public void Combinations_Test()
{
byte runSizeInput1 = 00000000;
ushort codeWordInput1 = 2; // 10 in base 2
byte lengthInput1 = 8; // 1000 in base 2
byte runSizeInput2 = 1;
ushort codeWordInput2 = 3; // 11 in base 2
byte lengthInput2 = 8; // 1000 in base 2
byte runSizeInput3 = 2;
ushort codeWordInput3 = 4; // 100 in base 2
byte lengthInput3 = 8; // 1000 in base 2
HuffmanElement huffmanTestElement1 = new HuffmanElement(runSizeInput1, codeWordInput1, lengthInput1);
HuffmanElement huffmanTestElement2 = new HuffmanElement(runSizeInput2, codeWordInput2, lengthInput2);
HuffmanElement huffmanTestElement3 = new HuffmanElement(runSizeInput3, codeWordInput3, lengthInput3);
HuffmanTable huffTable1 = new HuffmanTable(huffmanTestElement1, huffmanTestElement2, huffmanTestElement3);
byte[] numberOfCodesOutput = huffTable1.Combinations();
Assert.AreEqual(3, numberOfCodesOutput[7]);
}
private void _writeHuffmanSegment(HuffmanTable huffman, byte id, bool dc) {
_jw.WriteBytes(0xff, 0xc4); //DHT marker
ushort len = (ushort)(huffman.Elements.Count + huffman.Combinations().Length + 3);
_jw.WriteBytes((byte)(len >> 8), (byte)(len & 0xff));
byte combined;
if (!dc) {
combined = (byte)((1 << 4) + id);
} else {
combined = id;
}
_jw.WriteBytes(combined);
_jw.WriteBytes(huffman.Combinations());
HuffmanElement[] allElements = huffman.Elements.Values.OrderBy(x => x.Length).ThenBy(x => x.RunSize).ToArray();
foreach (HuffmanElement huffmanElement in allElements) {
_jw.WriteBytes(huffmanElement.RunSize);
}
}
private void _writeHuffmanSegment(HuffmanTable huffman, byte id, bool dc) {
//DHT marker
_jw.WriteBytes(0xff, 0xc4);
//Size of Huffman table in bytes. Calculated as the number of elements +
//the number of combinations + three bytes. Two of them for the length
//itself and the last is for whether it is a DC or not and the ID.
ushort len = (ushort)(huffman.Elements.Count + huffman.Combinations().Length + 3);
_jw.WriteBytes((byte)(len >> 8), (byte)(len & 0xff));
byte combined;
if (!dc) {
combined = (byte)((1 << 4) + id);
} else {
combined = id;
}
//DC/AC and ID
_jw.WriteBytes(combined);
//The table combinations
_jw.WriteBytes(huffman.Combinations());
//Write the elements
HuffmanElement[] allElements = huffman.Elements.Values.OrderBy(x => x.Length).ThenBy(x => x.RunSize).ToArray();
foreach (HuffmanElement huffmanElement in allElements) {
_jw.WriteBytes(huffmanElement.RunSize);
}
}
