Video Upscaler (fal)

The straightforward video upscaler in the pack: point it at a clip, tell it how much bigger, get a larger clip back. It's the plainer, cheaper alternative to the Topaz node when you don't need Topaz specifically. The one thing to get right before you wire it up is that it works entirely in URLs - it takes a URL in and gives a URL out. No video socket at all.

Cloud call, per-clip billing, nothing local.

How it works

Video upscaling is the temporally-aware cousin of image upscaling - the model has to keep consecutive frames consistent, or fine textures shimmer and the result is unwatchable. This node hands the job to fal's video upscaler. You give it the URL of a clip already sitting on fal and a scale factor; it renders a higher-resolution version and returns the new URL.

Because the input is a URL, not a video file, there's a small bit of plumbing to know about (below).

The inputs and outputs that matter

• video_url (required, STRING) - the clip to upscale, as a fal URL. This is not a VIDEO socket. If your video is local, you first run it through UploadVideo_fal to get a URL, then feed that here. Or chain it from another fal node whose output is already a URL.
• scale (default 2, range 1–4 in 0.5 steps) - the multiplier. 2× is the default; higher costs more and takes longer.

Output is a STRING - the URL of the upscaled clip on fal. Download it with the pack's Fal Save Media from URL node, or pass it straight into another fal node's *_direct_url to keep the pipeline entirely URL-to-URL (the media never touches your machine). Save it before it expires.

How to install it

Part of gokayfem's ComfyUI-fal-API pack. ComfyUI Manager: search ComfyUI-fal-API, install, restart. Manual:

cd ComfyUI/custom_nodes
git clone https://github.com/gokayfem/ComfyUI-fal-API.git
pip install -r ComfyUI-fal-API/requirements.txt

Add your fal key (copy config.ini.example → config.ini, paste from fal.ai/dashboard/keys, or export FAL_KEY=your_key), restart.

Common issues & troubleshooting

"How do I plug my local video in?" You can't - directly. This node wants a URL. Put an UploadVideo_fal node in front of it: local VIDEO → UploadVideo_fal → its video_url output → this node's video_url input.

Which upscaler should I use - this or Topaz? Topaz is the benchmark for quality and accepts a local VIDEO directly (no upload step). This node is the leaner, cheaper option and is handy when you're already working URL-to-URL in a fal chain. For a decent source where you want speed and low cost, this is fine; for the best result on tricky footage, Topaz.

Cost on long clips. Video upscaling is billed per clip and scales with length and factor. Test on a short segment first.

Output won't preview. It's a URL - download it via Fal Save Media from URL.

Insufficient funds / credit lag. fal is pay-per-call and legit; top-ups have occasionally posted late. Wait for credits rather than repaying. fal's errors print as text in ComfyUI.