V4l-encoder options for stringent bitrate

Hi.

I’m looking stringent bitrate options for omx-encoder (https://developer.download.nvidia.com/embedded/L4T/r32_Release_v1.0/Docs/Accelerated_GStreamer_User_Guide.pdf):

Stringent Bitrate must be enabled along with constant bit rate (control-rate=2), two-pass
CBR being enabled, and virtual buffer size being set

What are the recommendations for the v4l-encoder?

Particularly interesting is the way to determine the virtual buffer size to achieve a constant output bitrate and how it can be related to such parameters as resolution, pixel format, codec, fps, gop size. Perhaps something else can be used to select this value?

Hi,
Please refer to the setting in

Suggest you run in CBR mode and adjust virtual buffer size. Virtual buffer size is recommended in 0.75*(bitrate/fps) ~ 2*(bitrate/fps).

We don’t have the property of enabling stringent bitrate in v4l2 plugins. In the mode, the size of IDR/I frames is stringent and may lead to worse quality. Suggest you try CBR + vbv-size first.

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