Video Frame Cropper failed, stalled, or looks wrong? Troubleshooting
Troubleshoot Video Frame Cropper by codec, container, parameters, memory, and browser while respecting quality and device boundaries.
Do not rename an extension to fake a format
An extension names a container, not a guaranteed video/audio codec. Keep the source and record size, duration, codec, dimensions, browser, and exact error. Never overwrite the only original repeatedly.
The easy-to-miss issue for this tool
When cropping landscape to 9:16, scrub the timeline to keep the subject in frame. A fixed crop does not track a moving person.
Recommended troubleshooting order
- Load a very short, low-resolution known-good sample to confirm the tool starts.
- Check whether duration, video, audio, and dimensions are detected; missing metadata often means damage or an unsupported codec.
- Reduce duration, resolution, frame rate, or simultaneous file count.
- Close heavy tabs, retry in current desktop Chrome/Edge, and keep the page active.
- Reapply the workflow:
- Choose video and read its source dimensions.
- Enter crop X, Y, width, and height.
- Set quality and audio bitrate, then process.
- Inspect actual crop bounds, subject placement, and output dimensions.
- If it still fails, use desktop FFmpeg or the producing application; do not claim browser support for that codec.
Parameter checks
- Crop X
- Crop Y
- Crop width
- Crop height
- Quality / CRF
- Audio bitrate
Common errors
Why does the subject leave the frame later?
The current crop is fixed and does not track people or objects.
Why is an edge one pixel different?
Encoder pixel formats often require even bounds and use safe alignment.
Is video uploaded?
Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task.
Boundaries that cannot be bypassed
- Discarded regions cannot be restored
- No draggable region, aspect preset, or subject tracking is currently provided
- Crop coordinates must fit the source and dimensions must be even
Browser WASM lacks the full performance and codec set of native apps, and long video can take substantial time. A paused progress display does not mean server upload; processing is in the tab, but the browser can terminate it under memory pressure.
Privacy, rights, and open-source licenses
Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task. Troubleshooting images and outputs can still contain private, copyrighted, or hidden metadata. The ffmpeg.wasm wrapper is MIT and this release's FFmpeg core is GPL-2.0-or-later; source access and license notices must not be removed.