Repair a Damaged Video — the Complete Guide (2026)

In short: If your video won’t open, in 8 out of 10 cases it’s merely truncated, not destroyed. The raw frame data is usually still there — what’s missing is the moov atom header that tells the player how to read the file. This guide shows you how to tackle the problem systematically at every level of severity.

This article is the hub for our complete repair strategies. If you want to jump straight to the right path, here’s the quick overview:

• Know which camera made the recording? Jump straight to the device-specific guide in our repair overview.
• Want to understand what’s technically broken? Read the pillar article Understanding the MP4 container: moov, mdat, and why videos break.
• Want to get started right now? Drop your file into our free online diagnosis — you’ll see in 30 seconds whether the file is repairable, and nothing gets uploaded.

What does “broken video” even mean?

Before we compare methods, one thing has to be clear: “file won’t open” is not a single, uniform error. There are at least five fundamentally different damage types, and each one needs a different repair strategy.

Damage type 1: Container header missing (≈70% of all cases)

The most common form. The file has a normal size (e.g. 1.4 GB), but every player says “file damaged” or shows a length of 00:00. Technical cause: the moov atom — the index that tells the decoder where each frame sits in the file — was never written. During recording, the recorder only pumped the raw frames (into the mdat atom) into the file and meant to write the index to the end only on a clean stop. A battery drop, a crash, an accidental card ejection — and the file has no index anymore.

Repair effort: Low to medium. With an intact reference recording from the same camera, the index can be reconstructed. Success rate 90%+.

Damage type 2: Audio drift or audio burst (≈15% of all cases)

The video opens, runs, but the sound has a timing offset of 300–800ms to the picture — or starts with a deafening burst. Technical cause: when the container was rebuilt, the audio stream’s start point was guessed from the raw bytes — and guessed wrong. Or the audio decoder interpreted the first few hundred milliseconds as video bytes, which it rendered as extreme audio values.

Repair effort: Medium. Pro tools correct this automatically; ffmpeg needs manual offset tuning. Success rate 95%+.

Damage type 3: Codec parameter mismatch (≈8% of all cases)

The container is intact, but the decoder finds no valid codec parameters (SPS/PPS for H.264/HEVC). Common after a tool conversion (e.g. MKV→MP4), with HEVC on a hev1/hvc1 tag conflict, or with DiskDrill-recovered files where the codec header comes from the wrong sector.

Repair effort: Medium. Easy with a reference recording (the correct parameters get adopted), hard without one.

Damage type 4: Frame gaps or sector garbage (≈5% of all cases)

The file has gaps in the middle — e.g. 18 frames replaced by garbage bytes because the SD card had a write error. Classic on slow cards with too high a bitrate (e.g. a UHS-I card at 4K60p HEVC).

Repair effort: Medium to high. Tools can often rescue the healthy parts before and after the gap and render the gap as a freeze frame or a skip.

Damage type 5: Total loss (≈2% of all cases)

The file is 90% garbage. Common after severe hardware failure or NAND corruption. Even specialized tools often can’t do anything here.

Repair effort: Very high, often unsuccessful. A recovery specialist with hardware forensics (e.g. Aeroquartet, a few thousand euros) might still have a chance here.

Which tools exist — and what’s each one good for?

Here’s the honest tool hierarchy, ordered by the severity of damage each one can still handle.

Tier 1: VLC repair mode (free)

VLC has a built-in repair attempt — when you open a broken MP4 it asks: “Rebuild index?” For simple damage (container header missing, intact mdat) that works. Success rate: ~30%.

Open VLC → File → Open Advanced File → select MP4 → confirm index repair

Good for: container header missing, file otherwise intact. Not good for: everything else.

Tier 2: ffmpeg with error detection (free)

ffmpeg is the Swiss Army knife of video processing. With -err_detect ignore_err you can skip damaged packets.

ffmpeg -err_detect ignore_err -i kaputt.mp4 -c copy repariert.mp4

Success rate: ~40% for light damage, ~5% for a missing moov atom (ffmpeg gives up immediately when the container header is missing).

Good for: frame gaps, light codec-stream corruption. Not good for: moov header loss — see Tier 3.

Tier 3: untrunc-anthwlock (free, open source)

Specialized in the classic “moov missing” case. Needs a reference recording from the same camera.

untrunc -n -s referenz.mp4 kaputt.mp4

The -s flag (skip unknown sequences) is often needed — otherwise untrunc bails on Sony iPCM audio.

