Lib[rem5|camera] to use everywhere

Hardware Librem 5
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No time to explain, just a new thread for discussion this post.

Few hours later… Sorry for early posting. Of course, I will explain everything in details. Let’s start from a short background.

As far as I know we have only one application (millipixels) that can take a photo in Librem5 and no other application can give an access to the camera (like decoder or firefox). The reason is that it uses libcamera api rather that standard v4l2. As a result, we have to use it directly and work with raw images (that millipixels does) or by some standartized wrapper, that all other application do. Pipewire is a such wrapper now, and it could be configured to work with video-only streams (to not break calls). So, the pipeline should look something like this: cam (front or back) → libcamera → pipewire → your app. Sounds quite simple but it does not work. At least it does not work in Byzantium and Crimson so far. I’m not sure about ‘Mobian’ and ‘pmOS’… But here, on Byzantium backports it takes much more time than I expected. Starting point is here.

  1. Linux kernel config must be patched to enable dmabuf heaps.
  2. libcamera must be patched to enable software postprocessing and built with gnutls to avoid isolation.
  3. wireplumber must be configured properly.

Finally, I was managed to put the whole puzzle together!
That is about this thread. Next I will present some details and put links here.

Content of this thread

  1. Checklist to share L5 cameras between apps
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Contain your excitement :slight_smile: Your topic and posts do not explain anything (the other one is way off topic too in that other thread). How about you edit the first post to tell everyone what it’s about, how its done and link to relevant sources…?

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Ball
Ball720×1440 45.6 KB

Just a ball. The most important thing is how this photo has been taken - by standard gnome Camera application through libcamera managed by pipewire! It means that the camera just became available almost everywhere! In all preinstalled/flatpaked/selfmade application! Just everywhere. So, lets start a new stage in Librem5 usability improvements :slight_smile:

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Yeah ok so this is a pretty big deal

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I must have less packages installed than you because it is not working for me and I have your backports installed

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I will push all necessary packages in a day :slight_smile:

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Sorry, you are right. I edited the first post to make it much more clear :innocent:

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Checklist to share L5 cameras between apps:

Note: I believe that you use the latest version of Byzantium or Crimson (not built yet) backports.

1. Cameras should be visible by the lib:

$ cam -l
[0:21:55.572391385] [3744]  INFO Camera camera_manager.cpp:327 libcamera v0.4.0
...
Available cameras:
1: Internal front camera (/base/soc@0/bus@30800000/i2c@30a40000/camera@20)
2: Internal back camera (/base/soc@0/bus@30800000/i2c@30a50000/camera@2d)

2. The library should be able to capture an image:

$ cam -c1 -C1
...
cam0: Capture 1 frames
1429.065381 (0.00 fps) cam0-stream0 seq: 000000 bytesused: 7970688

3. At this stage you should be able to grab video stream e.g. using gstreamer:

$ gst-launch-1.0 libcamerasrc camera-name="/base/soc@0/bus@30800000/i2c@30a40000/camera@20" saturation=5 ! video/x-raw,format=RGB,width=720, height=576,framerate=10/1 ! videoconvert ! queue ! fpsdisplaysink text-overlay=false

4. Wireplumber should see your cameras:

$ wpctl satus
PipeWire 'pipewire-0' [1.4.1, purism@pureos, cookie:3974875000]
 └─ Clients:
        33. WirePlumber (video-only)            [1.4.1, purism@pureos, pid:1235]
        41. WirePlumber (video-only) [export]   [1.4.1, purism@pureos, pid:1235]
        56. xdg-desktop-portal                  [1.4.1, purism@pureos, pid:1500]
        57. xdg-desktop-portal-wlr              [1.4.1, purism@pureos, pid:2056]
        58. chatty                              [1.4.1, purism@pureos, pid:1878]
        59. wpctl 

Video
 ├─ Devices:
 │      42. imx-capture                         [v4l2]
 │      43. imx-capture                         [v4l2]
 │      44. nxp,imx8mq-vpu-g1-dec               [v4l2]
 │      45. nxp,imx8mq-vpu-g2-dec               [v4l2]
 │      46. hi846                               [libcamera]
 │      47. s5k3l6xx                            [libcamera]
 │  
 └─ Sources:
    *   52. Internal front camera
        54. Internal back camera

5. Grabbing used pipewire source also should work

path option is important, it must be equal your source id

$ gst-launch-1.0 pipewiresrc path=52 ! videoconvert ! video/x-raw,format=RGB,framerate=10/1 ! fpsdisplaysink text-overlay=false

6. Enjoy your cameras!

In fact - not. Just because a lot of options have not been realized yet (like autofocus) inside libcamera or realized not optimal.

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