Photoshop-less way using ffmpeg to convert an RGB file created by xxd without a header to a PNG

As per Convert raw RGB32 file to JPEG or PNG using FFmpeg, here’s how to convert a .raw file of RGB values without a header to a PNG

xxd -l 49284 -u -r -p \
2020-and-2019-roland-flickr-imagemagick-average-colours.txt\
2020-and-2019-roland-flickr-imagemagick-average-colours.raw
ffmpeg -f rawvideo -pixel_format rgb24 -video_size 222x222 \
-i 2020-and-2019-roland-flickr-imagemagick-average-colours.raw \
-frames:v 1 output.png
 mv output.png ffmpeg-2020-and-2019-roland-flick-average-colour-output.png

Untested but perhaps adding a header like the following will work (as per Converting raw images without headers (and then convert the ppm file to PNG using imagemagick)?
```
{ printf "P6\n%d %d\n255\n" WIDTH HEIGHT ; cat YOURFILE; } > result.ppm
```
See Average colour according to imagemagick resize of my flickr photos Jan 1, 2019 - Dec 31, 2020 where I document how to do it with Photoshop and the xxd command to get the raw file