ComfyUI Speeds Up MiniMax H3 Video VAE Encoding and Decoding

ComfyUI's update makes the MiniMax H3 video VAE encode up to about 2.2x faster and decode 1.4-2.7x faster, cutting a 1344x768, 129-frame round trip on an RTX 5090 from 24.3 to 12.7 seconds.

The gains come from a fused encoder kernel enabled by default, fp16 accumulation support in a custom convolution, and an int8 decoder, and the source says the changes are visually lossless to the eye.

Users need ComfyUI v0.36.0 or above, and the int8 VAE file is a drop-in replacement for the standard one.