)įinally, I suggest you have a look at these movies (no faking) showing how fast and how long it takes to decompress respectively a zip file and a dmg file. You have understood by now, I hate disk images and I hope more and more developers will use zip files in the future to distribute their softwares in order to save their users' precious time. Moreover, they have to go to the desktop in order to unmount the disk image. When using a non internet-enabled disk image, users have to copy the application into the Applications folder which takes much more time than moving it. While this is true, this is also very slow. Some may argue that disk images are nice for drag & dropping the software into the Applications folder. It's simple and efficient, so why not using it ? A convenient Create archive of '.' stands in the File menu of the Finder. Prior to Mac OS X 10.3, StuffIt Expander was bundled with Mac OS X. Since Mac OS X 10.3, zip file compression and decompression is natively supported. If you know such an exemple, please post a comment about it. Results may vary depending on application size and may be slightly different for a ten MB application but I can't see how a disk image could be either smaller or faster to decompress than a zip archive. Remove any file or folder from an archive, or even. Update Archives: Add new or updated files to existing archives. Yes, these are the ten operations required for an internet-enabled disk image to achieve the decompression! Zip decompression requires only two phases: decompressing the zip file and checking the downloaded files, thus it is 56 times faster. 7-zip and rar archives can also be protected. That's bad (not all Mac users have a broadband connection) but what is worse is the time to prepare the disk image, verify the disk image, mount the disk image, clean up, check the download files, prepare the disk image, mount the disk image, copy the disk image, unmount the disk image and clean up. Impressing, isn't it ? The size is almost twice bigger for the dmg although I used maximum compression (zlib level 9). those which copy their content, unmount and go to trash automatically. I'm talking here about internet-enabled disk images, i.e. I bundled a 1.9 MB application (Transmission) into both a zip file and a dmg file. I did an experiment that I think is rather representative.

My gripe against this practice is simple: it's very slow. This is not really surprising as this is Apple's recommended practice for software distribution. Most Cocoa developers use disk images (aka dmg) for distributing their softwares over the Internet.

Zip to dmg mac