libx264: copy A53 closed captions from source

Assumes 'GA94' format (ATSC standard)

Signed-off-by: DHE <git@dehacked.net>
Tested-by: Anshul <anshul.ffmpeg@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
DeHackEd 2015-09-29 13:19:34 -04:00 committed by Michael Niedermayer
parent f827a17005
commit e06114fed3
2 changed files with 49 additions and 0 deletions

View File

@ -2069,6 +2069,10 @@ For example to specify libx264 encoding options with @command{ffmpeg}:
ffmpeg -i foo.mpg -vcodec libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv
@end example
@item a53cc @var{boolean}
Import closed captions (which must be ATSC compatible format) into output.
Only the mpeg2 and h264 decoders provide these. Default is 0 (off).
@item x264-params (N.A.)
Override the x264 configuration using a :-separated list of key=value
parameters.

View File

@ -25,6 +25,7 @@
#include "libavutil/mem.h"
#include "libavutil/pixdesc.h"
#include "libavutil/stereo3d.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "internal.h"
@ -83,6 +84,7 @@ typedef struct X264Context {
int avcintra_class;
int motion_est;
int forced_idr;
int a53_cc;
char *x264_params;
} X264Context;
@ -256,6 +258,7 @@ static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
int nnal, i, ret;
x264_picture_t pic_out = {0};
int pict_type;
AVFrameSideData *side_data;
x264_picture_init( &x4->pic );
x4->pic.img.i_csp = x4->params.i_csp;
@ -287,7 +290,48 @@ static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
break;
}
reconfig_encoder(ctx, frame);
if (x4->a53_cc) {
side_data = av_frame_get_side_data(frame, AV_FRAME_DATA_A53_CC);
if (side_data) {
x4->pic.extra_sei.payloads = av_mallocz(sizeof(x4->pic.extra_sei.payloads[0]));
if (x4->pic.extra_sei.payloads == NULL) {
av_log(ctx, AV_LOG_ERROR, "Not enough memory for closed captions, skipping\n");
goto skip_a53cc;
}
x4->pic.extra_sei.sei_free = av_free;
x4->pic.extra_sei.payloads[0].payload_size = side_data->size + 11;
x4->pic.extra_sei.payloads[0].payload = av_mallocz(x4->pic.extra_sei.payloads[0].payload_size);
if (x4->pic.extra_sei.payloads[0].payload == NULL) {
av_log(ctx, AV_LOG_ERROR, "Not enough memory for closed captions, skipping\n");
av_freep(&x4->pic.extra_sei.payloads);
goto skip_a53cc;
}
x4->pic.extra_sei.num_payloads = 1;
x4->pic.extra_sei.payloads[0].payload_type = 4;
memcpy(x4->pic.extra_sei.payloads[0].payload + 10, side_data->data, side_data->size);
x4->pic.extra_sei.payloads[0].payload[0] = 181;
x4->pic.extra_sei.payloads[0].payload[1] = 0;
x4->pic.extra_sei.payloads[0].payload[2] = 49;
/**
* 'GA94' is standard in North America for ATSC, but hard coding
* this style may not be the right thing to do -- other formats
* do exist. This information is not available in the side_data
* so we are going with this right now.
*/
AV_WL32(x4->pic.extra_sei.payloads[0].payload + 3,
MKTAG('G', 'A', '9', '4'));
x4->pic.extra_sei.payloads[0].payload[7] = 3;
x4->pic.extra_sei.payloads[0].payload[8] =
((side_data->size/3) & 0x1f) | 0x40;
x4->pic.extra_sei.payloads[0].payload[9] = 0;
x4->pic.extra_sei.payloads[0].payload[side_data->size+10] = 255;
}
}
}
skip_a53cc:
do {
if (x264_encoder_encode(x4->enc, &nal, &nnal, frame? &x4->pic: NULL, &pic_out) < 0)
return AVERROR_EXTERNAL;
@ -830,6 +874,7 @@ static const AVOption options[] = {
{"level", "Specify level (as defined by Annex A)", OFFSET(level), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, VE},
{"passlogfile", "Filename for 2 pass stats", OFFSET(stats), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, VE},
{"wpredp", "Weighted prediction for P-frames", OFFSET(wpredp), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, VE},
{"a53cc", "Use A53 Closed Captions (if available)", OFFSET(a53_cc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, VE},
{"x264opts", "x264 options", OFFSET(x264opts), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, VE},
{ "crf", "Select the quality for constant quality mode", OFFSET(crf), AV_OPT_TYPE_FLOAT, {.dbl = -1 }, -1, FLT_MAX, VE },
{ "crf_max", "In CRF mode, prevents VBV from lowering quality beyond this point.",OFFSET(crf_max), AV_OPT_TYPE_FLOAT, {.dbl = -1 }, -1, FLT_MAX, VE },