Easy Image Batch (Koolook)

Easy Image Batch is a frame-accurate timeline builder for VFX work: it takes a handful of image slots and turns them into a full-length image batch with placeholders filling the gaps. You know how a compositor works - render a few key frames, leave black or gray for the rest, build the cut, check timing - before you commit to rendering everything. That's this node.

It's built around 1-based VFX frame numbers, because real plate pipelines number frames from the shot's start, not from zero. You give it a cut_start_frame (the first VFX frame your output represents), a total_frames window, and it lays out a batch where your connected images land at their specified frame numbers and everything else is placeholder_color.

How it works

The core is image1 through image4, each with an imageN_frame widget that says which VFX frame that image sits at (defaults of 5, 9, 13, 17 - spread out, but you'll change them). Unwired slots are ignored. Beyond that there are two heavier modes:

• source_frames - a free-form 1-based frame list (commas, spaces, tabs, newlines; 14-17 expands to 14,15,16,17). With keyframes_insert connected, a packed sequence gets inserted onto the timeline at those exact positions: first frame → first number, second → second, etc. Without a source batch, the gaps fill with placeholder color ("offset/reconstruct mode"); with one connected, inserts composite over the source frames in the cut window.
• source_batch - a background plate. When connected, it becomes the backdrop for the whole window and the inserts land on top.

The output is more useful than a plain image: image_batch is the assembled frames, alpha_batch is a MASK where selected frames are black and empty frames are white (flip it with invert_alpha to get a comp-ready holdout), selected_image_batch is just the frames you actually placed, and selected_frames tells you which VFX frame numbers those were. If you're building a cut where an upstream node only needs the real frames, that last pair saves you a lot of slicing.

The inputs a beginner actually sets

Three, honestly. cut_start_frame and total_frames define the window, and placeholder_color decides whether the gaps read as "empty black" or "preview gray." Everything else - the image slots, the insert mode, the source batch - you add as your workflow gets more elaborate. width/height only matter in the fully-empty case (a clean placeholder batch); once any image is connected, its dimensions win.

Install

Part of the ComfyUI-Koolook pack. Manager → Install Custom Nodes → Git URL:

https://github.com/malkuthro/ComfyUI-Koolook.git

Or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/malkuthro/ComfyUI-Koolook.git

Restart, and it's under Koolook/Image. No models, no dependencies beyond what ComfyUI already ships. As with everything in this pack, install it exactly once - a Manager install is custom_nodes/koolook/, and a second git clone creates a parallel install that double-registers everything and corrupts the workflow store on each boot until you remove one folder.

Common issues

• Frames land one off - everything here is 1-based. Frame 5 means VFX frame 5, and output index 0 represents cut_start_frame, not frame 1.
• Empty frames are white when you expected black - check invert_alpha and placeholder_color; the alpha semantics (selected = black/0 by default) are easy to flip by accident.
• The keyframe_batch input you saw in an old workflow - that's a deprecated alias for keyframes_insert, kept so pre-rename workflows still load. Use the new name; the old one is ignored when both are connected.