How to Remove Metadata from Video Files

What “video metadata” actually includes

A video file is usually a container holding one or more encoded video, audio, subtitle, image, or data streams. The container can carry global tags such as title, author, comment, creation time, location, device, or software. Individual streams also have technical descriptors such as codec, resolution, frame rate, sample rate, language, duration, and bitrate.

The technical descriptors are normally required to play or identify the streams. Removing them all would not produce a useful file. The privacy review should focus on descriptive tags and identifiers rather than expecting the codec or resolution to disappear.

How to remove supported video container metadata

1. Keep an original. Remuxing creates a different container file even when encoded media streams are copied unchanged.
2. Select the video locally. Open the video tool and choose a common supported container such as MP4, MOV, MKV, WebM, AVI, WMV, or MPEG.
3. Wait for the media engine. FFmpeg JavaScript and WebAssembly resources are downloaded when the audio/video path is first needed; the selected video itself is not sent to that resource host.
4. Review detected tags. Look for creation time, location, make/model, software, title, author, comment, copyright, and other descriptive fields.
5. Create the cleaned copy. metapeel invokes FFmpeg with stream mapping, disabled global metadata copying, and stream copy.
6. Play and inspect the result. Verify both media compatibility and the tag fields that matter to you.

The exact FFmpeg cleaning boundary

The active command follows the same concepts documented in the FFmpeg command reference: map the input streams, disable automatic global metadata copying with -map_metadata -1, and copy encoded streams with -c copy.

An output muxer may also write a neutral format or encoder tag. That is different from retaining the original author, device, GPS, or creation-time value, but it should still appear during verification.

Does remuxing change video quality?

With stream copy, FFmpeg copies the encoded packets rather than decoding and compressing the picture and sound again. That avoids transcoding loss. The container itself is rebuilt, so byte-for-byte file identity, signatures, chapter behavior, attachments, unusual stream layouts, and player compatibility are not guaranteed to remain unchanged.

Container support is also codec-dependent. A filename extension accepted by the picker does not guarantee that every unusual codec or malformed file can be remuxed back into that container. The FFmpeg formats documentation is the source of truth for demuxer and muxer behavior; the browser build can still impose memory and compatibility limits.

What stays local, and why large videos take longer

The file is written into the browser-hosted FFmpeg virtual file system and processed on the user's device. metapeel does not upload its contents for server-side conversion. FFmpeg code and its WebAssembly core are downloaded on demand, which is a resource request—not a file upload.

Browser processing needs memory for the input, virtual file, and output. Large or complex videos can exhaust memory on a phone or low-memory computer. Close unnecessary tabs, keep the original file, and test with a short non-sensitive sample if you are unsure whether a container/codec combination will work.

How to verify the cleaned video

1. Play the entire cleaned copy, checking video, audio, subtitles, orientation, chapters, and seek behavior that matter to you.
2. Load the output into metapeel again and compare the descriptive fields with the original.
3. For an independent inspection, run ffprobe -show_format -show_streams cleaned.mp4. The ffprobe documentation explains how format and stream information is reported.
4. Expect codec and other technical stream descriptors to remain. Investigate original GPS, make/model, author, comment, creation-time, or software values if they still appear.

Audio uses the same local remuxing engine but different tagging conventions. See the audio metadata guide, or return to the cross-format metadata map for the wider picture.