How to make PNG video render into 10bit h.264 matroska/avi file?
You can use

ffmpeg -i %04d.png -i audio.wav -c:v libx264 -crf 0 -c:a copy output.mkv


where %04d.png represents the pattern for the image filenames. The % is a prefix indicating a numbering pattern is specified afterwards. 04 represents a 4 character pattern, padded with zeros as necessary. d indicates that the characters are numbers.

The particular filename pattern captured in %04d.png is

0001.png
0002.png
0003.png
...


If instead they are 

1.png
2.png
3.png
...
999.png
...
9999.png


you would supply %d.png i.e. no padding.

If it's

myimages_00001.png
myimages_00002.png
myimages_00003.png
...


you would use myimages_%05d.png