将每像素2字节的MONO-16位图像转换为MONO-16位，C＃中每像素1字节

Question

I am working in C# and I have a monochromatic camera returning to me two successive images. I want to subtract these images.

The camera is set to MONO-16 with resolution 1980x960.

The camera returns to me a vector of 2457600 elements, because each pixel is represented by two bytes so {1980x960 = 1228800} * 2 bytes / pixel = 2457600 .

The problem is that I have to convert the two 2457600 element vectors to two 1228800 vectors in order to do the subtraction.

So I need to combine two successive elements of the 2457600 into one element so that I end up with a vector of 1228800 elements, where its element have 16bit range (0-65536).

I will probably have to create a loop to iterate 1228800 times and in each iteration take two elements from the 2457600 vector:

  for(int i = 0 ; i < 2457600 ; i = i + 2)
  {
     byte BYTE1 = newGrabResultInternal2.ImageData.Buffer[i];
     byte BYTE2 = newGrabResultInternal2.ImageData.Buffer[i+1];        
     // What to do next to combine the 2 bytes into one???
  }

When I have the two bytes which represent 1 pixel, how do I combine them together to give me an intensity value of 16bit depth (0-65536)?

Also, if you can suggest a different approach it would be helpful.

Answer 1

You can use bit operations for that:

for(int i=0;i<2457600;i=i+2)
{
  byte BYTE1 = newGrabResultInternal2.ImageData.Buffer[i];
  byte BYTE2 = newGrabResultInternal2.ImageData.Buffer[i+1];        

   int pixel = ((int)BYTE1 << 8) | ((int)BYTE2);
 }

This will shift BYTE1 8 bits left and then combine it with BYTE2 .

This will make BYTE1 the higher byte and BYTE2 the lower. If you want it the other way around you need to swap them.