示例#1
0
        public static XingHeader LoadXingHeader(Mp3Frame frame)
        {
            XingHeader xingHeader = new XingHeader();

            xingHeader.frame = frame;
            int num;

            if (frame.MpegVersion == MpegVersion.Version1)
            {
                if (frame.ChannelMode != ChannelMode.Mono)
                {
                    num = 36;
                }
                else
                {
                    num = 21;
                }
            }
            else
            {
                if (frame.MpegVersion != MpegVersion.Version2)
                {
                    return(null);
                }
                if (frame.ChannelMode != ChannelMode.Mono)
                {
                    num = 21;
                }
                else
                {
                    num = 13;
                }
            }
            if (frame.RawData[num] == 88 && frame.RawData[num + 1] == 105 && frame.RawData[num + 2] == 110 && frame.RawData[num + 3] == 103)
            {
                xingHeader.startOffset = num;
                num += 4;
                int arg_9E_0 = XingHeader.ReadBigEndian(frame.RawData, num);
                num += 4;
                if ((arg_9E_0 & 1) != 0)
                {
                    xingHeader.framesOffset = num;
                    num += 4;
                }
                if ((arg_9E_0 & 2) != 0)
                {
                    xingHeader.bytesOffset = num;
                    num += 4;
                }
                if ((arg_9E_0 & 4) != 0)
                {
                    xingHeader.tocOffset = num;
                    num += 100;
                }
                if ((arg_9E_0 & 8) != 0)
                {
                    xingHeader.vbrScale = XingHeader.ReadBigEndian(frame.RawData, num);
                    num += 4;
                }
                xingHeader.endOffset = num;
                return(xingHeader);
            }
            return(null);
        }
示例#2
0
        private static bool IsValidHeader(byte[] headerBytes, Mp3Frame frame)
        {
            if (headerBytes[0] != 255 || (headerBytes[1] & 224) != 224)
            {
                return(false);
            }
            frame.MpegVersion = (MpegVersion)((headerBytes[1] & 24) >> 3);
            if (frame.MpegVersion == MpegVersion.Reserved)
            {
                return(false);
            }
            frame.MpegLayer = (MpegLayer)((headerBytes[1] & 6) >> 1);
            if (frame.MpegLayer == MpegLayer.Reserved)
            {
                return(false);
            }
            int num = (frame.MpegLayer == MpegLayer.Layer1) ? 0 : ((frame.MpegLayer == MpegLayer.Layer2) ? 1 : 2);

            frame.CrcPresent   = ((headerBytes[1] & 1) == 0);
            frame.BitRateIndex = (headerBytes[2] & 240) >> 4;
            if (frame.BitRateIndex == 15)
            {
                return(false);
            }
            int num2 = (frame.MpegVersion == MpegVersion.Version1) ? 0 : 1;

            frame.BitRate = Mp3Frame.bitRates[num2, num, frame.BitRateIndex] * 1000;
            if (frame.BitRate == 0)
            {
                return(false);
            }
            int num3 = (headerBytes[2] & 12) >> 2;

            if (num3 == 3)
            {
                return(false);
            }
            if (frame.MpegVersion == MpegVersion.Version1)
            {
                frame.SampleRate = Mp3Frame.sampleRatesVersion1[num3];
            }
            else if (frame.MpegVersion == MpegVersion.Version2)
            {
                frame.SampleRate = Mp3Frame.sampleRatesVersion2[num3];
            }
            else
            {
                frame.SampleRate = Mp3Frame.sampleRatesVersion25[num3];
            }
            bool flag      = (headerBytes[2] & 2) == 2;
            byte arg_123_0 = headerBytes[2];

            frame.ChannelMode      = (ChannelMode)((headerBytes[3] & 192) >> 6);
            frame.ChannelExtension = (headerBytes[3] & 48) >> 4;
            if (frame.ChannelExtension != 0 && frame.ChannelMode != ChannelMode.JointStereo)
            {
                return(false);
            }
            frame.Copyright = ((headerBytes[3] & 8) == 8);
            byte arg_167_0 = headerBytes[3];
            byte arg_16B_0 = headerBytes[3];
            int  num4      = flag ? 1 : 0;

            frame.SampleCount = Mp3Frame.samplesPerFrame[num2, num];
            int num5 = frame.SampleCount / 8;

            if (frame.MpegLayer == MpegLayer.Layer1)
            {
                frame.FrameLength = (num5 * frame.BitRate / frame.SampleRate + num4) * 4;
            }
            else
            {
                frame.FrameLength = num5 * frame.BitRate / frame.SampleRate + num4;
            }
            return(frame.FrameLength <= 16384);
        }
示例#3
0
        public override int Read(byte[] sampleBuffer, int offset, int numBytes)
        {
            int    i   = 0;
            object obj = this.repositionLock;

