medp7060 Posted March 20, 2020 Share Posted March 20, 2020 I often find some RAR files are well compressed. No matter what setting I use to re-pack the files after unpacking, I never achieve the same small size again. Are there any tricks for that. Here is an example: 552 MB (578,834,974 bytes) from here: Site: https://mega.nz Sharecode: /#!WrxRWJrJ!7M2kx0kjJK7u4Pm_dS5kGr5SafaR-L2qqciUL3bmBUI File name: TeraByte Drive Image Backup & Restore Suite 3.38_fu11.rar (password: softoroom) Unpack and then re-pack with the best setting: 833 MB (874,099,004 bytes) Thanks to TrojanK for correcting the link. Link to comment Share on other sites More sharing options...
TrojanK Posted March 20, 2020 Share Posted March 20, 2020 39 minutes ago, medp7060 said: https://mega.nz share code: /gomeganzWrxRWJrJ!7M2kx0kjJK7u4Pm_dS5kGr5SafaR-L2qqciUL3bmBUI (password: softoroom) Correct link: Site: https://mega.nz Sharecode: /#!WrxRWJrJ!7M2kx0kjJK7u4Pm_dS5kGr5SafaR-L2qqciUL3bmBUI File name: TeraByte Drive Image Backup & Restore Suite 3.38_fu11.rar Link to comment Share on other sites More sharing options...
hpwamr Posted March 20, 2020 Share Posted March 20, 2020 In some case "WinRar" has a much better compression rate than "WinZip" or "7-ZIP". Here an extreme case with very big text files: Test_big_files_till_4GB.rar (WinRar compressed up to 4.53 MB! --> compression <0.11% ! ) 😮 Link to comment Share on other sites More sharing options...
medp7060 Posted March 20, 2020 Author Share Posted March 20, 2020 I think the question was how the original packed files was able to achieve that high compression rate, which I cannot reproduce. i.e. 552 MB vs 833 MB in the above example. The difference is huge!!!!! Link to comment Share on other sites More sharing options...
Administrator DKT27 Posted March 21, 2020 Administrator Share Posted March 21, 2020 Topic moved to Software Chat. The place it was originally posted for is only for specific topics on the forums. Please check the compression method that has been used in the file after downloading it. Link to comment Share on other sites More sharing options...
xscorpionx Posted March 21, 2020 Share Posted March 21, 2020 22 hours ago, hpwamr said: In some case "WinRar" has a much better compression rate than "WinZip" or "7-ZIP". Here an extreme case with very big text files: Test_big_files_till_2GB.rar (WinRar compressed up to 2.89 MB! --> compression <0.06% ! ) 😮 hello, how can i doing this compression with winrar 5.80 x64? (best settings). Link to comment Share on other sites More sharing options...
hpwamr Posted March 21, 2020 Share Posted March 21, 2020 On 3/21/2020 at 6:46 PM, xscorpionx said: hello, how can i doing this compression with winrar 5.80 x64? (best settings). The WinRar settings are "Out-of-the-box" (default). But as already said, this is a case of extreme compression with txt files built with millions of repetitive lines. In any case, only WinRar (RAR5) could produce such extreme compression. With WinRar (RAR4), WinZip or 7-ZIP, the compression for this case was around 110,000 to 180,000 MB. Edited because the the test file is changed from 2GB to 4GB: Test_big_files_till_4GB.rar (WinRar compressed up to 4.53 MB! --> compression <0.11% ! ) 😮 Link to comment Share on other sites More sharing options...
Stig Posted March 22, 2020 Share Posted March 22, 2020 From my personal experiences, 7-Zip has always had the best compression. So, it's my go-to app when I want the best compression. And it compresses faster than WinRAR too. Link to comment Share on other sites More sharing options...
TrojanK Posted March 22, 2020 Share Posted March 22, 2020 On 3/20/2020 at 4:07 PM, medp7060 said: Unpack and then re-pack with the best setting: 833 MB (874,099,004 bytes) I got 552 MB (57,88,19,482 bytes) with the following settings using WinRAR v5.80.. Compression method: Best Dictionary size: 512 MB Create solid archive: Enabled Link to comment Share on other sites More sharing options...
SiNAN Posted March 22, 2020 Share Posted March 22, 2020 3 hours ago, TrojanK said: Compression method: Best Dictionary size: 512 MB Create solid archive: Enabled Got almost the same but compression was very slow Archive Format RAR (not RAR4) Archiving options : Create Solid Archive Compression method: Best Dictionary size: 512 MB Link to comment Share on other sites More sharing options...
GRiM Posted April 4, 2020 Share Posted April 4, 2020 The best settings for WinRAR to achieve maximum compression should be the following.. Enable RAR (RAR5), solid archive as well as set dictionary to max. [imf][/img] Link to comment Share on other sites More sharing options...
wolfie Posted April 9, 2020 Share Posted April 9, 2020 I use the 7-Zip settings shown below to get me great results. Note compression level, method, dictionary size, word size, block size, only one thread (slower but better), compress shared files Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.