Menu

#268 Bad decode of PNG48 image

v1.0_(example)
closed-invalid
nobody
None
5
2014-06-04
2014-06-03
Tom McClure
No

gm convert crlogo.png -strip PNG00:crlogo.png

no errors but the input image is not recognized as 48-bit PNG and the output image is created as 8-bit PNG, gets totally mangled.

FWIW, works fine in imagemagick.

1 Attachments

Discussion

  • Glenn Randers-Pehrson

    The attached crlogo.png seems to be a PNG24 (8 bits per component)

     
  • Glenn Randers-Pehrson

    gm-1.3.18 and gm-1.4 recent snapshot are not showing me any problems converting crlogo.png to png00:crlogo_00.png

     
  • Tom McClure

    Tom McClure - 2014-06-03

    Holy transformation, batman! Looks like sourceforge has modified the image, just downloaded the attachment and got a different file altogether.

    Uploading inside zipfile to sidestep this nonsense.

     
  • Bob Friesenhahn

    Bob Friesenhahn - 2014-06-04

    Based on the PNG extracted from the zip file, I am not seeing any problems with Q8 or Q16 builds of GraphicsMagick 1.3.19 and this file. What version of GraphicsMagick are you using? There are older versions which did corrupt such files when reading.

     
  • Glenn Randers-Pehrson

    It appears that both gm-1.4/Q16 and im-6.8.9-2/Q16 are converting the image correctly to a 48-bit RGB image, but "gm display/Q8" is showing them both wrong (stretched horizontally). "im display/Q8" shows them correctly. I'm using gm version 1.3.18(Q8) for displaying.

     

    Last edit: Glenn Randers-Pehrson 2014-06-04
  • Glenn Randers-Pehrson

    Verified that a recent install of GM/Q8 display is showing the test image properly. The old versions that come with an up-to-date Ubuntu 14.04LTS do not work with the test image. It's GraphicsMagick 1.3.18 2013-03-10 Q8.

     
  • Glenn Randers-Pehrson

    Closing as invalid because the most recent version seems to work properly.

     
  • Glenn Randers-Pehrson

    • status: open --> closed-invalid
     
  • Tom McClure

    Tom McClure - 2014-06-04

    Confirmed, we are running a stock 1.3.18 here. I will see if we can install a 1.3.19 build on our servers. Thanks!

     

Log in to post a comment.

MongoDB Logo MongoDB