使用videobalance调整gstreamer管道中的对比度和亮度将相机stream保存到文件

Question

I have a working gstreamer pipeline, using videobalance to adjust the contrast and brightness of a camera stream, the output of which is displayed on screen:

gst-launch-1.0 nvarguscamerasrc sensor-id=0 saturation=0 !
"video/x-raw(memory:NVMM),width=1920,height=1080,framerate=30/1" !
nvvidconv ! videobalance contrast=1.5 brightness=-0.3 ! nvoverlaysink

I want to do the same again, but this time record the camera stream to a file. I tried adding the videobalance element to the pipeline suggested by the authors of the drivers I'm using (which works fine otherwise):

gst-launch-1.0 nvarguscamerasrc sensor-id=0 saturation=0 !
"video/x-raw(memory:NVMM),width=1920,height=1080,framerate=30/1" !
nvv4l2h264enc ! videobalance contrast=1.5 brightness=-0.3 ! h264parse !
mp4mux ! filesink location=test.mp4 -e

But, I get the error:

WARNING: erroneous pipeline: could not link nvv4l2h264enc0 to videobalance0

Any suggestions for where I'm going wrong and/or possible solutions would be greatly appreciated.

Answer 1

NVidea encoders use NVMM memory, so it can't directly connect encoder to videobalance. Just adding simple video convert will solve the problem:

gst-launch-1.0 nvarguscamerasrc sensor-id=0 saturation=0 !
"video/x-raw(memory:NVMM),width=1920,height=1080,framerate=30/1" !
nvv4l2h264enc ! videoconvert ! videobalance contrast=1.5 brightness=-0.3 ! h264parse !
mp4mux ! filesink location=test.mp4 -e