Image Manager/CVBpy/ImagePixelAccess

This example program is located in your CVB installation under %CVB%Tutorial/Image Manager/CVBpy/ImagePixelAccess.

image_pixel_access.py:

# @brief Example for accessing image pixel values.
 
# CVBpy Example Script
#
# 1. Loads an image from file.
# 2. Converts it to a numpy array without copying
# 3. Modify pixel values through numpy
# 4. Save the image. 
#
# Requires: numpy
 
import os
import cvb
 
image = cvb.Image(os.path.join(cvb.install_path(), "tutorial", "Clara.bmp"))
 
# copy=Fasle is default, but just a request
np_array = cvb.as_array(image, copy=False)
 
if np_array.flags["OWNDATA"]:
    raise RuntimeError("cannot map to numpy array")
 
# pixel access
print("Modifying pixel data via numpy array.")
np_array[83 : 108, 48 : 157] = 0
 
print("Saving: ./ClaraUnknown.bmp")
image.save("ClaraUnknown.bmp")