Camarray – Arducam 2MP*2 Stereo Camera MIPI Module

Introduction

This Arducam 2MP*2 Stereo Camera MIPI Module is a stereo camera module with two synchronized monochrome global shutter OV2311 image sensors (2×2MP). It directly connects to the MIPI CSI-2 connectors of Raspberry Pi and Jetson Nano, and runs with a V4L2 camera driver on those platforms. It offers better flexibility to be integrated into your own hardware design or run with your own algorithm on embedded systems for applications like depth sensing, 3d mapping, SLAM, etc.

What is Camarray

Camarray is a series of embedded stereo cameras and multiple camera solutions from Arducam. Upgraded from Arducam Sync Stereo Camera HAT, the Camarry can disguise up to 4 synched camera modules as a single camera slot connection to embedded systems like the Raspberry Pi, Jetson nano, and Xavier NX. With Arducam camarray, your camera connectivities are no longer limited to the camera connectors on the motherboard or the carrier board. Along with Arducam-provided camera drivers, more flexibility can be added to your multi-camera applications.

Common Specs

Image sensor

Lens Assembly

Camera Board

Connector & Cable

Driver Performance (With Official V4L2 Driver)

Frame rates (adjustable: 5fps~50fps)

Quick Start Guide

Hardware Setup

Driver Installation

1.Driver note

There are 3 drivers for Raspberry Pi:

• Official driver
• Arducam MIPI camera driver
• Arducam V4L2 driver

1)Arducam MIPI camera driver is not in conflict with the official driver.

2)Arducam V4L2 driver is in conflict with the official driver. If you want to use the official driver, you need to uninstall the Arducam V4L2 driver first.

3)Arducam V4L2 driver is in conflict with Arducam MIPI camera driver. If you want to use the Arducam MIPI camera driver, you need to uninstall the Arducam V4L2 driver first.

4)Arducam V4L2 driver automatically overwrites the other two drivers. After uninstalling the Arducam V4L2 driver, it automatically reverts to the official driver.

The product is driven by the Arducam V4L2.

2.Check the driver

Check if the system is installed with the Arducam V4L2 driver.

sudo nano /boot/config.txt

Press【PageDown】several times or scroll your mouse wheel down to check if there is “dtoverlay=arducam”.

1)If you see “dtoverlay=arducam”, the Arducam V4L2 driver has been previously installed and is in a valid state.

2)If you see “#dtoverlay=arducam”, it means you have installed Arducam V4L2 driver before, but it is uninstalled now, remove the “#” to restore the V4L2 driver. Then reboot Pi to take effect.

3)If you don’t see “dtoverlay=arducam” or “#dtoverlay=arducam”, it means that Arducam’s V4L2 driver has never been installed before, so you need to follow the instructions below for a complete installation.

3. Install Arducam v4l2 driver

#Download driver package

wget https://github.com/ArduCAM/Arducam_OBISP_MIPI_Camera_Module/releases/download/v1.0/Release.tar.gz

#Extract the archive files

tar zxvf Release.tar.gz

#Enter the extracted folder

cd Release/

#Install the driver

./install_driver.sh

#Reboot the device

Press y, and then hit Enter to reboot.

Get an error?

If your operating system is not released by official Raspberry Pi, the driver installation will report an error and give a version error message.

Check out Raspberry Pi official supported operating system:

https://www.raspberrypi.org/software/operating-systems/

4. Uninstall the driver

Note that the driver will occupy CSI hardware resources. After installation, you will not be able to use the raspistill tool. There are two ways to uninstall Arducam V4L2 driver:

Method 1: Execute the uninstall command

cd Release/

./uninstall_driver.sh

Method 2: Modify configuration files

1.Type the following command:

sudo nano /boot/config.txt

2.Press【PageDown】several times or scroll your mouse wheel down to check if there is “dtoverlay=arducam”.

Modify “dtoverlay=arducam” as “#dtoverlay=arducam” to uninstall the V4L2 driver. Press 【Ctrl+X】, 【Y】,【Enter】to save the change and exit.

First Use

1.Check whether the camera is detected

ls /dev/video0

2.Check the video format supported

v4l2-ctl --list-formats-ext

At present, only “GREY” and “Y10P” formats are supported, and “Y10” format is not supported.

3.Preview the camera feed

#RAW10

arducamstill -t 0 -pixfmt Y10P -w 3200 -h 1300

#RAW8

arducamstill -t 0 -pixfmt GREY -w 3200 -h 1300

The last line shows frame in real time.

GREY for RAW8 and Y10P for RAW10.

​-w and -h indicate the width and height of the input image.

Press Ctrl+C to exit the preview.

