void LoopTree(bool[] currentTree, int index)
{
int[] node = treeints[index];
if (node[1] == -1)
{
if (currentTree.Length == 0)
{
currentTree = new bool[] { false };
}
//Console.Write("0 " + sortednumbers[node[2]] + " ");
outputStream.Write(false);
outputStream.Write(sortednumbers[node[2]], minBits);
numberVals[node[2]] = currentTree.ToArray();
}
else
{
//Console.Write("1");
outputStream.Write(true);
bool[] passTree = new bool[currentTree.Length + 1];
if (currentTree.Length > 0)
{
Array.Copy(currentTree, passTree, currentTree.Length);
}
passTree[passTree.Length - 1] = true;
LoopTree(passTree, node[2]);
passTree[passTree.Length - 1] = false;
LoopTree(passTree, node[1]);
}
}
//Compress integer array into BitStream
public static BitStreamFIFO Compress(int[] source)
{
//Compress the array of integers using all different compression techniques, where possible at the same time
BitStreamFIFO[] compressionTechniques = new BitStreamFIFO[2];
Parallel.For(0, compressionTechniques.Length, (i, state) =>
{
switch (i)
{
//Huffmann: generate a dictionary of all used integer values where more frequent values have a code with less bits
case 0:
compressionTechniques[i] = HuffmanIntArrayCompressor.Compress(source);
break;
//Variable int length: save smaller integers with less bits than bigger integers
case 1:
compressionTechniques[i] = VaryingIntLengthIntArrayCompressor.Compress(source);
break;
//To add a compression technique, add a new case like the existing ones and increase the length of new byte[??][]
}
});
//Choose the smallest compression type
//Initialize
int smallestID = 0; //The ID of the smallest compression type
int smallestSize = int.MaxValue; //The size ofthe smallest compression type: int.MaxValue is assigned to make sure that the first compression to be checked will be smaaller than this value
//Loop trough all saved compression techniques
for (int i = 0; i < compressionTechniques.Length; i++)
{
//If the current technique is smaller than the smallest technique which has been checked
if (compressionTechniques[i].Length < smallestSize)
{
//Mark this technique as smallest
smallestSize = compressionTechniques[i].Length;
smallestID = i;
}
}
//Create a new BitStream to write necessary information for the decompressor
BitStreamFIFO compressionInfo = new BitStreamFIFO();
//Calculate the amount of bits needed to save the total length in bits of the compressed data
int lengthSaveLength = (int)Math.Ceiling(Math.Log(smallestSize, 2) / 8);
//Write data to the compression info
compressionInfo.Write(smallestID, 2); //The compression technique used
compressionInfo.Write(lengthSaveLength, 6); //The amount of bits needed to save the total length in bits of the compressed data
compressionInfo.Write(smallestSize, lengthSaveLength * 8); //The total length in bits of the compressed data
//Merge the info about the compression type with the compressed data & return
return(BitStreamFIFO.Merge(compressionInfo, compressionTechniques[smallestID]));
}
public TreeWalker(int[] sortedNumbers, int[][] treeInts)
{
sortednumbers = sortedNumbers;
treeints = treeInts;
numberVals = new bool[sortedNumbers.Length][];
minBits = (int)Math.Ceiling(Math.Log(sortedNumbers.Max() + 1, 2));
minBits = minBits < 1 ? 1 : minBits;
outputStream = new BitStreamFIFO();
outputStream.Write((byte)minBits);
outputStream.Write(sortedNumbers.Length - 1, minBits);
//Console.WriteLine(minBits + " " + sortedNumbers.Length);
LoopTree(new bool[0], treeInts.Length - 1);
//Console.WriteLine();
}
// 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 BitStreamFIFO Compress(AccessibleBitmapBitwise source, int bitLayer)
{
//Creates a new BitStreamFIFO object where all bits will be written to
BitStreamFIFO bitStream = new BitStreamFIFO();
//Loop trough all lines of pixels
for (int y = 0; y < source.height; y++)
{
//Loop trough all pixels in this line
for (int x = 0; x < source.width; x++)
{
//Write the bit of this channel from the current pixel to the output BitStream
bitStream.Write(source.GetPixelBit(x, y, bitLayer));
}
}
//Return the BitStream
return(bitStream);
}
//Compress aBitmap into byte array
