, 8); + cc2 = get_bits(&gb, 8); + skip_bits(&gb, 1); // marker + + if (!field) { // forbidden + cap[0] = cap[1] = cap[2] = 0x00; + } else { + field = (field == 2 ? 1 : 0); + if (!s1->mpeg_enc_ctx.top_field_first) field = !field; + cap[0] = 0x04 | field; + cap[1] = ff_reverse[cc1]; + cap[2] = ff_reverse[cc2]; + } + cap += 3; + } + } + avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS; + } + return 1; } else if (buf_size >= 11 && p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) { /* extract DVD CC data |