Meld Instant Pixelate

Pixelation looks easy but is annoyingly easy to get wrong - do a naive resize and you get mushy anti-aliased edges instead of chunky clean blocks. Meld Instant Pixelate does it the right way: downscale with area averaging, then upscale back with nearest-neighbor. Two steps, one node, and you get sharp-edged mosaic blocks at the original resolution.

It's part of ComfyUI-Meld, and it's one of the pack's "sandbox" nodes - the little image utilities that have nothing to do with the Image Manager. Perfect for retro pixel art styling or for slapping a mosaic over something.

The one input that matters

• image - anything, including batches.
• pixel_size (default 16, range 1–256) - the size of the pixel blocks in pixels. Higher = bigger blocks = coarser mosaic.

That's the whole surface area. Feed it an image, pick a block size, get a pixelated image back at the same resolution.

Why the two-step trick matters

The reason it looks better than a single "pixelate" resize is the downscale stage. It uses area interpolation - effectively averaging each block's colors - so each block becomes the mean of the pixels underneath it. That preserves the image's overall tones and features, which is what makes small pixel_sizes (4–16) read as "retro game sprite" rather than "subsampled garbage." The upscale back to full size then uses nearest interpolation, which keeps the edges blocky and sharp instead of blurring them back into a smudge.

Where you'd reach for it

• Pixel art style: pixel_size 4–16 on an already-stylized render.
• Censoring: pixel_size 32+ produces a proper mosaic. Combine with a mask node upstream so only the face (or whatever) gets pixelated - the node itself has no mask input, so do the masking before it and composite after.
• Thumbnails / privacy exports: a coarse pass over a full image before sharing.

Installing it

Ships in ComfyUI-Meld - install the pack once:

• ComfyUI Manager → search "Meld" → install, or
• comfy node install HappyOnigiri/ComfyUI-Meld, or
• cd ComfyUI/custom_nodes && git clone https://github.com/HappyOnigiri/ComfyUI-Meld.git && cd ComfyUI-Meld && pip install -r requirements.txt then restart ComfyUI.

No model files, no API, no extra inference - it's pure tensor reshaping, so it runs instantly even on huge images.

Honest note: if all you need is one-off pixel art, plenty of packs do this. What Meld brings is that it's built into a pack you might already have installed for the Image Manager, it handles batches, and the output resolution never surprises you. Not the flashiest node on the graph - but the two-step downscale/nearest method is the difference between clean blocks and blurry mush, and this one gets it right.