.ACV File Extension

Adjustment curve created by Photoshop, a professional image-editing application; stores modifications that can be applied to digital photos and other images; commonly used to fine tune RGB colors and tonality before printing, or for correcting images for digital publishing.

Curves allow users to alter an image by adding modification points to the color and tone curve. ACV files can be created by selecting Image → Adjustments → Curves... and then saving the changes from within the Curves window.