MantisBT - ParaView
View Issue Details
IDProjectCategoryView StatusDate SubmittedLast Update
0014426ParaView(No Category)public2013-11-26 13:162014-01-11 08:39
ReporterGena Bug 
Assigned ToDan Lipsa 
PriorityhighSeverityminorReproducibilityhave not tried
StatusclosedResolutionfixed 
PlatformOSOS Version
Product Versiongit-master 
Target Version4.1Fixed in Version4.1 
ProjectSandia
Topic Name
Typeusability
Summary0014426: png screenshots have a huge size in 4.1.0rc1
DescriptionLast version of ParaView (4.1.0rc1) makes the huge size screenshots when choosing png format. Changing image quality isn't help -- the image size is always the same. I attached two screenshot of the same scene (see below), one from 4.1.0rc1 (screenshot.pv410rc1.png) and another from 4.0.1 (screenshot.pv401.png).

Steps to reproduce:
1. open pv
2. make a sphere (Sources -> Sphere) with the default settings
3. make a png screenshot with the default settings

Env: both ParaView (4.0.1 and 4.1.0rc1) downloaded from the size and installed on Debian testing amd64.
Steps To Reproduce
Additional Information
TagsNo tags attached.
Relationships
Attached Filespng screenshot.pv410rc1.png (1,976,424) 2013-11-26 13:16
https://www.vtk.org/Bug/file/9556/screenshot.pv410rc1.png
png screenshot.pv401.png (36,857) 2013-11-26 13:17
https://www.vtk.org/Bug/file/9557/screenshot.pv401.png
png
Issue History
Date ModifiedUsernameFieldChange
2013-11-26 13:16Gena BugNew Issue
2013-11-26 13:16Gena BugFile Added: screenshot.pv410rc1.png
2013-11-26 13:17Gena BugFile Added: screenshot.pv401.png
2013-11-26 14:28Alan ScottPrioritynormal => high
2013-11-26 14:56Utkarsh AyachitProjectParaViewPro => Sandia
2013-11-26 14:57Utkarsh AyachitProduct Version => git-master
2013-11-26 14:57Utkarsh AyachitTarget Version => 4.1
2013-11-30 04:18Paul EdwardsNote Added: 0031888
2013-12-04 17:02Paul EdwardsNote Edited: 0031888bug_revision_view_page.php?bugnote_id=31888#r675
2013-12-11 11:43Utkarsh AyachitNote Added: 0031921
2013-12-11 11:43Utkarsh AyachitAssigned To => Dan Lipsa
2013-12-13 15:40Dan LipsaStatusbacklog => active development
2013-12-16 11:40Utkarsh AyachitNote Added: 0031941
2013-12-18 17:04Dan LipsaNote Added: 0032024
2013-12-18 17:04Dan LipsaStatusactive development => gatekeeper review
2013-12-18 17:04Dan LipsaResolutionopen => fixed
2013-12-20 08:26Utkarsh AyachitFixed in Version => git-master
2013-12-20 08:26Utkarsh AyachitStatusgatekeeper review => customer review
2013-12-20 08:26Utkarsh AyachitNote Added: 0032034
2013-12-20 09:25Paul EdwardsNote Added: 0032041
2013-12-24 16:06Alan ScottNote Added: 0032049
2013-12-24 16:06Alan ScottStatuscustomer review => closed
2014-01-11 08:39Utkarsh AyachitFixed in Versiongit-master => 4.1

Notes
(0031888)
Paul Edwards   
2013-11-30 04:18   
(edited on: 2013-12-04 17:02)
Looks like this commit was adding support for compression with PNG images but set the default value to be 0 (no compression).

http://vtk.org/gitweb?p=VTK.git;a=commit;h=5d97d7df5c754d8609a746fdcb8d65736ab61f8b [^]

The compression level in the dialog isn't used unless jpeg is selected - it could be added in: ./ParaViewCore/ServerManager/Rendering/vtkSMUtilities.cxx (but would need to translate to the 0-9 that png writer expects).
(0031921)
Utkarsh Ayachit   
2013-12-11 11:43   
Thanks for the solution, Paul. That makes it easier :)!
(0031941)
Utkarsh Ayachit   
2013-12-16 11:40   
VTK gerrit topic: http://review.source.kitware.com/#/t/3720/ [^]
(0032024)
Dan Lipsa   
2013-12-18 17:04   
Hi Paul,
Note that in the 'Save Snapshot' dialog you can select the Image Quality. You cannot link that with the compression level for PNG as the image quality stays always the same - PNG is a loss-less format. Someone selecting highest image quality would get no compression for PNG, not a desired behavior.

So, in the fix I just set the compression level to 5, as per advice from

http://refspecs.linuxbase.org/LSB_3.1.0/LSB-Desktop-generic/LSB-Desktop-generic/libpng12.png.set.compression.level.1.html [^]
(0032034)
Utkarsh Ayachit   
2013-12-20 08:26   
Topics merged into master:
        14286_fix_orientation_widget
(VTK) 14426-huge-png
        14464_fix_specular_highlights
        14466_fix_calculator_panel
        disable-unified-bindings-by-default
        fix-collaboration
        fix_parallel_amrconnectivity
        gio-cleanup-and-warning-fixes
        pvweb-enhancements-events-protocols-docs
(0032041)
Paul Edwards   
2013-12-20 09:25   
Hi Dan,

You are right that it would be confusing and the dialog would need to be updated to accommodate it.

One minor point: the level would have originally been 6 as that is the default in zlib - see Z_DEFAULT_COMPRESSION here: http://www.zlib.net/manual.html. [^]

Regards,
Paul
(0032049)
Alan Scott   
2013-12-24 16:06   
Tested local server, both ParaView and pvbatch, master, Linux.