vae tiling improvements: encoding support and adaptative overlap

[stduhpf]

• Added a boolean argument sd_tiling() function, specifying if the output tile is scaled up (for decoding) or if the input is (encoding).
• Added a mechanism to automatically fix the tile overlaps in cases of mismatch between image size and tile size.

With these changes, vae encoding can now be tiled, and a small (unreported?) issue with the upscaler over-brightening some parts of the image is now fixed. This could also be a step toward tiled diffusion support.

[Green-Sky]

• Added a mechanism to automatically fix the tile overlaps in cases of mismatch between image size and tile size.

With these changes, vae encoding can now be tiled, and a small (unreported?) issue with the upscaler over-brightening some parts of the image is now fixed. This could also be a step toward tiled diffusion support.

Nice! It would also be interesting to see larger tile sizes. Depending on VAE, larger tiles would still fit into the memory budget and would speed things up.