Hi, all
Our goal is to transcode 16 channels’ video to 1080p30fps H.264 with medium preset . But we found the issue that the transcoding performance will decrease when we set more than 8 channels.
The jetpack version is 4.6.1 and powermode is MAXN.
Here‘s the result:
Channels | Average FPS | Total FPS |
---|---|---|
6x | 77 fps | 462 fps |
7x | 66 fps | 462 fps |
8x | 58 fps | 464 fps |
9x | 36 fps | 324 fps |
10x | 27 fps | 270 fps |
We tested the performance with a local video through the following two commands:
Singelprocess
#!/bin/bash
./multivideo_transcode num_files 16 ./C2_line2fengqiRoad21_4M.264 H264 1.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 2.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 3.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 4.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 5.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 6.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 7.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 8.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 9.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 10.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 11.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 12.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 13.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 14.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 15.264 H264 ./C2_line2fengqiRoad21_4M.264 H264 16.264 H264 -hpt 3 -rc vbr -nrf 1 -ifi 50 -p high --stats
Multiprocess
#!/bin/bash
job=16
for ((i=0; i<$job; i++)); do
{
./multivideo_transcode num_files 1 ./C2_line2fengqiRoad21_4M.264 H264 $i.264 H264 -hpt 3 -rc vbr -nrf 1 -ifi 50 -p high --stats
}&
done
wait
echo "end"
Both commands showed the same results that it can only do 9 channels of 1080p30fps transcoding.
We also found the similar problem in this post.
https://forums.developer.nvidia.com/t/encode-performance-decreased-if-the-channels-over-8/198289
Please give some suggestions about how to enhance the transcoding performance.
Thanks!