tiny subimage extractor
Extracts a canvas from the provided image and x, y, width, height region.
image: The source image of typeCanvasImageSourcex: The x-coordinate offset of the subimage in pixelsy: The y-coordinate offset of the subimage in pixelswidth: The width of the subimage in pixelsheight: The height of the subimage in pixelscanvas: The subimage, of typeHTMLCanvasElement
