IMX CSI

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Revision as of 22:29, 5 March 2018 by Admin (talk | contribs)

Before you start any of below pipeline make sure you have camera connected. IMX family of processor uses gstreamer as multimedia framework.

Please refer to https://gstreamer.freedesktop.org/

Run below command to see if you have got the camera detected

root@imx:~# v4l2-ctl --list-devices

This should output below

root@imx:~# 
i.MX6S_CSI (platform:30710000.csi):
        /dev/video1

pxp (pxp_v4l2_out):
        /dev/video0


As you can see above i.MX6S_CSI (platform:30710000.csi): is camera and pxp (pxp_v4l2_out): pixel procesing engine for overlay on display

Checking whether you have got the imx platform plugins installed on your filesystem: Run below command to check whether you have the IMX platform specific gstreamer plugin installed or not.

root@imx:~# gst-inspect-1.0  | grep "imx"
imxpxp:  imxpxpvideotransform: Freescale PxP video transform
imxpxp:  imxpxpvideosink: Freescale PxP video sink
imxv4l2videosrc:  imxv4l2videosrc: V4L2 CSI Video Source
imxaudio:  imxmp3audioenc: Freescale i.MX MP3 encoder
imxaudio:  imxuniaudiodec: Freescale i.MX uniaudio decoder
  • imxv4l2videosrc: is the IMX family CSI camera v4l2 community plugin. Currently devkits only supports OV5640 as YUV input.

where sensor process incoming light and converts it to YUV 4:2:2 format data. MIPI data is captured by the MIPI CSI input of the devkit. Bayer processing not supported.

Below pipelines are tested on latest yocto releases (rocko, morty, pyro)

Camera Preview on Display :

  • For 640x480@30fps:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=0 ! imxpxpvideosink
  • NTSC 720x480@30fps:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=1 ! imxpxpvideosink
  • 720P 1280x720@30fps :
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=2 ! imxpxpvideosink
  • For 1080P@30fps:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=3 ! imxpxpvideosink
  • For QSXGA 2592x1944@15fps:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=4 ! imxpxpvideosink


To Capture JPEG snapshot:

  • For 640x480:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=0 num-buffers=1 ! jpegenc ! filesink location=/tmp/test.jpg
  • NTSC 720x480:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=1 num-buffers=1 ! jpegenc ! filesink location=/tmp/test.jpg
  • 720P 1280x720:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=2 num-buffers=1 ! jpegenc ! filesink location=/tmp/test.jpg
  • For 1080P:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=3 num-buffers=1 ! jpegenc ! filesink location=/tmp/test.jpg
  • For QSXGA 2592x1944:
root@imx:~# gst-launch-1.0 imxv4l2videosrc device=/dev/video1  imx-capture-mode=4 num-buffers=1 ! jpegenc ! filesink location=/tmp/test.jpg


Please note : jpegenc is opensource software based jpeg encoder. This gets executed on CPU not using JPEG hardware acceleration. Transfer /tmp/test.jpg to your PC and see whether you got correct snapshot or not.

Some of the camera examples you may want to refer to :http://variwiki.com/index.php?title=VAR-SOM-MX6_GSTREAM, however please note, IMX7 has different multimedia capabilities.


For detailed camera training refer to : http://cache.freescale.com/files/training/doc/ftf/2014/FTF-CON-F0119.pdf