In this guide, we will provide a step-by-step walkthrough on utilizing the OV5647 video camera on SP7350 platforms.
Contents
1. IMX219 Specification
The Raspberry Pi Camera Module 2 is used here. The pin definition of the SP7350 EV board’s MIPI-CSI RX connectors is compatible with this camera. The camera mounts directly to our SP7350 EV board.
Back-illuminated CMOS image sensor Exmor RTM
2-wire serial communication circuit on chip
CSI2 serial data output (selection of 4lane/2lane)
Timing generator, H and V driver circuits on chip
CDS/PGA on chip
10-bit A/D converter on chip
Automatic optical black (OB) clamp circuit on chip
PLL on chip (rectangular wave)
High sensitivity, low dark current, no smear
Excellent anti-blooming characteristics
Variable-speed shutter function (1 H units)
R, G, B primary color pigment mosaic filters on chip
Max. 30 frame/s in all-pixel scan mode
Pixel rate: 280 [Mpixel/s] (All-pixels mode)
180 frame/s @720p with 2x2 analog (special) binning, 60 frame/s @1080p with V-crop
Data rate: Max. 755 Mbps/lane(@4lane), 912Mbps/Lane(@2lane)
2. Setup a SP7350 Platform
The Raspberry Pi Camera Module 2 is used here. The v2 Camera Module has a Sony IMX219 8-megapixel sensor. The pin definition of the SP7350 EV board’s MIPI-CSI RX connectors is compatible with this module. The module mounts directly to our SP7350 EV board.
2.1. Enable IMX219 Driver in Linux Kernel Configuration
Please follow the steps below.
Step 1: Enter kernel configuration
# cd ./linux/kernel # make menuconfig
Step 2: Selects sub-menus: Device Drivers > Multimedia support > Media ancillary drivers > Camera sensor devices
Step 3: Select Sony IMX219 sensor support and pressing <Y> includes. And then save and exit.
2.2. Modify Device-tree Source
Device-tree source files of SP7350 are located in linux/kernel/arch/arm64/boot/dts/sunplus/. Here lists all files for SP7350 boards:
Boards | Device-tree source files |
C3V-W EVB | sp7350-ev.dts |
Modify device tree source file to define IMX219 source for driver. We had added some compiler switches for IMX219 camera in the beginning of sp7350-ev.dts. These compiler switches are turned off by default. They are shown below. You can turn it on based on your usage. For example, if an IMX219 camera is connected to MIPI-CSI RX4 port, the compiler switch IMX219_IN4 should be turned on.
//#define IMX219_IN0 //#define IMX219_IN1 //#define IMX219_IN2 //#define IMX219_IN3 //#define IMX219_IN4 //#define IMX219_IN5
2.3. Compile and Burn
2.4. Connect Sensor Module
A Raspberry Pi Camera Module 2 is connected to MIPI/CSI-RX4 port on C3V-W board. It’s shown below.
2.5. Check
After the burning is completed, start the board. The probing logs for MIPI-CSI RX and VIN drivers can be found. It’s as follows. The video device video0 has been successfully registered.
[ 1.333642] sp-csi2 f8005480.csirx: 2 lanes found [ 1.338482] sp-vin f8005980.video: assigned reserved memory node mipicsirx@4f600000 [ 1.345864] imx219 0-0010: Consider updating driver imx219 to match on endpoints [ 1.353444] sp-vin f8005980.video: Device VIN8 registered as video0 [ 1.359496] sp-vin f8005980.video: SP VIN driver probed
After the system startup is completed, the video device video0 can be found.
~ # ls /dev/video0 /dev/video0
3. Test
The v4l2-ctl application is used here. v4l2-ctl is a command line tool for controlling video devices on Linux systems.
3.1. Display Video Device Information
Running ‘v4l2-ctl –all-device‘ command displays all information about the video device video0. The results are as follows.
