When the image resolution on AIBooru differs from the image resolution at the source. The following two tags can be used with this tag.
height_source <= height_aibooru and width_source <= width_aibooru
height_source >= height_aibooru and width_source >= width_aibooru
(height_source > height_aibooru and width_source < width_aibooru) or (height_source < height_aibooru and width_source > width_aibooru)
This tag implicates md5_mismatch (learn more).
The following tags implicate this tag: source_larger and source_smaller (learn more).