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November 8

ImageMagick

I'm trying to use ImageMagick to crop a bunch of images of various sizes. I want to remove the leftmost 10% and the rightmost 10% of each image. Let's say the image is 1000 width by 1000 height, I want to remove the leftmost 100x1000 rectangle, and the rightmost 100x1000, so that I end up with an resulting image of 800 width by 1000 height. Reading its manual[1], this is seems easy to do using the -crop command if all the images sizes were identical, so that I can pre-calcuate the crop rectangle XY coordinates in advance. But when the input images have different dimensions, I can't seem to find a way to use percentage values to specify the crop rectangle size and location. Any and all help would be much appreciated. Mũeller (talk) 12:28, 8 November 2018 (UTC)[reply]

@Mũeller: The section you linked tells you see Image Geometry for complete details about the geometry argument. A bit more hunting finds that page, based on which I guess (without having tested it) that what you want is -gravity Center -crop 80x100%+0+0 image.out. It does not seem possible to specify offsets in percentages, but since you want to crop an equal amount left and right, you can crop "from the center". Tigraan^{Click here to contact me} 12:43, 8 November 2018 (UTC)[reply]

This post on the imagemagick forum gives some examples of how to crop offsets in percentages EniaNey (talk) 15:04, 14 November 2018 (UTC)[reply]

Thank you so much! That worked perfectly! Mũeller (talk) 15:19, 8 November 2018 (UTC)[reply]

Resolved