The first version swapped a material onto the earcups without changing their outline, so nothing in the result showed that the alpha channel is being inpainted too - the silhouette moved by 47 pixels. The mask now covers both earcups plus a ring of the transparent background around them (25.1% of the frame, 70.9% of it on the headphones), and the instruction asks for the earcups to be rebuilt as oversized turbine cups that flare out past their old outline. The rebuilt region grows 11735 pixels of new silhouette over what used to be empty background, 100% of it inside the mask, while the headband, stitching, yokes and hinges stay pixel-identical (0.27/255 mean channel difference outside the mask). A 25% mask is still clean here; the earlier 16% guidance came from a picture whose mask had far less context left around it. Also verified that the alpha is a real channel rather than a trimmed-off fourth one: re-running with the identical RGB and a fully opaque alpha changes the masked region by 61.9/255 on average (max 254).
5.0 KiB
1024x1024px
5.0 KiB
1024x1024px