//test the number passed into this method against the image. Returns true if the number of bits tested returns a valid message header
private char Decode(int numBitsUse, EmbedTracker tracker)
{
Byte r, g, b;
int numRead = 0;
BitArray dataByte = new BitArray(8);
try
{
//try and read for the first character of the start of message which should be at the beginning of the image
while (numRead < 8)
{
int processingX = tracker.currX;
int processingY = tracker.currY;
var currPixel = orgBitmap.GetPixel(processingX, processingY);
BitArray currentByte = new BitArray(8);
switch (tracker.nxtColorVal)
{
case 0:
currentByte = new BitArray(new byte[] { currPixel.R });
break;
case 1:
currentByte = new BitArray(new byte[] { currPixel.G });
break;
case 2:
currentByte = new BitArray(new byte[] { currPixel.B });
break;
}
//this is not correct might be an encoding issue
for (int i = 0; i < numBitsUse; i++)
{
if (numRead < 8)
{
dataByte[numRead] = currentByte[i];
numRead++;
}
else
{
break;
}
}
tracker.incrementNextTarget();
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
return((char)ConvertToByte(dataByte));
}
//store the information in the source array into the target array
private void store(BitArray targetArray, BitArray sourceArray, EmbedTracker tracker, int numUsed)
{
//if they select 3 bits to use
//on the last pass -- would only need to use 2 bits ( 3, 6, 9)
int numToUse = numBitsUse;
try
{
if ((numUsed + numToUse) > 8)
{
numToUse = ((numToUse + numUsed) % 8) + 1;
}
for (int j = 0; j < numToUse; j++)
{
targetArray[j] = sourceArray[numUsed];
tracker.incrementNextTarget();
numUsed++;
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
