Canon EOS 77D Mode D'emploi De Base page 153

Compression method

X IPB (Standard)
Compresses multiple frames at a time efficiently for recording.
Xv IPB (Light)
Since the movie is recorded at a low bit rate for playback on various
devices, the file size will be smaller than with IPB (Standard).
Therefore, you can shoot longer than with IPB (Standard).
Do not hold the camera in the same position for long periods of time.
Even if the camera does not feel too hot, prolonged contact with the same
body part may cause skin redness or blistering due to low-temperature
contact burns. Using a tripod is recommended for people with circulation
problems or very sensitive skin, or when using the camera in very hot
places.
3 Setting the Movie Recording Size
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