mirror of
https://github.com/SubtitleEdit/subtitleedit.git
synced 2024-10-28 06:52:35 +01:00
638 lines
24 KiB
C#
638 lines
24 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Drawing;
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using System.Globalization;
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using System.IO;
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using System.Text;
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using System.Xml;
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namespace Nikse.SubtitleEdit.Core
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{
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/// <summary>
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/// http://www-mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/WAVE.html
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/// </summary>
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public class WaveHeader
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{
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private const int ConstantHeaderSize = 20;
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private readonly byte[] _headerData;
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public string ChunkId { get; private set; }
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public uint ChunkSize { get; private set; }
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public string Format { get; private set; }
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public string FmtId { get; private set; }
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public int FmtChunkSize { get; private set; }
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/// <summary>
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/// 1 = PCM (uncompressed)
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/// 0x0101 = IBM mu-law format
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/// 0x0102 = IBM a-law format
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/// 0x0103 = IBM AVC Adaptive Differential Pulse Code Modulation format
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/// 0xFFFE = WAVE_FORMAT_EXTENSIBLE, Determined by SubFormat
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/// </summary>
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public int AudioFormat { get; private set; }
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public int NumberOfChannels { get; private set; }
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/// <summary>
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/// Number of samples per second
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/// </summary>
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public int SampleRate { get; private set; }
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/// <summary>
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/// Should be SampleRate * BlockAlign
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/// </summary>
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public int ByteRate { get; private set; }
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/// <summary>
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/// 8 bytes per block (32 bit); 6 bytes per block (24 bit); 4 bytes per block (16 bit)
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/// </summary>
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public int BlockAlign { get; private set; }
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public int BitsPerSample { get; private set; }
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public string DataId { get; private set; }
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/// <summary>
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/// Size of sound data
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/// </summary>
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public uint DataChunkSize { get; private set; }
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public int DataStartPosition { get; private set; }
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public WaveHeader(Stream stream)
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{
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stream.Position = 0;
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var buffer = new byte[ConstantHeaderSize];
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int bytesRead = stream.Read(buffer, 0, buffer.Length);
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if (bytesRead < buffer.Length)
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throw new ArgumentException("Stream is too small");
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// constant header
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ChunkId = Encoding.UTF8.GetString(buffer, 0, 4); // Chunk ID: "RIFF" (Resource Interchange File Format), RF64 = new 64-bit format - see http://tech.ebu.ch/docs/tech/tech3306-2009.pdf
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ChunkSize = BitConverter.ToUInt32(buffer, 4); // Chunk size: 16 or 18 or 40
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Format = Encoding.UTF8.GetString(buffer, 8, 4); // Format code - "WAVE"
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FmtId = Encoding.UTF8.GetString(buffer, 12, 4); // Contains the letters "fmt "
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FmtChunkSize = BitConverter.ToInt32(buffer, 16); // 16 for PCM. This is the size of the rest of the Subchunk which follows this number.
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// fmt data
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buffer = new byte[FmtChunkSize];
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stream.Read(buffer, 0, buffer.Length);
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AudioFormat = BitConverter.ToInt16(buffer, 0); // PCM = 1
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NumberOfChannels = BitConverter.ToInt16(buffer, 2);
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SampleRate = BitConverter.ToInt32(buffer, 4); // 8000, 44100, etc.
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ByteRate = BitConverter.ToInt32(buffer, 8); // SampleRate * NumChannels * BitsPerSample/8
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BlockAlign = BitConverter.ToInt16(buffer, 12);
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BitsPerSample = BitConverter.ToInt16(buffer, 14); // 8 bits = 8, 16 bits = 16, etc.
