/// <inheritdoc />
public void Dispose()
{
if (isDisposed)
{
return;
}
isDisposed = true;
// Remove all streams
// Note: native streams are freed along the native context.
streams.Clear();
ClearStreamInfo();
if (!IsOpen || !FFmpegUtils.CheckPlatformSupport())
{
return;
}
ffmpeg.av_free(pDecodedFrame);
ffmpeg.av_free(pCpuCopyFrame);
ffmpeg.sws_freeContext(pConvertContext);
var pFormatContext = AVFormatContext;
ffmpeg.avformat_close_input(&pFormatContext);
ffmpeg.avformat_free_context(pFormatContext);
}
public bool SeekToTime([NotNull] FFmpegStream stream, long timestamp)
{
FFmpegUtils.EnsurePlatformSupport();
var skip_to_keyframe = stream.AVStream->skip_to_keyframe;
try
{
if (currentStreams.TryGetValue(stream, out var streamInfo))
{
// flush the codec buffered images
streamInfo.Codec.Flush(pDecodedFrame);
}
// flush the format buffered images
ffmpeg.avformat_flush(AVFormatContext);
// perform the actual seek
stream.AVStream->skip_to_keyframe = 1;
var ret = ffmpeg.av_seek_frame(AVFormatContext, stream.Index, timestamp, ffmpeg.AVSEEK_FLAG_BACKWARD);
if (ret < 0)
{
Logger.Error($"Could not seek frame. Error code={ret.ToString("X8")}");
Logger.Error(GetErrorMessage(ret));
return(false);
}
return(true);
}
finally
{
stream.AVStream->skip_to_keyframe = skip_to_keyframe;
}
}
/// <summary>
/// Initializes a new instance of the <see cref="FFmpegStream"/> class.
/// </summary>
protected FFmpegStream([NotNull] AVStream *pStream, FFmpegMedia media)
{
if (pStream == null)
{
throw new ArgumentNullException(nameof(pStream));
}
AVStream = pStream;
Codec = pStream->codec->codec_id;
Media = media;
Index = pStream->index;
Metadata = FFmpegUtils.ToDictionary(pStream->metadata);
}
public int ExtractFrames([NotNull] FFmpegStream stream, int count)
{
FFmpegUtils.EnsurePlatformSupport();
if (isDisposed)
{
throw new ObjectDisposedException(nameof(FFmpegMedia));
}
if (!IsOpen)
{
// TODO: log?
throw new InvalidOperationException(@"Media isn't open.");
}
var codecContext = *stream.AVStream->codec;
var streamInfo = GetStreamInfo(stream);
var dstData = new byte_ptrArray4();
var dstLinesize = new int_array4();
ffmpeg.av_image_fill_arrays(ref dstData, ref dstLinesize, (byte *)streamInfo.Image.Buffer, DestinationPixelFormat, codecContext.width, codecContext.height, 1);
streamInfo.Image.Linesize = dstLinesize[0];
var extractedFrameCount = 0;
var packet = new AVPacket();
var pPacket = &packet;
ffmpeg.av_init_packet(pPacket);
for (int i = 0; i < count; i++)
{
var extractionStatus = ExtractNextImage(streamInfo, pPacket, stream.AVStream, dstData, dstLinesize);
streamInfo.ReachedEnd = extractionStatus == FrameExtractionStatus.ReachEOF;
if (extractionStatus == FrameExtractionStatus.Succeeded)
{
++extractedFrameCount;
}
}
return(extractedFrameCount);
}
/// <summary>
/// Opens this media.
/// </summary>
/// <remarks>
/// Once the media is open, the collection of <see cref="Streams"/> is populated.
/// </remarks>
public void Open(string url, long startPosition = 0, long length = -1)
{
FFmpegUtils.EnsurePlatformSupport();
if (isDisposed)
{
throw new ObjectDisposedException(nameof(FFmpegMedia));
}
if (IsOpen)
{
// TODO: log?
throw new InvalidOperationException(@"Media is already open.");
}
if (startPosition != 0 && length != -1)
{
url = $@"subfile,,start,{startPosition},end,{startPosition + length},,:{url}";
}
var pFormatContext = ffmpeg.avformat_alloc_context();
var ret = ffmpeg.avformat_open_input(&pFormatContext, url, null, null);
if (ret < 0)
{
Logger.Error($"Could not open file. Error code={ret.ToString("X8")}");
Logger.Error(GetErrorMessage(ret));
throw new ApplicationException(@"Could not open file.");
}
ret = ffmpeg.avformat_find_stream_info(pFormatContext, null);
if (ret < 0)
{
Logger.Error($"Could not find stream info. Error code={ret.ToString("X8")}");
Logger.Error(GetErrorMessage(ret));
throw new ApplicationException(@"Could not find stream info.");
}
AVFormatContext = pFormatContext;
Duration = TimeSpan.FromSeconds((double)AVFormatContext->duration / ffmpeg.AV_TIME_BASE);
Url = url;
// Get the streams
for (int i = 0; i < pFormatContext->nb_streams; i++)
{
var stream = FFmpegStream.Create(pFormatContext->streams[i], this);
streams.Add(stream);
}
pDecodedFrame = ffmpeg.av_frame_alloc();
if (pDecodedFrame == null)
{
throw new ApplicationException("Couldn't allocate a frame for decoding.");
}
pCpuCopyFrame = ffmpeg.av_frame_alloc();
if (pCpuCopyFrame == null)
{
throw new ApplicationException("Couldn't allocate a frame for hardware decoding.");
}
// dispose cached video image from previous file
ClearStreamInfo();
}
