.png vs .jpg playback mystery

[Sergei Vorobyov]

Greetings!

I am stuck with the following mysterious behavior of GStreamer. Maybe
someone has a clue?

1. Both

gst-launch filesrc location=file.jpg ! decodebin2 ! imagefreeze !
ffmpegcolorspace ! xvimagesink

gst-launch filesrc location=file.png ! decodebin2 ! imagefreeze !
ffmpegcolorspace ! xvimagesink

play just fine; moreover, the imagefreeze ! ffmpegcolorspace can be swapped.

2. However, when I turn it into the C code (omitting details like
declarations and checks):

  src = gst_element_factory_make ("filesrc", "source");
  g_object_set (src, "location", fname, NULL);


  conv = gst_element_factory_make ("ffmpegcolorspace", "ffmpeg-colorspace");
  sink = gst_element_factory_make ("ximagesink", "sink");