Sony XAVC Files Explained: Where the Video Is, What C0001 Means, and S vs HS vs S-I
Sony cameras put video in a different folder from photos, add an XML file to every clip and can record a second, smaller copy. Here is the card layout, what XAVC S, XAVC HS and XAVC S-I mean in practice, and the in-camera settings that stop two Sony bodies producing the same file names.
On a Sony mirrorless camera, photos go in DCIM but video does not. Clips are in PRIVATE/M4ROOT/CLIP, named C0001.MP4, C0002.MP4 and so on, each with an XML file beside it. Proxy copies, if you turned them on, are in PRIVATE/M4ROOT/SUB. Copy only DCIM and you have the photos and none of the video. Copy the whole card, every time.
The card layout
DCIM/
100MSDCF/
DSC00001.JPG
DSC00001.ARW
PRIVATE/
M4ROOT/
CLIP/
C0001.MP4
C0001M01.XML
SUB/
C0001S03.MP4
THMBNL/
GENERAL/
MEDIAPRO.XMLSony's help guide for the A7 IV shows the same split: DCIM for still images, CLIP for movies and SUB for proxy movies.
| Item | What it is | Keep it? |
|---|---|---|
CLIP/C0001.MP4 | The video | Always |
CLIP/C0001M01.XML | Metadata for that clip, read by Sony's own software | Yes, it is tiny |
SUB/C0001S03.MP4 | Low-bitrate proxy copy | Optional: useful for editing on a laptop or sharing to a phone |
THMBNL, GENERAL | Thumbnails and other files the camera uses | Copy them with everything else |
MEDIAPRO.XML | The card's index of clips | Copy with everything else |
Do not tidy the card from the computer
Sony's help guide warns against editing, processing or deleting movie files on the card from a computer. Doing so can damage files or leave the camera's image database inconsistent. Copy everything off, check the copy, then format the card in the camera.
XAVC S, XAVC HS and XAVC S-I
All three are MP4 files. The difference is the codec and how it compresses:
| Format | Codec | Compression | In practice |
|---|---|---|---|
| XAVC S | H.264 | Long GOP: compresses across groups of frames | Plays almost anywhere. Bigger than HS at the same quality |
| XAVC HS | H.265 (HEVC) | Long GOP | Sony says higher quality than XAVC S at the same data volume. Needs a device or software that can decode HEVC |
| XAVC S-I | H.264 | Intra: each frame compressed on its own | Sony calls it more suitable for editing. Very large files |
Source: Sony's A7 IV help guide, checked October 2026.
How fast each one fills a card
Sony's own recordable-time table for the A7 IV on a 128 GB SD card, proxies off:
| Format and setting | Approximate time on 128 GB |
|---|---|
| XAVC HS 4K, 100 Mbps | 2 h 10 min |
| XAVC HS 4K, 45 Mbps | 4 h 30 min |
| XAVC S 4K, 150 Mbps | 1 h 30 min |
| XAVC S HD, 50 Mbps | 4 h 10 min |
| XAVC S-I 4K, 60p, 600 Mbps | 25 min |
| XAVC S-I HD, 60p, 222 Mbps | 1 h |
Sony notes these vary with the scene, because the camera uses a variable bitrate.
For travel, where you will carry every gigabyte home on cards and drives, XAVC HS is the efficient choice if your editor handles HEVC. XAVC S-I makes sense for short, deliberate shots you plan to grade, not for filming a whole day.
Proxies: worth turning on?
Sony's Proxy Recording records a second, small copy at the same time. On the A7 IV, the options are XAVC HS HD at 16 or 9 Mbps, or XAVC S HD (1280x720) at 6 Mbps. Proxies are not available at 120p or 100p.
Turn them on if you edit on a laptop that struggles with 4K HEVC, or want to send clips to a phone quickly. Note Sony's warning: deleting a clip in the camera deletes its proxy too, and you cannot delete one without the other in the camera.
File names: C0001 and how to stop clashes
By default, video files are C plus a four-digit number. Two Sony bodies on one trip will both produce C0001.MP4, and so will one body over two cards if numbering resets. Sony's own settings fix this at the source.
For video: File Settings
MENU, Shooting, File, File Settings. Sony's options, from the A7 IV help guide:
- File Number: Series keeps counting across cards; Reset starts again when you change the card. Use Series.
- File Name Format: Standard (
C0001), Title, Date + Title, or Title + Date. - Title Name Settings: up to 37 characters, letters, numbers and some symbols.
Set the title to the camera, for example A7IV_, and choose Date + Title. Every clip then carries the date and which body shot it, and two cameras can no longer produce the same name. Sony notes two limits: the format is locked to Standard on SDHC cards, and a card recorded with a custom title may not work properly in another device.
Once the counter reaches 9999, Sony says unused numbers are reused, which is another reason to put the date in the name.
For photos: File/Folder Settings
MENU, Shooting, File, File/Folder Settings. Set File Name replaces the first three characters of photo names, so DSC00001.JPG can become A7C00001.JPG on one body and A6700001.JPG on another. Folder Name can use a date form instead of 100MSDCF.
Which Sony bodies this applies to
The card layout and XAVC names are shared across Sony's current mirrorless line. Card slots differ, which matters for XAVC S-I's high bitrates:
| Body | Card slots | Weight |
|---|---|---|
| Sony A7 IV | CFexpress Type A / SD UHS-II, plus SD UHS-II | 658 g |
| Sony A7C II | SD UHS-II | 514 g |
| Sony A6700 | SD UHS-II | 493 g |
| Sony ZV-E10 II | SD UHS-II | 377 g |
| Sony FX30 | Two CFexpress Type A / SD UHS-II | 646 g |
Specs from the makers' published data, checked October 2026.
Copying a Sony card safely
- Copy the whole card,
PRIVATEincluded, into a new folder named for the date and the body. - Verify the copy against the card: verified copy vs drag and drop.
- Format in the camera.
Sony's free Catalyst Browse can preview XAVC clips, show metadata, copy to a drive and apply stabilisation using the camera's metadata. Keep the original clips if you want that stabilisation: a re-encoded copy may not carry the data it needs.
For a folder scheme that keeps Sony, drone, action camera and phone footage apart, see photo folder structure for multiple cameras. If you are importing on a Mac without Photos, see importing an SD card on a Mac without Photos.