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// data
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buffer = new byte[8];
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stream.Position = ConstantHeaderSize + FmtChunkSize;
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stream.Read(buffer, 0, buffer.Length);
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DataId = Encoding.UTF8.GetString(buffer, 0, 4);
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DataChunkSize = BitConverter.ToUInt32(buffer, 4);
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DataStartPosition = ConstantHeaderSize + FmtChunkSize + 8;
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// if some other ChunckId than 'data' (e.g. LIST) we search for 'data'
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long oldPos = ConstantHeaderSize + FmtChunkSize;
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while (DataId != "data" && oldPos + DataChunkSize + 16 < stream.Length)
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{
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oldPos = oldPos + DataChunkSize + 8;
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stream.Position = oldPos;
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stream.Read(buffer, 0, buffer.Length);
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DataId = Encoding.UTF8.GetString(buffer, 0, 4);
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DataChunkSize = BitConverter.ToUInt32(buffer, 4);
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DataStartPosition = (int)oldPos + 8;
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}
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_headerData = new byte[DataStartPosition];
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stream.Position = 0;
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stream.Read(_headerData, 0, _headerData.Length);
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}
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public long BytesPerSecond
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{
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get
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{
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return (long)SampleRate * (BitsPerSample / 8) * NumberOfChannels;
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}
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}
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public double LengthInSeconds
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{
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get
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{
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return (double)DataChunkSize / BytesPerSecond;
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}
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}
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internal void WriteHeader(Stream toStream, int sampleRate, int numberOfChannels, int bitsPerSample, int dataSize)
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{
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const int fmtChunckSize = 16;
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const int headerSize = 44;
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int byteRate = sampleRate * (bitsPerSample / 8) * numberOfChannels;
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WriteInt32ToByteArray(_headerData, 4, dataSize + headerSize - 8);
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WriteInt16ToByteArray(_headerData, 16, fmtChunckSize); //
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WriteInt16ToByteArray(_headerData, ConstantHeaderSize + 2, numberOfChannels);
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WriteInt32ToByteArray(_headerData, ConstantHeaderSize + 4, sampleRate);
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WriteInt32ToByteArray(_headerData, ConstantHeaderSize + 8, byteRate);
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WriteInt16ToByteArray(_headerData, ConstantHeaderSize + 14, bitsPerSample);
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_headerData[ConstantHeaderSize + fmtChunckSize + 0] = Convert.ToByte('d');
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_headerData[ConstantHeaderSize + fmtChunckSize + 1] = Convert.ToByte('a');
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_headerData[ConstantHeaderSize + fmtChunckSize + 2] = Convert.ToByte('t');
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_headerData[ConstantHeaderSize + fmtChunckSize + 3] = Convert.ToByte('a');
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WriteInt32ToByteArray(_headerData, ConstantHeaderSize + fmtChunckSize + 4, dataSize);
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toStream.Write(_headerData, 0, headerSize);
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}
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private static void WriteInt16ToByteArray(byte[] headerData, int index, int value)
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{
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byte[] buffer = BitConverter.GetBytes((short)value);
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for (int i = 0; i < buffer.Length; i++)
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headerData[index + i] = buffer[i];
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}
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private static void WriteInt32ToByteArray(byte[] headerData, int index, int value)
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{
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byte[] buffer = BitConverter.GetBytes(value);
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for (int i = 0; i < buffer.Length; i++)
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headerData[index + i] = buffer[i];
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}
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}
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public class WavePeakGenerator
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{
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private Stream _stream;
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private byte[] _data;
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private delegate int ReadSampleDataValueDelegate(ref int index);
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public WaveHeader Header { get; private set; }
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/// <summary>
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/// Lowest data value
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/// </summary>
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public int DataMinValue { get; private set; }
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/// <summary>
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/// Highest data value
