what video format is the least cpu intensive to play (Raspberry PI)

[ole_thor1]

I am trying to play home movies for a senior (no computer knowledge) on a raspberry pi 3 (details follow). I need to convert the videos to a format which requires the least CPU to play. It is part of a program that monitors the senior and reports to me if she falls down or forgets to go for meals and events at the nursing home. The movie playing is not the most important function, so it can't consume all the cpu to play the home movies.

Similar to WAV files vs MP3 for music, what video formats require the least cpu to decode and play?
Thanks,
Ole.

RaspBerry PI 3 specs:
SoC: Broadcom BCM2837
CPU: 4× ARM Cortex-A53, 1.2GHz
GPU: Broadcom VideoCore IV
RAM: 1GB LPDDR2 (900 MHz)
Networking: 10/100 Ethernet, 2.4GHz 802.11n wireless
Bluetooth: Bluetooth 4.1 Classic, Bluetooth Low Energy
Storage: microSD

[usually_quiet]

You should probably use H.264/AVC. The RPi comes with an H.264 license, and the VideoCore IV GPU is capable of 1080p High Profile H.264 decoding. Licenses for other supported codecs, for example MPEG-2, would need to be purchased.

[Ole_thor]

to usually_quiet:
thanks for your response. I will convert a video to H264 and try it out on the pi.
Ole.

[jagabo]

Yes, h.264 is best for the RPi. Avoid h.265 as it doesn't have a hardware h.265 decoder and has to resort to CPU decoding. MPEG 2 and WMV require separate licenses (though only about US$5). MPEG4 PART 2 (Divx/Xvid) don't offer as good compression as h.264 (though they may encode faster if you don't have a GPU encoder or high core count CPU).

[Ole_thor]

jagabo and usually_quiet:
thanks for your advice. using H264 for the videos and the system is running at 1% cpu used to play the videos.
PERFECT!
thanks, Ole.