# mac jpeg format compatibility



## rhazeman (Nov 20, 2006)

How to make sure that the jpeg format saved from a Mac be compatible with a PC version?

It happened to me on 2 occassion:

1) I scanned photos on my Mac, save as jpeg format but I cant open it in a PC. Anything I should do?

Rizwan


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## simbalala (Nov 20, 2006)

They should open in any case but you can remove the data fork which contains the preview image (and other Mac specific info) by using Grim Ripper. It may be the cause of your problem.

http://www.macupdate.com/info.php/id/9105


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## Natobasso (Nov 20, 2006)

You may have saved your jpgs as CMYK since you're scanning them and that might be the default color space. Make sure you check your jpgs for RGB colorspace. Jpgs should open fine on both macs and pcs without any fiddling.


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## sinclair_tm (Nov 20, 2006)

well, if you are saving them as .jpeg, and not .jpg, then that might be what is throwing off the pcs.  they really don't do well with file extentions that are more than 3 letters/numbers long, or are missing.


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## Natobasso (Nov 20, 2006)

Good idea that. Your computer won't recognize the file if you use .jpeg instead of .jpg.


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## nixgeek (Nov 20, 2006)

Well, I've been able to open .jpeg files and .jpg files in Windows XP.  I'm leaning more to the fact that it was saved as a CMYK and not as RGB.  The same thing happened to my father who was working on a letterhead graphic on Illustrator.  He ended up exporting it to .jpg but it was using CMYK instead of RGB.  The second I exported it again in RGB, everything started working properly.


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## Natobasso (Nov 20, 2006)

Jpgs have to be in RGB format or they will give errors.


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## showngo (Nov 20, 2006)

One thought is that if you are hiding the file extension on the Mac, sometimes it send with out a file extension to a PC. And the PC will freak out. Make sure when you open it on the PC that it has the correct file extension on it, it may just be missing it.


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## Natobasso (Nov 21, 2006)

I don't think hiding the extension makes it go away, though.


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## showngo (Nov 21, 2006)

It doesn't make the extension go away on Mac OS X, but if you send that file to Windows sometimes OS X does not reapply the extension. May not be the problem but worth looking at, as it is a very simple fix.


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## Natobasso (Nov 21, 2006)

Have you witnessed this yourself? (Just curious because I haven't yet...)


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## showngo (Nov 21, 2006)

It has happened to me a couple of times, not a frequent thing. I always show the file extension though.


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## randalllharris (Sep 19, 2008)

I realize it has been a couple of years since you first posted this question.  

I am running into similar problems.  I was wondering if you have found a good solution.

My research has indicated to me that some WINDOWS applications cannot read some of the MAC JPEG files.  The windows XP operating system could display thumbnails of the files.  I did however find two applications that could read the MAC files.  One was Photoshop 4.0 and the other was GIMP.  The photoshop protested that the file was in the wrong format (RGB, I think or maybe it converted it to RGB)  Anyway it was able to read the file.  I could then resave the file and it could then be read by other PC applications.

This is not a problem with all jpeg files I get from macs.  It is a problem when the illustrator makes a high res copy that printers use for making nice looking booklets etc.  If the file is saved in progressive format it seems to be ok.

Any more help would be appreciated.
Thanks.
Randy


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## Natobasso (Sep 19, 2008)

Your issue could stem from 1) permissions issues on your jpg files or 2) saved as CMYK jpgs in which case this will cause errors.

As for your printing issue, please tell me you aren't printing hi res jpgs? You should export a pdf, preferrably PDF/X1-a. Jpgs, by virtue of their compression, are entirely not suitable for print.


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## randalllharris (Sep 19, 2008)

Thanks for the info I will pass it on to the person I know who is using the MAC.


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