fix: cleanup FFmpeg temp files after export

[divyanshi-adhikari]

Fix: Cleanup FFmpeg temporary files after export

Problem

While exporting videos using FFmpeg WASM, temporary input/output files were being created inside the virtual filesystem but were not always properly deleted after the export process.

This caused:

• Accumulation of temporary files across multiple exports
• Increased memory usage over time
• Potential risk of file conflicts in repeated exports

What was changed

• Ensured input file is always deleted after export using finally block
• Added safe cleanup for output files
• Added fallback cleanup for failed export scenarios
• Improved reliability of FFmpeg virtual filesystem management

How it was tested

• Ran multiple export cycles consecutively
• Verified no leftover files remain in FFmpeg virtual filesystem
• Checked memory usage in Chrome DevTools Performance Monitor
• Confirmed export works correctly in both success and fallback cases

Issue reference

Fixes #11

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[github-actions]

👋 Thanks for your PR, @divyanshi-adhikari!

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Happy coding! 🎉

[magic-peach]

Hey @divyanshi-adhikari! Cleaning up FFmpeg temp files is a great idea, but the implementation has a significant regression.

Issues:

1. Removes multi-format support — The original code supported webm, mkv, and mp4 export formats via getOutputConfig(). Your PR removes this entirely and hardcodes output to output.mp4 only, breaking WebM and MKV export.

2. Removes abort signal from fetchFile — The line await ffmpeg.writeFile(inputName, await fetchFile(file)) drops the { signal } parameter, which means the file write can't be cancelled anymore.

3. Simplified filenames can cause collisions — Using input. and output.mp4 as fixed names means concurrent exports (or rapid re-exports) could clobber each other. The original sessionId-based names prevented this.

What to do:

• Keep the original getOutputConfig() and session-based filename approach
• Only add cleanup logic (e.g., ffmpeg.deleteFile() in the finally block) without changing the existing logic
• Keep the { signal } parameter in the fetchFile call

Thanks for working on this — just needs a more surgical fix!

[magic-peach]

Hey @divyanshi-adhikari! Thank you for working on FFmpeg temp file cleanup — that's a real issue. However, this PR has significant regressions:

1. Removes multi-format export support: The original code handles MP4, WebM, and MKV output formats. Your version only outputs MP4 (hardcoded output.mp4). This breaks the format selector UI.

2. Removes abort signal from file write: await ffmpeg.writeFile(inputName, await fetchFile(file)) drops the { signal } parameter — this means cancelling an export won't interrupt file writing, making cancellation unreliable.

3. Removes session-based filenames: The session ID in filenames prevents collisions if multiple exports run. Hardcoding input.ext / output.mp4 could cause issues.

The cleanup intent is valid — if you want to add ffmpeg.deleteFile() calls after export, please do so without removing the multi-format support, abort signals, or session IDs.

[divyanshi-adhikari]

Thanks for the review. I’ve updated the PR as per your feedback and reverted the unintended changes.

The multi-format support, session-based filenames, and abort signal handling are all preserved now, and I’ve only added the FFmpeg cleanup logic in the finally block.

[magic-peach]

Hey @divyanshi-adhikari! The build is now passing on this PR, but it has merge conflicts with main that need to be resolved. Please rebase your branch:

git fetch upstream
git rebase upstream/main
# resolve any conflicts
git push --force-with-lease origin <your-branch>

Once the conflicts are resolved and CI passes on the updated branch, this will be reviewed for merge. Thanks!

[magic-peach]

Hey @divyanshi-adhikari! Cleaning up FFmpeg temp files is a good memory management improvement. This PR has merge conflicts with main. Please rebase:

git fetch origin
git rebase origin/main
git push --force-with-lease

[magic-peach]

Hey @divyanshi-adhikari! This PR needs a rebase on the latest main to trigger fresh CI checks. Please run:

git fetch origin
git rebase origin/main
git push --force-with-lease

Once CI (build/lint/typecheck) passes, we'll review and merge!

[magic-peach]

Hey @divyanshi-adhikari! This PR looks interesting (FFmpeg temp file cleanup). The build/lint/typecheck CI hasn't run yet. Please rebase onto the latest main to trigger fresh checks:

git fetch upstream && git rebase upstream/main && git push --force-with-lease

Once CI passes, we'll review and merge!

[magic-peach]

Hey @divyanshi-adhikari! 👋

We've added a new requirement for all PRs: a screen recording showing your changes working on your local machine must be attached before a PR can be merged.

Please add a recording to this PR that shows:

1. bun run dev running at http://localhost:3000
2. The full working flow of your change (demonstrate the feature/fix end-to-end)
3. Any tests passing — if your change touches logic with tests, show bun run lint and bunx tsc --noEmit completing without errors in the terminal

How to record:

• macOS: Cmd + Shift + 5 → Record Selected Portion, or QuickTime Player
• Windows: Win + G → Xbox Game Bar → Capture
• Linux: OBS Studio, GNOME Screenshot, or kazam
• Any OS: Loom (free, easy to share)

Once you have the recording, drag the file directly into a comment on this PR, or paste a Loom link. This is now a hard requirement — see CONTRIBUTING.md for full details.

Thanks for contributing to Reframe! 🎬

[divyanshi-adhikari]

Hi @magic-peach
Here is the screen recording demonstrating the changes working locally:

ffmpeg.ts.-.reframe.-.Visual.Studio.Code.2026-05-19.14-32-00.online-video-cutter.com.mp4

[divyanshi-adhikari]

Hi @magic-peach I hope you are doing well.

Sorry if I’m bothering you. I just wanted to kindly ask if you could give me a brief idea of when this PR might be merged. I would be really grateful.

Thank you.

[divyanshi-adhikari]

Can you please add gssoc:approved label to it.

[magic-peach]

Hey @divyanshi-adhikari! Cleaning up FFmpeg temp files after export is an important fix to prevent OPFS/memory leaks. This PR has merge conflicts with main that need to be resolved:

git fetch origin
git rebase origin/main
# resolve any conflicts
git push --force-with-lease

Once rebased and CI (build/lint/typecheck) passes, this will be reviewed for merging. Thanks!

[divyanshi-adhikari]

Hi @magic-peach I have resolved the conflict. And also, can you please add gssoc:approved tag instead of gssoc'26 I be really grateful.

Thank you!

[magic-peach]

@divyanshi-adhikari Cleaning up FFmpeg temp files with a finally block is an important fix to prevent memory leaks on repeated exports! Please resolve the merge conflicts with main:

git fetch origin
git rebase origin/main
git push --force-with-lease

Regarding the gssoc:approved label — that can only be added by a human maintainer after reviewing the contribution. Once CI passes and conflicts are resolved, we'll flag this for maintainer review to get it approved.

Once CI (build/lint/typecheck) passes, this will be ready for merge!

[divyanshi-adhikari]

Hi @magic-peach, I hope you are doing great.

I have solved the conflicts. Please check