cmdutils: Add a stream specifier to map usable streams

It drops everything that cannot be used for re-encoding and/or
streamcopy.
This commit is contained in:
Luca Barbato 2015-03-18 13:40:12 +01:00
parent 30e6abd1a8
commit 342fc46c69
2 changed files with 25 additions and 0 deletions

View File

@ -1587,6 +1587,28 @@ int check_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec)
av_freep(&key);
return ret;
} else if (*spec == 'u') {
AVCodecContext *avctx = st->codec;
int val;
switch (avctx->codec_type) {
case AVMEDIA_TYPE_AUDIO:
val = avctx->sample_rate && avctx->channels;
if (avctx->sample_fmt == AV_SAMPLE_FMT_NONE)
return 0;
break;
case AVMEDIA_TYPE_VIDEO:
val = avctx->width && avctx->height;
if (avctx->pix_fmt == AV_PIX_FMT_NONE)
return 0;
break;
case AVMEDIA_TYPE_UNKNOWN:
val = 0;
break;
default:
val = 1;
break;
}
return avctx->codec_id != AV_CODEC_ID_NONE && val != 0;
} else if (!*spec) /* empty specifier, matches everything */
return 1;

View File

@ -48,6 +48,9 @@ Match the stream by stream id (e.g. PID in MPEG-TS container).
Matches streams with the metadata tag @var{key} having the specified value. If
@var{value} is not given, matches streams that contain the given tag with any
value.
@item u
Matches streams with usable configuration, the codec must be defined and the
essential information such as video dimension or audio sample rate must be present.
Note that in @command{avconv}, matching by metadata will only work properly for
input files.