public static BitStreamFIFO Compress(AccessibleBitmapBitwise source, int bitLayer)
{
//Initialize vars
BitStreamFIFO bitStream = new BitStreamFIFO();
List <int> distances = new List <int>();
int tempDistance = -1;
bool lastVal = source.GetPixelBit(0, 0, bitLayer);
//Iterate trough pixels
for (int y = 0; y < source.height; y++)
{
for (int x = 0; x < source.width; x++)
{
//Take value of pixel & compare with previous value
bool currentBool = source.GetPixelBit(x, y, bitLayer);
if (currentBool == lastVal)
{
//Values are the same, so increase current run
tempDistance++;
}
else
{
//Values are not the same, so save the run and create a new one
distances.Add(tempDistance);
lastVal = currentBool;
tempDistance = 0;
}
}
}
//Save the last run becouse this never happens in the loop
distances.Add(tempDistance);
bool initialVal = source.GetPixelBit(0, 0, bitLayer);
bitStream.Write(initialVal);
BitStreamFIFO output = BitStreamFIFO.Merge(bitStream, VaryingIntArrayCompressor.Compress(distances.ToArray()));
return(output);
}
public static BitStreamFIFO Compress(int[] source)
{
List <int> numbers = new List <int>();
List <int> weights = new List <int>();
foreach (int b in source)
{
if (numbers.Contains(b))
{
weights[numbers.IndexOf(b)]++;
}
else
{
numbers.Add(b);
weights.Add(1);
}
}
List <int> sortedWeightTmp = weights;
sortedWeightTmp.Sort();
int[] sortedWeightsInts = sortedWeightTmp.ToArray();
int[] sortedNumbers = new int[numbers.Count];
int[] sortedWeights = new int[weights.Count];
for (int i = 0; i < sortedWeightTmp.Count; i++)
{
int oldIndex = weights.IndexOf(sortedWeightsInts[i]);
sortedNumbers[i] = numbers[oldIndex];
sortedWeights[i] = weights[oldIndex];
weights[oldIndex] = 0;
}
/*for (int i = 0; i < sortedNumbers.Length; i++)
* {
* Console.WriteLine(sortedNumbers[i] + "\t" + sortedWeights[i]);
* }
* Console.WriteLine();*/
List <int[]> tree = new List <int[]>();
List <int[]> sources = new List <int[]>();
for (int i = 0; i < sortedWeights.Length; i++)
{
sources.Add(new int[] { sortedWeights[i], -1, i });
}
while (sources.Count > 1)
{
tree.AddRange(sources.GetRange(0, 2));
sources.RemoveRange(0, 2);
sources.Add(new int[] { tree[tree.Count - 1][0] + tree[tree.Count - 2][0], tree.Count - 1, tree.Count - 2 });
sources.Sort((s, t) => s[0] - t[0]);
}
tree.Add(sources[0]);
Array.Reverse(sortedNumbers);
TreeWalker walker = new TreeWalker(sortedNumbers, tree.ToArray());
BitStreamFIFO outputStream = walker.outputStream;
//Console.WriteLine("s" + outputStream.Length);
bool[][] numberVals = walker.numberVals;
/*int length = 0;
* for (int i = 0; i < numberVals.Length; i++)
* {
* Console.WriteLine(i + "\t" + sortedNumbers[i] + "\t" + sortedWeights[i] + "\t" + BoolArrString(numberVals[i]));
* length += sortedWeights[i] * numberVals[i].Length;
* }*/
//Console.WriteLine(source.Length);
//Console.WriteLine(length);
foreach (int i in source)
{
int index = Array.IndexOf(sortedNumbers, i);
outputStream.Write(numberVals[index]);
//Console.WriteLine(BoolArrString(numberVals[index]) + "\t" + i);
//Console.WriteLine(i);
}
//Console.WriteLine(source.Length * 8);
//Console.WriteLine("length"+outputStream.Length);
return(outputStream);
}
public static byte[] CompressVertical(AccessibleBitmap source)
{
byte[] lastpixel = null; // Create variable to store the last pixel
int colorCounter = 1; // Create counter for current color
BitStreamFIFO bs = new BitStreamFIFO(); // Create new bitstream for all the bits
int maxCount = 0; // Create variable to store the max bitcount
Queue<PixelArray> output = new Queue<PixelArray>(); // Create list to store all the pixelvalues in
// Write one bit to the bitstream, so the decompressor knows to decompress vertically
bs.Write(true);
// Iterate through every vertical row
for (int x = 0; x < source.width; x++)
{
// Iterate through every pixel in the vertical row
for (int y = 0; y < source.height; y++)
{
// Check if the variable lastpixel is empty
if (lastpixel == null)
{
// If lastpixel is empty, set last pixel to the first pixel
lastpixel = source.GetPixel(x, y);
}
else
{
// If lastpixel isn't empty, compare last pixel with new pixel
