Are there any Parameters That Can be Passed to the HW Decoder to Change Decoder Behavior ?

Hi Folks,

I for the most part love the HW decoders and the output but in some cases I would like to control some features of the HW decoder for let’s say for example H265(assume HDR) to not do the PQ decode and color gamut correction. Does anyone know if parameters can be used to modify the HW decoder’s behavior? Is there a list of parameters somewhere? Thanks in advance for your help.

Hi,
we have tegra_multimedia_api and gstreamer.
In tegra_multimedia_api, please check options in 00_video_decode.

In gstreamer, please run ‘gst-inspect-1.0 nvv4l2decoder’ to show all properties.

The parameters you mentioned look advanced and may not be supported. Please share detail about the parameters required in your usecase.

Hi DaneLLL,

For example let’s again use the H265 decoder for HDR as our example. Do the H265 decode but do not do the PQ decode(decompander) and don’t make any changes to the color gamut. Is it possible to send those parameters to the HW decoder for H265 decode?

Hi,
We don’t have the parameters in current L4T releases. It is a new feature and we will check if we can support this case on Jetson Nano.

Hi Tom,
We have clarified that hardware decoder does not do PQ decode and make changes to color gamut. Hardware decoder does not support the functions.

If you see it working on other platforms and can configure the parameters to the decoder, please share us the information. We can check if we can have the usecase working the same on Jetson Nano.

Hi,
For more explanation about color gumat, if the source is Rec.709 10-bit H265 stream, after decoding, it is Rec.709 10-bit YUV4:2:0.

Hi Dane,

I still believe the HW decoder is doing the PQ decode(Perceptual Quantizer (PQ) transfer functions) of the HDR H265 encoded content. Could you please check again? Thanks.

Tom

Hi,
Video decode team has confirmed we don’t have hardware filter for PQ decode. Do you observe the difference between hardware decoder and software decoder? If you see the deviation between hardware and software decoders, please share us the steps of reproducing the issue. We can reproduce it and then ask for video decode team’s help to check and clarify it.