I don’t think so, but I would not put a jpg into InDesign. I’d use tiff or psd.
I don’t use the .jpgs for print projects, but I need to know the answer for when I have to prep a file for others to use in their documents.
Basically for the Word users that snivel that a .tif file is too large and I want to warn them of the dangers of using .jpgs.
JPGs are fine for Word. Or save as PNG24.
If you open a JPG, edit it, save as JPG, then two days later, open it again, edit it, save as JPG, three days later, open it, edit, save as JPG, you’ll start to see very strong degradation of image quality. If you open the supplied JPG, edit it, save again (twice saved as JPG), you’ll be in fine shape, assuming you use high or maximum quality compression. People’s disdain for JPGs comes from exactly the same source as their disdain for Word, so you’re covered. 🙂
J
* grin*
I understand that, what I’m trying to find out is that when a Word file containing a .jpg is opened/edited/saved repeatedly, will that .jpg still compress itself?
No. It’ll be fine.
A small test here shows no degradation in 12 saves of a Word doc. But that is most certainly a question for another forum.
J
There is nothing wrong to use JPEG as a FINAL file delivery format as long as EVERYBODY understands that opening and re-saving will further degrade the image. So, it’s NOT a useful file format for exchange of working files that may need to be opened, adjust or changed and re-saved. That’s the critical distinction. And knowing that people may or may not fully grasp that distinction that makes JPEG a bit on the iffy side.
It should also be noted that there is a variety of compressions in JPEG and the high quality compression does very little damage while low quality and high compression can have an immediate negative impact on image quality.
I wish some of the JPEG knockers would read that!
To be clear, when you place a file in InDesign, no matter what you do to the InDesign file, you are not opening the actual placed file itself. If you DO open the placed file on Photoshjpop or whatever, then Save it, degradation can take place.
This is why you save an original .jpg and work with copies…many, many copies…
I understand that, what I’m trying to find out is that when a Word file containing a .jpg is opened/edited/saved repeatedly, will that .jpg still compress itself?
No. Word will embed the file "as is", meaning it creates a special data chunk that contains the full JPEG in its original state. If the users decide to use any of Word’s adjustments for color/brightness and so on, the image will be duplicated internally and another copy of the chunk appended as a BMP (up to Word 2003) or alternatively as PNG (Word 2007), leaving the original JPEG data untouched.
Mylenium
You should be careful with the page layout application’s output as these apps give you the option to compress the placed JPG image again during the PDF creation process. Watch your settings as you export PDF or send image data to the printer.
