Пример #1
0
        /// <summary>
        /// Positions the stream at the start of the next frame.
        /// </summary>
        /// <param name="syncWord"></param>
        /// <returns></returns>
        private void SeekNextFrame(SyncWord syncWord)
        {
            const int bytesPerSample = 4;
            const int bytesPerWord   = 2;
            const int channelCount   = 2;

            long streamLength    = Bass.BASS_ChannelGetLength(_handle);
            long currentPosition = 0;

            if (streamLength > 0)
            {
                currentPosition = Bass.BASS_ChannelGetPosition(_handle);
            }

            SyncFifoBuffer syncFifoBuffer = new SyncFifoBuffer(syncWord);

            float[] readBuffer = new float[channelCount];

            bool success        = false;
            int  sampleIndex    = 0;
            int  maxSampleIndex = (syncWord.MaxFrameSize / bytesPerWord) + syncWord.WordLength;

            while (!success && sampleIndex < maxSampleIndex)
            {
                // For float streams we get one float value for each 16bit word
                int bytesRead = Bass.BASS_ChannelGetData(_handle, readBuffer, readBuffer.Length * bytesPerSample);
                if (bytesRead <= 0)
                {
                    // End of stream
                    break;
                }
                int samplesRead = bytesRead / bytesPerSample;
                int readSample  = 0;
                while (!success && readSample < samplesRead)
                {
                    // Convert float value to word
                    UInt16 word = (UInt16)(readBuffer[readSample] * 32768);

                    // Add word to fifo buffer
                    syncFifoBuffer.Write(word);

                    // Check Sync word
                    if (syncFifoBuffer.IsMatch())
                    {
                        long pos = currentPosition + (sampleIndex - syncWord.WordLength + 1) * bytesPerWord;
                        Bass.BASS_ChannelSetPosition(_handle, pos);
                        success = true;
                    }
                    sampleIndex++;
                    readSample++;
                }
            }

            if (!success && streamLength > 0)
            {
                Bass.BASS_ChannelSetPosition(_handle, currentPosition);
            }
        }
Пример #2
0
    /// <summary>
    /// Positions the stream at the start of the next frame.
    /// </summary>
    /// <param name="syncWord"></param>
    /// <returns></returns>
    private void SeekNextFrame(SyncWord syncWord)
    {
      const int bytesPerSample = 4;
      const int bytesPerWord = 2;
      const int channelCount = 2;

      long streamLength = Bass.BASS_ChannelGetLength(_handle);
      long currentPosition = 0;
      if (streamLength > 0)
        currentPosition = Bass.BASS_ChannelGetPosition(_handle);

      SyncFifoBuffer syncFifoBuffer = new SyncFifoBuffer(syncWord);
      float[] readBuffer = new float[channelCount];

      bool success = false;
      int sampleIndex = 0;
      int maxSampleIndex = (syncWord.MaxFrameSize / bytesPerWord) + syncWord.WordLength;

      while (!success && sampleIndex < maxSampleIndex)
      {
        // For float streams we get one float value for each 16bit word
        int bytesRead = Bass.BASS_ChannelGetData(_handle, readBuffer, readBuffer.Length * bytesPerSample);
        if (bytesRead <= 0)
          // End of stream
          break;
        int samplesRead = bytesRead / bytesPerSample;
        int readSample = 0;
        while (!success && readSample < samplesRead)
        {
          // Convert float value to word
          UInt16 word = (UInt16)(readBuffer[readSample] * 32768);

          // Add word to fifo buffer
          syncFifoBuffer.Write(word);

          // Check Sync word
          if (syncFifoBuffer.IsMatch())
          {
            long pos = currentPosition + (sampleIndex - syncWord.WordLength + 1) * bytesPerWord;
            Bass.BASS_ChannelSetPosition(_handle, pos);
            success = true;
          }
          sampleIndex++;
          readSample++;
        }
      }

      if (!success && streamLength > 0)
        Bass.BASS_ChannelSetPosition(_handle, currentPosition);
    }
Пример #3
0
    /// <summary>
    /// Determines if the stream contains frames with the specified syncwords. 
    /// </summary>
    /// <param name="syncWord">Syncword to search for.</param>
    /// <returns></returns>
    private bool IsEncoded(SyncWord syncWord)
    {
      const int framesToCheck = 5;
      const int bytesPerSample = 4;
      const int bytesPerWord = 2;
      const int channelCount = 2;

      long streamLength = Bass.BASS_ChannelGetLength(_handle);
      long currentPosition = 0;
      if (streamLength > 0)
      {
        currentPosition = Bass.BASS_ChannelGetPosition(_handle);
        if (currentPosition != 0)
          Bass.BASS_ChannelSetPosition(_handle, 0);
      }

