Problem with streaked vertical lines

Mike Hardaker said:
Hi guys—sorry to be late to the party (it'd be really great, @Venomator, if there was a way to get an e-mail alert when tagged...)
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@Mike Hardaker - Hey Mike, firstly thanks much for dropping by to contribute to this awesome discussion, it is appreciated loads by all of us here and all such inputs are slowly helping the understanding of the issues... :thumbs:

Tags are a recent addition to the software we use on the site and adding them to e-mail notifications has not yet been added to the functionality... :rog:

We will fire a ticket off and see if this cannot be hurried along as it is a useful option to have, thanks for picking it up... :D
 
such a fab discussion!
I may not be a programmer but my mindset is very "detective" so I'm reading it all! can't wait till the culprit(s) are found and locked in place as hard evidence. :D
 
Original
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10 save
Here is pic that was taken as A max quality jpg in 645Pro and opened in Filterstorm and saved 10 times they look the same to me. 5s. And Ios 7.06
 
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image.jpg
1 st is original and last is tenth save JPEG. 645pro and Photofusion
Not much difference. I am sure there is degradation, but no vertical lines. Quality apps and and maximum quality compression. These photos have no editing
So Stackables, MikeHardaker, and tai Shimizu are correct. Better to be Tiffs or Png's , but jpegs can still be used with Ios7. I don 't know programming am I missing something?
 
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Hi, this is Pankaj, the developer of Leonardo.

I haven't gone through the entire discussion here but regarding the purple hue problem there are two aspects that I am aware of.

1. First was related to Leonardo. The clarity filter used to add purple hue on iPad Air and iPhone 5S. That was just a bug and has been fixed in the last update.

2. Now the second one is weird. On iOS 7, Apple's JPEG decoder (yes, the decoder, not the encoder!) degrades image quality and adds purple hue. Any API that creates a UIImage (a class that represents an image) from a JPEG file, like "imageWithContentsOfFile", degrades quality as well as adds a purple hue. If you do multiple read/write, the degradation accumulates and become quite visible.

I suspect that the purple hue problem reported in this discussion could be related to this bug. And if this indeed is true, the problem should not occur on iOS 6.

I filed a bug on iOS 7 regarding this issue. About a month back, I got a mail from Apple saying that they did some changes in iOS7.1 beta and asked me to redo the test with the latest beta. And it seems that the bug indeed got fixed. I can no longer reproduce the purple hue problem.

So, if some of you have developer license and want to verify if the problem really got fixed, you can try installing iOS 7.1 beta and see.

Regards,
Pankaj
 
Pankaj Goswami said:
Hi, this is Pankaj, the developer of Leonardo.

I haven't gone through the entire discussion here but regarding the purple hue problem there are two aspects that I am aware of.

1. First was related to Leonardo. The clarity filter used to add purple hue on iPad Air and iPhone 5S. That was just a bug and has been fixed in the last update.

2. Now the second one is weird. On iOS 7, Apple's JPEG decoder (yes, the decoder, not the encoder!) degrades image quality and adds purple hue. Any API that creates a UIImage (a class that represents an image) from a JPEG file, like "imageWithContentsOfFile", degrades quality as well as adds a purple hue. If you do multiple read/write, the degradation accumulates and become quite visible.

I suspect that the purple hue problem reported in this discussion could be related to this bug. And if this indeed is true, the problem should not occur on iOS 6.

I filed a bug on iOS 7 regarding this issue. About a month back, I got a mail from Apple saying that they did some changes in iOS7.1 beta and asked me to redo the test with the latest beta. And it seems that the bug indeed got fixed. I can no longer reproduce the purple hue problem.

So, if some of you have developer license and want to verify if the problem really got fixed, you can try installing iOS 7.1 beta and see.

Regards,
Pankaj
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Thanks @Pankaj Goswami
 
entusiasmo said:
Hi, Sam, I did another test with Photofusion with a new image taken with native camera app at full resolution (as usual, without crop or BW conversion).
Here is the result...

===========================
TEST - iPhone5S (IOS 7.0.5)
App: PHOTOFUSION
Image: taken with native camera app at full resolution
Process: simply open and save (JPEG 100% quality, setting compression slider to 1), without editing, no crop (10 times)
===========================

Original image
View attachment 51096
View attachment 51097

The final image (after 10 times)
View attachment 51098
View attachment 51099

Crop of original and final image:
View attachment 51101 View attachment 51100

I just sent you the original image via email.

I'm waiting for the result of your test, Sam!
Mauro
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Mauro, we conducted a test on the image you sent us and our results, more or less, match yours. The issue seems to be with Apple's encoding function UIImageJPEGRepresentation. Still investigating and will also verify if it has been rectified in 7.1 beta. More later!!
 
