public VideoWriter(string filename)
{
Filename = filename;
videoStream = new OutputStream();
audioStream = new OutputStream();
}
private void AddStream(ref OutputStream stream, ref AVCodec *codec, AVCodecID codecId)
{
AVCodecContext *c;
codec = avcodec_find_encoder(codecId);
if (codec == null)
{
throw new NotSupportedException("No encoder for codec " + avcodec_get_name(codecId));
}
stream.st = avformat_new_stream(ctx, null);
if (stream.st == null)
{
throw new FFmpegException("Could not allocate stream");
}
stream.st->id = (int)(ctx->nb_streams - 1);
c = avcodec_alloc_context3(codec);
if (c == null)
{
throw new FFmpegException("Could not allocate encoding context");
}
stream.enc = c;
if (codec->type == AVMediaType.AVMEDIA_TYPE_AUDIO)
{
c->sample_fmt = codec->sample_fmts != null ? codec->sample_fmts[0] : AVSampleFormat.AV_SAMPLE_FMT_FLTP;
c->bit_rate = AudioBitrate;
c->sample_rate = AudioSampleRate;
c->channels = av_get_channel_layout_nb_channels(c->channel_layout);
c->channel_layout = AV_CH_LAYOUT_STEREO;
if (codec->channel_layouts != null)
{
c->channel_layout = codec->channel_layouts[0];
for (int i = 0; codec->channel_layouts[i] != 0; i++)
{
if (codec->channel_layouts[i] == AV_CH_LAYOUT_STEREO)
{
c->channel_layout = AV_CH_LAYOUT_STEREO;
}
}
}
c->channels = av_get_channel_layout_nb_channels(c->channel_layout);
stream.st->time_base = new AVRational()
{
num = 1, den = c->sample_rate
};
}
else if (codec->type == AVMediaType.AVMEDIA_TYPE_VIDEO)
{
c->codec_id = codecId;
c->bit_rate = VideoBitrate;
c->width = Width;
c->height = Height;
stream.st->time_base = new AVRational()
{
num = 1, den = Fps
};
c->time_base = stream.st->time_base;
c->gop_size = 12;
c->pix_fmt = AVPixelFormat.AV_PIX_FMT_YUV420P;
if (c->codec_id == AVCodecID.AV_CODEC_ID_MPEG1VIDEO)
{
c->mb_decision = 2;
}
}
if ((ctx->oformat->flags & AVFMT_GLOBALHEADER) != 0)
{
c->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
}
}
