diff options
author | Anton Khirnov <anton@khirnov.net> | 2014-06-18 20:42:52 +0200 |
---|---|---|
committer | Anton Khirnov <anton@khirnov.net> | 2016-02-23 17:01:58 +0100 |
commit | 9200514ad8717c63f82101dc394f4378854325bf (patch) | |
tree | 566b8d48565a88303363198acc81de06363daa7a /libavformat/rmenc.c | |
parent | a8068346e48e123f8d3bdf4d64464d81e53e5fc7 (diff) |
lavf: replace AVStream.codec with AVStream.codecpar
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.
In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.
There are multiple important problems with this approach:
- the fields in AVCodecContext are in general one of
* stream parameters
* codec options
* codec state
However, it's not clear which ones are which. It is consequently
unclear which fields are a demuxer allowed to set or a muxer allowed to
read. This leads to erratic behaviour depending on whether decoding or
encoding is being performed or not (and whether it uses the AVStream
embedded codec context).
- various synchronization issues arising from the fact that the same
context is used by several different APIs (muxers/demuxers,
parsers, bitstream filters and encoders/decoders) simultaneously, with
there being no clear rules for who can modify what and the different
processes being typically delayed with respect to each other.
- avformat_find_stream_info() making it necessary to support opening
and closing a single codec context multiple times, thus
complicating the semantics of freeing various allocated objects in the
codec context.
Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
Diffstat (limited to 'libavformat/rmenc.c')
-rw-r--r-- | libavformat/rmenc.c | 46 |
1 files changed, 23 insertions, 23 deletions
diff --git a/libavformat/rmenc.c b/libavformat/rmenc.c index bbfd550a3b..e4a0d60a42 100644 --- a/libavformat/rmenc.c +++ b/libavformat/rmenc.c @@ -33,7 +33,7 @@ typedef struct StreamInfo { int nb_frames; /* current frame number */ int total_frames; /* total number of frames */ int num; - AVCodecContext *enc; + AVCodecParameters *par; } StreamInfo; typedef struct RMMuxContext { @@ -147,7 +147,7 @@ static int rv10_write_header(AVFormatContext *ctx, stream = &rm->streams[i]; - if (stream->enc->codec_type == AVMEDIA_TYPE_AUDIO) { + if (stream->par->codec_type == AVMEDIA_TYPE_AUDIO) { desc = "The Audio Stream"; mimetype = "audio/x-pn-realaudio"; codec_data_size = 73; @@ -183,11 +183,11 @@ static int rv10_write_header(AVFormatContext *ctx, put_str8(s, mimetype); avio_wb32(s, codec_data_size); - if (stream->enc->codec_type == AVMEDIA_TYPE_AUDIO) { + if (stream->par->codec_type == AVMEDIA_TYPE_AUDIO) { int coded_frame_size, fscode, sample_rate; - int frame_size = av_get_audio_frame_duration(stream->enc, 0); - sample_rate = stream->enc->sample_rate; - coded_frame_size = (stream->enc->bit_rate * + int frame_size = av_get_audio_frame_duration2(stream->par, 0); + sample_rate = stream->par->sample_rate; + coded_frame_size = (stream->par->bit_rate * frame_size) / (8 * sample_rate); /* audio codec info */ avio_write(s, ".ra", 3); @@ -228,13 +228,13 @@ static int rv10_write_header(AVFormatContext *ctx, /* frame length : seems to be very important */ avio_wb16(s, coded_frame_size); avio_wb32(s, 0); /* unknown */ - avio_wb16(s, stream->enc->sample_rate); /* sample rate */ + avio_wb16(s, stream->par->sample_rate); /* sample rate */ avio_wb32(s, 0x10); /* unknown */ - avio_wb16(s, stream->enc->channels); + avio_wb16(s, stream->par->channels); put_str8(s, "Int0"); /* codec name */ - if (stream->enc->codec_tag) { + if (stream->par->codec_tag) { avio_w8(s, 4); /* tag length */ - avio_wl32(s, stream->enc->codec_tag); + avio_wl32(s, stream->par->codec_tag); } else { av_log(ctx, AV_LOG_ERROR, "Invalid codec tag\n"); return -1; @@ -247,12 +247,12 @@ static int rv10_write_header(AVFormatContext *ctx, /* video codec info */ avio_wb32(s,34); /* size */ ffio_wfourcc(s, "VIDO"); - if(stream->enc->codec_id == AV_CODEC_ID_RV10) + if(stream->par->codec_id == AV_CODEC_ID_RV10) ffio_wfourcc(s,"RV10"); else ffio_wfourcc(s,"RV20"); - avio_wb16(s, stream->enc->width); - avio_wb16(s, stream->enc->height); + avio_wb16(s, stream->par->width); + avio_wb16(s, stream->par->height); avio_wb16(s, (int) stream->frame_rate); /* frames per seconds ? */ avio_wb32(s,0); /* unknown meaning */ avio_wb16(s, (int) stream->frame_rate); /* unknown meaning */ @@ -261,7 +261,7 @@ static int rv10_write_header(AVFormatContext *ctx, /* Seems to be the codec version: only use basic H263. The next versions seems to add a diffential DC coding as in MPEG... nothing new under the sun */ - if(stream->enc->codec_id == AV_CODEC_ID_RV10) + if(stream->par->codec_id == AV_CODEC_ID_RV10) avio_wb32(s,0x10000000); else avio_wb32(s,0x20103001); @@ -312,25 +312,25 @@ static int rm_write_header(AVFormatContext *s) RMMuxContext *rm = s->priv_data; StreamInfo *stream; int n; - AVCodecContext *codec; + AVCodecParameters *par; for(n=0;n<s->nb_streams;n++) { AVStream *st = s->streams[n]; int frame_size; s->streams[n]->id = n; - codec = s->streams[n]->codec; + par = s->streams[n]->codecpar; stream = &rm->streams[n]; memset(stream, 0, sizeof(StreamInfo)); stream->num = n; - stream->bit_rate = codec->bit_rate; - stream->enc = codec; + stream->bit_rate = par->bit_rate; + stream->par = par; - switch(codec->codec_type) { + switch (par->codec_type) { case AVMEDIA_TYPE_AUDIO: rm->audio_stream = stream; - frame_size = av_get_audio_frame_duration(codec, 0); - stream->frame_rate = (float)codec->sample_rate / (float)frame_size; + frame_size = av_get_audio_frame_duration2(par, 0); + stream->frame_rate = (float)par->sample_rate / (float)frame_size; /* XXX: dummy values */ stream->packet_max_size = 1024; stream->nb_packets = 0; @@ -365,7 +365,7 @@ static int rm_write_audio(AVFormatContext *s, const uint8_t *buf, int size, int write_packet_header(s, stream, size, !!(flags & AV_PKT_FLAG_KEY)); - if (stream->enc->codec_id == AV_CODEC_ID_AC3) { + if (stream->par->codec_id == AV_CODEC_ID_AC3) { /* for AC-3, the words seem to be reversed */ for (i = 0; i < size; i += 2) { avio_w8(pb, buf[i + 1]); @@ -428,7 +428,7 @@ static int rm_write_video(AVFormatContext *s, const uint8_t *buf, int size, int static int rm_write_packet(AVFormatContext *s, AVPacket *pkt) { - if (s->streams[pkt->stream_index]->codec->codec_type == + if (s->streams[pkt->stream_index]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) return rm_write_audio(s, pkt->data, pkt->size, pkt->flags); else |