rpicamera: support two CSI cameras at once (#1573)

[aler9]

Fixes #1573

[aler9]

@marksutheran here is the nightly release, let me know if it works with two cameras:

rtsp-simple-server_v0.21.6-3-g00f5fec_linux_arm64v8.tar.gz
rtsp-simple-server_v0.21.6-3-g00f5fec_linux_armv6.tar.gz
rtsp-simple-server_v0.21.6-3-g00f5fec_linux_armv7.tar.gz

[codecov-commenter]

Codecov Report

Merging #1574 (00f5fec) into main (33b72c5) will increase coverage by 0.02%.
The diff coverage is 100.00%.

📣 This organization is not using Codecov’s GitHub App Integration. We recommend you install it so Codecov can continue to function properly for your repositories. Learn more

@@            Coverage Diff             @@
##             main    #1574      +/-   ##
==========================================
+ Coverage   65.17%   65.19%   +0.02%     
==========================================
  Files          86       86              
  Lines        9410     9416       +6     
==========================================
+ Hits         6133     6139       +6     
  Misses       2829     2829              
  Partials      448      448              

Impacted Files	Coverage Δ
internal/conf/path.go	21.80% <100.00%> (+0.84%)	⬆️
internal/core/core.go	84.37% <100.00%> (+0.11%)	⬆️

... and 2 files with indirect coverage changes

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[marksutheran]

That was quick!

Quick test, running fine! And load is much reduced.

I will keep testing this out and play with higher frame rates etc

conf:

paths:
  cam0:
    source: rpiCamera
    rpiCameraCamID: 0
    rpiCameraWidth: 1920
    rpiCameraHeight: 1080
...
    rpiCameraFPS: 20
    rpiCameraIDRPeriod: 40
    rpiCameraBitrate: 4000000
    rpiCameraProfile: high
    rpiCameraLevel: '4.1'
...   
  cam1:
    source: rpiCamera
    rpiCameraCamID: 1
    rpiCameraWidth: 1920
    rpiCameraHeight: 1080
...

top:

top - 21:40:23 up  2:37,  3 users,  load average: 0.29, 0.28, 0.40
Tasks: 141 total,   1 running, 140 sleeping,   0 stopped,   0 zombie
%Cpu(s):  4.2 us,  3.4 sy,  0.0 ni, 92.3 id,  0.0 wa,  0.0 hi,  0.1 si,  0.0 st
MiB Mem :   7812.3 total,   7315.4 free,    208.1 used,    288.8 buff/cache
MiB Swap:    100.0 total,    100.0 free,      0.0 used.   7494.2 avail Mem 

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND                                                                                                                                                                         
   1523 mark      20   0  730472  31880  14404 S  15.9   0.4   0:19.20 rtsp-simple-ser                                                                                                                                                                 
   1532 mark      20   0  350608  10900   9524 S   5.0   0.1   0:06.46 rtspss-embedded                                                                                                                                                                 
   1534 mark      20   0  350608  10872   9492 S   5.0   0.1   0:06.90 rtspss-embedded                                                                                                                                                                 
     72 root       0 -20       0      0      0 I   1.7   0.0   2:20.47 kworker/u9:0-brcmf_wq/mmc1:0001:1                                                                                                                                               
    783 root       0 -20       0      0      0 I   1.7   0.0   2:29.41 kworker/u9:2-brcmf_wq/mmc1:0001:1                                                                                                                                               
     93 root       1 -19       0      0      0 S   0.7   0.0   1:15.56 vchiq-slot/0                                                                                                                                                                    
   1474 mark      20   0   10080   3360   2616 S   0.7   0.0   0:02.58 top                                                                                                                                                                             
   1491 root      20   0       0      0      0 I   0.7   0.0   0:00.56 kworker/0:1-events                                                                                                                                                              
   1574 mark      20   0    9988   2944   2404 R   0.7   0.0   0:00.15 top

[marksutheran]

FYI, continuing the quick test - without any special tuning the following configs work as follows and I suspect give an idea about the h/w encoding limits

Both cams 1920x1080 @ 20fps - stable streaming over WiFi for 2+ hours
Both cams 1080x720 @ 30fps - stable
One cams 1080x720 @ 30fps, one cam 1920x1080 @ 30fps - stable
Both cams 1920x1080 @ 25fps - unstable with the following error:
Both cams 1920x1080 @ 30fps - (more) unstable with the following error:

encoder_encode(): ioctl(VIDIOC_QBUF) failed
encoder_encode(): ioctl(VIDIOC_QBUF) failed
encoder_encode(): ioctl(VIDIOC_QBUF) failed

[marksutheran]

Both cams running continuous stream via WebRTC for 20 hours - no issues noticed.

[aler9]

added in v0.22.0