more questions

[Tim-Philipp Müller]

On Sat, 2021-04-24 at 15:18 +0800, James via gstreamer-devel wrote:

Hi,

> Learning but still lots to go.
> 
> I have a test pipeline
> 
> gst-launch-1.0 -t v4l2src name=source device=/dev/video2 ! \
>             video/x-h264,width=1920,height=1080,framerate=30/1 ! \
>             h264parse ! queue ! avdec_h264 ! \
>             autovideosink
> 
> 
> I coded that as
> 
>         pipeline = gst_parse_launch ("v4l2src name=source ! "
>             "video/x-h264,width=1920,height=1080,framerate=30/1 ! "
>             "h264parse ! queue ! avdec_h264 ! autovideosink", NULL);
> 
> The two do not yield the same result, in particular the gst-launch
> does feedback 1920x1080 to the card.
> The compiled code does not, so the card stays in its native 720x576
> resolution.
> 
> What and why
> 
> https://gstreamer.freedesktop.org/documentation/tools/gst-
> launch.html?gi-language=c
> 
> says -o file, but that option does not exist. How can I find what
> parse did to make a pipeline

gst-launch uses gst_parse_launch() so it should behave the same.

Your gst-launch pipeline has an additional device=/dev/video2 though?

Cheers
 Tim