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/// </summary>
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public int DataMaxValue { get; private set; }
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/// <summary>
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/// Number of peaks per second (should be divideable by SampleRate)
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/// </summary>
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public int PeaksPerSecond { get; private set; }
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/// <summary>
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/// List of all peak samples (channels are merged)
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/// </summary>
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public List<int> PeakSamples { get; private set; }
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/// <summary>
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/// List of all samples (channels are merged)
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/// </summary>
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public List<int> AllSamples { get; private set; }
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/// <summary>
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/// Constructor
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/// </summary>
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/// <param name="fileName">Wave file name</param>
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public WavePeakGenerator(string fileName)
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{
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Initialize(new FileStream(fileName, FileMode.Open, FileAccess.Read));
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}
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/// <summary>
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/// Constructor
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/// </summary>
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/// <param name="stream">Stream of a wave file</param>
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public WavePeakGenerator(Stream stream)
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{
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Initialize(stream);
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}
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/// <summary>
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/// Generate peaks (samples with some interval) for an uncompressed wave file
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/// </summary>
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/// <param name="peaksPerSecond">Sampeles per second / sample rate</param>
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/// <param name="delayInMilliseconds">Delay in milliseconds (normally zero)</param>
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public void GeneratePeakSamples(int peaksPerSecond, int delayInMilliseconds)
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{
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PeaksPerSecond = peaksPerSecond;
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ReadSampleDataValueDelegate readSampleDataValue = GetSampleDataRerader();
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DataMinValue = int.MaxValue;
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DataMaxValue = int.MinValue;
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PeakSamples = new List<int>();
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if (delayInMilliseconds > 0)
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{
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for (int i = 0; i < peaksPerSecond * delayInMilliseconds / 1000; i++)
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PeakSamples.Add(0);
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}
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int bytesInterval = (int)Header.BytesPerSecond / PeaksPerSecond;
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_data = new byte[Header.BytesPerSecond];
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_stream.Position = Header.DataStartPosition;
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int bytesRead = _stream.Read(_data, 0, _data.Length);
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while (bytesRead == Header.BytesPerSecond)
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{
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for (int i = 0; i < Header.BytesPerSecond; i += bytesInterval)
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{
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int index = i;
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int value = 0;
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for (int channelNumber = 0; channelNumber < Header.NumberOfChannels; channelNumber++)
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{
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value += readSampleDataValue.Invoke(ref index);
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}
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value = value / Header.NumberOfChannels;
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if (value < DataMinValue)
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DataMinValue = value;
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if (value > DataMaxValue)
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DataMaxValue = value;
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PeakSamples.Add(value);
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}
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bytesRead = _stream.Read(_data, 0, _data.Length);
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}
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}
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public void GenerateAllSamples()
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{
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// determine how to read sample values
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ReadSampleDataValueDelegate readSampleDataValue = GetSampleDataRerader();
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// load data
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_data = new byte[Header.DataChunkSize];
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_stream.Position = Header.DataStartPosition;
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_stream.Read(_data, 0, _data.Length);
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// read sample values
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DataMinValue = int.MaxValue;
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DataMaxValue = int.MinValue;
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AllSamples = new List<int>();
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int index = 0;
