When crop tool is used, a new manual placement mode constraining the recteangle to the area occupied by source image pixels.
This new mode would disallow moving the target rectangle outside of the image (rendered black in the tool canvas).
Existing unconstrained mode would still be retained.
This proposal extends the thread cited below so that bounded cropping would work regardless of the reason why the source image is unknown (black) : unrotated original rectangle, rotated source, warped source using perspective corrections, and in the future maybe, panorama stitching, composite images, etc …
I like this idea. Too often, the automatic crop modes don’t maximize the cropped area or position it where I want it to be. Being able to quickly and easily push the crop boundaries out to the edges of a rotated & perspective-corrected image without having to zoom in at every corner and make careful micro-adjustments would be very helpful. It would need to be a mode that is easily turned on and off, because I also like to freely crop an image beyond its borders and paint in the missing parts.
But I might even want to change the proportions of the crop, or go freeform, so I’m really not bothered if I have to adjust things slightly. After all, if the software did everything for me, is it still my picture?
Description edited : The formulation is made so that this feature would work regardless of the reason why the source image is unknown (black) : unrotated original rectangle, rotated source, warped source using perspective corrections, and in the future maybe, panorama stitching, composite images, etc …
I agree this is an important feature. Joanna’s example above is a good one. In her example it is practically impossible to move the default crop box up and to the right or down and to the left while keeping the crop box the same while at the same time not including any black pixels where there was no source image. There should be an option (it can be a check box along the bottom of the image next to the aspect ratio selection) that says “constrain to image area”.
Check it, and the box isn’t allowed outside the image area. Unchecked and it is allowed outside. Also this setting should be global and not per image. So when I’m cropping a number of images I don’t have to check the box for each image.