public IEnumerable <MediaPacket> ReadPacket()
{
using (MediaPacket packet = new MediaPacket())
{
int ret;
do
{
ret = ReadPacket(packet);
if (ret < 0 && ret != ffmpeg.AVERROR_EOF)
{
throw new FFmpegException(ret);
}
yield return(packet);
packet.Clear();
} while (ret >= 0);
}
}
/// <summary>
/// TODO: add SubtitleFrame support
/// </summary>
/// <param name="frame"></param>
/// <returns></returns>
public virtual IEnumerable <MediaPacket> EncodeFrame(MediaFrame frame)
{
SendFrame(frame).ThrowIfError();
RemoveSideData(frame);
using (MediaPacket packet = new MediaPacket())
{
while (true)
{
int ret = ReceivePacket(packet);
if (ret == ffmpeg.AVERROR(ffmpeg.EAGAIN) || ret == ffmpeg.AVERROR_EOF)
{
break;
}
ret.ThrowIfError();
yield return(packet);
}
}
}
/// <summary>
/// decode packet to get frame.
/// TODO: add SubtitleFrame support
/// <para>
/// <see cref="SendPacket(MediaPacket)"/> and <see cref="ReceiveFrame(MediaFrame)"/>
/// </para>
/// </summary>
/// <param name="packet"></param>
/// <returns></returns>
public virtual IEnumerable <MediaFrame> DecodePacket(MediaPacket packet)
{
if (SendPacket(packet) >= 0)
{
// if codoc type is video, create new video frame
// else if codoc type is audio, create new audio frame
// else throw a exception (e.g. codec type is subtitle)
// TODO: add subtitle supported
using (MediaFrame frame =
Type == AVMediaType.AVMEDIA_TYPE_VIDEO ?
new VideoFrame() :
Type == AVMediaType.AVMEDIA_TYPE_AUDIO ?
(MediaFrame) new AudioFrame() :
throw new FFmpegException(FFmpegException.NotSupportFrame))
{
while (ReceiveFrame(frame) >= 0)
{
yield return(frame);
}
}
}
}
public int ReceivePacket([Out] MediaPacket packet)
{
return(ffmpeg.avcodec_receive_packet(pCodecContext, packet));
}
public int ReadPacket([Out] MediaPacket packet)
{
return(ffmpeg.av_read_frame(pFormatContext, packet));
}