Our company is developing video system that requires very low latency screen video output.
Our installation is: JETSON-TX2 + LI-IMX264 (2448x2058x25fps) + DELL u2412mb (8ms latency). We tried to use all possible variants of gst-launch, also tried to read image via system calls libv4l2 (V4L2_MEMORY_MMAP with VIDIOC_DQBUF, VIDIOC_QBUF etc). Unfortunately, we are not able to achieve latency less than ~120ms, our goal is 30-40ms. All discussions on forum that I’ve read does not provide a solution. The latency is measured by making photo of a timer on a smartphone.
The main questions are:
- What is the reason of this latency? Is it because of buffering mechanism in VI/V4l2?
- Is it possible to reduce latency to 30-40ms? May be there is some way to update VI and implement consecutive video readout and screen output in some RTOS-way?