public static void WriteBlock(
BitStream jpegStream,
DCEncode dcValue,
List <ACEncode> acValues,
HuffmanTree dcTree,
HuffmanTree acTree
)
{
// encode dc value of block
{
//write huffman encoded category into bit stream
dcTree.EncodeInt(dcValue.Category, jpegStream);
// write bit pattern for value, provide category for length
if (dcValue.Category != 0)
{
jpegStream.writeBits(dcValue.BitPattern, dcValue.Category);
}
}
// encode ac values of block
acValues.ForEach(acValue =>
{
acTree.EncodeInt(acValue.Flag, jpegStream);
if (acValue.Category != 0)
{
jpegStream.writeBits(acValue.BitPattern, acValue.Category);
}
});
}
public static (DCEncode[], List <ACEncode>[]) ChannelToArrayY(List <DCEncode> dcValues, List <List <ACEncode> > acValues, int length)
{
DCEncode[] dcArray = dcValues.ToArray();
List <ACEncode>[] acArray = acValues.ToArray();
int amountBlocks = dcArray.Length; // dc length = ac length
DCEncode[] dcResult = new DCEncode[amountBlocks];
List <ACEncode>[] acResult = new List <ACEncode> [amountBlocks];
int index = 0;
for (int i = 0; i < amountBlocks; i += 2)
{
if (((i / length) % 2) != 0)
{
i += length - 2;
continue;
}
// [0] + [1] + [0 + length] + [1 + length]
dcResult[index] = dcArray[i];
acResult[index] = acArray[i];
index++;
dcResult[index] = dcArray[i + 1];
acResult[index] = acArray[i + 1];
index++;
dcResult[index] = dcArray[i + length];
acResult[index] = acArray[i + length];
index++;
dcResult[index] = dcArray[i + 1 + length];
acResult[index] = acArray[i + 1 + length];
index++;
}
return(dcArray, acArray);
}