Data Compression/Executable Compression/ECM file on Linux
How to compress or decompress an ECM file on GNU/Linux?
Description[edit | edit source]
The ECM format allows you to reduce the size of a typical CD image file (ISO, BIN, CDI, NRG, CCD, or any other format that uses raw sectors). It works by eliminating the Error Correction/Detection Codes (ECC/EDC) from each sector whenever possible. The encoder automatically adjusts to different sector types and automatically skips any headers it encounters. Since the data skipped is nearly impossible to compress with traditional tools, the resulting ECM file will compress far better than the raw CD image.
ECM on Linux[edit | edit source]
Install the "ecm" package, it is available in Debian repositories:
https://packages.debian.org/stretch/ecm
apt install "ecm"
Compress[edit | edit source]
use "ecm-compress" command
EXAMPLES
ecm-compress foo.bin strips the ECC/EDC data from the foo.bin CD image and save the resulting file as foo.bin.ecm
ecm-compress foo.img foobar strips the ECC/EDC data from the foo.img CD image and save the resulting file as foobar
run "man ecm-compress" for more information
De-compress[edit | edit source]
use "ecm-uncompress" command
EXAMPLES
ecm-uncompress foo.bin.ecm regenerate the ECC/EDC data from foo.bin.ecm and save the resulting CD image as foo.bin
ecm-uncompress foo.img.ecm foobar regenerate the ECC/EDC data from foo.img.ecm and save the resulting CD image as foobar
run "man ecm-uncompress" for more information