How to make PNG video render into 10bit h.264 matroska/avi file? I'm not good with this stuff, so please dumb things down as much as humanly possible and assume that what I type is probably all i know about ffmpeg.

Okay so I rendered a 1080p video as thousands of 16 bit png images.

I want to take these images and create a 10 bit h.264 video file with either a matroska or avi container. I'll need to add in a .wav file as the sound without re-encoding as well. I'm guessing I can just use this command at any time to do so after its in mkv format in this example:
ffmpeg -i original.mkv -i audio.wav -c copy output.mkv

So this is what I have so far: Note I have no idea what the input for PNG images is so I just left it as "input" as you see below. When I do the command below on a normal video file it uses 8 bit. So I need to know the command to specify 10 bit.

ffmpeg -i input -c:v libx264 -preset veryslow -crf 0 output.mkv





(1) ffmpeg -i input.mkv -i audio.wav -c copy output.mkv 
(2) ffmpeg -i input.mkv -i audio.wav -acodec copy output.mkv
(3) ffmpeg -i input.mkv -i audio.wav -c:a copy output.mkv 
(4) ffmpeg -i input.mkv -i audio.wav -vcodec libx264 -acodec copy output.mkv 


Which of these 4 is the best to use if I JUST want to combine video with audio without re-encoding? or is there an even better one to use?I was told -acodec copy is necessary to ensure it doesn't re-encode, but others have told me differently. should I use -acodec copy instead of -c:a copy?
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