public AccessibleBitmapBytewise(AccessibleBitmap aBitmap)
{
width = aBitmap.width;
height = aBitmap.height;
pixelBytes = aBitmap.pixelBytes;
byteArray = aBitmap.GetRawPixelBytes();
}
// This function is used to compress the image using the LZW algorithm
public static byte[] Compress(AccessibleBitmap source)
{
// Add first 255 standard values to LZWDictionary in LZWCompressor.cs
string[] LZWDictionary = new string[256];
for (int i = 0; i < 256; i++)
{
LZWDictionary[i] = ((char)i).ToString();
}
List <string> dictionary = new List <string>(LZWDictionary); // Clone dictionary of all bytes
Queue <byte> bytes = new Queue <byte>(source.GetRawPixelBytes()); // Get all bytes from the source image
BitStreamFIFO bs = new BitStreamFIFO(); // Create bitstream for output
int maxDictSize = (int)Math.Pow(2, maxBitCount); // Get maximum dictionary size
string encodingString = ((char)bytes.Dequeue()).ToString(); // Create string to add encoding to
while (bytes.Count > 0)
{
// Clear dict if full
if (dictionary.Count >= maxDictSize)
{
dictionary = new List <string>(LZWDictionary);
}
char b = (char)bytes.Dequeue();
if (dictionary.Contains(encodingString + b))
{
encodingString += b;
}
else
{
bs.Write(dictionary.FindIndex(x => x.StartsWith(encodingString)), maxBitCount);
dictionary.Add(encodingString + b);
encodingString = b.ToString();
}
}
// Write remaining byte to bitstream
bs.Write(dictionary.FindIndex(x => x.StartsWith(encodingString)), maxBitCount);
// Return the bitstream as byte array
return(bs.ToByteArray());
}
//Compress aBitmap into byte array
public static byte[] Compress(AccessibleBitmap source)
{
return(VaryingIntArrayCompressor.Compress(Array.ConvertAll(source.GetRawPixelBytes(), Convert.ToInt32)).ToByteArray());
}
//Compress aBitmap into byte array
public static byte[] Compress(AccessibleBitmap source)
{
//Return raw aBitmap
return(source.GetRawPixelBytes());
}