JPEG quality in UIImageView...

Anyone know why JPEG images when loaded into a UIImageView appear with poor quality (pixelated). When I load the same image converted to a PNG then the image appears correctly (no loss of quality). If I load the same JPEG image into preview it looks fine too.
Anyone have any suggestions?
Thanks.

You should typically avoid any kind of scaling of images in
Flash, both up and down, unless you want a degraded look.

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I have no idea why you would want to do anything
Some people want lower quality to reduce file size for different reasons
It is an option - if you do pot want to do that do not use that option
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Try CatchAsBitmap:
http://www.republicofcode.com/tutorials/flash/as3cacheasbitmap/
Also check whether the quality is good when viewing it in actual percentage, are you changing the dimensions of image after loaded?
Someother Snippet to smooth the image:
_urlRequest=new URLRequest("pathtofile");
_loader=new Loader;
_loader.load(_urlRequest);
_loader.addEventListener(IOErrorEvent.IO_ERROR, function(e:IOErrorEvent):void{ trace(e) });
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Export JPEG quality must be chosen twice

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The High setting gives you the same file size as the original file was. The medium setting results is aboutg a 50% file size reduction. The max selection greatly increases the file size but I'm not sure it increase the image quality to any noticable degree.
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OT

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Is there a way to adjust the jpeg quality when exporting or editing? I can change the image size, which is helpful, but it would be nice if I could change the jpeg compression in order to reduce the file size. Thanks!

Hi Stanleydad,
i noticed from you other post that you are using AOL.
In iPhoto Preferences, have you chosen AOL as your email client.
Once you do this, when you choose an images within iPhoto and click the email icon, iPhoto will open your AOL mail client and attach the photos with the size you chose in the export dialog.
You might even want to make a new post that is all yours so it is easier for us to address all your needs.
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PS 7 similar to LR 60
PS 8 similar to LR 65 (62-69 gives same value)
PS 9 similar to LR 75 (70-76 gives same value)
PS 10 similar to LR 80 (77-84 gives same value)
PS 11 similar to LR 90 (85-92 gives same value)
PS 12 similar to LR 100 (93-100 gives same value)
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To me it would depend on the purpose. I do a lot of printing at home, so I don't use jpegs for that. But, for high quality prints done externally, I believe a lot of people resize their files in Photoshop and then sharpen for the print job, then save either to jpeg or tiff. Tiff is the safest because it avoids the lossy compression of a jpeg. If your resize is successful and you need to save to jpeg, then I imagine the highest quality setting would be desirable.
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But JPEG compression isn't just about "pixels being thrown away," and it's relative to the original. What could be happening in this case is:
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I am having difficulty having work accepted by iStock - even at full size at 100% jpe
g export, there is still some. I have cut way back on all enhancements.
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Greg Summers

Aren't these stock agencies a little paranoid about noise?
Lightroom 3 images may look a little noisier than LR2's at the same slider values. So you might need to add a little more luma noise than before.
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Jpeg Quality is the amount of compression applied to the file.
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Regards
TD

Jpeg Quality Slider Question

Greetings All!
I am new to Flash CS5 and I have created a slide show. I am trying to reduce the .swf file size for faster loading. I have been trying
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Thanks Kglad! That was exactly what I was missing.
That made a huge difference!
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Decreasing JPEG quality sometimes works

I've done about a hundred flash files with imported jpegs and
have had no trouble getting the global jpeg quality setting to
affect them. Now I've got a similar project of ten fla files that a
contractor did and I can't get the Jpeg quality setting to affect
the published files.
The point is that I know this setting can have an effect on
imported jpeg bitmaps because I've done it so many times now.
Now, in my own projects, all the jpeg bitmaps are set to "use
document default quality" and the global setting affects them. The
contractor's projects have the same settings but the global setting
has no effect.
The one thing I'm suspicious of is that her bitmap properties
point to originals that are on her computer, not mine. Could the
fact that her sources are unavailable have anything to do with
this?
Rob Mack

Okay, here's the answer. My previous several thousand jpeg
images had been saved with the progressive switch turned on.
Evidently, Flash compresses bitmaps in non-progressive jpeg
format. If the asset is already in this format then flash defaults
to using the original file as is. However, if the jpeg asset is in
progressive format then Flash has to recompress it.
The effect is that progressive jpeg files can be affected by
the project's global jpeg quality settings but non-porgressive
jpegs can't be affected by the settings.
How this affects a user depends on what you want to do. In my
case I'm doing dozens and dozens of files that are much like slide
shows and it's most convenient to adjust compression in the project
settings to get the file size down. For most other users, they've
gone to a bit of trouble to get a jpeg image "just right" and don't
want the global setting to affect it. In most users cases they'd
want to save non-progressive jpegs, in fact since the project
setting will skip them this is the better way to go when mixing
jpeg and png bitmaps.
For someone in my position where you need to be able to
recompress the bitmaps, you either save jpegs with progressive
switched on or you save the bitmaps in PNG format. Overall, using
PNG will probably cause less overall image damage but it increases
your storage requirements quite a bit.
So, what if you saved the jpegs in the wrong format? Maybe
the best choice would be to go back to photoshop and set up a batch
action to resave everything with Progressive on or off. Then in the
FLA file you can select all the bitmaps and update them in bulk.
Rob Mack

Photoshop CS4 jpeg quality default

Quality default when saving a jpg picture was always 12/maximum in my CS4. (That was great!) Suddenly it switched to 5/medium for NO reason! And I'm working on hundred of pictures - I really don't want to change it manually each time, but it seems to be impossible to change default settings for that (as long as it does not change just for fun like it did!)
Can someone PLEEEEAAASE help me, before I go completely crazy! It's much too expensive to waste my time like that...
For anyone who can solve my problem: THOUSAND thanks in advance!
Greetings Michael

That would say that if Photoshop was the app that saved a JPEG in the first place, that it must put the quality setting in the file somewhere, so that it will use that as the default the next time. I suspected it might be doing that (which is why I wrote "I could be wrong" i my first post) but wasn't sure as I have not tried to analyze the default quality setting before.
But I just tested it and this seems to be the algorithm:
1. If you open a JPEG saved by some other means (e.g., an out-of-camera JPEG or from another app) Photoshop appears to default to the last setting at which you saved any prior JPEG from Photoshop .
2. If you open a JPEG that was saved by Photoshop, it will read in the quality setting from the EXIF information in that file somewhere and use that as the default for the next File - Save As (and also plain File - Save apparently).
-Noel

Jpeg quality on export

I am experiencing a problem with the quality of the jpegs I get when exporting from Aperture. What I want to do is export adjusted NEF files to jpeg at the highest quality but at a reduced size to fit within 950x950. I have a preset arranged and the exported file is at the correct size. The resulting file however is not as sharp as I would expect and often has indistinct but readily visible flaws (almost as though the pixels have not been perfectly put together).
The same file exported from a trial version of Lightroom 2 are pixel perfect and visibly sharper. I have been viewing both exported jpeg files in Preview. I really like Aperture and use it a great deal. I do however need to sort this problem out asap.
I would be very grateful if you have any ideas on how to resolve the matter.
Thanks.
Simon.

Thanks very much for your input Ian. Here are a couple of examples. Small differences to be sure (although I have seen worse than this), but visible nontheless. I would look particularly at the rendering of the sea near the rocks on the left of the picture
Aperture:
http://swjones.onexposure.net/photos/6098/aperture-version/
Lightroom:
http://swjones.onexposure.net/photos/6099/lightroom-version/
Both images had the same export presets.
Thanks again, any help gratefully received.
Simon.

JPEG quality in UIImageView...

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