~ # v4l2-ctl --all --device /dev/video0 Driver Info: Driver name : sp_vin Card type : SP_VIN Bus info : platform:f8005980.video Driver version : 5.10.201 Capabilities : 0xa5200001 Video Capture Read/Write Streaming Extended Pix Format Device Capabilities Device Caps : 0x25200001 Video Capture Read/Write Streaming Extended Pix Format Media Driver Info: Driver name : sp_vin Model : sunplus,sp7350-vin Serial : Bus info : platform:f8005980.video Media version : 5.10.201 Hardware revision: 0x00000000 (0) Driver version : 5.10.201 Interface Info: ID : 0x03000011 Type : V4L Video Entity Info: ID : 0x0000000f (15) Name : VIN8 output Function : V4L2 I/O Pad 0x01000010 : 0: Sink Link 0x02000013: from remote pad 0x1000003 of entity 'sp_csi2 f8005480.csirx' (Video Pixel Formatter): Data, Enabled Priority: 2 Video input : 0 (VIN8 output: ok) Format Video Capture: Width/Height : 640/480 Pixel Format : 'RG10' (10-bit Bayer RGRG/GBGB) Field : None Bytes per Line : 1280 Size Image : 614400 Colorspace : sRGB Transfer Function : sRGB YCbCr/HSV Encoding: ITU-R 601 Quantization : Full Range Flags : User Controls exposure 0x00980911 (int) : min=4 max=1759 step=1 default=1600 value=1600 horizontal_flip 0x00980914 (bool) : default=0 value=0 flags=modify-layout vertical_flip 0x00980915 (bool) : default=0 value=0 flags=modify-layout alpha_component 0x00980929 (int) : min=0 max=255 step=1 default=255 value=255 Image Source Controls vertical_blanking 0x009e0901 (int) : min=4 max=65055 step=1 default=1283 value=1283 horizontal_blanking 0x009e0902 (int) : min=2808 max=2808 step=1 default=2808 value=2808 flags=read-only analogue_gain 0x009e0903 (int) : min=0 max=232 step=1 default=0 value=0 red_pixel_value 0x009e0904 (int) : min=0 max=1023 step=1 default=1023 value=1023 green_red_pixel_value 0x009e0905 (int) : min=0 max=1023 step=1 default=1023 value=1023 blue_pixel_value 0x009e0906 (int) : min=0 max=1023 step=1 default=1023 value=1023 green_blue_pixel_value 0x009e0907 (int) : min=0 max=1023 step=1 default=1023 value=1023 Image Processing Controls pixel_rate 0x009f0902 (int64) : min=182400000 max=182400000 step=1 default=182400000 value=182400000 flags=read-only test_pattern 0x009f0903 (menu) : min=0 max=4 default=0 value=0 (Disabled) 0: Disabled 1: Color Bars 2: Solid Color 3: Grey Color Bars 4: PN9 digital_gain 0x009f0905 (int) : min=256 max=4095 step=1 default=256 value=256
3.2. List Supported Video Format and Resolution
Running ‘v4l2-ctl –list-format-ext’ command lists the supported video format and resolution of the video device vidoe0. The results are as follows.
~ # v4l2-ctl --list-formats-ext --device /dev/video0 ioctl: VIDIOC_ENUM_FMT Type: Video Capture [0]: 'RG10' (10-bit Bayer RGRG/GBGB) Size: Discrete 3280x2464 Size: Discrete 1920x1080 Size: Discrete 1640x1232 Size: Discrete 640x480 [1]: 'pRAA' (10-bit Bayer RGRG/GBGB Packed) Size: Discrete 3280x2464 Size: Discrete 1920x1080 Size: Discrete 1640x1232 Size: Discrete 640x480 [2]: 'RGGB' (8-bit Bayer RGRG/GBGB) Size: Discrete 3280x2464 Size: Discrete 1920x1080 Size: Discrete 1640x1232 Size: Discrete 640x480
3.3. Configure Camera
Running ‘v4l2-ctl –get-ctrl’ gets the value of the controls. Running ‘v4l2-ctl –set-ctrl’ sets the value of the controls. The results are as follows.
~ # v4l2-ctl --get-ctrl digital_gain digital_gain: 256 ~ # v4l2-ctl --set-ctrl digital_gain=2048 ~ # v4l2-ctl --get-ctrl digital_gain digital_gain: 2048
3.4. Capture Image
Running following command capture a RAW8 picture. The pixel format RGGB means 8-bit Bayer RGRG/GBGB.
~ # v4l2-ctl -d /dev/video0 --set-fmt-video=width=1920,height=1080,pixelformat=RGGB --stream-mmap=3 --stream-to=/root/imx219.raw --stream-count=1
The following is the description of these parameters.
-d <device>: Set video device
--set-fmt-video=width=<width>,height=<height>,pixelformat=<format>: Set image format
--stream-mmap <count>: The number of buffers to allocate. The default is 3.
--stream-to <file>: The captured image is saved to this file.
--stream-count <count>: How many images to capture.
4. Display Image
The PixelViewer application is used here. PixelViewer is an open source project based cross-platform image viewer. You can download it from it’s website.
https://carinastudio.azurewebsites.net/PixelViewer/
Use PixelViewer to open the image file ‘imx219.raw’. Please follow the steps below to configure PixelViewer.
Step 1: Set ‘Format’ to Byer Pattern (8-bit)
Step 2: Set ’Bayer pattern’ to RGGB (2x2)
Step 3: Set ‘Dimension (px)’ to 1920 x 1080