Stackables said:
Mauro, we conducted a test on the image you sent us and our results, more or less, match yours. The issue seems to be with Apple's encoding function UIImageJPEGRepresentation. Still investigating and will also verify if it has been rectified in 7.1 beta. More later!!
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Ok, Sam, I'm waiting for (good) news! ;-)
 
Since 7.0.6 I even have more problems uploading pictures on Instagram too. The black and white ones turn purple as well! :S

I use instagram just for rewarding pictures, so download from instagram participant pictures, place the watermark reward and upload to the gallery. Lately, they are turning more purple and it is in the upload phase, because I checked what I have on the screen and it's not the same after I've uploaded to the gallery! :S

I think the same happens with the wordpress app, if anyone is using it! just uploading make the pictures turn purple. Sigh!
 
davidroccato said:
Since 7.0.6 I even have more problems uploading pictures on Instagram too. The black and white ones turn purple as well! :S

I use instagram just for rewarding pictures, so download from instagram participant pictures, place the watermark reward and upload to the gallery. Lately, they are turning more purple and it is in the upload phase, because I checked what I have on the screen and it's not the same after I've uploaded to the gallery! :S

I think the same happens with the wordpress app, if anyone is using it! just uploading make the pictures turn purple. Sigh!
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I use IG and WP app are you talking about B/W only?
 
entusiasmo said:
David, it's a good (it means, obviuously, BAD!) example of this incredible issue...I noticed the same results when I upload my shots on Eyeem...no "pure" BW at all!
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Yes, another guy mentioned the same about EyeEm as well, and you just confirmed it. I just hope the 7.1 would fix this and I'm surprised that not so many people have realized this issue! Probably because too many use to look at the pictures from their telephones only and they don't realize the bad quality?
 
davidroccato said:
Yes, another guy mentioned the same about EyeEm as well, and you just confirmed it. I just hope the 7.1 would fix this and I'm surprised that not so many people have realized this issue! Probably because too many use to look at the pictures from their telephones only and they don't realize the bad quality?
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I agree after looking at yours then checking my feeds a lot are purple.
 
just a question Pankaj Goswami ... I noticed quite a few times, not anymore now mysteriously, that a square 2448x2448 image saved (from leonardo) to camera roll and then imported into handy photo lost 1 pixel in width and length (well it's square so the width and length terms aren't appropriate) ... anyway repeatedly I got a 2447 x 2447 file imported in handy photo. Not sure if the handy photo devs post here too ... I'll mail them too if needed.

Back to the main topic of this thread, I haven't experienced any of the issues mentioned here ... purple tone when saving multiple times ... lines etc ... I might not be using the apps that do that. But I do use some apps that over-compress images and I don't like that. Not an iOS issue so far ...
Just for info I'm using a 4s on iOS 7.0.6
 
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Philippe Schlossberg said:
Back to the main topic of this thread, I haven't experienced any of the issues mentioned here ... purple tone when saving multiple times ... lines etc ... I might not be using the apps that do that. But I do use some apps that over-compress images and I don't like that. Not an iOS issue so far ...
Just for info I'm using a 4s on iOS 7.0.6
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Look, this is going to sound ever more weird. I didn't have this problem editing with the iPad mini and iOS 7 but I've started to have it as soon as I bought the iPad mini Retina, with the same iOS 7 version I had in the iPad mini.

Is it possible that is not only software but it's software and hardware related?
 
just for info because someone mentioned photo stream in this thread ... here's a topic on Apple forums where I mentioned why I don't use it https://discussions.apple.com/message/22013201#22013201 I'm Arrow7 there ... I wouldn't mind starting a new topic about it here too ... but I seriously doubt that Apple will hear or change anything ... they're really stubborn about it.

David I can't tell as I cannot compare , I use my iPhone exclusively. My wife has a non-retina ipad mini that I never use to edit.
 
Philippe Schlossberg said:
just for info because someone mentioned photo stream in this thread ... here's a topic on Apple forums where I mentioned why I don't use it https://discussions.apple.com/message/22013201#22013201 I'm Arrow7 there ... I wouldn't mind starting a new topic about it here too ... but I seriously doubt that Apple will hear or change anything ... they're really stubborn about it.
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Please feel free to bring it on Philippe... :D

We need to have these things out in the open for MobiMembers to be aware of (not everyone uses, or wants to use Apple Forae!)... :rog:
 
davidroccato said:
Look, this is going to sound ever more weird. I didn't have this problem editing with the iPad mini and iOS 7 but I've started to have it as soon as I bought the iPad mini Retina, with the same iOS 7 version I had in the iPad mini.

Is it possible that is not only software but it's software and hardware related?
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I think you're right David. I just built a test app here based on what Mike H suggested earlier. Here are screenshots.

The first is my iPad mini

magshift_mini7.png


The second is the same code running on the iPad mini Retina

magshift_miniR7.png


Stripey !
 
Darren@RI said:
I think you're right David. I just built a test app here based on what Mike H suggested earlier. Here are screenshots.

The first is my iPad mini

The second is the same code running on the iPad mini Retina

Stripey !
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Darren@RI - Great illustrative examples Darren , thank you for sharing them... :thumbs:

Is this suggesting App Developers will now need to adjust their Apps for Retina Screen users then?... :rog:
 
Here's my code for fellow devs to validate (just in case I did something wrong!)

The imageview mentioned here is preloaded with a png containing a grayscale ramp in the storyboard.

Code: 
- (void)viewDidLoad
{
  [super viewDidLoad];

  dispatch_after(dispatch_time(DISPATCH_TIME_NOW, NSEC_PER_SEC+NSEC_PER_SEC),
  dispatch_get_main_queue(),^
  {
  UIImage* victim = imageview.image;
  
  const float compression = 1.0f;
  
  for( int i = 0 ;i < 25;i++ )
  {
  NSData* jpegrep = UIImageJPEGRepresentation( victim, compression );
  victim = [UIImage imageWithData:jpegrep];
  }
  
  imageview.image = victim;
  });
}
 
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