| Summary: | PNG image in CBZ wrapper does not display correctly (but PNG itself does) | ||
|---|---|---|---|
| Product: | [Applications] okular | Reporter: | Cory F Cohen <cfcohen77> |
| Component: | Comicbook backend | Assignee: | Okular developers <okular-devel> |
| Status: | RESOLVED WORKSFORME | ||
| Severity: | normal | CC: | aacid, gaetan.gilbert, luigi.toscano |
| Priority: | NOR | ||
| Version: | 0.14.3 | ||
| Target Milestone: | --- | ||
| Platform: | Ubuntu | ||
| OS: | Linux | ||
| Latest Commit: | Version Fixed In: | ||
| Attachments: |
The CBZ version of the file that exhibits the problem.
The PNG version of the same file that does NOT exhibit the problem. A nearly identical CBZ that generates some errors, but still displays. |
||
Created attachment 74039 [details]
The CBZ version of the file that exhibits the problem.
Created attachment 74040 [details]
The PNG version of the same file that does NOT exhibit the problem.
Created attachment 74041 [details]
A nearly identical CBZ that generates some errors, but still displays.
I also should have mentioned that the problem exhibits for some files, and not for others. This is an example of a similarly encoded PNG file that works just fine when enclosed in a CBZ wrapper.
Hi Cory, thanks for the report, I've opened attachment from comment one using Okular 0.15.1 and kdelibs 4.9.1 and it works fine (the page gets shown correctly) so I'm closing this bug as worksforme. If you can update to Okular 0.15.1 and kdelibs 4.9.1 in the future and you still have this problem please reopen this bug. Thanks for caring about Okular and reporting this bug :-) Thanks, I've upgraded to KDE 4.9.1 (Okular 0.15.1) using the repository at ppa:kubuntu-ppa/backports, and I can confirm that the bug is fixed for me as well. I've found a number of other bugs in various KDE apps before the upgrade and want to be running the latest version before reporting any more of them. Is the kubuntu backports ppa relatively stable or is truly bleeding edge? Sorry, can't really answer about the stability of kubuntu ppas or not Does not work for me with okular 20.12.3 (debian testing, KDE frameworks 5.78.0, Qt 5.15.2, libpng 1.6.37-3) Both attached cbz display the okular icon and output on stderr: libpng warning: zTXt: CRC error libpng error: PNG unsigned integer out of range QImage::scaled: Image is a null image libpng warning: zTXt: CRC error libpng error: PNG unsigned integer out of range QImage::scaled: Image is a null image libpng warning: zTXt: CRC error libpng error: PNG unsigned integer out of range QImage::scaled: Image is a null image libpng warning: zTXt: CRC error libpng error: PNG unsigned integer out of range QImage::scaled: Image is a null image (the same thing for both files, on files without buggy images nothing is printed) Opening the images directly without the cbz wrapper works fine. As the error message is different than the old one, and the old bug is related to a totally different version of the underlying software stack, please keep this closed and open a new bug. OK, here's https://bugs.kde.org/show_bug.cgi?id=436086 |
This bug report is probably exposing some inconsistency in the library used to render images between the comic book backend and the default image handling library. I would expect the problem to be upstream somewhere, but I have no idea where. A number of messages such as these are printed to stderr: QIODevice::read: Called with maxSize < 0 QIODevice::seek: Invalid pos: -6 QImage::scaled: Image is a null image I'll try to attach a demonstration file if I can figure out where to upload it to the bug report. Reproducible: Always Steps to Reproduce: I also suspect that the problem is also related to handling of 1-bit deep PNG images (which have historically had problems in a number of applications that otherwise support PNG images). The characteristics of the image are: $ gm identify -verbose okular-test.png Image: okular-test.png Format: PNG (Portable Network Graphics) Geometry: 2722x3776 Class: PseudoClass Type: bilevel Depth: 1 bits-per-pixel component Channel Depths: Gray: 1 bits Channel Statistics: Gray: Minimum: 0.00 (0.0000) Maximum: 255.00 (1.0000) Mean: 251.17 (0.9850) Standard Deviation: 31.02 (0.1216) Colors: 2 0: ( 0, 0, 0) black 1: (255,255,255) white Resolution: 72x72 pixels Filesize: 38.2K Interlace: No Orientation: Unknown Background Color: black Border Color: #DFDFDF Matte Color: #BDBDBD Compose: Over Dispose: Undefined Iterations: 0 Compression: Zip Comment: generated by unpaper Create-date: 2008-04-02T20:07:08-04:00 Modify-date: 2008-04-02T20:07:08-04:00 Signature: ba1078561438738723d855335e97b5f0745cb53153d9f75697b06ae5c2fd6dee Tainted: False User Time: 0.070u Elapsed Time: 0:01 Pixels Per Second: 326.7M Actual Results: The page just display with the Okular icon. Expected Results: The actual image.