I performed various bitrate tests on TK1 h264 encoder and I found bitrate/profile/level setting has some issues. My software version is R21.4.
- For bitrate even in the CBR mode (rc-mode=0), the lowest bitrate we can go is 500kbps for 1024x768. It looks like the encoder is trying to maintain some minimum framesize in the rate control algorithm.
GST_DEBUG=2 gst-launch-1.0 -vvv videotestsrc ! 'video/x-raw, format=(string)I420,width=(int)1024, height=(int)768' ! omxh264enc rc-mode=0 bitrate=500000 ! 'video/x-h264, stream-format=(string)avc' ! h264parse ! queue name=queenc ! mpegtsmux name=mux ! filesink location=test_low_500k.ts -e
2.Profile and level is hardcoded as CBP and level4.1. We would like to use up to high profile and level5.0, as we want to use CABAC and B frames. I tried to changed the code in gstomx1 but it seems that the encoder just ignore the setting in omx.
Does someone has the similar issue? Could NVIDIA experts provide some help on this?