XAVC S
Also known as: XAVC S 4K, XAVC S HD, Sony XAVC
Sony's recording format for consumer and prosumer cameras: H.264 video with audio, stored in an MP4 file. Used by Sony action cams, Alpha and ZV models.
Updated
What it means
XAVC S is the name Sony gives to the recording format on its consumer and prosumer cameras, including the FDR-X3000 and HDR-AS300 action cams and many Alpha and ZV models. Despite the brand name, it is not an exotic codec: the video is H.264 in long-GOP form, the audio is usually linear PCM, and everything is wrapped in a standard MP4 container.
Sony splits the family by resolution and compression. XAVC S HD covers 1080p, XAVC S 4K covers UHD, and newer cameras add XAVC S-I, an all-intra variant that is easier to edit but far larger. XAVC HS is a separate, newer format that switches to H.265.
How it works in practice
On the FDR-X3000, XAVC S 4K records at 100 or 60 Mbps and XAVC S HD at 50 Mbps, so a 64 GB card fills in roughly 80 minutes at the top 4K setting. Sony asks for a fast card for these modes, typically UHS-I U3 or V30 for 100 Mbps recording.
On most Sony cameras the clips land deep in the folder tree, usually PRIVATE/M4ROOT/CLIP, with names like C0001.MP4 and a small XML sidecar such as C0001M01.XML holding camera metadata. The MP4 is the only file you need for editing. Higher-end bodies can record XAVC S in 10-bit 4:2:2, which grades beautifully but is harder for laptops to decode.
What to watch out for
Because the files hide inside PRIVATE, people sometimes copy only the DCIM folder and leave every video behind, thinking the card held only photos. Check M4ROOT before you format.
Do not assume XAVC S and XAVC HS are interchangeable either. HS footage is HEVC and may stutter on older machines that play XAVC S without complaint. The 10-bit 4:2:2 H.264 variant is the trickiest of all, since many computers and phones have no hardware decoder for it and fall back to slow software playback. If an editor chokes, convert to a standard 8-bit 4:2:0 file or use proxies. Finally, flat log profiles like S-Log need grading before the footage looks normal.
How RawClip handles it
Standard XAVC S HD and 4K clips are H.264 in an MP4 file, which RawClip accepts, so upload the C0001.MP4 files straight from the card and skip the XML sidecars. Sony footage can sit in the same order as GoPro, DJI or phone clips. If you shot S-Log, apply your grade first, since RawClip does not apply LUTs or color grades.