dv/AVI file compressed with winrar for storage at DVinfo.net

Dave Morgan · January 27th, 2010, 07:37 PM

I have a DV/AVI file that is 7.57 GB that i compressed with winrar at the highest setting and the file is now 3.88 GB. I did this so i could store it on a dvd-r for backup/archiving.

is that bad for the dv/avi file?

Perrone Ford · January 27th, 2010, 07:47 PM

Shouldnt affect it at all. Actually kinda cool you got that much compression. I would do a quick test on the file though to make sure it comes back as expected.

Marty Welk · January 27th, 2010, 08:18 PM

that is cool, never thought of that because most other highly compressed things dont squeeze much.

i just tested something, based on a hunch and previous info.
if I "corrupt" part of a DV file (but not the header) , just like the DV tapes data itself it will just glitch a bit and fly right on past it.
if I corrupt part of a zipped file with a DV file in it, it doesnt even work.
i corrupt part of a zip7 file and it stopped extraction at the corrupt point

i corrupted the file by opening them in a Hex Editor then zeroing out areas of thier data, so that isnt all the ways it could become corrupt, and either file could become corrupt and unreadable anyway. i just was remembering how Useless some compressed files were when parts of them became corrupted.
there is repairing stuff for compressed archives, but others have tried it and it often isnt so great either.

I did get more than 50% reductions also in compression, black background stuff.

So that would be one concideration, the DV file type is very robust and forgiving, an archive of it might not be as easily recoverable on a minor corruption of the data. It would still be a great way to web transport DV files.

because these types of compression are just finding repetition and patterns and attempt to keep every single bit of any file exactally the same, there is no "loss" in the compression.

January 27th, 2010, 07:37 PM	#1
Dave Morgan Major Player Join Date: Feb 2006 Posts: 293	dv/AVI file compressed with winrar for storage I have a DV/AVI file that is 7.57 GB that i compressed with winrar at the highest setting and the file is now 3.88 GB. I did this so i could store it on a dvd-r for backup/archiving. is that bad for the dv/avi file?

January 27th, 2010, 07:47 PM	#2
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	Shouldnt affect it at all. Actually kinda cool you got that much compression. I would do a quick test on the file though to make sure it comes back as expected. __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

January 27th, 2010, 08:18 PM	#3
Marty Welk Major Player Join Date: Sep 2008 Location: East Bay Cali Posts: 563	that is cool, never thought of that because most other highly compressed things dont squeeze much. i just tested something, based on a hunch and previous info. if I "corrupt" part of a DV file (but not the header) , just like the DV tapes data itself it will just glitch a bit and fly right on past it. if I corrupt part of a zipped file with a DV file in it, it doesnt even work. i corrupt part of a zip7 file and it stopped extraction at the corrupt point i corrupted the file by opening them in a Hex Editor then zeroing out areas of thier data, so that isnt all the ways it could become corrupt, and either file could become corrupt and unreadable anyway. i just was remembering how Useless some compressed files were when parts of them became corrupted. there is repairing stuff for compressed archives, but others have tried it and it often isnt so great either. I did get more than 50% reductions also in compression, black background stuff. So that would be one concideration, the DV file type is very robust and forgiving, an archive of it might not be as easily recoverable on a minor corruption of the data. It would still be a great way to web transport DV files. because these types of compression are just finding repetition and patterns and attempt to keep every single bit of any file exactally the same, there is no "loss" in the compression. __________________ ----------------sig----------------- Re-learning everything all over again, one more time.