Divide the image into a grid of equal rectangles, each one the same size and big enough to hold the largest graphic.
In your program, load the image into a hidden bitmap and use a nested For..Next loop to grab the contents of each 'cel' on the grid.
Can't give you the exact code required as it depends on the size of your images, but it would be along the lines of:
ImgCounter=1
For Ny=0 To CelsDown-1
For Ny=0 To CelsAcross-1
Get Image ImgCounter,Ny*GridSize,Nx*GridSize,Ny*GridSize+GridSize,Nx*GridSize+GridSize,1
Inc ImgCounter
Next Ny
Next Nx
Once in separate images, you can delete the bitmap and use them for whatever.
TDK_Man