Larger RAR file or smaller 7z file?

I’ll post this here because I would like to get some feedback from the users of our patched firmware.

To support the later flash chips the LiteOn flasher is now 5MB in size. The problem is that RAR only supports a 4MB dictionary. This means that it cannot use “solid” to compress these files. In the past each additional firmware only added about 20KB or so but now each firmware adds 820KB. You can do the maths, 3 firmwares is 2.4MB, as opposed to around 850KB.

The only alternative I can come up with is to use 7z, which has an almost infinite size selection for the dictionary and by selecting 8MB the file size is around 800KB. The other good thing about 7z is that it’s support for decompression by WinRAR and other programs, include some free ones.

My reason for this post is to get some feedback from you about which method you think I should use or perhaps some alternate method. I prefer using RAR files but the size is now a big disadvantage.

Suggest using smaller 7z , Winrar can support all this file.

Whilst 7z isn’t in such common use as Winrar it is easily obtained and you could always included a link to it on codeguys anyway.

So I say do it.

7z is fine, as [B]TimC[/B] said.


I’d also vote for 7zip. Also, there is an option to create self-extracting archives, so having installed 7zip isn’t even mandatory.

The latest beta version of 7zip btw has much better support for some RAR archives allowing to extract Samsung’s flash+firmware packages now. :cool:


I found PowerArchiver 2007, which gives me most of the shell features of WinRAR for 7z :slight_smile: but even with this app, it doesn’t seem like I can delete a file from a solid 7z archive. :frowning:


Is that a “solid” archive?
EDIT: Yes, it is :wink:

Why do the add, delete and update operations not work for some existing archives?

The current version of 7-Zip can’t execute some operations with .7z archives that have been created with the “solid” option switched on.
I wouldn’t expect 3rd party software to support 7z archives better than the original one.


Thanks Michael. They boast that their Ultra 7z compression is better than any other archiver.

PowerArchiver 2007 allows drag and drop add (file to file) to a solid 7z archive (rebuild the archive), which I use a lot with WinRAR. It’s actually a very nice app and still allows all of the shell WinRAR features to be used for RAR files. But I’m surprised it can’t unpack and repack to delete files, like WinRAR does with a solid archive. :confused:

PowerArchiver 2007 introduces a new Transparent Update feature for 7-Zip archives, which allows you to quickly add or remove files even if the archive is “Solid.”

It says this but I can’t find any way to delete a file from a 7z archive, even with this feature enabled and solid disabled. :confused:


What happens if you try the same with 7zip and non-solid archives?

I suspect that the inability to change the content of a solid 7z archive might be a flaw with the format itself :confused:

P.S.: suggest to move this thread to Gen Software :wink:

As much as it pains me, I have to say RAR.

I never liked RAR (mostly because of the company that makes it, not the format), and I very much like 7z. I make personal backups in 7z.

But right now, 7z’s support outside the Windows arena isn’t quite up to snuff. It’s growing, and growing quickly, so maybe in under 6 months it will be well supported everywhere. But right now, making 7zs might restrict some people from reading the files at all, and that’s not a good thing.

Note that any kind of self-extracting archive only creates even more problems for those who use platforms other than Windows. .EXEs are Windows executables, not universal ones.

tar.bz2 :bigsmile:

(although I don’t really recommend using it over rar or 7zip, the compression ratio isn’t as great)

also, less well known, but p7zip works on most posix systems just fine (linux, bsd, os x, what have you), and is easily available for fedora, debian and most other linux distros.

Isn’t this really a moot point for C0deKing’s purposes? I mean, how many flashers are there for Linux? I’ve only seen DOS or Windows based flashers for LiteOn. I’ll be happy to be corrected on this, though.


You can delete files from a non-solid 7z archive using the 7-Zip File Manager (part of the official 7zip distribution). I just confirmed this with v4.42.

:iagree: & I can’t really say that not going solid has made any of my files that much larger…

As a matter of fact, I recently backed up my firmware collection for my drives in a 7z archive, and the solid version wasn’t any larger or smaller than the non-solid version I need & use.

Plus, with solid archives, 7-Zip had to extract EVERYTHING to a temp folder in order to get a 2 MB firmware. :doh: [I’m not sure if 4.55 fixed that or not, though.]

CK’s utilities works great under wine. tends to mess up sector 0 (1?) of primary hard drive though so you might have to regrub it.

Well I ended up finding another way to get around the problem. I wrote a completely new flasher that is only 3MB in size. :slight_smile: Here’s what it looks like in action:

Why going the easy way when a complicated is possible too :stuck_out_tongue: