MX8 CSI

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Revision as of 13:33, 11 November 2019 by Eran (talk | contribs)
Camera

Testing MIPI-CSI2 cameras

Make sure you have the camera(s) connected to the board before booting it and running any of the pipelines below .
The i.MX family of SOCs uses gstreamer as a multimedia framework. Please refer to https://gstreamer.freedesktop.org/

Camera Probe

Run the following command to list the detected camera devices

# v4l2-ctl --list-devices

On VAR-SOM-MX8 it should produce the following output

# v4l2-ctl --list-devices
vpu B0 (platform:):
        /dev/video12
        /dev/video13

mxc-isi (platform:58100000.isi.0):
        /dev/video0
        /dev/video1

mxc-jpeg decoder (platform:58400000.jpegdec):
        /dev/video2

mxc-jpeg decoder (platform:58450000.jpegenc):
        /dev/video3

There is one camera accessible as /dev/video0, attached to the VAR-EXT-CB8 expansion board.


On SPEAR-MX8 this should produce the following output:

# v4l2-ctl --list-devices
vpu B0 (platform:):
        /dev/video12
        /dev/video13

mxc-isi (platform:58100000.isi.0):
        /dev/video0
        /dev/video2

mxc-isi (platform:58140000.isi.4):
        /dev/video1

mxc-jpeg decoder (platform:58400000.jpegdec):
        /dev/video3

mxc-jpeg decoder (platform:58450000.jpegenc):
        /dev/video4

There are two cameras accessible as /dev/video0 and /dev/video1, both attached to the VAR-EXT-CB8 expansion board.

Testing Camera Preview on Display

In the examples below /dev/video1 can be used instead of /dev/video0 on boards with 2 cameras.

  • 480p (640x480):
# gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=640,height=480 ! autovideosink sync=false
  • NTSC (720x480):
# gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=720,height=480 ! autovideosink sync=false
  • 720p (1280x720):
# gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=1280,height=720 ! autovideosink sync=false
  • 1080p (1920x1080):
# gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=1920,height=1080 ! autovideosink sync=false
  • QSXGA (2592x1944):
# gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=2592,height=1944 ! autovideosink sync=false


Testing Camera JPEG Snapshot

To capture a JPEG snapshot run one of the pipelines below, depending upon the required picture resolution.
In the examples below /dev/video1 can be used instead of /dev/video0 on boards with 2 cameras.

  • 480p (640x480):
# gst-launch-1.0 v4l2src device=/dev/video0 num-buffers=1 ! video/x-raw,width=640,height=480   ! jpegenc ! filesink location=/tmp/test.jpg
  • NTSC (720x480):
# gst-launch-1.0 v4l2src device=/dev/video0 num-buffers=1 ! video/x-raw,width=720,height=480   ! jpegenc ! filesink location=/tmp/test.jpg
  • 720p (1280x720):
# gst-launch-1.0 v4l2src device=/dev/video0 num-buffers=1 ! video/x-raw,width=1280,height=720  ! jpegenc ! filesink location=/tmp/test.jpg
  • 1080p (1920x1080):
# gst-launch-1.0 v4l2src device=/dev/video0 num-buffers=1 ! video/x-raw,width=1920,height=1080 ! jpegenc ! filesink location=/tmp/test.jpg
  • QSXGA (2592x1944):
# gst-launch-1.0 v4l2src device=/dev/video0 num-buffers=1 ! video/x-raw,width=2592,height=1944 ! jpegenc ! filesink location=/tmp/test.jpg


Using 2 cameras simultaneously

The following pipeline is an example of using 2 cameras simultaneously.
In this example a short video stream from each camera is saved as an MJPEG-encoded AVI file.

# gst-launch-1.0 v4l2src device=/dev/video0 num-buffers=100 ! video/x-raw,width=1920,height=1080 ! jpegenc ! avimux ! filesink location=./test0.avi \
                 v4l2src device=/dev/video1 num-buffers=100 ! video/x-raw,width=1920,height=1080 ! jpegenc ! avimux ! filesink location=./test1.avi