tochd

Convert game ISO and archives to CD CHD for emulation.

• Author: Tuncay D.
• Source: https://github.com/thingsiplay/tochd
• Releases: https://github.com/thingsiplay/tochd/releases
• Update Notes: CHANGES
• License: MIT License

What is this program for and what are CHD files?

Automation script written in Python as a frontend to 7z and chdman for converting CD formats into CD CHD.

When you are playing CD based games on RetroArch or possibly on any emulator which supports CHD files, then you might want to convert your ISO and CUE+BIN or GDI files into the CHD format. It has the advantage good compression and produces a single file for each CD. This saves a lot of space and makes organization easier.

To achieve this, the separate program chdman from the MAME tools is invoked, which introduced the CHD format in the first place. Often you need to extract those various CD formats from archives such as .7z or .zip files too. The program 7z is used to extract those files, before handing them over for conversion.

Requirements

The script is written in Python 3.10 for Linux. No other Python module is required. The following external applications are required to run the script:

7z
chdman

On my Manjaro system, they are available in the packages: p7zip mame-tools

Installation

No special installation setup is required, other than the above base requirements. Run the script from any directory you want. Give it the executable bit, rename the script to exclude file extension and put it into a folder that is in the systems $PATH . An installation script "install.sh" is provided, but not required.

If you have an older Python version, then you might want to check the binary release package, which bundles up the script and Python interpreter to create a standalone executable.

Optional: Makefile and PyInstaller (you can ignore this part)

The included "Makefile" is to build the package with the standalone binary. It will create a venv, update stuff in it and run PyInstaller from it. If the process fails, then maybe the system package mpdecimal could be required. At least this was required on my Manjaro system.

Usage

usage: tochd [OPTIONS] [FILE ...]

usage: tochd [-h] [--version] [--list-examples] [--list-formats]
             [--list-programs] [--7z CMD] [--chdman CMD] [-d DIR] [-R] [-p]
             [-t NUM] [-c NUM] [-f] [-q] [-E] [-X] [-]
             [file ...]

This is a commandline application without a graphical interface. The most basic operation is to give it a filename, a list of files or directories to work on. The default behaviour is to convert .iso and .cue+bin and .gdi files to .chd files with same basename in their original folders. Archives such as .7z and .zip are extracted and searched for files to convert. The progress information from 7z and chdman are printed to stdout.

How to use the commandline options

Options start with a dash and everything else is file or folder. In example tochd . will search current working directory for files to convert. Using the option -X like this tochd -X . will just list files without processing them. The option -d DIR specifies a directory to output the created .chd files into. In example tochd -q -d ~/chd ~/Downloads will process all files it can find in the "Downloads" directory and save the resulting .chd files in a folder named "chd" in the users home folder. The -q option means "quiet" and will hide progress information from 7z and chdman, but still print out the current job information from the script itself.

You can also specify filenames directly or use shell globbing * in example to give a list of files over. Usually that is not a problem, but if any filename starts with a dash -, then the filename would be interpreted as an option. But you can use the double dash -- to indicate that anything following the double dash is a filename, regardless what the first character is. In example tochd -- *.7z will process all .7z files in current directory.

Use tochd --help to list all options and their brief description.

Examples

$ tochd --help
$ tochd .
$ tochd -X .
$ tochd ~/Downloads
$ tochd -- *.7z
$ tochd -pfq ~/Downloads | grep 'Completed:' | grep -Eo '/.+$'
$ ls -1 | tochd -

Example output

The following is an output from some files I used to test the program. The failing jobs are supposed to fail, for one or another reason. "Completed" jobs are files that are successfully created. "Failed" jobs point to the path that would have been created.