Success rate: ~75% with a reference, ~30% without.

Good for: moov header loss with an available reference. Not good for: audio-drift correction (untrunc often delivers out-of-sync sound), HEVC 10-bit (frequently blank picture), DiskDrill-recovered files with a corrupt uuid.

More details: untrunc and ffmpeg — open-source repair and where it stops

Tier 4: Specialized pro tools

Here it gets commercial. Three classes can be distinguished:

(a) recover_mp4 (Grau GmbH, approx. 99 USD) — the professional gold standard for container repair. But it has no audio-sync correction and no modern UI. More for IT forensics people.

(b) Stellar Repair, Wondershare Repairit, Recoverit — the typical Windows recovery suites with 100 features, 99 of which you don’t need. UI-heavy, often subscription models. Low success rate on professional codecs like XAVC or HEVC 10-bit. See Stellar Repair alternative and Recoverit alternative.

(c) Haven — the tool we built at Haven. Specialized in modern codecs (HEVC, XAVC, ProRes), automatic audio-drift correction, reference matching. Native on Mac and Windows. Free analysis, payment only on a successful repair.

Tier 5: Concierge services

Aeroquartet Treasured (49–700+ USD depending on the damage, 48h turnaround) isn’t a software product but a human service with a diagnostic frontend. They receive your uploaded file and repair it manually. Suited to extreme cases where no automated tool can get through anymore — but expensive and slow. See Aeroquartet Treasured review.

Data-recovery labs (Ontrack, Kroll Ontrack, from 500 USD) — hardware forensics on destroyed cards. Only worth it when the memory card itself is defective, not just the file.

Which strategy for which device?

Every recording device has its own container quirks. We’ve written detailed guides per device — here are the quick links:

• Repair GoPro video — battery drop, thermal shutdown, RECOVERY mode
• Repair Sony video — FX3, A7 series, XAVC-I, DiskDrill recovery
• Repair DJI video — drone crash, RTH mode, D-Log
• Repair Canon video — CFexpress buffer underrun, CLOG3
• Repair iPhone video — iCloud sync, ProRes, Cinematic mode

And by file format:

• Repair MP4 — ISO BMFF, the generic case
• Repair MOV — Apple QuickTime, ProRes, DNxHR
• Repair HEVC — H.265, 10-bit, HDR, Dolby Vision

What you should never do

Three common mistakes that destroy the remains of broken videos:

1. Working directly off the SD card. If you don’t copy the broken file to your hard drive first, every other write risks overwriting card sectors that hold repairable remains. Always: copy the original, lock the original away, work on a copy.

2. Reformatting the card “because it’s not working anyway.” Even when the file is broken, the bytes are often still on the card. A quick format only marks the index as empty — the data is there until it gets overwritten. Recoverable with recovery tools like PhotoRec or DiskDrill — see Repair DiskDrill-recovered video.

3. Opening the file on your phone. iOS and Android have extremely strict decoders. If you share a broken file on the phone (e.g. via AirDrop or WhatsApp), it often gets transcoded on the fly — and you lose repair options. Mac/PC first, then see what’s possible.

When is what worth it?

An honest decision matrix:

Situation	Strategy
File from phone/camera, simple damage	Try VLC or ffmpeg, takes 2 minutes
Pro recording, moov missing, you have a reference	Try untrunc — often works, but check for audio drift
Pro recording, audio drift after untrunc	Haven or recover_mp4
HEVC 10-bit, Cinematic mode, ProRes, XAVC	Haven (untrunc often fails on codec specifics)
DiskDrill-recovered, uuid header corrupt	Haven (reference matching compensates)
Total loss, all tools fail	Aeroquartet Treasured or a data-recovery lab

FAQ

Check the most common questions at the end of this article — they cover most of the edge cases.

What Haven does differently

We built Haven because none of the existing tools are truly good for modern professional codecs (HEVC 10-bit from iPhone Cinematic, XAVC-I from the FX3, D-Log from DJI). untrunc delivers audio drift. Stellar and Recoverit have high success rates only on simple H.264 files. Aeroquartet is slow and expensive.

Haven combines untrunc’s container-reconstruction strength with a purpose-built audio-drift correction, NAL-unit analysis for modern HEVC profiles, and a reference-matching strategy that also works on DiskDrill-recovered files. You see and hear the result before you pay. If it doesn’t work, it costs nothing.

Run a free Haven analysis →