public static double[][] ReadBMPGrayscale(string filePath)
{
double[][] image;
var bmpfile = new BinaryFile(filePath);
// "BM" format tag check
if (!"BM".Equals(bmpfile.ReadString(2)))
{
Console.Error.WriteLine("This file is not in BMP format");
return(null);
}
bmpfile.Seek(8, SeekOrigin.Current); // skipping useless tags
int offset = (int)bmpfile.ReadUInt32() - 54; // header offset
bmpfile.Seek(4, SeekOrigin.Current); // skipping useless tags
int x = (int)bmpfile.ReadUInt32();
int y = (int)bmpfile.ReadUInt32();
bmpfile.Seek(2, SeekOrigin.Current); // skipping useless tags
int bitDepth = bmpfile.ReadUInt16();
int numBytes = bitDepth / 8;
bmpfile.Seek(24 + offset, SeekOrigin.Current); // skipping useless tags
// image allocation
image = new double[y][];
// initialise jagged array
for (int iy = 0; iy < y; iy++)
{
image[iy] = new double[x];
}
// calculate zero bytes (bytes to skip at the end of each bitmap line)
int zerobytes = (byte)(4 - ((x * numBytes) & numBytes));
if (zerobytes == 4)
{
zerobytes = 0;
}
// backwards reading
for (int iy = y - 1; iy != -1; iy--)
{
for (int ix = 0; ix < x; ix++)
{
for (int ic = numBytes - 1; ic != -1; ic--)
{
int val = bmpfile.ReadByte();
if (ic == 0 && numBytes == 4)
{
// if reading 32 bit, ignore the alpha bit
}
else
{
// Conversion to grey by averaging the three channels
image[iy][ix] += (double)val * (1.0 / (255.0 * 3.0));
}
}
}
bmpfile.Seek(zerobytes, SeekOrigin.Current); // skipping padding bytes
}
bmpfile.Close();
return(image);
}
/**
* Reads file header into the struct.
*
* @param fs input file stream
* @see WaveFile::hdr
*/
private void LoadHeader(ref BinaryFile fs)
{
hdr.RIFF = fs.ReadString(4);
hdr.DataLength = fs.ReadUInt32();
hdr.WAVE = fs.ReadString(4);
hdr.fmt_ = fs.ReadString(4);
hdr.SubBlockLength = fs.ReadUInt32();
hdr.formatTag = fs.ReadUInt16();
hdr.Channels = fs.ReadUInt16();
hdr.SampFreq = fs.ReadUInt32();
hdr.BytesPerSec = fs.ReadUInt32();
hdr.BytesPerSamp = fs.ReadUInt16();
hdr.BitsPerSamp = fs.ReadUInt16();
hdr.data = fs.ReadString(4);
hdr.WaveSize = fs.ReadUInt32();
}
public bool Read(string filePath)
{
if (File.Exists(filePath)) {
string fileName = Path.GetFileNameWithoutExtension(filePath);
PresetName = fileName;
BinaryFile bFile = new BinaryFile(filePath, BinaryFile.ByteOrder.BigEndian);
string firstChunkID = bFile.ReadString(4); // chunk ID = "FORM"
int ckSize = bFile.ReadInt32();
string formType = bFile.ReadString(4);
// read first data chunk
string chunkID = bFile.ReadString(4);
// if chunkID == "COMT" then CommentsChunk
if (chunkID.Equals("COMT")) {
long curposTmpComt = bFile.GetPosition();
bFile.Seek(curposTmpComt-4);
// CommentsChunk
string chunkIDComt = bFile.ReadString(4); // chunk ID = "COMT"
int chunkSizeComt = bFile.ReadInt32();
int numComments = bFile.ReadUInt16();
long curposTmpComt2 = bFile.GetPosition();
//comments = bFile.ReadString(chunkSizeComt-2);
for (int i = 0; i < numComments; i++) {
int commentTimestamp = (int) bFile.ReadUInt32();
string marker = bFile.ReadString(4);
int count = (int) bFile.ReadByte();
comments.Add(bFile.ReadString(count));
}
bFile.Seek(curposTmpComt2+chunkSizeComt-2);
}
string chunkID2 = bFile.ReadString(4);
// if chunkID2 == "COMM" then CommonChunk
if (chunkID2.Equals("COMM")) {
long curposTmpComm = bFile.GetPosition();
bFile.Seek(curposTmpComm-4);
// CommonChunk
string chunkIDComm = bFile.ReadString(4); // chunk ID = "COMM"
int chunkSizeComm = bFile.ReadInt32();
channels = bFile.ReadInt16();
numSampleFrames = (int) bFile.ReadUInt32();
bitsPerSample = bFile.ReadInt16();
// read IEEE 80-bit extended double precision
byte[] sampleRateBytes = bFile.ReadBytes(0, 10, BinaryFile.ByteOrder.LittleEndian);
double sampleRateDouble = NAudio.Utils.IEEE.ConvertFromIeeeExtended(sampleRateBytes);
sampleRate = (int) sampleRateDouble;
}
string chunkID3 = bFile.ReadString(4);
// if chunkID3 == "SSND" then SoundDataChunk
if (chunkID3.Equals("SSND")) {
long curposTmpSsnd = bFile.GetPosition();
bFile.Seek(curposTmpSsnd-4);
// SoundDataChunk
string chunkIDSsnd = bFile.ReadString(4); // chunk ID = "SSND"
int chunkSizeSsnd = bFile.ReadInt32();
int offset = (int) bFile.ReadUInt32();
int blocksize = (int) bFile.ReadUInt32();
byte[] data = bFile.ReadBytes(offset, chunkSizeSsnd-8, BinaryFile.ByteOrder.LittleEndian);
// swap waveform data
WaveformData = SwapAiffEndian(data);
}
bFile.Close();
return true;
} else {
return false;
}
}
// read from file a 16-bit integer in little endian
public static UInt16 ReadUInt16(BinaryFile file)
{
return file.ReadUInt16();
}