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while (index + Header.NumberOfChannels < Header.DataChunkSize)
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{
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int value = 0;
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for (int channelNumber = 0; channelNumber < Header.NumberOfChannels; channelNumber++)
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{
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value += readSampleDataValue.Invoke(ref index);
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}
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value = value / Header.NumberOfChannels;
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if (value < DataMinValue)
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DataMinValue = value;
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if (value > DataMaxValue)
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DataMaxValue = value;
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AllSamples.Add(value);
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}
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}
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public void WritePeakSamples(string fileName)
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{
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using (var fs = new FileStream(fileName, FileMode.Create, FileAccess.Write))
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{
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WritePeakSamples(fs);
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}
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}
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public void WritePeakSamples(Stream stream)
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{
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Header.WriteHeader(stream, PeaksPerSecond, 1, 16, PeakSamples.Count * 2);
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WritePeakData(stream);
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stream.Flush();
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}
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private void WritePeakData(Stream stream)
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{
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foreach (var value in PeakSamples)
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{
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byte[] buffer = BitConverter.GetBytes((short)(value));
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stream.Write(buffer, 0, buffer.Length);
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}
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}
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private void Initialize(Stream stream)
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{
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_stream = stream;
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Header = new WaveHeader(_stream);
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}
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private int ReadValue8Bit(ref int index)
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{
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int result = _data[index];
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index += 2;
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return result;
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}
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private int ReadValue16Bit(ref int index)
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{
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int result = BitConverter.ToInt16(_data, index);
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index += 2;
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return result;
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}
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private int ReadValue24Bit(ref int index)
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{
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var buffer = new byte[4];
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buffer[0] = 0;
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buffer[1] = _data[index];
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buffer[2] = _data[index + 1];
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buffer[3] = _data[index + 2];
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int result = BitConverter.ToInt32(buffer, 0);
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index += 3;
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return result;
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}
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private int ReadValue32Bit(ref int index)
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{
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int result = BitConverter.ToInt32(_data, index);
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index += 4;
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return result;
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}
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/// <summary>
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/// Determine how to read sample values
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/// </summary>
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/// <returns>Sample data reader that matches bits per sample</returns>
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private ReadSampleDataValueDelegate GetSampleDataRerader()
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{
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ReadSampleDataValueDelegate readSampleDataValue;
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switch (Header.BitsPerSample)
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{
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case 8:
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readSampleDataValue = ReadValue8Bit;
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break;
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case 16:
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readSampleDataValue = ReadValue16Bit;
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break;
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case 24:
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readSampleDataValue = ReadValue24Bit;
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break;
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case 32:
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readSampleDataValue = ReadValue32Bit;
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break;
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default:
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throw new InvalidDataException("Cannot read bits per sample of " + Header.BitsPerSample);
