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Old Jan 24, 2004, 10:42 PM   #1
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Default Is "Camera and Scanner Wizard" Lossless?

History: my old digicam (1.4MP) used SmartMedia, and I normally downloaded contents of SM cards using Flashpath and Microsoft Explorer. After downloading, I used PIE (Picture Information Extractor) to rotate portrait format shots to their proper vertical orientation, and to rename all photos with my own date conventions. The specific reason for choosing PIE is due to its use of “lossless” rotation—it manages to rotate the JPEGS without having to open and save them again, so no loss in involved in recompression.


Fast forward: I recently got a new 4MP digicam that uses xD cards and due to the hefty increase in card capacity, decided to use this opportunity to move to a card reader. Fine. The Microsoft “Camera and Scanner Wizard” that comes with Windows XP boots up each time I insert my card reader into my computer, and is quite handy for downloading pics from my memory cards. It also allows me to rotate prints as I save/rename them, so I don’t need PIE for that—or do I? I’m wondering if the Wizard’s rotation is lossless like PIE’s, or whether it’s actually recompressing the photos each time they’re rotated.
I’ve been doing a Web search, but found nothing pertinent. Anybody got some skinny on this issue?

TIA
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Old Jan 24, 2004, 11:14 PM   #2
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Default Re: Is "Camera and Scanner Wizard" Lossless?

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I’m wondering if the Wizard’s rotation is lossless like PIE’s, or whether it’s actually recompressing the photos each time they’re rotated. TIA
Wouldn't the file size change if there was lossy rotation with recompression?
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Old Jan 25, 2004, 12:23 AM   #3
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Curiouser and curiouser.
Thanks for the reply, Alan. Actually, I'm discovering there is file size change even when the change is lossless, at least according to this thread on Photo Binbook

Here are some interesting (?) stats on some tests on a single photo:
Size of original while still inside xD card: 806,515
Rotated 90° using C&S Wizard, then downloaded to computer: 803,166

Downloaded to computer, then rotated using PIE: 811,545
Downloaded to computer, then rotated using PaintShop Pro, and saved using lowest compression setting: 1,382,368

Sooooo . . .
1. Wizard is an unknown, and it changes (decreases) file size
2. PIE is lossless, but it still changes (increases) file size.
3. PaintShop Pro isn't lossless, but it produces the largest file size after recompression. (What's it adding?)

The thread I referenced above gives several tips on how to determine whether a given photo is identical to another after rotation, but some of the methods are over my head (or I don't have the software to do it). For present, I think I'll begin saving the native format to computer, then copying a new version and rotating it using PIE like I used to.
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Old Jan 25, 2004, 3:58 AM   #4
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Quote:
Originally Posted by Norm in Fujino
Actually, I'm discovering there is file size change even when the change is lossless,
Here are three more (freeware) programs offering lossless rotation for you to experiment with....

irfanview: www.irfanview.com . You need to download the plugins as well as the main program

xnview: www.xnview.com Nice little viewer/converter from France)

PhotoStudio: www.stuffware.co.uk

If you change the filename, and add a title and other image info, the file size will change a bit, of course. If I were you, I'd make sure you work on several identical *copies* of the original file, because irfanview and xnview at least overwrite your original file (this is probably to keep it as nearly as possible the same). I'd then compare the filesizes of the after-rotation versions from each of the above programs and your own PIE with the one you're getting from XP.
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Old Jan 25, 2004, 5:25 AM   #5
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Default Re: Is "Camera and Scanner Wizard" Lossless?

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Originally Posted by Norm in Fujino
... It also allows me to rotate prints as I save/rename them, ...
If you are changing your original images, that is a bad idea. Those are your digital negatives - don't mess with them. No rotatation, renaming, editing, or any other change of any kind.
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Old Jan 26, 2004, 3:11 PM   #6
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I’m with Bill 100% in saving the originals untouched. If you are sure of loseless rotation that wouldn’t be bad, but I still like to save the originals.

When you open an image in PSP you are decompressing it to full size of 2272 X 1704 – probably 11-12 Mb. You could save it as an uncompressed TIFF at the full 11-12Mb or whatever it comes out to or save as a JPG. The higher the quality the larger the file up to probably 2.5Mb if you save at best quality. Once you open or change a JPG it is a real bad idea to save as a JPG again unless you are sorely pressed for storage space. The compression artifacts accumulate and the image will not be quite as good as your lower quality original since you can’t improve on that.

I like Irfanview for loseless rotation and sorting. You can make the thumbnails bigger and have a lot more information to work with. You can still delete, rotate or move images from the thumbnails.

I don’t know whether the scanner and camera wizard is loseless but I know Irfanview is. I think it just writes "rotation 2" or whatever to the EXIF.
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