How to fix drone video corrupted after a crash
When a drone crashes, loses its battery or freezes mid-flight, the last video file usually keeps its frames but loses the index that players need, so it will not open. Recover the memory card, let the drone power on with the card inserted (many models close unfinished files at boot), keep the low-resolution copy from the controller or app, and if the main file is still broken, rebuild its MP4/MOV index using a short reference recorded on the same drone with the same settings. The FixMP4 repair tool does the rebuild in your browser with a free preview. For DJI aircraft, see the dedicated DJI guide.
Brand checklist
| Brand / type | Typical files | Supported | Notes |
|---|---|---|---|
| DJI (Mini, Air, Mavic, Avata) | MP4/MOV, H.264/H.265 | Yes | See fix DJI video |
| Autel (EVO, EVO Lite, EVO Nano) | MP4/MOV, H.264/H.265 | Yes | Match Log/Normal colour mode in the reference |
| Skydio (2, 2+, X10) | MP4, H.264/H.265 | Yes | Use the same capture mode and resolution |
| Parrot (Anafi family) | MP4, H.264/H.265 | Yes | HDR and P-Log modes change settings |
| FPV with GoPro or naked GoPro | MP4 | Yes | See fix GoPro video |
| FPV with Insta360 / Caddx | MP4 (flat) or 360 formats | Flat MP4 only | See fix Insta360 video |
| FPV goggle DVR (analog or digital) | MP4, TS or AVI | MP4 only | Goggle DVR settings differ from the air unit |
| Thermal / mapping payloads | Proprietary or radiometric formats | Usually no | Use the vendor's software |
What happens in a crash
Drone cameras write compressed frames to the card continuously and write the file's moov atom index when recording stops. A crash that ejects the battery, a deep discharge that cuts power, a hard impact that unseats the card, or a firmware freeze all stop recording before the index is written. The data written up to that moment remains on the card, which is why a repair usually recovers the flight up to a fraction of a second before impact. Background: what the moov atom is.
Step by step
- Recover the card. If the drone is lost, the controller or phone app cache is the only copy; export it before clearing app data.
- Do not record on that card and do not format it.
- Power the drone on with the card inserted and wait a minute; many aircraft finish interrupted files.
- Copy the card to a computer with a card reader.
- Record a reference on the same aircraft, on the ground, with the same resolution, frame rate, codec (H.264 or H.265) and colour profile (Normal, Log, HDR).
- Rebuild the broken file in the repair tool, check the free preview and export with a subscription.
Reading the preview after a crash
The end of a crash recording often shows violent motion and smearing; that is the real footage. Blocky or grey frames from the very start, by contrast, mean the reference does not match. A sudden stop a few seconds before the impact usually means the card stopped accepting data, not that the repair failed; check the card in another reader.
Controller and app caches
Most consumer drones stream a lower-resolution live view to the controller or phone and cache it. Autel Sky, Skydio's app and DJI's apps all keep some form of cached or recorded view. It is not broadcast quality, but for incident analysis it is often enough. Some smart controllers can also record their screen.
Flight logs
The aircraft and app keep detailed flight logs (position, altitude, battery, errors). These are separate from the video and are far more useful than the video for working out why a crash happened. Export them alongside the footage for insurance or warranty claims.
How the rebuild works
FixMP4 reads the broken file's media data directly from your disk, recognises every H.264 or HEVC frame by its NAL unit structure, takes stream parameters from your reference clip, rebuilds timing, B-frame reordering and keyframes, and writes a new index. If the drone records AAC audio, audio frames are parsed and rebuilt too; most drones have no microphone. Nothing is re-encoded or uploaded.
Common mistakes
- Flying again with the same card "to test the drone" and overwriting the crash file.
- Recording the reference in a different colour mode; Log profiles usually switch the encoder to 10-bit.
- Throwing away the app cache before checking whether the main file can be repaired.
- Repairing an FPV goggle recording with an air-unit reference, or the other way round.
When the repair finds nothing
If the repair tool reports that no video could be recovered, the file may be empty (0 bytes), contain only zeros because the card never received the data, or use a format the tool does not read. Check the size, then see MP4 is 0 bytes and our guide to recovering video from a corrupted SD card.
Keep both the original broken file and the repaired copy.
Prevention
- Use V30 or faster cards and format them in the aircraft.
- Land with battery margin, and keep firmware updated.
- In risky manoeuvres or near obstacles, start a new recording periodically so a crash affects only a short file.
- Secure the card slot cover; impacts can unseat cards.
Related guides
FixMP4 compared with other options
| Feature | FixMP4 | Desktop repair suites | untrunc (CLI) | VLC |
|---|---|---|---|---|
| Runs where | Browser, on your device | Desktop app | Command line | Desktop player |
| Keeps your file on your device | ✓ | ✓ | ✓ | ✓ |
| Nothing to install | ✓ | ✕ | ✕ | ✕ |
| Rebuilds a missing MP4/MOV index | ✓ | ✓ | ✓ | ✕ |
| Preview of your own repaired file before paying | ✓ | Trial (varies) | Free tool | n/a |
| Voice Memos / AAC without a reference | Usually | Varies | ✕ | ✕ |
| Formats beyond MP4/MOV/M4A | ✕ | ✓ | Many (FFmpeg) | Plays many |
Frequently asked questions
Can drone footage be recovered after a crash?
Usually, if you recover the memory card. The frames are on the card; only the MP4 or MOV index is missing, and it can be rebuilt with a reference clip from the same drone and settings.
Which drones does FixMP4 support?
Any drone that records MP4 or MOV with H.264 or H.265, including DJI, Autel, Skydio and Parrot. Proprietary thermal and 360 formats are not supported.
What if the drone is lost?
Then only the lower-resolution cached view on your controller or phone remains. Export it from the app.
Why does the repaired video stop before the crash?
The camera may have stopped writing a moment earlier, or the card stopped accepting data. The repair recovers everything that reached the card.