public int Read(int count)
{
int offset = ReadCache(count, 0);
while (count - offset > 0)
{
if (FFmpeg.av_read_frame(FormatPointer, PacketPointer) < 0)
{
break;
}
FFmpeg.AVPacket packet = (FFmpeg.AVPacket)Marshal.PtrToStructure(PacketPointer, typeof(FFmpeg.AVPacket));
Cache.Position = 0;
CacheOffset = 0;
CacheLength = 0;
while (packet.size > 0)
{
int datasize = FFmpegBufferSize;
int used = FFmpeg.avcodec_decode_audio2(AVStream.codec, FFmpegBuffer, ref datasize, packet.data, packet.size);
packet.size -= used;
packet.data = new IntPtr(packet.data.ToInt32() + used);
if (datasize <= 0)
{
break;
}
int read = Math.Max(Math.Min(datasize, (count - offset) * 2 * Channels), 0);
int left = datasize - read;
if (read > 0)
{
int samples = read / 2 / Channels;
short[] bitstream = new short[read / 2];
Marshal.Copy(FFmpegBuffer, bitstream, 0, read / 2);
AudioBuffer.DeinterlaceFrom(bitstream, samples, offset);
offset += samples;
}
if (left > 0)
{
Marshal.Copy(new IntPtr(FFmpegBuffer.ToInt32() + read), CacheBuffer, 0, left);
Cache.Write(CacheBuffer, read, left);
CacheLength += left;
}
}
}
return(offset);
}
private int ReadCache(int count, int offset)
{
Cache.Position = CacheOffset;
int bytesize = Math.Min((count - offset) * 2 * Channels, CacheLength - CacheOffset);
if (bytesize <= 0)
{
return(offset);
}
short[] bitstream = new short[bytesize / 2];
int samples = bytesize / 2 / Channels;
Buffer.BlockCopy(Cache.GetBuffer(), CacheOffset, bitstream, 0, bytesize);
AudioBuffer.DeinterlaceFrom(bitstream, samples, offset);
offset += samples;
CacheOffset += bytesize;
return(offset);
}
