On Linux, you don't need a special program to do this. Take a look at the instructions here:
https://unix.stackexchange.com/a/316407
(Replace "file.iso" in the example with "sd.raw")
Then just open the directory that you mounted the SD card image at (in the example, "/mnt/dir").
The SD card images used by Dolphin don't have partitions, so ignore the part of the instructions that are for hard drive images with partitions.
https://unix.stackexchange.com/a/316407
(Replace "file.iso" in the example with "sd.raw")
Then just open the directory that you mounted the SD card image at (in the example, "/mnt/dir").
The SD card images used by Dolphin don't have partitions, so ignore the part of the instructions that are for hard drive images with partitions.