How to specify device in va plugins

General Discussion
1

Hi,
gstreamer 1.24 recommends using va plugins to replace vaapi plugins.
I can specify device via GST_VAAPI_DRM_DEVICE environment variable when using vaapi plugins, how can I do this with va plugins?
I found that there is a “device-path” property in va plugins, but it is read only.
Are there any documents I can refer to?
Thank you!

2

Hi,

If you have more than one device, it should register elements using a different name for each device. For example, for an H.264 encoder, the first one will be “vah264enc”, but the second one will have a name including the device name in it.

Olivier

3

Hi Olivier, thanks for your reply!
I can get available elements with different devices via gst-inspect, it’s really helpful.

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However, there is only “vah264dec” and no “varenderD129h264dec”, I know it means “vah264dec” uses renderD129 by default. Similarly, other element like vapostproc uses renderD128 by default.
Does the default device for these elements always the same for multi-device system? For example, can I say “vah264dec” will always use renderD129 by default if renderD129 exists?

Thanks,
Zhaojie