SAX Image Preview

Default ComfyUI previews show you one image at a time, which makes "did this tweak help" a game of memory: render A, render B, scroll back, squint. SAX Image Preview fixes that by turning any IMAGE batch into a clickable comparison grid right in the node. Feed it a batch - ideally from SAX Image Collector, which is designed to hand it one - and you get thumbnails to click through and select, with the main view showing your picks side by side. It's the terminal node for every A/B workflow in the pack, and it accepts any IMAGE input, not just collector output.

How it works

Three required inputs and one optional:

• cell_w (default 200, 64–512) - width in px of each cell in the main view. Height is auto-calculated from each image's real aspect ratio, so you're not stretching things into boxes.
• max_cols (default 1, 1–8) - how many columns the main comparison view shows at once. The node's width auto-sizes to cell_w × max_cols. Set it to 2 for a straight before/after, more for a matrix of candidates.
• preview_quality (low/medium/high) - preview resolution. Low caps at 512px (fast, good for "which composition do I like"), medium at 1024px, high is full size (slow, for actual quality inspection).
• images (optional IMAGE) - the batch to display. Wire SAX Image Collector's output here, or any IMAGE tensor.

The UI does the rest: a grid toggle shows/hides the thumbnails, clicking a thumbnail toggles whether that image appears in the main view, a seek bar pages through when your selection exceeds max_cols, and ◀/▶ flip grid pages (fixed at three rows per page). So a batch of 40 candidates becomes: glance at the grid, click the promising ones, compare them properly.

Why it matters

This node is the payoff for the pack's collector design. The whole "render many variants and judge" workflow - the pack's example renders a single mask into two Enhanced Detailer branches, two hair colors, and sends both to the collector - collapses into: generate, click, decide. Without it you'd be saving ten PNGs and flipping between them in a viewer; with it, the decision happens in one place.

The quality knob matters more than it looks. At low, you can judge composition and broad color but not fine detail - which is perfect for the 40-image cull. When you've narrowed to two finalists, flip to high and actually compare the texture. The pack's own estimate for 40 images at 2048px: ~2s at low, ~9s at medium, ~35s at high. Budget accordingly - that's encoding time, not render time.

Installing

Part of the pack:

cd ComfyUI/custom_nodes
git clone https://github.com/so16tm/SAX_Bridge

SAX/Bridge/Output → SAX Image Preview. It's a terminal node (no outputs), so it sits at the end of a comparison branch - and it's exactly the node to reach for when someone posts "these two look identical, help me choose" and you want actual evidence instead of vibes.