Camera Support about nerves_system_rpi4 HOT 6 CLOSED

iex(1)> Picam.Camera.start_link            
{:error, {:already_started, #PID<0.1630.0>}}
iex(2)> File.write!(Path.join(System.tmp_dir!, "frame.jpg"), Picam.next_frame)
** (exit) exited in: GenServer.call(Picam.FakeCamera, :next_frame, 5000)
    ** (EXIT) no process: the process is not alive or there's no process currently associated with the given name, possibly because its application isn't started
    (elixir 1.10.4) lib/gen_server.ex:1013: GenServer.call/3

bcm2835-v4l2: V4L2 device registered as video0 - stills mode > 1280x720
bcm2835-v4l2: Broadcom 2835 MMAL video capture ver 0.0.2 loaded.

iex> Application.stop(:camera)
iex> Application.stop(:picam) 
iex> System.cmd("/usr/bin/raspistill", ["-v", "-o", "/tmp/image.jpg"], stderr_to_stdout: true)

{"\"raspistill\" Camera App (commit 42df6e3e571c)
Camera Name ov5647
Width 2592, Height 1944, filename /tmp/image.jpg
Using camera 0, sensor mode 0
GPS output Disabled
Quality 85, Raw no
Thumbnail enabled Yes, width 64, height 48, quality 35
Time delay 5000, Timelapse 0
Link to latest frame enabled  no
Full resolution preview No
Capture method : Single capture
Preview Yes, Full screen Yes
Preview window 0,0,1024,768
Opacity 255
Sharpness 0, Contrast 0, Brightness 50
Saturation 0, ISO 0, Video Stabilisation No, Exposure compensation 0
Exposure Mode 'auto', AWB Mode 'auto', Image Effect 'none'
Flicker Avoid Mode 'off'
Metering Mode 'average', Colour Effect Enabled No with U = 128, V = 128
Rotation 0, hflip No, vflip No
ROI x 0.000000, y 0.000000, w 1.000000 h 1.000000
Camera component done
Encoder component done
Starting component connection stage
Connecting camera preview port to video render.
Connecting camera stills port to encoder input port
Opening output file /tmp/image.jpg
Enabling encoder output port
Starting capture -1
Finished capture -1
Closing down
Close down completed, all components disconnected, disabled and destroyed",
 0}