Crop Function Jython JES

Question

Hi im trying to make a crop function in Jython Environment For Students heres what i have so far.

I am also trying to figure out how to make the canvas the size that all the new pixels will take up.

Any help

def crop(pic, startX, endX, startY, endY):
    canvas = makeEmptyPicture(500, 800)
    for sourceX in range(startX, endX):
        for sourceY in range(startY, endY):
            color = getColor(getPixel(pic, sourceX, sourceY))
            setColor(getPixel(canvas, startX, startY), color)
            startY = startY + 1
        startX = startX + 1
    show(canvas)

Gauthier Boaglio · Answer 1 · 2013-06-24T00:46:32.340

Try this:

Note : The size of the resulting canvas can be obtained from (endX - startX) x (endY - startY)

def crop(pic, startX, endX, startY, endY):  
    # Check if the cropping bounds are OK with size of the original picture 
    if (endX - startX > 0) and (endY - startY > 0) and \
                         (endX < getWidth(pic)) and (endY < getHeight(pic)):
        # Create a canvas with correct size
        canvas = makeEmptyPicture(endX - startX, endY - startY)
        # Browse the interesting part
        for sourceX in range(startX, endX):
            for sourceY in range(startY, endY):
                color = getColor(getPixel(pic, sourceX, sourceY))
                # Write the pixels, 
                # starting from 0 (=startX(Y)-startX(Y)) to endX(Y)
                setColor(getPixel(canvas, 
                              sourceX - startX, sourceY - startY), color)
        return canvas
    else:
        # Print error when passing wrong bounds
        printNow("Error: bad cropping bounds ! - Expected [0.." + 
            str(getWidth(pic)-1) + "] x [0.." +  str(getHeight(pic)-1) + "]")        
        return None

def main():
  file = pickAFile()
  picture = makePicture(file)
  cropPic = crop(picture, 50, 150, 50, 180)
  if (cropPic):
      show(cropPic)

main()

Giving:

........... enter image description here ...............................................................

Output with wrong parameters:

>>> cropPic = crop(picture, 50, 500, 50, 180)
>>> 
======= Loading Progam =======
Error: bad cropping bounds ! - Expected [0..258] x [0..193]

Crop Function Jython JES

1 Answers1