[FFmpeg-devel] [PATCH 2/2] avcodec: add an AVCodecContext flag to export A53/SCTE20/DVD CC side data on demand

[lance.lmwang@gmail.com]

From: Limin Wang <lance.lmwang@gmail.com>

some samples include both A53 and SCTE20 data. Before the commit, both
of the will be exported, so the CC data will be repeated or garbarge
as they're using the same frame side data. If you know your samples include
only one of them, You can export by +a53cc+scte20.

After the commit, the default will not export MPEG2 A53/SCTE20/DVD CC side data,
please export on demand.

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
---
 doc/codecs.texi            | 10 ++++++++++
 libavcodec/avcodec.h       | 16 +++++++++++++++-
 libavcodec/mpeg12dec.c     |  6 +++---
 libavcodec/options_table.h |  3 +++
 libavcodec/version.h       |  2 +-
 tests/fate/ffmpeg.mak      |  2 +-
 tests/fate/subtitles.mak   |  6 +++---
 7 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/doc/codecs.texi b/doc/codecs.texi
index 5e10020900..4cced983b9 100644
--- a/doc/codecs.texi
+++ b/doc/codecs.texi
@@ -662,6 +662,16 @@ for codecs that support it. At present, those are H.264 and VP9.
 @item film_grain
 Export film grain parameters through frame side data (see @code{AV_FRAME_DATA_FILM_GRAIN_PARAMS}).
 Supported at present by AV1 decoders.
+@item a53cc
+Export A53 CC through frame side data (see @code{AV_FRAME_DATA_A53_CC})
+for codecs that support it.
+@item scte20cc
+Export SCTE20 CC through frame side data (see @code{AV_FRAME_DATA_A53_CC})
+for codecs that support it.
+@item dvdcc
+Export DVD CC through frame side data (see @code{AV_FRAME_DATA_A53_CC})
+for codecs that support it.
+
 @end table
 
 @item threads @var{integer} (@emph{decoding/encoding,video})
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 4dae23d06e..25fd4de2fe 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -360,7 +360,21 @@ typedef struct RcOverride{
  * Do not apply film grain, export it instead.
  */
 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
-
+/**
+ * Decoding only.
+ * Export A53 CC through frame side data
+ */
+#define AV_CODEC_EXPORT_DATA_A53_CC (1 << 4)
+/**
+ * Decoding only.
+ * Export SCTE20 CC through frame side data
+ */
+#define AV_CODEC_EXPORT_DATA_SCTE20_CC (1 << 5)
+/**
+ * Decoding only.
+ * Export DVD CC through frame side data
+ */
+#define AV_CODEC_EXPORT_DATA_DVD_CC (1 << 6)
 /**
  * The decoder will keep a reference to the frame and may reuse it later.
  */
diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
index e9bde48f7a..032cb8f9b1 100644
--- a/libavcodec/mpeg12dec.c
+++ b/libavcodec/mpeg12dec.c
@@ -2203,7 +2203,7 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx,
 {
     Mpeg1Context *s1 = avctx->priv_data;
 
-    if (buf_size >= 6 &&
+    if (buf_size >= 6 && (avctx->export_side_data & AV_CODEC_EXPORT_DATA_A53_CC) &&
         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
         p[4] == 3 && (p[5] & 0x40)) {
         /* extract A53 Part 4 CC data */
@@ -2224,7 +2224,7 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx,
             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
         }
         return 1;
-    } else if (buf_size >= 2 &&
+    } else if (buf_size >= 2 && (avctx->export_side_data & AV_CODEC_EXPORT_DATA_SCTE20_CC) &&
                p[0] == 0x03 && (p[1]&0x7f) == 0x01) {
         /* extract SCTE-20 CC data */
         GetBitContext gb;
@@ -2269,7 +2269,7 @@ static int mpeg_decode_a53_cc(AVCodecContext *avctx,
             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
         }
         return 1;
-    } else if (buf_size >= 11 &&
+    } else if (buf_size >= 11 && (avctx->export_side_data & AV_CODEC_EXPORT_DATA_DVD_CC) &&
                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
         /* extract DVD CC data
          *
diff --git a/libavcodec/options_table.h b/libavcodec/options_table.h
index e72b4d12b6..3c6db07459 100644
--- a/libavcodec/options_table.h
+++ b/libavcodec/options_table.h
@@ -88,6 +88,9 @@ static const AVOption avcodec_options[] = {
 {"prft", "export Producer Reference Time through packet side data", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_EXPORT_DATA_PRFT}, INT_MIN, INT_MAX, A|V|S|E, "export_side_data"},
 {"venc_params", "export video encoding parameters through frame side data", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS}, INT_MIN, INT_MAX, V|D, "export_side_data"},
 {"film_grain", "export film grain parameters through frame side data", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_EXPORT_DATA_FILM_GRAIN}, INT_MIN, INT_MAX, V|D, "export_side_data"},
+{"a53cc", "export A53 CC through frame side data", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_EXPORT_DATA_A53_CC}, INT_MIN, INT_MAX, V|D, "export_side_data"},
+{"scte20cc", "export SCTE20 CC through frame side data", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_EXPORT_DATA_SCTE20_CC}, INT_MIN, INT_MAX, V|D, "export_side_data"},
+{"dvdcc", "export DVD CC through frame side data", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_EXPORT_DATA_DVD_CC}, INT_MIN, INT_MAX, V|D, "export_side_data"},
 {"time_base", NULL, OFFSET(time_base), AV_OPT_TYPE_RATIONAL, {.dbl = 0}, 0, INT_MAX},
 {"g", "set the group of picture (GOP) size", OFFSET(gop_size), AV_OPT_TYPE_INT, {.i64 = 12 }, INT_MIN, INT_MAX, V|E},
 {"ar", "set audio sampling rate (in Hz)", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = DEFAULT }, 0, INT_MAX, A|D|E},
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 735c8b813c..87b7284a95 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -29,7 +29,7 @@
 
