Launched this week
Supra Player
Compare & Sync Videos Fast
172 followers
Compare & Sync Videos Fast
172 followers
Supra Player is a lightweight macOS app built for reviewing, comparing, and syncing video. Compare up to 12 videos side by side with frame-accurate playback, automatic audio sync, shared zoom and pan, customizable layouts, annotations, and instant switching—without the complexity of a full video editor.
Supra Player
the sneaky part of mixed-fps review: a 24fps clip and its 60fps interp share an instant only every 1/12s, so stepping both one frame drifts them apart. nearest-pts snap on the slower clip keeps it honest.
Supra Player
@qifengzheng Thanks! You're correct and I ran into this while reviewing interpolated videos myself. The app syncs on timestamps, not frame numbers. During playback there's a single global timeline, and each clip maps that timeline to its own source time. Frame stepping uses the highest-FPS clip, so if you're comparing 100 FPS against 25 FPS, the 25 FPS clip only advances every 4 key presses while the 100 FPS clip advances every press.
I added an overlay showing each video's current frame, total frames, and FPS, which makes this really obvious.
The pixel difference mode is also surprisingly useful here—you can literally watch the clips diverge between matching frames, then flash back to identical every time they land on the same source frame.
Whenever you pause, play, or scrub, every clip is re-seeked to the exact timeline position. Playback start is also dynamically staggered—the more videos there are, the more the startup is spread out (up to ~100ms for larger sessions) to reduce decode spike / overload and subsequent de-sync. Each clip is compensated for its delayed start so they still begin in sync. Together these help keep everything aligned while reducing decode spikes and improving playback on older hardware with multiple high-resolution videos.. oh and there is a duration lock button if you really need it.
Pixel diff mode :)
video metadata overlay :)
Frame-accurate multi-cam sync via audio analysis is the feature that makes this actually useful for real production work. Syncing multi-cam footage manually is one of those jobs that silently steals 30 minutes from every edit session - doing it automatically with a single click is the right call.
The 12-panel limit covers any realistic multi-cam setup. One edge case I'd be curious about: does it handle mixed frame rates side by side (say, 24fps B-roll next to 60fps slow-mo)? That's where most video comparison tools fall apart. Congrats on the launch.
Supra Player
@galdayan Thanks Gal! Great question. It should handle mixed frame rates just fine. I've been using it myself extensively to review frame interpolation tests (RIFE, etc.), where clips often have different frame rates.
For syncing, as long as the videos have enough overlapping audio, one-click sync works reliably. I've tested it with everything from clean recordings to street ambience and background music, and it's held up well. If needed, you can also nudge clips left or right by a frame using the sync timeline for fine adjustments.
Love the idea of keeping reviewing separate from editing. There are plenty of times I just want to compare outputs, not open a full NLE project.
One workflow I'd find really useful is comparing multiple AI-generated versions side by side (upscaled, restored, interpolated, etc.) and being able to bookmark specific frames where one model performs better than another. That would make model evaluation much faster.
Supra Player
@prashant_patil14 Thanks Prashant! Exactly my thoughts and what led to the birth of this app :)