if (lastpixel.SequenceEqual(source.GetPixel(x, y)))
{
// Pixels matched, so increase the counter value
colorCounter++;
}
else
{
// If the pixels don't match, add the counter with the last pixel to the output queue
output.Enqueue(new PixelArray(colorCounter, lastpixel));
// Check if the new countervalue is higher then the last one, if so set maxBitCount to that
if (colorCounter > maxCount)
maxCount = colorCounter;
// Reset the colorCounter and set the last pixel to the new pixel
colorCounter = 1;
lastpixel = source.GetPixel(x, y);
}
}
}
}
// Add the remaining pixel(s) to the bitstream
output.Enqueue(new PixelArray(colorCounter, lastpixel));
// Check if the new countervalue is higher then the last one, if so set maxBitCount to that
if (colorCounter > maxCount)
maxCount = colorCounter;
// Write the maxCount to the bitstream
bs.Write((byte)Math.Ceiling(Math.Log(maxCount, 2)));
// Add all the pixels from the queue to the bitstream
while (output.Count > 0)
{
PixelArray pixel = output.Dequeue();
bs.Write(pixel.Count, (int)Math.Ceiling(Math.Log(maxCount, 2)));
bs.Write(pixel.Pixel);
}
// Return the bitsream as a byte[]
return bs.ToByteArray();
}
//Compress integer array into BitStream
public static BitStreamFIFO Compress(int[] source)
{
//Get the amount of bits needed to store the longest run
int invariableMinBits = (int)Math.Ceiling(Math.Log(source.Max() + 1, 2));
invariableMinBits = invariableMinBits < 1 ? 1 : invariableMinBits;
//Initialize
List <int> nonExisting = new List <int>(); //Create a list to which all values that aren't present in the source array will be added
int minBits = invariableMinBits; //The minimum amount of bits used for variable save bits, related to the list of nonexisting values
//Loop trough all possible values within the range of the source values
for (int i = 0; i < source.Max(); i++)
{
//If a value is not present in the source array
if (!source.Contains(i))
{
//Add current value to the list
nonExisting.Add(i);
//Set the minimum amount of bits to save this value
minBits = (int)Math.Ceiling(Math.Log(i + 1, 2));
minBits = minBits < 1 ? 1 : minBits;
//If the amount of unused values is equal to the difference between invariableMinBits and minBits
if (nonExisting.Count >= invariableMinBits - minBits)
{
//Minbits is now the smallest possible amount of bits in which the source array can be saved variable, so stop checking for more unused values
break;
}
}
}
//Divide the source values in categories with the same minimum amount of bits to be saved in
//Create all categories
int[][] distancesByPower = new int[invariableMinBits][];
//Loop trough all categories
for (int i = 0; i < distancesByPower.Length; i++)
{
//Define the smalles and biggest value of the current category
int minVal = (int)Math.Pow(2, i) - 1;
int maxVal = (int)Math.Pow(2, i + 1);
//Add all values within the specified range to this category
distancesByPower[i] = new List <int>(source).FindAll(x => x < maxVal && x >= minVal).ToArray();
}
//Find out which possible minimum amount of bits used will compress the most
//Initialize
int chosenMinBits = invariableMinBits; //The chosen minimum amount of bits
int smallestSize = int.MaxValue; //The size of the compressed data when using the chosen minimum of bits
//Loop trough all possible minimum amounts of bits
for (int i = 0; i <= invariableMinBits - minBits; i++)
{
//Calculate the length of the current minimum amount of bits
//Initialize
int length = 0; //The total length
int baseBits = invariableMinBits - i; //Define the current minimum amount of bits
//Add the length of all data that will be saved in the minimum amount of bits to the length variable
for (int j = 0; j < baseBits; j++)
{
length += distancesByPower[j].Length * baseBits;
}
//Loop trough all data that needs more bits to be saved than the minimum
for (int j = 0; j < i; j++)
{
//Define the minimum bits for this value
int currentBits = invariableMinBits - j;
//Add the minimum bits of this value + the general minimum bits to the length variable, becouse an extra value should be used to indicate the extra amount of bits
length += distancesByPower[currentBits - 1].Length * (baseBits + currentBits);
