v4l2-ctl --stream-out-dmabuf example not working

v4l2-ctl --stream-out-dmabuf example not working

[Vedant Paranjape]

Hello,
I am using the master version of v4l2-utils, found the example to
Stream video from a capture video device (/dev/video1) to an output
video device (/dev/video2) here:
https://manpages.debian.org/unstable/v4l-utils/v4l2-ctl.1.en.html

Here are the steps I have followed.
1) sudo modprobe vivid
2) v4l2-ctl -d0 --stream-mmap --out-device /dev/video3 --stream-out-dmabuf

Here's the output v4l2-ctl --list-devices
<snip>
vivid (platform:vivid-000):
        /dev/video2
        /dev/video3
        /dev/radio0
        /dev/radio1
        /dev/vbi0
        /dev/vbi1
        /dev/swradio0
        /dev/media1

HD WebCam: HD WebCam (usb-0000:00:14.0-7):
        /dev/video0
        /dev/video1
        /dev/media0
</snip>

Error out on running the program:
<snip>
                VIDIOC_G_FMT returned -1 (Invalid argument)
<VIDIOC_QBUF: failed: Invalid argument
handle out -1
handle out2in -1

</snip>

> https://git.linuxtv.org/v4l-utils.git/tree/utils/v4l2-ctl/v4l2-ctl-streaming.cpp#n2669
While I was able to solve the VIDIOC_G_FMT returned -1 (Invalid
argument) by  changing the "fd.g_fmt" to "out_fd.g_fmt"

Regards,
Vedant