rotate a jpg w/out lossey?

I have photoshop 7, can I rotate a .jpg pic 90 degrees without losing quality?
I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in re-compression, please advise, thanks
R. Hamm

As far as I understand, you won't lose any quality with the rotation (if its 90 degrees) BUT the moment you save that again as a jpg then that's where the loss will happen (regardless if you rotate or not) because it will compress the image again.

no idea on the jpg2000 thing.

"R. Hamm" wrote in message

I have photoshop 7, can I rotate a .jpg pic 90 degrees without losing quality?
I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in re-compression, please

advise,

thanks
R. Hamm

Good question. I couldn't find lossless rotation in the help search. I would be amazed if it was not a feature, though difficult to find, but.........

I always use freeware Irfanview to rotate digicam shots without recompression.
www.irfanview.com iMagine is another freeware viewer with minimum editing capabilities that also has lossless rotation

"R. Hamm" wrote in message

I have photoshop 7, can I rotate a .jpg pic 90 degrees without losing quality?
I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in re-compression, please

advise,

thanks
R. Hamm

"R. Hamm" posted:

I have photoshop 7, can I rotate a .jpg pic 90 degrees without losing quality?

No you can't with Photoshop.
I use Thumbs Plus to rotate without loss, to preview my images for Photoshop, and for simple cropping.

- Max

--
MisterMax
Slideshows of Angkor Wat, Bali, Crete, Maui, Malaysia, Morocco, Sicily (new), St Tropez, Thailand, Tour de France:
http://buten.net/max/
(Yes,RemoveDoubles is part of my email address. The double letters in my last name are not.)

"R. Hamm" wrote in
news:tETXa.72009$:

I have photoshop 7, can I rotate a .jpg pic 90 degrees without losing quality?

No. It is possible to rotate a JPEG-stored image in 90 degree intervals without any loss because all you really have to do is shift the order the bits appear in. Any other sort of editing changes the information in the pic and the image has to be re-compressed, losing more each time.

There are plenty of image viewers that will do the rotate and save, but as an image editor, Photoshop must re-compress the image.

I suppose it would be possible to write routines in PS that would recognize that you had only rotated at 90d., but they have chosen not to do so.

I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in re-compression,

I have no idea why you would think that.

No JPEG compression scheme will ever allow re-saving without loss, save for the rotation trick. Store you originals in a lossless format such as Tiff and only save out JPEGs when you absolutely have to. Further, almost all of those applications would involve somebody else viewing it, making JPEG 2000 worthless since it doesn't have any market penetration to speak of.

"R. Hamm" wrote in message

I have photoshop 7, can I rotate a .jpg pic 90 degrees without losing quality?
I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in re-compression, please

advise,

Not with Photoshop, but many other programs do lossless JPEG rotation. See http://sylvana.net/jpegcrop/losslessapps.html :
1.. Jpegcrop [Guido Vollbeding] (Windows) - Sample application
2.. cPicture [J

Thanks, that should work!

Not with Photoshop, but many other programs do lossless JPEG rotation. See http://sylvana.net/jpegcrop/losslessapps.html :

Amazing! Photoshop has no lossless rotate feature.

Now, just as surprizing to me is that imageN includes lossless cropping of jpegs.

Eric Gill wrote:

"R. Hamm" wrote:

I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in
re-compression,

I have no idea why you would think that.

JPEG2000 supports both lossless and lossy compression algorithms. Look at <http://www.fnordware.com/j2k/> for instance.

Further, almost all of those applications would involve somebody else viewing it, making JPEG 2000 worthless since it doesn't have any market penetration to speak of.

That's true. There are not much software out there that supports JPEG2000 at the moment.

--
Regards
Madsen.

Thomas Madsen wrote in
news::

Eric Gill wrote:

"R. Hamm" wrote:

I have seen something about jpg2000 format but do not know what it is, I thought it could be edited without losing in
re-compression,

I have no idea why you would think that.

JPEG2000 supports both lossless and lossy compression algorithms. Look at <http://www.fnordware.com/j2k/> for instance.

I knew about it. I'm willing to bet that Mr. Hamm is likely using JPEG because of the small file size and would be dissapointed again once he learned the 'lossless' option won't give him that.

Further, almost all of those applications would involve somebody else viewing it, making JPEG 2000 worthless since it doesn't have any market penetration to speak of.

That's true. There are not much software out there that supports JPEG2000 at the moment.

Unfortunately. Nor PNG, really. I lament this every time I have to compromise a web design to fit current standards.

Eric Gill wrote:

I knew about it.

Okay.

I'm willing to bet that Mr. Hamm is likely using JPEG because of the small file size and would be dissapointed again once he learned the 'lossless' option won't give him that.

Maybe not. Then he must choose between file size and quality like everyone else. :)

There are not much software out there that supports JPEG2000 at the moment.

Unfortunately. Nor PNG, really. I lament this every time I have to compromise a web design to fit current standards.

If you're using PNG like you use GIF then there's no problems. It's the 8 bit transparency thing that most browsers doesn't support. I have often seen that PNG has a better quality and a smaller file size than a GIF, but not much though. Often it's only a few bytes and who cares about that these days.

--
Regards
Madsen.

Thomas Madsen wrote in
news::

Eric Gill wrote:

I knew about it.

Okay.

I'm willing to bet that Mr. Hamm is likely using JPEG because of the small file size and would be dissapointed again once he learned the 'lossless' option won't give him that.

Maybe not. Then he must choose between file size and quality like everyone else. :)

Well, yeah. How many people have you run into on the usenet that want to hear that?

There are not much software out there that supports JPEG2000 at the moment.

Unfortunately. Nor PNG, really. I lament this every time I have to compromise a web design to fit current standards.

If you're using PNG like you use GIF then there's no problems.

....unless you have stubborn clients that won't bother to update their AOL to something from the last five years, and refuse to believe anyone else will, either.

It's the 8 bit transparency thing that most browsers doesn't support.

To me, that is much like saying "It's just those extra three zeros that won't be on your check!" That's the main benefit of PNG, bud!

I have often seen that PNG has a better quality and a smaller file size than a GIF, but not much though. Often it's only a few bytes and who cares about that these days.

<rude noise> ABC.com. Bounced my skyscraper ad because it was all of 38K.

I wondered why all the ads on their site looked so bad.