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}
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return readSampleDataValue;
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}
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public void Dispose()
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{
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Close();
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}
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public void Close()
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{
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if (_stream != null)
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_stream.Close();
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}
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//////////////////////////////////////// SPECTRUM ///////////////////////////////////////////////////////////
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public List<Bitmap> GenerateFourierData(int nfft, string spectrogramDirectory, int delayInMilliseconds)
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{
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const int bitmapWidth = 1024;
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var bitmaps = new List<Bitmap>();
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// setup fourier transformation
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var f = new Fourier(nfft, true);
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double divider = 2.0;
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for (int k = 0; k < Header.BitsPerSample - 2; k++)
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divider *= 2;
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// determine how to read sample values
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ReadSampleDataValueDelegate readSampleDataValue = GetSampleDataRerader();
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// set up one column of the spectrogram
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var palette = new Color[nfft];
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if (Configuration.Settings.VideoControls.SpectrogramAppearance == "Classic")
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{
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for (int colorIndex = 0; colorIndex < nfft; colorIndex++)
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palette[colorIndex] = PaletteValue(colorIndex, nfft);
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}
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else
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{
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var list = SmoothColors(0, 0, 0, Configuration.Settings.VideoControls.WaveformColor.R,
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Configuration.Settings.VideoControls.WaveformColor.G,
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Configuration.Settings.VideoControls.WaveformColor.B, nfft);
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for (int i = 0; i < nfft; i++)
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palette[i] = list[i];
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}
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// read sample values
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DataMinValue = int.MaxValue;
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DataMaxValue = int.MinValue;
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var samples = new List<int>();
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int index = 0;
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int sampleSize = nfft * bitmapWidth;
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int count = 0;
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long totalSamples = 0;
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// write delay (if any)
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int delaySampleCount = (int)(Header.SampleRate * (delayInMilliseconds / TimeCode.BaseUnit));
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for (int i = 0; i < delaySampleCount; i++)
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{
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samples.Add(0);
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if (samples.Count == sampleSize)
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{
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var samplesAsReal = new double[sampleSize];
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for (int k = 0; k < sampleSize; k++)
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samplesAsReal[k] = 0;
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var bmp = DrawSpectrogram(nfft, samplesAsReal, f, palette);
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bmp.Save(Path.Combine(spectrogramDirectory, count + ".gif"), System.Drawing.Imaging.ImageFormat.Gif);
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bitmaps.Add(bmp);
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samples = new List<int>();
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count++;
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}
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}
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// load data in smaller parts
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_data = new byte[Header.BytesPerSecond];
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_stream.Position = Header.DataStartPosition;
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int bytesRead = _stream.Read(_data, 0, _data.Length);
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while (bytesRead == Header.BytesPerSecond)
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{
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while (index < Header.BytesPerSecond)
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{
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int value = 0;
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for (int channelNumber = 0; channelNumber < Header.NumberOfChannels; channelNumber++)
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{
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value += readSampleDataValue.Invoke(ref index);
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}
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value = value / Header.NumberOfChannels;
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if (value < DataMinValue)
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DataMinValue = value;
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if (value > DataMaxValue)
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DataMaxValue = value;
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samples.Add(value);
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totalSamples++;
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if (samples.Count == sampleSize)