4.Receive data without displaying the image

Dropped frames may exist due to platform performance. You can test the actual input frames by only receiving data without displaying the image.

#RAW8

v4l2-ctl --set-fmt-video=width=3200,height=1300,pixelformat='GREY' --stream-mmap --stream-count=-1 -d /dev/video0

#RAW10

v4l2-ctl --set-fmt-video=width=3200,height=1300,pixelformat='Y10P' --stream-mmap --stream-count=-1 -d /dev/video0

5.Adjust exposure

Open two terminals, the first one is for executing the displaying images command, the second one is for executing the adjusting exposure command.

#Adjust exposure:

v4l2-ctl -c exposure=1000

#Check exposure parameters (minimum, maximum, default)

v4l2-ctl -l

For example, execute the below command in the second terminal:

v4l2-ctl -c exposure=4000

Turning up the exposure time results in a brighter image and a lower frame rate.

6. Adjust gain

Open two terminals, the first one is for executing the displaying images command, the second one is for executing the adjusting gain command.

#Adjust gain:

v4l2-ctl -c gain=12

#Check exposure parameters (minimum, maximum, default)

v4l2-ctl -l

For example, execute the below command in the second terminal:

v4l2-ctl -c gain=200

Turning up the gain results in a brighter image and no change in frame rate.

7.Change frame rate

Type the following command, change the value of “X” to change frame rate.

v4l2-ctl -c frame_rate=X

For example, you want to change the frame rate to 35. First, open two terminals, type the following command in the first terminal:

arducamstill -t 0 -pixfmt GREY -w 3200 -h 1300

Type the following command in the second terminal to change frame rate:

v4l2-ctl -c frame_rate=35

Type the following command in the second terminal to view the frame rate range of the current display mode:

v4l2-ctl -l

IMPRORTANT NOTE

Dropped frames may exist due to the platform performance.

For example, if the frame rate is set to 50 fps, the display only goes up to 30fps.

But when you use only receiving data without displaying the image, the frame rate goes back to 50fps. (The frame rate values here are not real-time and are calculated iteratively with historical values, changing slowly.)

Display Images via VLC Media Player

You can display images in real time via the VLC media player.
(The VLC media player can only play images that are output in RAW8 format.)

1.Open VLC media plyer

2.Select 【Media】→【Open Capture Device…】

3.【Video device name】→ select “/dev/video0“→ click 【Play】.

It may be stuck due to Raspberry Pi performance and VLC media player.

4.Adjust the exposure, gain, and frame rate

【Tool】→【Effects and Filters】

Drag the different slider to adjust the corresponding parameter.

Display Images via Mplayer

1.Install mplay

sudo apt-get install mplayer

2.Display images

mplayer tv:// -tv driver=v4l2:device=/dev/video0

Do not enter this command remotely, otherwise it will be stuck.

The image screen may be too large for the display to be complete. You need to drag the title bar to move the window to see the full image.

Right-click on the mplayer title bar and select 【Maximize】. Then you can see see the full image. (The image is pretty smooth.)

Or enter the following command to zoom the image. The image will appear full, but it will become stuck.

mplayer tv:// -tv driver=v4l2:device=/dev/video0 -zoom -x 1600 -y 650

“-x” “- y” denotes the width and height of the scaled image, and it is recommended to modify them in equal proportion.

What’s Next

Here are the things you can do after this quick start:

• Check the Application Note for applications like using Arducam userland MIPI camera drivers.
• Join the discussion in our forum.

Application Note

Depth Mapping on Raspberry Pi

1.Install Driver

Please refer to this page for a driver demonstration.

2.Hardware Setup

3.Reboot RPi

After rebooting RPi, use ls /dev/video* command to see the video device.

4.Software Setup

4.1 Download the demo code

git clone https://github.com/ArduCAM/3d-camera.git

cd 3d-camera/stereo-camera/RaspberryPi/stereo_depth_demo/

4.2 Install Dependency for Python3.X

Latest Raspbian version is recommended.

sudo apt-get update && sudo apt-get install -y libhdf5-dev libhdf5-serial-dev libatlas-base-dev libjasper-dev libqtgui4 libqt4-test && sudo pip3 install opencv-python==3.4.6.27

sudo pip3 install stereovision

sudo pip3 install matplotlib

5.Run the Programs

5.1 Capture Images

python 1_test.py

Help message:

Example:

5.2 Collect Images for Calibration

python 2_chess_cycle.py

5.3 Separate Captured Images

python 3_pairs_cut.py

5.4 Calibration

python 4_calibration.py

5.5 Depth Map Tuning

python 5_dm_tune.py

5.6 Real-Time Depth Map Using Video

python 6_dm_video.py