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That's the reason I can't use ubuntu; Too many packages altered from upstream to work with some weird issue the maintainer had, then I got pushed away from Debian because whenever a feature had issues, I had maintainers just disable the feature and close the bug.

Lol. Ive been using LTS versions of Ubuntu (and just ubuntu in general, all different types) since 2007, and I can honestly say its probably the most stable OS I have ever used.

Though, I am not using regular Ubuntu with Unity. Im just Kubuntu 12.04.2, which is just awesome. I never have packages break because of the maintainer (actually one of the biggest groups of maintainers in Linux, besides Debian and RHEL), except for every once in a while.

I think you would have better luck now. haha

I understand Linux, and have used Arch, but its still a pain in the ass just to get an OS up when you just want to use Linux. I see a lot of beginners failing horribly trying to use Arch, because it is for advanced users, but I figure why reinvent the wheel? Unless Im building a custom OS for a specific reason, Id rather just have a packaged, ready to go OS. It takes much less time to clear out unwanted software than to build an OS from scratch on Arch.

But its whatever makes you happy. :) Thats the beauty of this OS. haha

Exactly :)

wrong thread

Edited by RoninDusette

Haven't checked in on these forums in a while.

I have simply ignored the warning as it is just that, a warning and not an error. The problem here does not lie with Arch, but with the version of libpng that Arch uses. Arch rarely patches software from upstream, this warning message is just a new feature in libpng exactly as intended from upstream.

I do agree with you DJYoshaBYD in that Arch is not for linux newbies, unless of course they are willing and able to learn it. My reason for using Arch is simply that when it comes to computers, this is what makes me happy. Now since Arch tend to use new versions as soon as they are available, it sometimes even leads to something breaking on update. Currently I can't update because nvidia propritetary driver combined with linux 3.10 kernel results in my laptop dying upon starting X, a lot of Arch users discovered this recently. Again, not a problem with Arch, it's just a problem with nvidia drivers with 3.10 kernel. Of course, I was admittedly scared that my hardware was dying, haha. Thankfully I just needed to downgrade the kernel. I do very much understand people that are turned off by how Arch works, but I think some of us just like having to work with our system. Same as some people enjoy tinkering with cars (I understand the conversion of chemical energy into mechanical energy causing the car to move, but don't ask me to look under the hood of a car), some people enjoy tinkering with the nut and bolts of their OS.

I have admittedly not looked what png images are affected since I have mostly ignored this warning. However, this could also lay with imagemagick. I know playonlinux requires imagemagick, and perhaps imagemagick creates images that libpng don't like.

It could be, but it appears that removing the color profile stored in the PNG's fixes the issue, and realistically, for icons, having a color profile embedded doesn't make a whole lot of sense.

It is just a warning, but you go to install an app and have to click ok twice to it, then start to type in the search box, and each letter causes the list to refresh, so you type a letter; click ok; type a letter; click ok. etc. It's quite painful depending on what you are searching for.

I can confirm that this annoying warning message also occurs with the OpenSuse Factory distro. I first noticed that this was occuring with PlayOnLinux 4.2.1-1.1 after updating my packages from OpenSuse 12.3 to OpenSuse Factory (latest packages). I believe that the warning started occuring with my update to Libpng16-16 (v 1.6.2-2.2).

Research into Libpng's documented changes led me to :

http://www.libpng.org/pub/png/libpng-manual.txt

Changes to Libpng from version 1.5.x to 1.6.x can be found in section XII. However, I will post the portion that I believe is relevant below for convenience.

Error detection in some chunks has improved; in particular the iCCP chunk
reader now does pretty complete validation of the basic format. Some bad 
profiles that were previously accepted are now rejected, in particular the 
very old broken Microsoft/HP sRGB profile.The PNG spec requirement that 
only grayscale profiles may appear in images with color type 0 or 4 and 
that even if the image only contains gray pixels, only RGB profiles may 
appear in images with color type 2, 3, or 6, is now enforced. The sRGB 
chunk is allowed to appear in images with any color type.

As you can see above, some of the bad profiles that were previously accepted are now being rejected.

From there, I decided to gather information from one of the PNG images that came with POL (as discussed earlier in this topic) that is causing the warning. I started with the cmd.png image and looked into more information about it by sending the commands below.

identify -verbose cmd.png

A lot of information was displayed about the PNG file as expected, but at the end of the ouput, the information that appeared relevant for researching this problem has been shown below.

