This a nice lossless way to compress a CD\DVD image file in order to get a better compression ratio. First you need a application called ECM. You can get that here:
Once you have downloaded and extracted the application to a folder on your machine you will need to do the following to compress you image file:
- Open a Command Prompt
- Browse to the location of the unzipped files you downloaded earlier (eg: c:\ecm\)
- To compress use the following syntax: ecm imagefile ecmfile (eg: ecm c:\iso\image.iso c:\iso\image.iso.ecm)
- To uncompress use the following syntax: unecm ecmfile imagefile (eg: unecm c:\iso\image.iso.ecm c:\iso\image.iso)
Once this process has completed, you can then use your favourite compression application to get the maximum compression out of the ecm file that you created.
In other words, when doing this you can expect an increase in compression of around 15% on average. (eg: 650MB iso file may compress to 600MB and a 700MB bin file may compress to 400MB)