| Table of Contents | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
1. Emcraft OV5647 Camera
The i.MX 8MP NAVQ+ kit comes with support for connecting the Emcraft OV5647 camera. The OV5647 camera connects to the kit via the MIPI-CSI2 interface, and provides an easy way to bring visual input into the i.MX 8M Plus. The camera is based on the Omnivision OV5647 chip. It provides auto focus, focal length 2.8mm, range 60cm-infinity and an 62 degrees field-of-view. Link to the i.MX 8M Plus is via the dual-lane MIPI-CSI2 interface.
The OV5647 camera does not implement an ISP processing block on board, so video stream from the camera is transmitter in raw bayer format directly to the i.MX 8MP, where the stream is processed by the dedicated i.MX 8MP ISP block. The i.MX 8MP ISP processing pipeline includes de-mosaicing from the bayer format and 3A processing (Auto Exposure, Auto Focus, Auto White Balance).
2. Connecting Emcraft OV5647 Camera
To connect the Emcraft OV5647 camera to the kit, plug the camera cable into the CSI1 on the back side of the carrier board. The following picture illustrates connection of the camera to the kit:
...
3. Software Setup
For correct functioning of the Emcraft OV5647 camera with NAVQ+ kit BSP release 1.1.8-xxx or higher is required. To enable support for the camera in software follow the below steps that enable correct DTB configuration for Linux kernel:
...
After the last command is invoked the board will reset, and OV5647 camera will be ready for use on the CSI1 port.
4. Finding Camera Device Nodes
Depending on additional hardware connected to the NAVQ+, the Emcraft OV5647 camera may not be the only V4L2 device present in the system. In order to access the camera the user needs to determine the correct video device file node.
...
In the above output, the /dev/video3 device node corresponds to the camera connected to the CSI1 slot.
5. Streaming Video to HDMI Display
Use the “Cheese” program shipped as part of Gnome desktop environment for streaming video input from the OV5647 camera to the HDMI display connected to the NAVQ+:
...
At this point you should be getting GUI window with video stream displayed in real-time on your HDMI display:
...
6. Capturing Video Frames
Use the following Linux command to capture a single frame into a file:
...
| Code Block |
|---|
user@imx8mpnavq:~$ gst-launch-1.0 v4l2src device='/dev/video3' ! queue ! 'video/x-raw,widtgh=1920,height=1080' ! v4l2h264enc ! mpegtsmux ! filesink location=video.mp4 |
7. Known Problems and Limitations
White balance for the OV5647 camera in 1080p mode has slight deviation to green tint. This is caused by not optimal ISP pipeline configuration, which will be fixed in future releases.