Version: ImageMagick 6.8.5-7 2013-06-17 Q8 http://www.imagemagick.org
identify: iCCP: known incorrect sRGB profile `cmd.png' @ warning/png.c/MagickPNGWarningHandler/1830.

From here, I decided to research the png.c file to gather more information which led me into too much code to look at.

Afterwards, I decided to look for newer changes that have been made since ImageMagick 6.8.5-7 which was the version used for the PNG file (as shown above).

I came across discussions of corrupted color profiles regarding the JPEG format.
Also, if an image went from JPEG to PNG, it could cause the color profile to be corrupted. I'm assuming that this may be what has happened by creation of the images for POL. I'm not sure if this could be the only way that it could happen, but I believe that they have a fix for this with newer versions of ImageMagick.

The change log discussing this issue can be found below.

http://www.imagemagick.org/script/changelog.php

The changes that I believe are relevant has been shown below for convenience.

2013-06-26 6.8.6-3

Improve HCL to RGB roundtrip

(reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=22384).

Prefer external log configuration file to built-in (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=23640).

Do not log in the IsLinkedListEmpty() method to prevent overflow (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=23640).

Fix bug loading TGA image with 32-bit palette (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=17889).

Color profiles are no longer corrupted for the JPEG format (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=23651).

Repair problem with -emboss / -equalize problem (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=23643).

And on another version they have also made changes to keep from writing jpeg properties into a PNG output. The HCLpColorspace change also may be relevant.

2013-07-21 6.8.6.7 

Do not write "jpeg:" properties in a PNG output file (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=23794).

2013-07-24 6.8.6-7

Missing case for HCLpColorspace (reference http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=23811).

My conclusion :

For users using POL that have the warning message discussed, I recommend to follow the instructions discussed earlier in this topic to correct the images. However, there are also alternative ways to recreate the color profile if you wish to research into those ways.

For myself, I corrected this issue by manually changing each image by using the command below.

convert filename.png -strip filename.png

For the POL development team, please include images in the next version that do not have this issue. Consider trying the latest ImageMagick version for saving PNG files. I believe that the bug is originating from ImageMagick and not POL.

However, it is directly affecting POL users. I believe that it would be a disadvantage for users to consider downgrading their version of Ligpng to not see the warning. Reason being, the issues will still remain within the PNG files, but will just be suppressed. Also, I believe that users that have manually corrected the images for this warning themselves will appreciate not having to correct them again with any newer versions of POL.

Hope this helps.

Jayzon

Edited by Jayzon

Are there still corrupted images in the development version?
I don't think any of the systems I have uses the new libpng version...

I opened a bug report to keep track of the issue:
http://www.playonmac.com/en/issue-2839.html

Edited by petch

Are there still corrupted images in the development version?
I don't think any of the systems I have uses the new libpng version...

I opened a bug report to keep track of the issue:
http://www.playonmac.com/en/issue-2839.html

I checked some of the images in the development version which don't appear to have the problem when I inspected them. I am assuming that this has been fixed in the development version. Thanks!

Edited by Jayzon

I fixed this error on Arch by doing this:
cd /usr/share/playonlinux
for i in `find . | grep .png`; do convert "$i" -strip "$i"; done

thanks busybox42
that does the job

good and easy workaround before the dev version hits stable

Thanks busybox, worked for me as well

I applied that as well, and it works. It was just annoying more than anything. lol.

Im running arch now, as well. I stand corrected. Arch rocks. Its for sure not for beginners, but its dope.

Thanks, busybox42

I was able to "fix" this problem by obtaining sRGB_v4_ICC_preference.icc from http://www.color.org/srgbprofiles.xalter and placing it with other profiles in  /usr/share/color/icc/colord/.

For all the subdirectories in /usr/share/playonlinux/resources/, I ran the command

# for x in *png; do convert $x -profile /usr/share/color/icc/colord/sRGB_v4_ICC_preference.icc $x; done

I'm using Mageia4 if that matters.

@DJYoshaBYD: One of us! One of us! ;)

Just to confirm that this is still an issue with the latest opensuse 13.1 and PoL 4.2.1
There is a post on their forum:
https://forums.opensuse.org/english/get-technical-help-here/games/491926-iccp-known-incorrect-srgb-profile-error-message-when-starting-playonlinux.html

and a hackaround:


su -

Code:

cd /usr/share/playonlinux

Code:

for i in `find . | grep .png`; do convert "$i" -strip "$i"; done

The problem also happens in Fedora 20. Editing the PNGs manually obviously works, but the fixed images should be included in the official distribution, since the repeated warnings are very annoying to endure.