ComfyUI Batch Video Loader

ComfyUI Batch Video Loader

A ComfyUI custom node that batch-processes every video in a folder through your existing single-video workflow — no loop nodes, no external scripts.

Loads videos one at a time from a folder. In incremental_video mode it moves to the next file in the folder every time you queue the prompt, so you can batch-process an entire folder by queuing N times (or using ComfyUI's "Auto Queue" / queuing N prompts up front).

This avoids trying to load every video into one giant tensor at once, which is how VHS_LoadVideo works for a single file but isn't practical for a whole folder of videos.

Install

Via git clone (recommended):

cd ComfyUI/custom_nodes
git clone https://github.com/artttaku/ComfyUI-BatchVideoLoader

Or manually: download this repo as a ZIP and extract it into ComfyUI/custom_nodes/ so the path looks like ComfyUI/custom_nodes/ComfyUI-BatchVideoLoader/.

Then:

1. Make sure opencv-python, numpy, and torch are available in your ComfyUI environment (opencv is already a dependency of VHS, so if VHS works, you're set).
2. Restart ComfyUI. You'll find the node under video/batch → Batch Video Loader (Folder).

Recommended: guard against odd-dimension encoder crashes

This package also includes Ensure Even Dimensions (encode-safe) (video/batch category). Insert it between your upscaler's output and VHS_VideoCombine's images input. yuv420p/H.264 encoding requires both width and height to be even numbers — if a scale factor (e.g. 1.5×) lands on an odd dimension for a particular source resolution, the encoder can die mid-write with a cryptic OSError: [Errno 22] Invalid argument. This node crops 1px off the edge only when needed, so it's a no-op for videos that were already fine.

Example wiring (RTX Video Super Resolution + VHS)

1. Delete the existing VHS_LoadVideo node (and VHS_VideoInfo, since this node reports frame_rate directly and VideoInfo isn't needed to drive the pipeline).
2. Add Batch Video Loader (Folder).
3. Set the folder widget to the folder containing your videos.
4. Connect its outputs:
   • IMAGE → Ensure Even Dimensions → RTXVideoSuperResolution.images
   • frame_rate → VHS_VideoCombine.frame_rate (right-click the frame_rate widget on VHS_VideoCombine → "Convert to input" if it isn't already an input socket, then connect)
   • filename → VHS_VideoCombine.filename_prefix (same — convert to input first) so each output file is named after its source video instead of all sharing the same AnimateDiff_00001 prefix.
   • video_info → VHS_VideoInfo.video_info, exactly like VHS_LoadVideo's own video_info output, if you want the source/loaded fps/duration/width/height readout node.
5. Leave mode as incremental_video.

Batch-running it

• Queue the prompt once per video (ComfyUI's queue button, N times), or turn on Auto Queue in the ComfyUI menu and let it rip — it'll stop being useful once the folder wraps around (the counter loops via modulo), so keep an eye on video_index / total_videos in the node output if you want to know when you've done a full pass.
• If you want a single, exact rerun of one file, switch mode to single_video and set index manually.

Widgets

| Widget | What it does | |---|---| | folder | Folder to pull videos from | | mode | incremental_video (advance each queue) or single_video (pinned to index) | | index | Used only in single_video mode | | extensions | Comma-separated list of video extensions to include | | frame_load_cap | Max frames to load (0 = no cap) | | skip_first_frames | Skip N frames at the start | | select_every_nth | Only keep every Nth frame | | force_rate | Override output frame rate (0 = use source fps) |

Troubleshooting

OSError: [Errno 22] Invalid argument in VHS_VideoCombine, on some videos in a batch but not others:

This means the ffmpeg subprocess died mid-encode and Python's next stdin.write() hit the closed pipe — the traceback always points at VHS_VideoCombine, not this loader, since decoding already succeeded by that point. Two known causes:

1. Odd width/height. yuv420p/H.264 needs both dimensions divisible by 2. Fix: use the included Ensure Even Dimensions node (see above) between your upscaler and VHS_VideoCombine.
2. NVENC hardware encoder session conflict. GeForce cards cap the number of concurrent NVENC sessions. Another app doing hardware video encoding at the same time (OBS, Discord, a browser tab, or a stray leftover ffmpeg.exe process from an earlier crashed run — check Task Manager) can cause a new session request to silently fail. This affects specific videos inconsistently and isn't something this node can detect or fix automatically.

To tell them apart: temporarily switch VHS_VideoCombine's format widget from video/nvenc_h264-mp4 to video/h264-mp4 (software encode) and rerun just the failing video. If it succeeds, it was NVENC — close conflicting apps/processes and switch back. If it still fails, it's almost certainly cause #1, or the source file itself has an unusual/corrupt stream worth checking with ffprobe outside ComfyUI.