 #include "version_major.h"
 
-#define LIBAVCODEC_VERSION_MINOR  27
+#define LIBAVCODEC_VERSION_MINOR  28
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
diff --git a/tests/fate/ffmpeg.mak b/tests/fate/ffmpeg.mak
index 9d14a96e13..a403aa27a1 100644
--- a/tests/fate/ffmpeg.mak
+++ b/tests/fate/ffmpeg.mak
@@ -109,7 +109,7 @@ FATE_SAMPLES_FFMPEG-$(call ALLYES, LAVFI_INDEV MOVIE_FILTER FILE_PROTOCOL \
                            += fate-ffmpeg-fix_sub_duration
 fate-ffmpeg-fix_sub_duration: CMD = fmtstdout srt -fix_sub_duration \
   -real_time 1 -f lavfi \
-  -i "movie=$(TARGET_SAMPLES)/sub/Closedcaption_rollup.m2v[out0+subcc]"
+  -i "movie=$(TARGET_SAMPLES)/sub/Closedcaption_rollup.m2v:dec_opts=export_side_data=a53cc[out0+subcc]"
 
 FATE_STREAMCOPY-$(call ALLYES, EAC3_DEMUXER MOV_MUXER) += fate-copy-trac3074
 fate-copy-trac3074: $(SAMPLES)/eac3/csi_miami_stereo_128_spx.eac3
diff --git a/tests/fate/subtitles.mak b/tests/fate/subtitles.mak
index bc464edce6..bb1dc7434e 100644
--- a/tests/fate/subtitles.mak
+++ b/tests/fate/subtitles.mak
@@ -2,13 +2,13 @@ FATE_SUBTITLES_ASS-$(call ALLYES, AQTITLE_DEMUXER TEXT_DECODER ICONV) += fate-su
 fate-sub-aqtitle: CMD = fmtstdout ass -sub_charenc windows-1250 -i $(TARGET_SAMPLES)/sub/AQTitle_capability_tester.aqt
 
 FATE_SUBTITLES_ASS-$(call ALLYES, AVDEVICE LAVFI_INDEV CCAPTION_DECODER MOVIE_FILTER MPEGTS_DEMUXER) += fate-sub-cc
-fate-sub-cc: CMD = fmtstdout ass -f lavfi -i "movie=$(TARGET_SAMPLES)/sub/Closedcaption_rollup.m2v[out0+subcc]"
+fate-sub-cc: CMD = fmtstdout ass -f lavfi -i "movie=$(TARGET_SAMPLES)/sub/Closedcaption_rollup.m2v:dec_opts=export_side_data=a53cc[out0+subcc]"
 
 FATE_SUBTITLES_ASS-$(call ALLYES, AVDEVICE LAVFI_INDEV CCAPTION_DECODER MOVIE_FILTER MPEGTS_DEMUXER) += fate-sub-cc-realtime
-fate-sub-cc-realtime: CMD = fmtstdout ass -real_time 1 -f lavfi -i "movie=$(TARGET_SAMPLES)/sub/Closedcaption_rollup.m2v[out0+subcc]"
+fate-sub-cc-realtime: CMD = fmtstdout ass -real_time 1 -f lavfi -i "movie=$(TARGET_SAMPLES)/sub/Closedcaption_rollup.m2v:dec_opts=export_side_data=a53cc[out0+subcc]"
 
 FATE_SUBTITLES_ASS-$(call ALLYES, AVDEVICE LAVFI_INDEV CCAPTION_DECODER MOVIE_FILTER MPEGTS_DEMUXER) += fate-sub-cc-scte20
-fate-sub-cc-scte20: CMD = fmtstdout ass -f lavfi -i "movie=$(TARGET_SAMPLES)/sub/scte20.ts[out0+subcc]"
+fate-sub-cc-scte20: CMD = fmtstdout ass -f lavfi -i "movie=$(TARGET_SAMPLES)/sub/scte20.ts:dec_opts=export_side_data=scte20cc[out0+subcc]"
 
 FATE_SUBTITLES_ASS-$(call DEMDEC, ASS, ASS) += fate-sub-ass-to-ass-transcode
 fate-sub-ass-to-ass-transcode: CMD = fmtstdout ass -i $(TARGET_SAMPLES)/sub/1ededcbd7b.ass
-- 
2.35.1

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