1) Digital image processing involves processing digital images using computer software and algorithms. It includes techniques like image enhancement, restoration, compression, and segmentation.
2) The key stages in digital image processing are image acquisition, enhancement, restoration, morphological processing, segmentation, object recognition, representation and description, compression, and color image processing.
3) Digital image processing has various applications including medical imaging, space exploration, document processing, photography, remote sensing, and video/film special effects. It covers almost the entire electromagnetic spectrum from gamma to radio waves.