Recover Corrupted XAVC-S Files

XAVC-S isn't one camera — it's the codec and container Sony writes across almost its entire range: the Alpha mirrorless line (A7, A7S, A7R, A1, A9), the ZV vlogging cameras, the RX compacts, and the Cinema Line bodies (FX30, FX3, FX6) when they're set to XAVC S. If one of those recordings stopped before the camera finished writing the file, the picture and sound are almost always still on the card. What's missing is the small piece of data that tells a player where everything is.

This page is about the XAVC-S format. For a specific body, the camera guides at the bottom go deeper.

What XAVC-S actually is

• XAVC S — H.264 (AVC), Long-GOP, inside an MP4 container. The everyday Sony recording format.
• XAVC S-I — the same H.264, but All-Intra (every frame is a full keyframe). Bigger files, easier edits. Still MP4.
• XAVC HS — a different codec: H.265 / HEVC. If your file is XAVC HS, see Recover HEVC files.

Audio is LPCM. The index that ties the video frames and audio together — the MP4 moov atom — is written only at the moment recording stops cleanly.

What's in the file when it breaks

[ftyp]   ← MP4 + XAVC declaration, intact
[mdat]   ← all your H.264 frames + LPCM audio, interleaved
[????]   ← the moov index that should be here is missing

The frames are there. The map is gone. Rebuilding that map is the whole job.

Why XAVC-S recordings corrupt

The cause is almost never the codec — it's the recording being cut off before a clean stop:

• Battery dies mid-take.
• Card pulled before the write finishes — SD on the Alphas, CFexpress Type A on the A1 / A7S III / FX line.
• Thermal cutoff on long 4K takes.
• Card fills mid-recording.
• Power loss on a rig running off a dummy battery or USB-PD.

Every one of these leaves the same fingerprint: a healthy-looking .mp4 that no player will open.

What you can try first

1. Sony Catalyst Browse (free). Sony's own tool understands its XAVC variants and sometimes opens a file that QuickTime won't.
2. untrunc (open-source). Built for exactly this missing-index failure. It needs a healthy reference clip from the same camera in the same mode.
3. ffprobe. If FFmpeg reports stream info, the file is more recoverable than average.
4. Resolve or Premiere directly — both are more permissive about XAVC than QuickTime. A 30-second test costs nothing.

Always work on a copy of the file.

How our recovery handles XAVC-S

• No reference clip required. Codec parameters are read from the first valid keyframe in mdat.
• XAVC S and XAVC S-I both. H.264 Long-GOP and All-Intra are detected from the frame data — you don't have to tell us which.
• co64 for files over 4 GB. Long 4K takes routinely cross 4 GB; 64-bit chunk offsets are the default, so the second half of a large file doesn't silently break (the failure mode of tools stuck on 32-bit stco).
• LPCM audio handled correctly. Sample rate, channel layout, and byte order are read from the actual data, not assumed.
• Picture profile is preserved. S-Log3, S-Cinetone, and HLG live in the codec data, so the rebuilt file inherits them — S-Log3 footage comes back as S-Log3.
• Any Sony body. Because the recovery works at the format level, it doesn't care whether an A7 IV, a ZV-E1, an RX100, or an FX3 wrote the file.

What you do

1. Upload the XAVC-S file. Up to 50 GB.
2. About a minute later, a free 5-second preview.
3. Pay only if it works. Adjust the settings or escalate to a human if it doesn't.

FAQ

What's the difference between XAVC S, XAVC S-I and XAVC HS? XAVC S and XAVC S-I are both H.264 (Long-GOP and All-Intra respectively) in an MP4 container. XAVC HS is H.265 / HEVC — a different codec. We recover all three; if yours is HS, the HEVC guide is the closer match.

Which Sony cameras does this cover? Any that record XAVC-S — the Alpha mirrorless line (A7, A7S, A7R, A1, A9), the ZV vlogging cameras, the RX compacts, and the Cinema Line (FX30 / FX3 / FX6) in XAVC S modes.

Do I need a healthy reference clip? No. The structural rebuild reads everything it needs from the broken file's own frames. A reference only helps in unusual cases, and the diagnostic on upload will tell you if yours is one.

Will S-Log3 / S-Cinetone come back correctly? Yes. The colour profile is part of the codec data and is carried through untouched.

My file is over 4 GB. That's the normal case for 4K, and it's handled by default with 64-bit offsets. File size isn't the problem; a missing index is.

It plays for a second and then freezes. That's a different failure mode — mid-file damage rather than a missing index. Often still recoverable, sometimes by salvaging the intact section. The free diagnostic tells us which case you're in.

Is my footage safe? The file sits on a server in France, is auto-deleted after 48 hours, and is never used to train anything or shared. Privacy policy.

Related

• Sony FX3 XAVC corrupted — the camera-specific guide for the Cinema Line
• Sony A7S III corrupted MOV — Alpha-specific guide
• Recover HEVC / H.265 files — for XAVC HS footage
• What "MOOV atom not found" means
• How our recovery engine works

Upload your XAVC-S file →