}
//If the length of this minimum amount of bits is smaller than the chosen amount of bits
if (length < smallestSize)
{
//Set this smallest amount of bits as the chosen amount of bits
smallestSize = length;
chosenMinBits = baseBits;
}
}
//Create a new BitStream as output
BitStreamFIFO bitStream = new BitStreamFIFO();
//Write necessary info for decompressing to the output stream
bitStream.Write((byte)chosenMinBits); //The chosen default bits to save values
bitStream.Write((byte)(invariableMinBits - chosenMinBits)); //The amount of values that trigger an increase of bits per value
//Write all values that trigger an increase of bits per value
for (int i = 0; i < invariableMinBits - chosenMinBits; i++)
{
bitStream.Write(nonExisting[i], chosenMinBits);
}
//Write all values to the stream
//Loop trough all values
foreach (int i in source)
{
//Get the amount of extra bits needed to save this value
int extraBits = 0;
while (Math.Pow(2, chosenMinBits + extraBits) - 1 < i)
{
extraBits++;
}
//Write trigger value to stream if extra bits are needed
if (extraBits > 0)
{
bitStream.Write(nonExisting[extraBits - 1], chosenMinBits);
}
//Write the value to the stream using the correct amount of bits
bitStream.Write(i, chosenMinBits + extraBits);
}
//Return the compressed data
return(bitStream);
}
//Compress aBitmap into byte array
public static byte[] Compress(AccessibleBitmapBytewise source, int byteLayer)
{
//Loop trough all layers of bits, where possible at the same time
AccessibleBitmapBitwise aBitmap = new AccessibleBitmapBitwise(source);
BitStreamFIFO[] byteLayers = new BitStreamFIFO[8];
Parallel.For(byteLayer * 8, byteLayer * 8 + 8, (z, state) => //for(int z = byteLayer * 8; z < byteLayer * 8 + 8; z++)
{
//Compress image using all different compression techniques, where possible at the same time
BitStreamFIFO[] compressionTechniques = new BitStreamFIFO[4];
Parallel.For(0, compressionTechniques.Length, (i, state2) =>
{
switch (i)
{
//Uncompressed (only used if no compression technique is smaller)
case 0:
compressionTechniques[i] = UncompressedBitmapCompressorBitwise.Compress(aBitmap, z);
break;
//Compress bit channel as an integer array using several techniques, using 8-bit integers
case 1:
compressionTechniques[i] = ByteArrayCompressorBitwise.Compress(aBitmap, z);
break;
//Run length compression: save the length of a sequence of bit values instead of saving them seperately
case 2:
compressionTechniques[i] = RunLengthEncodingCompressorBitwise.Compress(aBitmap, z);
break;
//Run length compression vertical: run length compression, but scan the pixels horizontally, becouse with some images this yields better results
case 3:
compressionTechniques[i] = RunLengthEncodingCompressorVerticalBitwise.Compress(aBitmap, z);
break;
//To add a compression technique, add a new case like the existing ones and increase the length of new byte[??][]
}
});
//Choose the smallest compression type
//Initialize
int smallestID = 0; //The ID of the smallest compression type
int smallestSize = int.MaxValue; //The size ofthe smallest compression type: int.MaxValue is assigned to make sure that the first compression to be checked will be smaaller than this value
//Loop trough all saved compression techniques
for (int i = 0; i < compressionTechniques.Length; i++)
{
//If the current technique is smaller than the smallest technique which has been checked
if (compressionTechniques[i].Length < smallestSize)
{
//Mark this technique as smallest
smallestSize = compressionTechniques[i].Length;
smallestID = i;
}
}
//Merge the number of the compression type of this layer with corresponding bitStream
BitStreamFIFO tmpStream = new BitStreamFIFO();
tmpStream.Write(smallestID, 3); //This 3-bit integer indicates which technique the decompressor should use, and should be before the image data
byteLayers[z % 8] = BitStreamFIFO.Merge(tmpStream, compressionTechniques[smallestID]);
});
//Combine all bitstreams & convert the result to a byte array
byte[] outputStream = BitStreamFIFO.Merge(byteLayers).ToByteArray();
//Return the data of all the bit channels combined
return(outputStream);
}
