Batch Subtitle Streams

Batch Subtitle Streams is the least-searched node in ComfyUI Core Video Nodes (Immac/ComfyUI-CoreVideoMocks), and honestly that tracks - it's the quietest placeholder in the pack. Its proposed job: gather multiple subtitle streams into a batch so you can pull out the one you want. And the "multiple subtitle streams" idea is real, even if it sounds exotic - a file with English, French, and Spanish caption tracks, or the full subs plus the forced-subtitles-only track. Muxed files carry them all.

Two required inputs, both force-input STRINGs: subtitle_stream_1 and subtitle_stream_2. One output, batched_subtitle_streams, a STRING. In the pack's API sketch you'd pipe this into Get Subtitle Stream with a stream_index to choose a track. Same batch-then-select pattern as its video and audio siblings - the pack is consistent about that, at least.

What actually happens

The output is a string echoing both inputs back: "Mock Batched Subtitle Streams: ... + ...". No subtitle is parsed, no batch exists, nothing is captioned. This pack is what its GitHub description says - "A set of mock nodes for RFC purposes" - and the author's README admits it's "a mock of a possible implementation" of future core video nodes. Two stars, no community footprint, untouched since March 2025. This node is a sketch of an API, drawn in the faintest pencil.

Install

cd ComfyUI/custom_nodes
git clone https://github.com/Immac/ComfyUI-CoreVideoMocks

Restart ComfyUI. No pip dependencies, no models, no ffmpeg - pure Python on ComfyUI's own folder_paths, or via ComfyUI Manager ("ComfyUI Core Video Nodes").

Verdict

If you're a beginner, the one genuinely useful thing here is learning that subtitle tracks live inside a video container and can be selected independently - that's a real concept that trips people up. If you're looking for working subtitle handling, that's ffmpeg (or a tool like Subtitle Edit), not this. Skip this node for anything but curiosity; it's the pack's most honest-to-goodness nothing-burger.