protected override void PrepareInternal() { base.PrepareInternal(); begin = true; if (byteBuffer != null) { return; } compressedSoundStream.Position = 0; currentPacketIndex = 0; startPktSampleIndex = 0; endPktSampleIndex = 0; endPacketIndex = numberOfPackets; PlayRange range; lock (rangeLock) { range = playRange; } // Reset decoder state decoder.ResetDecoder(); // Ignore invalid data at beginning (due to encoder delay) & end of stream (due to packet size) var samplesToSkip = decoder.GetDecoderSampleDelay(); var frameSize = SamplesPerFrame * channels; //ok we need to handle this case properly, this means that the user wants to use a different then full audio stream range... var sampleStart = (channels * samplesToSkip) + (int)Math.Floor(sampleRate * (double)channels * range.Start.TotalSeconds); startPktSampleIndex = sampleStart % (frameSize); var sampleStop = (channels * samplesToSkip) + (range.Length != TimeSpan.Zero ? (int)Math.Floor(sampleRate * (double)channels * range.End.TotalSeconds) : (channels * samples)); endPktSampleIndex = frameSize - sampleStop % frameSize; var skipCounter = startingPacketIndex = sampleStart / frameSize; endPacketIndex = sampleStop / frameSize; // skip to the starting packet if (startingPacketIndex < numberOfPackets && endPacketIndex < numberOfPackets && startingPacketIndex < endPacketIndex) { //valid offsets.. process it while (skipCounter-- > 0) { //skip data to reach starting packet var len = reader.ReadInt16(); compressedSoundStream.Position = compressedSoundStream.Position + len; currentPacketIndex++; } } }
protected override void PrepareInternal() { base.PrepareInternal(); begin = true; if (byteBuffer != null) { return; } compressedSoundStream.Position = 0; currentPacketIndex = 0; startPktSampleIndex = 0; endPktSampleIndex = 0; endPacketIndex = numberOfPackets; PlayRange range; lock (rangeLock) { range = playRange; } // Reset decoder state decoder.ResetDecoder(); // Ignore invalid data at beginning (due to encoder delay) & end of stream (due to packet size) var samplesToSkip = decoder.GetDecoderSampleDelay(); // Compute boundaries var sampleBegin = (channels * samplesToSkip); var sampleEnd = sampleBegin + (channels * samples); var frameSize = SamplesPerFrame * channels; //ok we need to handle this case properly, this means that the user wants to use a different then full audio stream range... var sampleStart = sampleBegin + (int)Math.Floor(sampleRate * (double)channels * range.Start.TotalSeconds); // Make sure start is at least one sample before the end to avoid edge cases where startingPacketIndex == numberOfPackets sampleStart = Math.Min(Math.Max(sampleStart, sampleBegin), sampleEnd - 1 * channels); var sampleStop = sampleBegin + (range.Length != TimeSpan.Zero ? (int)Math.Floor(sampleRate * (double)channels * range.End.TotalSeconds) : (channels * samples)); // Make sure stop is at least one sample after start sampleStop = Math.Min(Math.Max(sampleStop, sampleStart + 1 * channels), sampleEnd); // Compute start/end packet startingPacketIndex = sampleStart / frameSize; endPacketIndex = (sampleStop - 1) / frameSize; // -1 to make sure we stay in last packet if using all of it // How much data to use in start/end packet startPktSampleIndex = sampleStart % (frameSize); endPktSampleIndex = frameSize - sampleStop % frameSize; // skip to the starting packet if (startingPacketIndex < numberOfPackets && endPacketIndex < numberOfPackets && startingPacketIndex <= endPacketIndex) // this shouldn't happen anymore with the min/max clamps { //valid offsets.. process it var skipCounter = startingPacketIndex; while (skipCounter-- > 0) { //skip data to reach starting packet var len = reader.ReadInt16(); compressedSoundStream.Position = compressedSoundStream.Position + len; currentPacketIndex++; } } }