If you need a CHD after editing:
chdman createcd -i "modified.iso" -o "modified.chd"
If you are managing a large ROM collection and need to repack multiple games, batch processing is essential. convert chd to iso repack
genisoimage -R -J -l -udf -iso-level 3 \
-o final_repacked.iso \
-V "GAME_NAME" \
-allow-leading-dots \
-no-pad \
/tmp/repack_contents/
Flag explanations:
Most fan-translation patches (XDelta, IPS, or PPF) are designed for ISO or BIN/CUE files. Applying a translation patch directly to a CHD is impossible without decompression. If you need a CHD after editing: