I used "binwalk" to extract an image file and I got what I needed as a directory hierarchy. So I made my changes and now I want to repack it and get the .img file back out of it. Is there a solution?
I found a solution to accomplish this, I used imgRePacker_203 to get my image extracted.
If you could not find imgRePacker_203 online, then I have created a Git repo on my Github account and I included that tool with many other tools related to work with .img files. Also there is a very useful video on which you can get all links here:
https://github.com/AhmadVakil/Image-file-tools
https://www.youtube.com/watch?v=3zm91DfdkIo
Note: This solution is worked with ALLWINNER, and Whatsminer image that upgrade or downgrade the firmware of ASIC miner's control board. Hope you find it useful for other problems and extracting other images.