Wiki/wiki-rtd/docs/wiki_development/functions/compression.md

Compress games

Compression shell script

The shell script:

functions/compression.sh

With in the script there are several functions.

compress_game()

Description:

  # Function for compressing one or more files to .chd format
  # USAGE: compress_game $format $full_path_to_input_file

find_compatible_compression_format()

Description:

  # This function will determine what compression format, if any, the file and system are compatible with from the compression_targets.cfg
  # USAGE: find_compatible_compression_format "$file"

validate_for_chd()

Description:

  # Function for validating chd compression candidates, and compresses if validation passes. Supports .cue, .iso and .gdi formats ONLY
  # USAGE: validate_for_chd $input_file

cli_compress_single_game()

Description:

  # This function will compress a single file passed from the CLI arguments
  # USAGE: cli_compress_single_game $full_file_path

cli_compress_all_games()

Description:

  # This function will compress a all games passed from the CLI arguments

Compression targets reference list

The reference list:

emu-configs/defaults/retrodeck/reference_lists/reference_lists/compression_targets.cfg

The config is populated with compression formats with within [] and what es-de folders that are targeted for the format compression. Each system can only have one format.

Each new system has to be on a new line under it's compression format.

This is used by the find_compatible_compression_format() function above.

Example

[chd]
3do
amigacd32
[rvz]
gc
[zip]
atari2600

• 3do and amigcd32 is compressed to chd
• gc is compressed to rvz
• atari2600 is compressed to zip

How to add new system to compress

1. Make sure the emulator supports the compression format and RetroDECK is using that version that supports it.
2. Add the es-de folder name to compression_targets.cfg to the compression format it supports.