Note: Use extracthd for hard drive/DVD images (like PS2/PSP) and extractcd for CD-based games (like PS1). 2. The Faster Method: Batch Conversion via Scripts
A GitHub-hosted tool that can manage and convert ROM formats for multiple platforms. Comparison: CHD vs. ISO
Double-click convert.bat . A command prompt window will open, and chdman will automatically loop through every CHD file in the folder, converting them back to their original uncompressed formats.
Download from a trusted emulation forum or GitHub repository. Launch the application. Set the mode to Decompress / Extract .
Right-click inside the folder, select , and choose Text Document . Open the text document and paste the following code: convert chd to iso better
Open a terminal in that folder and type: chdman extracthd -i "yourgame.chd" -o "yourgame.iso"
: Optical discs that utilize separate tracks for red-book audio data cannot exist natively as a single .iso file. Do not force them into an ISO extension, or the game will lose its music and likely crash. Keep them as BIN/CUE files.
What are you running? (Windows, macOS, Linux)
for %%i in (*.chd) do (chdman extractcd -i "%%i" -o "%%~ni.iso") Note: Use extracthd for hard drive/DVD images (like
Converting (Compressed Hunks of Data) back to is a common task for enthusiasts who need to modify game files, apply ROM hacks, or use emulators that don't yet support CHD's lossless compression. Why Convert CHD back to ISO? While CHD is superior for storage—often saving 20% to 70% of space—reverting to ISO is necessary if:
(Note: extractcd is used for CD-based games like PS1, while extractraw is often used for DVD-based games like PS2, though extractcd generally handles the cues/toc logic better).
Tools used to inject translations, custom textures, or cheats require uncompressed raw data.
Go to the official MAME dev website or a trusted emulation repository. Comparison: CHD vs
"Wait," Elias said, looking at the file size. "I thought the ISO would be smaller."
Click on the address bar at the top of the file explorer window.
If you have an entire folder of CHD files that you need to revert to ISO or BIN/CUE format, running commands one by one is inefficient. You can automate the process using a simple Windows batch script. Step-by-Step Batch Guide:
如果有很多个CHD文件需要转换，一个个手动修改文件名会非常繁琐。此时，你可以使用更高效的批处理命令，甚至实现一键拖拽转换。
If you only have one or two files to convert, you can use the command prompt: Copy your .chd file into the same folder as chdman.exe .
Because it is maintained by the same team that designed the CHD format, so it always supports the latest compression features and validates the integrity of the files.