            lock (obj)
            {
                if (this.decompressLeftovers != 0)
                {
                    int num = Math.Min(this.decompressLeftovers, numBytes);
                    Array.Copy(this.decompressBuffer, this.decompressBufferOffset, sampleBuffer, offset, num);
                    this.decompressLeftovers -= num;
                    if (this.decompressLeftovers == 0)
                    {
                        this.decompressBufferOffset = 0;
                    }
                    else
                    {
                        this.decompressBufferOffset += num;
                    }
                    i      += num;
                    offset += num;
                }
                int num2 = this.tocIndex;
                if (this.repositionedFlag)
                {
                    this.decompressor.Reset();
                    this.tocIndex           = Math.Max(0, this.tocIndex - 3);
                    this.mp3Stream.Position = this.tableOfContents[this.tocIndex].FilePosition;
                    this.repositionedFlag   = false;
                }
                while (i < numBytes)
                {
                    Mp3Frame mp3Frame = this.ReadNextFrame(true);
                    if (mp3Frame == null)
                    {
                        break;
                    }
                    int num3 = this.decompressor.DecompressFrame(mp3Frame, this.decompressBuffer, 0);
                    if (this.tocIndex > num2 && num3 != 0)
                    {
                        if (this.tocIndex == num2 + 1 && num3 == this.bytesPerDecodedFrame * 2)
                        {
                            Array.Copy(this.decompressBuffer, this.bytesPerDecodedFrame, this.decompressBuffer, 0, this.bytesPerDecodedFrame);
                            num3 = this.bytesPerDecodedFrame;
                        }
                        int num4 = Math.Min(num3 - this.decompressBufferOffset, numBytes - i);
                        Array.Copy(this.decompressBuffer, this.decompressBufferOffset, sampleBuffer, offset, num4);
                        if (num4 + this.decompressBufferOffset < num3)
                        {
                            this.decompressBufferOffset = num4 + this.decompressBufferOffset;
                            this.decompressLeftovers    = num3 - this.decompressBufferOffset;
                        }
                        else
                        {
                            this.decompressBufferOffset = 0;
                            this.decompressLeftovers    = 0;
                        }
                        offset += num4;
                        i      += num4;
                    }
                }
            }
            this.position += (long)i;
            return(i);
        }
示例#4
0
 public static Mp3Frame LoadFromStream(Stream input)
 {
     return(Mp3Frame.LoadFromStream(input, true));
 }
示例#5
0
 private Mp3FileReader(Stream inputStream, Mp3FileReader.FrameDecompressorBuilder frameDecompressorBuilder, bool ownInputStream)
 {
     if (inputStream == null)
     {
         throw new ArgumentNullException("inputStream");
     }
     if (frameDecompressorBuilder == null)
     {
         throw new ArgumentNullException("frameDecompressorBuilder");
     }
     this.ownInputStream = ownInputStream;
     try
     {
         this.mp3Stream         = inputStream;
         this.Id3v2Tag          = Id3v2Tag.ReadTag(this.mp3Stream);
         this.dataStartPosition = this.mp3Stream.Position;
         Mp3Frame mp3Frame = Mp3Frame.LoadFromStream(this.mp3Stream);
         if (mp3Frame == null)
         {
             throw new InvalidDataException("Invalid MP3 file - no MP3 Frames Detected");
         }
         double num = (double)mp3Frame.BitRate;
         this.xingHeader = XingHeader.LoadXingHeader(mp3Frame);
         if (this.xingHeader != null)
         {
             this.dataStartPosition = this.mp3Stream.Position;
         }
         Mp3Frame mp3Frame2 = Mp3Frame.LoadFromStream(this.mp3Stream);
         if (mp3Frame2 != null && (mp3Frame2.SampleRate != mp3Frame.SampleRate || mp3Frame2.ChannelMode != mp3Frame.ChannelMode))
         {
             this.dataStartPosition = mp3Frame2.FileOffset;
             mp3Frame = mp3Frame2;
         }
         this.mp3DataLength      = this.mp3Stream.Length - this.dataStartPosition;
         this.mp3Stream.Position = this.mp3Stream.Length - 128L;
         byte[] array = new byte[128];
         this.mp3Stream.Read(array, 0, 128);
         if (array[0] == 84 && array[1] == 65 && array[2] == 71)
         {
             this.Id3v1Tag       = array;
             this.mp3DataLength -= 128L;
         }
         this.mp3Stream.Position = this.dataStartPosition;
         this.Mp3WaveFormat      = new Mp3WaveFormat(mp3Frame.SampleRate, (mp3Frame.ChannelMode == ChannelMode.Mono) ? 1 : 2, mp3Frame.FrameLength, (int)num);
         this.CreateTableOfContents();
         this.tocIndex             = 0;
         num                       = (double)this.mp3DataLength * 8.0 / this.TotalSeconds();
         this.mp3Stream.Position   = this.dataStartPosition;
         this.Mp3WaveFormat        = new Mp3WaveFormat(mp3Frame.SampleRate, (mp3Frame.ChannelMode == ChannelMode.Mono) ? 1 : 2, mp3Frame.FrameLength, (int)num);
         this.decompressor         = frameDecompressorBuilder(this.Mp3WaveFormat);
         this.waveFormat           = this.decompressor.OutputFormat;
         this.bytesPerSample       = this.decompressor.OutputFormat.BitsPerSample / 8 * this.decompressor.OutputFormat.Channels;
         this.bytesPerDecodedFrame = 1152 * this.bytesPerSample;
         this.decompressBuffer     = new byte[this.bytesPerDecodedFrame * 2];
     }
     catch (Exception)
     {
         if (ownInputStream)
         {
             inputStream.Dispose();
         }
         throw;
     }
 }