[Bug 786320] New: periodic_keyframe max value

GStreamer (GNOME Bugzilla) bugzilla at gnome.org
Tue Aug 15 13:37:41 UTC 2017


https://bugzilla.gnome.org/show_bug.cgi?id=786320

            Bug ID: 786320
           Summary: periodic_keyframe max value
    Classification: Platform
           Product: GStreamer
           Version: git master
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: Normal
         Component: gstreamer-vaapi
          Assignee: gstreamer-bugs at lists.freedesktop.org
          Reporter: matteo.valdina at gmail.com
        QA Contact: gstreamer-bugs at lists.freedesktop.org
                CC: bsreerenj at gmail.com, vjaquez at igalia.com
     GNOME version: ---

Created attachment 357627
  --> https://bugzilla.gnome.org/attachment.cgi?id=357627&action=edit
patch to increase max period_keyframe

Current implementation of vaapih264enc enforces a keyframe each 300 frames at
maxinum.

This is translated to an IDR each 10 seconds at 30 fps or 5 seconds at 60 fps.

An IDR frame degrade the quality in the case you have a constrained bandwidth
(you can see blocks each 5 or 10 seconds).

In order to solve this scenario, I increased the max value of periodic_keyframe
to a higher value (MAX_UINT).

THe keyframe is generated only when there is a force_keyframe event inside the
encoder pipeline.

I tested with H.264 and I didn't see an issue or artifact appear after awhile.

There is another reason to kept the max value limited to 300? 

I attaching my changes for testing.

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.


More information about the gstreamer-bugs mailing list