H.265 (HEVC)
Also known as: HEVC, H.265, High Efficiency Video Coding
The successor to H.264, also called HEVC. It keeps similar quality at roughly half the bitrate and is required for 5.3K, top frame rates and 10-bit recording.
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What it means
H.265, or HEVC (High Efficiency Video Coding), is the codec that followed H.264, standardized in 2013. It uses larger, more flexible coding blocks of up to 64 by 64 pixels and smarter prediction, which lets it deliver similar picture quality at roughly half the data rate, or noticeably better quality at the same rate.
For action cameras that efficiency is what unlocks the top modes. 5.3K, 4K at 120 fps and 10-bit color all lean on HEVC, and most current GoPro, DJI and Insta360 cameras either default to it or offer it as the high efficiency option. iPhones have recorded HEVC by default for years.
How it works in practice
GoPro marks HEVC clips with a GX prefix, as in GX010087.MP4, while H.264 clips start with GH. DJI cameras list it simply as H.265 in the menu. A 4K clip recorded at 100 Mbps in HEVC holds noticeably more fine detail in foliage and water than the same Bitrate in H.264.
HEVC also carries 10-bit depth comfortably, which is why log profiles such as D-Log M and GP-Log are recorded in it. If you plan to grade, HEVC 10-bit is the setting to use. Recent phones and computers decode it in hardware, so playback is smooth on modern gear, including Apple silicon Macs and most Windows machines with a recent graphics chip.
What to watch out for
The main pain point is older hardware. A computer without an HEVC hardware decoder will stutter badly on 4K or 5.3K clips, and Windows may need the HEVC Video Extensions from the Microsoft Store before it plays the files at all. Test one clip before an editing session, or plan on proxies.
Some older TVs, web tools and social apps also handle HEVC poorly, or quietly re-encode it. That matters for delivery, not for recording: shoot in HEVC for quality, then export to whatever the destination needs. Do not convert all your footage to H.264 up front just to make it play; that adds a generation of loss and doubles the storage.
How RawClip handles it
RawClip accepts HEVC uploads directly, including the 4K and 5.3K modes that depend on it and high frame rates up to 120 fps. There is no need to convert GX files or iPhone High Efficiency clips first. Upload them as they came off the camera, mixed with H.264 footage if you have it, and the highlight comes back as an MP4 in 4K and 1080p.