//this is a simple function to copy each motion vector into a structured array
//simplifies indexing when reconstructing the pixels
private void copyMVs(MVPair[,] MVArray)
{
for (int i = 0; i < MVArray.GetLength(0); i++)
{
for (int j = 0; j < MVArray.GetLength(1); j++)
{
int mvX = byteArray[index++];
int mvY = byteArray[index++];
if (mvX > 127)
{
mvX -= 256;
}
if (mvY > 127)
{
mvY -= 256;
}
//Debug.Write("(" + mvX + ", " + mvY + ") " + Environment.NewLine);
MVArray[i, j] = new MVPair(mvX, mvY);
}
}
}
//this is the entire decompression routine function.
public void daDecomp()
{
//open the file!
byteArray = File.ReadAllBytes("thefile.cam");
//read width and height
width = BitConverter.ToInt32(byteArray, 0);
height = BitConverter.ToInt32(byteArray, 4);
int width2 = (int)Math.Ceiling(width / 2.0);
int height2 = (int)Math.Ceiling(height / 2.0);
//read the first frame channels
int yCount = BitConverter.ToInt32(byteArray, 8);
int CbCount = BitConverter.ToInt32(byteArray, 12);
int CrCount = BitConverter.ToInt32(byteArray, 16);
//read the 2nd frame channels
int diffYCount = BitConverter.ToInt32(byteArray, 20);
int diffCbCount = BitConverter.ToInt32(byteArray, 24);
int diffCrCount = BitConverter.ToInt32(byteArray, 28);
//intialize the Y Cb Cr for class!
Y = new double[width, height];
Cb = new double[width, height];
Cr = new double[width, height];
//rewrite array w/o counts, makes indexing SIMPLE!
Array.Copy(byteArray, 32, byteArray, 0, byteArray.Length - 32);
//decode the Y Cb Cr lists into their channel arrays
DecodeChannel(Y, 0, yCount, width, height, luminance);
DecodeChannel(Cb, yCount, yCount + CbCount, width2, height2, chrominance);
DecodeChannel(Cr, yCount + CbCount, yCount + CbCount + CrCount, width2, height2, chrominance);
//initialize the difference Y Cb Cr!
double[,] diffY = new double[width, height];
double[,] diffCb = new double[width, height];
double[,] diffCr = new double[width, height];
//decode the Y Cb Cr difference lists into their channel arrays
int iFrameCount = yCount + CbCount + CrCount;
DecodeChannel(diffY, iFrameCount, iFrameCount + diffYCount, width, height, luminance);
DecodeChannel(diffCb, iFrameCount + diffYCount, iFrameCount + diffYCount + diffCbCount, width2, height2, chrominance);
DecodeChannel(diffCr, iFrameCount + diffYCount + diffCbCount, iFrameCount + diffYCount + diffCbCount + diffCrCount, width2, height2, chrominance);
//INITIALIZE the motion vector structured arrays!
MVPair[,] YMV = new MVPair[(int)Math.Ceiling(width / 8.0), (int)Math.Ceiling(height / 8.0)];
MVPair[,] CbMV = new MVPair[(int)Math.Ceiling(width2 / 8.0), (int)Math.Ceiling(height2 / 8.0)];
MVPair[,] CrMV = new MVPair[(int)Math.Ceiling(width2 / 8.0), (int)Math.Ceiling(height2 / 8.0)];
//rewrite the MVs at the start of the array
int countsAndChannels = iFrameCount + diffYCount + diffCbCount + diffCrCount;
Array.Copy(byteArray, countsAndChannels, byteArray, 0, byteArray.Length - countsAndChannels);
//read the bytes as ints and get the 2's complements back as initial values
copyMVs(YMV);
copyMVs(CbMV);
copyMVs(CrMV);
//build p frame y cb cr channels from differences and motion vectors
implementMotionVectors(YMV, diffY, diffY.GetLength(0), diffY.GetLength(1), Y);
implementMotionVectors(CbMV, diffCb, diffCb.GetLength(0) / 2, diffCb.GetLength(1) / 2, Cb);
implementMotionVectors(CrMV, diffCr, diffCr.GetLength(0) / 2, diffCr.GetLength(1) / 2, Cr);
//supersample iframe cb cr and switch back to rgb and write to the iframe bmp
bmp = new Bitmap(width, height);
supersample();
convertYCbCr2RGB();
//supersample pframe cb cr and switch back to rgb and write to the pframe bmp
bmp2 = new Bitmap(width, height);
double[,] superCb = new double[width, height];
double[,] superCr = new double[width, height];
int sx = 0, sy = 0;
for (int x = 0; x < width; x = x + 2)
{
for (int y = 0; y < height; y = y + 2)
{
superCb[x, y] = diffCb[sx, sy];
if (x < width - 1)
{
superCb[x + 1, y] = diffCb[sx, sy];
}
if (y < height - 1)
{
superCb[x, y + 1] = diffCb[sx, sy];
}
if (x < width - 1 && y < height - 1)
{
superCb[x + 1, y + 1] = diffCb[sx, sy];
}
superCr[x, y] = diffCr[sx, sy];
if (x < width - 1)
{
superCr[x + 1, y] = diffCr[sx, sy];
}
if (y < height - 1)
{
superCr[x, y + 1] = diffCr[sx, sy];
}
if (x < width - 1 && y < height - 1)
{
superCr[x + 1, y + 1] = diffCr[sx, sy];
}
sy++;
}
sx++;
sy = 0;
}
diffCb = superCb;
diffCr = superCr;
for (int x = 0; x < width; x++)
{
for (int y = 0; y < height; y++)
{
double thisY = diffY[x, y];
double ThisCb = diffCb[x, y];
double thisCr = diffCr[x, y];
int r = (int)(1.164 * (thisY - 16) + 1.596 * (thisCr - 128));
int g = (int)(1.164 * (thisY - 16) - 0.813 * (thisCr - 128) - 0.392 * (ThisCb - 128));
int b = (int)(1.164 * (thisY - 16) + 2.017 * (ThisCb - 128));
r = Math.Max(0, Math.Min(255, r));
g = Math.Max(0, Math.Min(255, g));
b = Math.Max(0, Math.Min(255, b));
bmp2.SetPixel(x, y, Color.FromArgb(r, g, b));
}
}
}