      SyncFifoBuffer syncFifoBuffer = new SyncFifoBuffer(syncWord);
      float[] readBuffer = new float[channelCount];

      int lastSyncWordPosition = -1;
      int lastFrameSize = -1;
      int frameCount = 0;

      bool result = false;
      int sampleIndex = 0;
      int maxSampleIndex = (syncWord.MaxFrameSize / bytesPerWord) * framesToCheck + syncWord.WordLength;

      while (!result && sampleIndex < maxSampleIndex)
      {
        int bytesRead = Bass.BASS_ChannelGetData(_handle, readBuffer, readBuffer.Length * bytesPerSample);
        if (bytesRead <= 0)
          // End of stream
          break;
        int samplesRead = bytesRead / bytesPerSample;
        int readSample = 0;
        while (!result && readSample < samplesRead)
        {
          // Convert float value to word
          UInt16 word = (UInt16)(readBuffer[readSample] * 32768);

          // Add word to fifo buffer
          syncFifoBuffer.Write(word);

          // Check Sync word
          if (syncFifoBuffer.IsMatch())
          {
            int newSyncWordPosition = (sampleIndex - syncWord.WordLength + 1) * bytesPerWord;
            if (lastSyncWordPosition != -1)
            {
              int thisFrameSize = newSyncWordPosition - lastSyncWordPosition;
              if (lastFrameSize != -1)
              {
                if (thisFrameSize != lastFrameSize)
                  break;
              }
              lastFrameSize = thisFrameSize;
              frameCount++;
            }
            lastSyncWordPosition = newSyncWordPosition;
            result = (frameCount == framesToCheck);
          }
          sampleIndex++;
          readSample++;
        }
      }

      if (streamLength > 0)
        Bass.BASS_ChannelSetPosition(_handle, currentPosition);

      return result;
    }
Пример #4
0
        /// <summary>
        /// Determines if the stream contains frames with the specified syncwords.
        /// </summary>
        /// <param name="syncWord">Syncword to search for.</param>
        /// <returns></returns>
        private bool IsEncoded(SyncWord syncWord)
        {
            const int framesToCheck  = 5;
            const int bytesPerSample = 4;
            const int bytesPerWord   = 2;
            const int channelCount   = 2;

            long streamLength    = Bass.BASS_ChannelGetLength(_handle);
            long currentPosition = 0;

            if (streamLength > 0)
            {
                currentPosition = Bass.BASS_ChannelGetPosition(_handle);
                if (currentPosition != 0)
                {
                    Bass.BASS_ChannelSetPosition(_handle, 0);
                }
            }

            SyncFifoBuffer syncFifoBuffer = new SyncFifoBuffer(syncWord);

            float[] readBuffer = new float[channelCount];

            int lastSyncWordPosition = -1;
            int lastFrameSize        = -1;
            int frameCount           = 0;

            bool result         = false;
            int  sampleIndex    = 0;
            int  maxSampleIndex = (syncWord.MaxFrameSize / bytesPerWord) * framesToCheck + syncWord.WordLength;

            while (!result && sampleIndex < maxSampleIndex)
            {
                int bytesRead = Bass.BASS_ChannelGetData(_handle, readBuffer, readBuffer.Length * bytesPerSample);
                if (bytesRead <= 0)
                {
                    // End of stream
                    break;
                }
                int samplesRead = bytesRead / bytesPerSample;
                int readSample  = 0;
                while (!result && readSample < samplesRead)
                {
                    // Convert float value to word
                    UInt16 word = (UInt16)(readBuffer[readSample] * 32768);

                    // Add word to fifo buffer
                    syncFifoBuffer.Write(word);

                    // Check Sync word
                    if (syncFifoBuffer.IsMatch())
                    {
                        int newSyncWordPosition = (sampleIndex - syncWord.WordLength + 1) * bytesPerWord;
                        if (lastSyncWordPosition != -1)
                        {
                            int thisFrameSize = newSyncWordPosition - lastSyncWordPosition;
                            if (lastFrameSize != -1)
                            {
                                if (thisFrameSize != lastFrameSize)
                                {
                                    break;
                                }
                            }
                            lastFrameSize = thisFrameSize;
                            frameCount++;
                        }
                        lastSyncWordPosition = newSyncWordPosition;
                        result = (frameCount == framesToCheck);
                    }
                    sampleIndex++;
                    readSample++;
                }
            }

            if (streamLength > 0)
            {
                Bass.BASS_ChannelSetPosition(_handle, currentPosition);
            }

            return(result);
        }