nvvidconv doesn't seem to work

Autonomous Machines Jetson & Embedded Systems Jetson TK1
1

I’m trying to do some format conversion/scaling with nvvidconv, and it doesn’t seem to work at all if I ask it to do anything.

L4T 21.3

Works, and displays video from my webcam to the screen (nvvidconv doesn’t do anything, of course):

gst-launch-1.0 -vvvvv v4l2src device=“/dev/video0” ! “video/x-raw,width=640, height=480, format=(string)I420, framerate=30/1”
! nvvidconv ! “video/x-raw,width=640, height=480, format=(string)I420, framerate=30/1”
! nveglglessink -e

Does not work, with only one difference (in bold):

gst-launch-1.0 -vvvvv v4l2src device=“/dev/video0” ! “video/x-raw,width=640, height=480, format=(string)I420, framerate=30/1”
! nvvidconv ! “video/x-raw,width=320, height=240, format=(string)I420, framerate=30/1”
! nveglglessink -e

The pipeline negotiates just fine, a 320x240 window is created, but I never see live video and the console outputs:

ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Internal data flow error.
Additional debug info:
gstbasesrc.c(2865): gst_base_src_loop (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
streaming task paused, reason error (-5)

I also can’t use it to change colorspace to/from GRAY8.

Any ideas?

ubuntu@tegra-ubuntu:~$ gst-inspect-1.0 nvvidconv
Factory Details:
Rank primary (256)
Long-name NvVidConv Plugin
Klass Filter/Converter/Video/Scaler
Description Converts video from one colorspace to another & Resizes
Author amit pandya apandya@nvidia.com

Plugin Details:
Name nvvidconv
Description video Colorspace conversion & scaler
Filename /usr/lib/arm-linux-gnueabihf/gstreamer-1.0/libgstnvvidconv.so
Version 1.2.3
License Proprietary
Source module gstreamer-nvvconv-plugin
Binary package GStreamer nvvconv Plugin
Origin URL http://nvidia.com/

2

Unfortunately I can’t say why nvvidconv doesn’t scale but if your only goal is to scale the video, then you should be able to do that more efficiently with the nveglglessink (at least if you control it from an application and not just using gst-launch).

3

Hi XPav,

nvvidconv does not support sw scaling between “raw-yuv → raw-yuv” formats.
You can use OSS “videoscale” plugin instead for any sw scaling requirements.

Please try with following example gst-launch-1.0 pipeline for webcam use-case with HDMI overlay sink.

gst-launch-1.0 v4l2src device=“/dev/video0” ! ‘video/x-raw, width=(int)640, height=(int)480, format=(string)I420, framerate=(fraction)30/1’ ! nvvidconv ! ‘video/x-raw(memory:NVMM), width=(int)320, height=(int)240, format=(string)I420’ ! nvhdmioverlaysink -e

Please try following example gst-launch-1.0 pipeline to change colorspace to GRAY8.

gst-launch-1.0 filesrc location=<filename_480p.mp4> ! qtdemux name=demux ! queue ! h264parse ! omxh264dec ! nvvidconv ! ‘video/x-raw, format=(string)GRAY8’ ! videoconvert ! xvimagesink -e

Please try following example gst-launch-1.0 pipeline to change colorspace from GRAY8.

gst-launch-1.0 videotestsrc num-buffers=300 ! ‘video/x-raw, width=(int)1280, height=(int)720, format=(string)GRAY8’ ! nvvidconv ! omxh264enc ! qtmux ! filesink location=test.mp4 -e

NOTE:
You can find more reference example gst-launch-1.0 pipelines in “Multimedia User Guide” available with L4T 21.3 public release page @ https://developer.nvidia.com/linux-tegra-r213

-Regards,
Amit Pandya

4

Hi,
I’m using a Tegra TK1 board for image processing and when i try to get the camera output using v4l2video capture it takes a lot of time for the camera to respond.The best way to reduce the time taken to process the image is to use the ISP provided by nvidia. So i found this page in nvidia forums where i found out that the ISP is not accessible directly and only through gstreamer.

I downloaded and installed gstreamer for nvidia TK1, ran the following command

“gst-launch-1.0 v4l2src ! tee name=t ! queue ! videoconvert ! autovideosink t. ! queue ! videoconvert ! jpegenc ! multifilesink location=~/gstrtemerexample/data/image_%07d.jpg”

i’m getting the jpeg images but its just a black/blank picture and the process is slow too what am doing wrong???.
details of the hardware are as follows :

board :TEGRA TK1
Camera : AR1820 MODULE .
System : running ubuntu

5

Hello, TSDCR:
Would you please file a new thread for your question? This one differs from main thread.
Let’s discuss your problem in your own thread.

thanks.
Chenjian