Hey all,
Im trying to find a better file compression utility, that REALLY compresses multiple files down real well. the drop stuff/ zip app that comes with OSX 10.4 isint compressing down as much as I would like. Does anyone know of anything better? thanks for any info
Comments
Hey all,
Im trying to find a better file compression utility, that REALLY compresses multiple files down real well. the drop stuff/ zip app that comes with OSX 10.4 isint compressing down as much as I would like. Does anyone know of anything better? thanks for any info
As a side note, compressed formats such as jpeg, mpeg, mp3 etc, do not compress much further under any scheme.
-t
Not necessarily. RAR and LZMA (7z) surpass it in some cases.
Yeah that's true as shown here:
http://farrokhi.net/blog/archives/000409.html
I find that rar is quite slow though and it seems to make the system really sluggish after decompressing large files.
Having said that, it has built in ways to split files and it has a really good recovery mechanism for broken archives. Plus there are programs that allow you to view images stored inside rar archives without decompressing.
So definitely a format to consider. More often than not, I use dmg these days because decompression happens on the fly. I just wish it used bzip2 or similar instead of LZW (I think) by default.
UDRW - UDIF read/write image
UDRO - UDIF read-only image
UDCO - UDIF ADC-compressed image
UDZO - UDIF zlib-compressed image
UDBZ - UDIF bzip2-compressed image (OS X 10.4+ only)
UFBI - UDIF entire image with MD5 checksum
UDRo - UDIF read-only (obsolete format)
UDCo - UDIF compressed (obsolete format)
UDTO - DVD/CD-R master for export
UDxx - UDIF stub image
UDSP - SPARSE (grows with content)
RdWr - NDIF read/write image (deprecated)
Rdxx - NDIF read-only image (Disk Copy 6.3.3 format)
ROCo - NDIF compressed image (deprecated)
Rken - NDIF compressed (obsolete format)
DC42 - Disk Copy 4.2 image
As of Tiger, you can use bzip2 with DMG.
UDRW - UDIF read/write image
UDRO - UDIF read-only image
UDCO - UDIF ADC-compressed image
UDZO - UDIF zlib-compressed image
UDBZ - UDIF bzip2-compressed image (OS X 10.4+ only)
UFBI - UDIF entire image with MD5 checksum
UDRo - UDIF read-only (obsolete format)
UDCo - UDIF compressed (obsolete format)
UDTO - DVD/CD-R master for export
UDxx - UDIF stub image
UDSP - SPARSE (grows with content)
RdWr - NDIF read/write image (deprecated)
Rdxx - NDIF read-only image (Disk Copy 6.3.3 format)
ROCo - NDIF compressed image (deprecated)
Rken - NDIF compressed (obsolete format)
DC42 - Disk Copy 4.2 image
Ah, I don't know why they don't update Disk Utility to allow you to select the option through the GUI, I always forget the hdiutil commands. I'll probably stick with the default for compatibility but it's good to know the option's there.
Hey all,
Im trying to find a better file compression utility, that REALLY compresses multiple files down real well. the drop stuff/ zip app that comes with OSX 10.4 isint compressing down as much as I would like. Does anyone know of anything better? thanks for any info
If you don't mind lossy compression, 'rm' is unbeatable.
If you don't mind lossy compression, 'rm' is unbeatable.
But the compression artifacts are horrible!!
what I want is a compression utility that compresses (really well) multiple file types .. into one small archived file for emailing purposes.
File types that aren't already compressed?
File types that aren't already compressed?
No, that are allready compressed, optimized-whatever you want to call it.. I just want to combine them into one nicely zipped package for emailing use.
No, that are allready compressed, optimized-whatever you want to call it.. I just want to combine them into one nicely zipped package for emailing use.
You do realize that already compressed files won't compress too much anymore, there is only a limited amount of data that can be removed, without loss. I think all the options presented here would do what you want. I would be more worried about the file format, instead of wanting to run around the web to find right de-compressor, I would rather receive a packet in known format, may it be little bigger. If your problem is quota limit in receivers email box, have you considered that there are many more convenient ways to transfer data than emailing it. Many compressors can also make many small archives, that can be sent separately, so that receiver can empty his/her inbox before sending next chunk.
bzip2 is indeed the best format.
BZIP2 is the best compression format when considering both speed and compression ratio. It tends to be within five to ten percent of much more costly statistical compression methods.
Plus, I'm not sure if it has been done yet, but BZIP2 uses a transform algorithm which means that it can be easily optimized for SIMD and multi-core chips. I can't think on any other compression algorithm that so easily allows for this. It won't be long before BZIP2 is the fastest compression algorithm, if it isn't already.