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{
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var samplesAsReal = new double[sampleSize];
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for (int k = 0; k < sampleSize; k++)
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samplesAsReal[k] = samples[k] / divider;
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var bmp = DrawSpectrogram(nfft, samplesAsReal, f, palette);
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bmp.Save(Path.Combine(spectrogramDirectory, count + ".gif"), System.Drawing.Imaging.ImageFormat.Gif);
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bitmaps.Add(bmp);
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samples = new List<int>();
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count++;
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}
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}
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bytesRead = _stream.Read(_data, 0, _data.Length);
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index = 0;
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}
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if (samples.Count > 0)
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{
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var samplesAsReal = new double[sampleSize];
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for (int k = 0; k < sampleSize && k < samples.Count; k++)
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samplesAsReal[k] = samples[k] / divider;
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var bmp = DrawSpectrogram(nfft, samplesAsReal, f, palette);
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bmp.Save(Path.Combine(spectrogramDirectory, count + ".gif"), System.Drawing.Imaging.ImageFormat.Gif);
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bitmaps.Add(bmp);
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}
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var doc = new XmlDocument();
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doc.LoadXml("<SpectrogramInfo><SampleDuration/><TotalDuration/><AudioFormat /><AudioFormat /><ChunkId /><SecondsPerImage /><ImageWidth /><NFFT /></SpectrogramInfo>");
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double sampleDuration = Header.LengthInSeconds / (totalSamples / Convert.ToDouble(nfft));
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doc.DocumentElement.SelectSingleNode("SampleDuration").InnerText = sampleDuration.ToString(CultureInfo.InvariantCulture);
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doc.DocumentElement.SelectSingleNode("TotalDuration").InnerText = Header.LengthInSeconds.ToString(CultureInfo.InvariantCulture);
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doc.DocumentElement.SelectSingleNode("AudioFormat").InnerText = Header.AudioFormat.ToString(CultureInfo.InvariantCulture);
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doc.DocumentElement.SelectSingleNode("ChunkId").InnerText = Header.ChunkId.ToString(CultureInfo.InvariantCulture);
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doc.DocumentElement.SelectSingleNode("SecondsPerImage").InnerText = ((double)(sampleSize / (double)Header.SampleRate)).ToString(CultureInfo.InvariantCulture);
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doc.DocumentElement.SelectSingleNode("ImageWidth").InnerText = bitmapWidth.ToString(CultureInfo.InvariantCulture);
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doc.DocumentElement.SelectSingleNode("NFFT").InnerText = nfft.ToString(CultureInfo.InvariantCulture);
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doc.Save(Path.Combine(spectrogramDirectory, "Info.xml"));
|
|
|
|
return bitmaps;
|
|
}
|
|
|
|
private static Bitmap DrawSpectrogram(int nfft, double[] samples, Fourier f, Color[] palette)
|
|
{
|
|
const int overlap = 0;
|
|
int numSamples = samples.Length;
|
|
int colIncrement = nfft * (1 - overlap);
|
|
|
|
int numcols = numSamples / colIncrement;
|
|
// make sure we don't step beyond the end of the recording
|
|
while ((numcols - 1) * colIncrement + nfft > numSamples)
|
|
numcols--;
|
|
|
|
double[] real = new double[nfft];
|
|
double[] imag = new double[nfft];
|
|
double[] magnitude = new double[nfft / 2];
|
|
var bmp = new Bitmap(numcols, nfft / 2);
|
|
for (int col = 0; col <= numcols - 1; col++)
|
|
{
|
|
// read a segment of the recorded signal
|
|
for (int c = 0; c <= nfft - 1; c++)
|
|
{
|
|
imag[c] = 0;
|
|
real[c] = samples[col * colIncrement + c] * Fourier.Hanning(nfft, c);
|
|
}
|
|
|
|
// transform to the frequency domain
|
|
f.FourierTransform(real, imag);
|
|
|
|
// and compute the magnitude spectrum
|
|
f.MagnitudeSpectrum(real, imag, Fourier.W0Hanning, magnitude);
|
|
|
|
// Draw
|
|
for (int newY = 0; newY < nfft / 2 - 1; newY++)
|
|
{
|
|
int colorIndex = MapToPixelIndex(magnitude[newY], 100, 255);
|
|
bmp.SetPixel(col, (nfft / 2 - 1) - newY, palette[colorIndex]);
|
|
}
|
|
}
|
|
return bmp;
|
|
}
|
|
|
|
public static Color PaletteValue(int x, int range)
|
|
{
|
|
double g;
|
|
double r;
|
|
double b;
|
|
|
|
double r4 = range / 4.0;
|
|
const double u = 255;
|
|
|
|
if (x < r4)
|
|
{
|
|
b = x / r4;
|
|
g = 0;
|
|
r = 0;
|
|
}
|
|
else if (x < 2 * r4)
|
|
{
|
|
b = (1 - (x - r4) / r4);
|
|
g = 1 - b;
|
|
r = 0;
|
|
}
|
|
else if (x < 3 * r4)
|
|
{
|
|
b = 0;
|
|
g = (2 - (x - r4) / r4);
|
|
r = 1 - g;
|
|
}
|
|
else
|
|
{
|
|
b = (x - 3 * r4) / r4;
|
|
g = 0;
|
|
r = 1 - b;
|
|
}
|
|
|
|
r = ((int)(Math.Sqrt(r) * u)) & 0xff;
|
|
g = ((int)(Math.Sqrt(g) * u)) & 0xff;
|
|
b = ((int)(Math.Sqrt(b) * u)) & 0xff;
|
|
|
|
return Color.FromArgb((int)r, (int)g, (int)b);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Maps magnitudes in the range [-rangedB .. 0] dB to palette index values in the range [0 .. rangeIndex-1]
|
|
/// and computes and returns the index value which corresponds to passed-in magnitude
|
|
/// </summary>
|
|
private static int MapToPixelIndex(double magnitude, double rangedB, int rangeIndex)
|
|
{
|
|
const double log10 = 2.30258509299405;
|
|
|
|
if (magnitude == 0)
|
|
return 0;
|
|
|
|
double levelIndB = 20 * Math.Log(magnitude) / log10;
|
|
if (levelIndB < -rangedB)
|
|
return 0;
|
|
|
|
return (int)(rangeIndex * (levelIndB + rangedB) / rangedB);
|
|
}
|
|
|
|
private static List<Color> SmoothColors(int fromR, int fromG, int fromB, int toR, int toG, int toB, int count)
|
|
{
|
|
while (toR < 255 && toG < 255 && toB < 255)
|
|
{
|
|
toR++;
|
|
toG++;
|
|
toB++;
|
|
}
|
|
|
|
var list = new List<Color>();
|
|
double r = fromR;
|
|
double g = fromG;
|
|
double b = fromB;
|
|
double diffR = (toR - fromR) / (double)count;
|
|
double diffG = (toG - fromG) / (double)count;
|
|
double diffB = (toB - fromB) / (double)count;
|
|
|
|
for (int i = 0; i < count; i++)
|
|
{
|
|
list.Add(Color.FromArgb((int)r, (int)g, (int)b));
|
|
r += diffR;
|
|
g += diffG;
|
|
b += diffB;
|
|
}
|
|
return list;
|
|
}
|
|
|
|
}
|
|
} |