Is there a material difference in the pixel error rate between using the "cut" vs...?

Question

..."copy" edit function?
Concerned with long term storage and access to Tiff and Jpeg files and not related to editing or compression software.

Answer 1

Data errors that might occur during a cut/copy/move file operation could come from memory errors. Most desktop and laptop computers don’t have ECC memory and memory errors will often go unnoticed. For desktop/laptop use, memory errors may not be frequent enough to cause a serious problem.



In terms of data integrity of the image files themselves, the most likely source of errors would be from the storage media. Magentic media can suffer from "bit rot" (http:// en.wikipedia .org/wiki/Bit_rot). Optical media (at least for consumer-grade equipment) has a significantly lower number of rewrite cycles before media failure. Flash memory wouldn't be a great choice for archiving due to the much shorter shelf life compared to magnetic and optical media. Some articles that may be of interest:

Digital Longevity: the lifespan of digital files

http://www. dpconline .org/graphics/events/ digitallongevity .html



The Optical Storage Technology Association Q & A page:

http:// osta .org/technology/ cdqa13 .htm When I’m archiving and/or backing up important files, I like to use file synchronization software that verifies file integrity. My preferred choice is something based on the rsync protocol (http:// rsync.samba .org/).

RsyncX (OS X) - http:// archive.macosxlabs .org/rsyncx/ rsyncx .html

DeltaCopy (Windows) - http://www. aboutmyip .com/AboutMyXApp/ DeltaCopy .jsp

Unison (Linux/Windows) - http://www. cis.upenn .edu/~bcpierce/unison/

Most file sync programs will compare dates and file sizes and some will also offer a checksum option. A simple CRC (http:// en.wikipedia .org/wiki/Cyclic_redundancy_check) would be okay, but something like MD5 would be even better. (http:// en.wikipedia .org/wiki/MD5).



Most CD/DVD burning software applications offer a verification step and it’s a good idea to use it when it’s crucial that there are no obvious file integrity errors.



Some more info on rsync, other file sync software and tips:

http:// en.wikipedia .org/wiki/Rsync

http://www. tomkelsey.pwp.blueyonder.co .uk/projects/ synchronizer_review .html#synctoy

http:// rsync .net/

Answer 2

Jpgs by their very nature lose quality every time you save them (from within a program). Tifs don’t. I normally save any photos I take (saved by the camera as a jpg) as a tif file and then use the tif file as a base for any manipulation, always keeping a good copy of the tif unchanged.

Anything that has type in it (fonts) or crisp edges will get fuzzy on a jpg.

You also need to keep an eye on your resolution. The higher the resolution, the clearer the pictures will be. Web images are usually at 72 resolution and highly compressed, so if you try to cut and paste from one of those into a print quality photo (200+ resolution) you will notice a huge difference.

Here is an article that explains all the different formats.

This is an extremely technical article comparing saving jpgs versus tifs for storage of digital photos. He concludes that he likes jpgs better.

You mention using "cut" versus "copy" but then say it’s not an editing issue, so I’m not sure what you mean. If you are talking about moving files, cut deletes the file from one area and pastes an exact copy some where else. Copy does the same thing without deleting the original--so you have two identical files. Neither changes the file in any way except location.

Answer 3

I'm not sure from your question just what you are trying to do. When you perform a cut operation, you are



Placing something on the Windows clipboard Deleting the information from wherever you got it.

When you perform a copy operation you are



Placing something on the Windows clipboard The cut operation is the same as the copy operation, resulting in the same data being put on the Windows clipboard. Pressing Ctrl+Z after a cut operation will undo the operation.



This will work the same way if you are cutting areas out of a picture with a photo editor (e.g. Photo$hop). The information on the clipboard will be exactly the same.



Cut and Copy with files also preserves the file information in the same way.



Does that cover it?

Answer 4

On Microsoft Windows, generally no - from what I've seen there is no difference between cut and copy. This could vary if an application uses custom cut/copy code (instead of just using the windows clipboard).

I have not used MacOSX or Linux/Unix as a desktop OS so can't comment on them.