From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux 2.2.19 i686; en-US; rv:0.9.1) Gecko/20010607 Description of problem: All PNG files povray creates (as rendered output images) seems to have some extra IDAT chunks. How reproducible: Always Steps to Reproduce: 1. Take any scene, for reference, take following scene, let's call it scene.pov: camera { location <0,0,-1> look_at <0,0,0> } sphere { <0,0,0> 0.3 pigment { color rgb<1,1,1> } finish { ambient 1 } } 2. run $ x-povray +FN +Iscene.pov +Oscene.png 3. try to open scene.png in some program verbose enough about libpng errors, namely: GIMP, xv, ImageMagick, gqview, or anything else. Actual Results: The image scene.png is created. All programs mentioned in step 3 complain about libpng error. GIMP pops up a dialog saying there are too many IDATs in the file. Expected Results: The image scene.png is created. It can be opened in other programs without problems. Additional info: I don't have an independent PNG implementation, all the mentioned programs depend on libpng so, theoretically, it could be a libpng bug too. However, it doesn't look so.
This just creates a black background with a white circle, yes? Tim
POV-Ray uses the standard libpng to write PNG image files.
Yes, it just creates a black background with a white circle. My original description was not precise. The problem is not related to IDAT boundaries, there is simply some extra data. Because PoV-Ray creates PNGs with lots of small IDATs, it can sometimes seem there are whole extra IDATs.
Since powertools has been discontinued, we have no means of fixing this in the next release (because it won't be made).