loops/gdimage (packagist): Import, transform, export images helping GD. This library provides: GIF support, JPEG support, PNG24 support, PNG8 support, animated GIF support, APNG support, HTTP support, data URI support, palette color enhancement (especially on GD transparent color leaks), resizing (crop, fit, filled), color filtering (grayscale, sepia, custom…), convolution (blur, sharpen, invert, custom…), blending (multiply, hard light, overlay, custom…)… I will not detail all the abilities.
Keywords: image|thumbnail|gd|resizing|animated gif|color filter|convolution|APNG|blend mode