$ tochd -fq cue iso gdi unsupported .
Job 1     Started:	/home/tuncay/Downloads/cue/Vampire Savior (English v1.0).7z
Job 1   Completed:	/home/tuncay/Downloads/cue/Vampire Savior (English v1.0).chd
Job 2     Started:	/home/tuncay/Downloads/cue/3 x 3 Eyes - Sanjiyan Hensei (ACD, SCD)(JPN).zip
Job 2      Failed:	/home/tuncay/Downloads/cue/3 x 3 Eyes - Sanjiyan Hensei (ACD, SCD)(JPN).chd
Job 3     Started:	/home/tuncay/Downloads/cue/Simpsons Wrestling, The (USA).7z
Job 3   Completed:	/home/tuncay/Downloads/cue/Simpsons Wrestling, The (USA).chd
Job 4     Started:	/home/tuncay/Downloads/cue/Shining Wisdom (USA) (DW0355).rar
Job 4   Completed:	/home/tuncay/Downloads/cue/Shining Wisdom (USA) (DW0355).chd
Job 5     Started:	/home/tuncay/Downloads/iso/Parodius_Portable_JPN_PSP-Caravan.iso
Job 5   Completed:	/home/tuncay/Downloads/iso/Parodius_Portable_JPN_PSP-Caravan.chd
Job 6     Started:	/home/tuncay/Downloads/iso/Bust_A_Move_Deluxe_USA_PSP-pSyPSP.iso
Job 6   Completed:	/home/tuncay/Downloads/iso/Bust_A_Move_Deluxe_USA_PSP-pSyPSP.chd
Job 7     Started:	/home/tuncay/Downloads/gdi/[GDI] Metal Slug 6.7z
Job 7   Completed:	/home/tuncay/Downloads/gdi/[GDI] Metal Slug 6.chd
Job 8     Started:	/home/tuncay/Downloads/gdi/[GDI] Virtua Striker 2 (US).7z
Job 8   Completed:	/home/tuncay/Downloads/gdi/[GDI] Virtua Striker 2 (US).chd
Job 9     Started:	/home/tuncay/Downloads/gdi/GigaWing 2.zip
Job 9   Completed:	/home/tuncay/Downloads/gdi/GigaWing 2.chd
Job 10    Started:	/home/tuncay/Downloads/unsupported/Dragon_Ball_Z_Shin_Budokai_USA_PSP-DMU.rar
Job 10     Failed:	/home/tuncay/Downloads/unsupported/Dragon_Ball_Z_Shin_Budokai_USA_PSP-DMU.chd
Job 11    Started:	/home/tuncay/Downloads/unsupported/ActRaiser 2 (USA) (MSU1) [Hack by Conn & Kurrono v4].7z
Job 11     Failed:	/home/tuncay/Downloads/unsupported/ActRaiser 2 (USA) (MSU1) [Hack by Conn & Kurrono v4].chd
Job 12    Started:	/home/tuncay/Downloads/missingfiles.gdi
Job 12     Failed:	/home/tuncay/Downloads/missingfiles.chd

Cancel jobs

At default Ctrl+c in the terminal will abort current job and start next one. Temporary folders and files are removed automatically, but it can't hurt to check manually for confirmation. Temporary folders are hidden starting with a dot in name.

Multiprocessing support

At default all files are processed sequential, only one at a time. Use option -p (short for --parallel) to activate multithreading with 2 threads. This enables the processing of multiple jobs at the same time. Set number of max threads with option -t (short for --threads).

Drawbacks with multiprocessing / parallel option

• live progress bars and stderror messages of invoked processes from 7z and chdman cannot be provided anymore, as they would have been overlapping on the terminal, but stdout messages such as statistics are still output
• user input won't be allowed and is automated as much as possible, because overlapping messages could lead to stuck on waiting for input and losing the context to what file it belongs to are potential problems

Additional notes, workarounds and quirks

If you forcefully terminate the script while working, then unfinished files and especially temporary folders cannot be removed anymore. These files and folders can take up huge amount of space! Temporary folders are hidden starting with a dot "." in the name, followed by the name of archive and some random characters added. Make sure these files are deleted, in case you forcefully terminate the script.

Some archives contain multiple folders, each with ISO files of same name. These are usually intended to copy and overwrite files in a main folder as a meaning of patching. However, the script has no understanding and knowledge about this and would try to convert each .iso file on it's own. As a workaround all .iso files in the archive are ignored when a sheet type such as CUE or GDI files are found.