Re: O.K. were not GEEK's but need computer HELP

Posted by seestheday on Feb 22, 2013; 2:46pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/O-K-GEEK-s-Fer-HELP-NOW-TYPE-OF-INTERNET-CHOICES-To-house-tp4036578p4036965.html



There is also a joke in bad taste about how winning an argument on the internet is like winning a race in the special Olympics... but here goes anyways.

I also should point out that if I'm wrong, then there is something that I fundamentally don't understand, and I want to correct that.  I hate not knowing.

To back me up a bit I should point out that when I was on a university co-op term I personally wrote software to render JPEG's and other image files as a part of the team that wrote imagenation: http://www.opentext.com/2/global/products/products-content-viewing-solutions.htm, although my primary contribution on that was on the PowerPoint rendering, I did help with a two image formats, TIFF and JPEG)
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I agree that if you explicitly re-save or write the file, then another compression will occur, and additional loss can be introduced at this point.

I disagree that simply opening and closing the file will re-compress it, and cause addition loss.

I'll walk through some thought experiments here to get my point across.  Please let me know where you start to disagree with any of my points.

1. Opening any standard file has zero impact on the original file (there are some cases with DRM'd files where this isn't the case, but that doesn't apply to JPEG's).  The file is only read.  No changes are made to it.

2. If you pull the power cord or battery out of your laptop after you have opened the file the original image is not changed.

3. If you are hosting a JPEG file on a web server and someone opens it up on a web page they cannot make changes to the original file.  If a random web visitor had write permissions to your remote web server that would be a massive security hole.

4. Developers/software engineers are generally rational people and would not unnecessarily waste computational time performing tasks that added no value to the program they are running.

5. Developers/software engineers are generally rational people and would not waste their time building/debugging software processes that add no value and aren't asked for by customers.

6. It is possible to have a software program that has the ability to decompress a JPEG, but not the ability to perform the actual compression and re-save it.

7. I concede that there may be a program that overwrites the original JPEG with a re-compressed file every time it is opened (anything is possible), but this is the fault of the program, and not an underlying issue with the JPEG standard.