China DOS Union

There is an ISO file of a bootable CD. When opened with ultraISO, it shows that it is a bootable CD.
I want to extract the boot file. I click "Boot CD" -> "Save Boot File", and the result is that a 2k - size bif file is output. I have tried several different bootable CDs, and it is all like this.

And if I click "Make Floppy Image File" or "Make Hard Disk Image File", the generated is an IMA file with the size of the boot disk, which can be modified with WINIMAGE.

So please tell the friends who know how to extract the boot.IMA file from the bootable CD! Thank you!

The problem is found. Those several CDs are all boot disks of WINXP. Later, I found a self - made ISO file, saved the boot file as bif, and changed the extension to IMA, then it can be modified with WINIMAGE.