How to Hide Faces in MP4, MOV, and WebM Videos

MP4, MOV, and WebM are video containers. Whether Unseen can process a particular file also depends on the codec inside it and what your browser can decode. An MP4 that plays on one device may fail on another.

Start by opening a short example from the same camera or app you plan to use. If it loads, anonymize a small section and check the export before working through the full recording.

Import the file and check orientation

Open Unseen, select your processing mode, and choose the video. Before starting detection, confirm that the picture is upright and has the expected dimensions.

Phone recordings can use orientation metadata, and a file can appear correct in one player while another interprets it differently. If your preview is sideways, rotate and export a corrected copy in a video editor before proceeding. Do not try to compensate by selecting faces in a misoriented view.

Local inputs are capped at roughly 2 GB in this checkout. Cloud inputs are capped at 500 MB and ten minutes for ordinary anonymization. The import screen shows the applicable limits.

When the file will not open

Try these in order:

1. Play the source in the same browser.
2. Check that the file is fully downloaded rather than a cloud placeholder.
3. Try a short sample exported from your existing video editor.
4. If necessary, convert a copy to a broadly supported format such as MP4 with H.264 video and AAC audio.

Conversion should happen in a trusted tool, especially if you chose local face processing to avoid uploading sensitive footage. Renaming a file from .mov to .mp4 does not convert its contents.

Do not discard the original after making a compatibility copy.

Check more than the extension on export

After processing, choose Export video and look at the filename and file type actually provided. The output format can depend on the processing path and browser. Do not assume a MOV input will produce a MOV download.

Open the exported file in the app where you intend to use it. Check picture, sound, orientation, duration, and the final second. A browser preview working correctly is useful evidence, but it is not the same as successful import into your editing or publishing app.

Why a smaller file can still be difficult

File size is a poor proxy for processing effort. A highly compressed video can still contain many high-resolution frames. A short clip with fast camera movement and crowded faces can be harder to track than a larger file showing a stationary speaker.

If performance is poor, test a shorter cut before reducing resolution. Shrinking the picture can make already-small background faces harder to detect.

Once compatibility is confirmed, follow the face-blurring tutorial. If timing or picture quality is the remaining issue, the resolution and compression guide explains what to inspect.