Template:FriendlyCoreAllwinner-DVPCam

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Revision as of 06:03, 11 June 2018 by Tzs (Talk | contribs) (updated by API)

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对于H3系列的板子,CAM500B需配合Linux-3.4内核和Linux-4.16内核使用。
对于H5系列的板子,CAM500B需配合Linux-4.16内核使用。
Linux-4.16属于实验阶段的内核,需自行编译:https://github.com/friendlyarm/linux/tree/sunxi-4.16.y
The CAM500B camera module is a 5M-pixel camera with DVP interface. For more tech details about it you can refer to Matrix - CAM500B.
connect your H3 board to a CAM500B. Then boot OS, connect your board to a network, log into the board as root and run "mjpg-streamer":

$ cd /root/mjpg-streamer
$ make
$ ./start.sh

You need to change the start.sh script and make sure it uses a correct /dev/videoX node. You can check your camera's node by running the following commands:

$ apt-get install v4l-utils
$ v4l2-ctl -d /dev/video0 -D
Driver Info (not using libv4l2):
        Driver name   : sun6i-video
        Card type     : sun6i-csi
        Bus info      : platform:camera
        Driver version: 4.16.0
	...

The above messages indicate that "/dev/video0" is CAM500B's device node.The mjpg-streamer application is an open source video steam server. After it is successfully started the following messages will be popped up:

 
$ ./start.sh
 i: Using V4L2 device.: /dev/video0
 i: Desired Resolution: 1280 x 720
 i: Frames Per Second.: 30
 i: Format............: YUV
 i: JPEG Quality......: 90
 o: www-folder-path...: ./www/
 o: HTTP TCP port.....: 8080
 o: username:password.: disabled
 o: commands..........: enabled

In our case the board's IP address was 192.168.1.230. We typed 192.168.1.230:8080 in a browser and were able to view the images taken from the camera's. Here is what you would expect to observe:
mjpg-streamer-cam500a
The mjpg-streamer utility uses libjpeg to software-encode steam data. The Linux-4.x based ROM currently doesn't support hardware-encoding. If you use a H3 boards with Linux-3.4 based ROM you can use the ffmpeg utility to hardware-encode stream data and this can greatly release CPU's resources and speed up encoding:

$ ffmpeg -t 30 -f v4l2 -channel 0 -video_size 1280x720 -i /dev/video0 -pix_fmt nv12 -r 30 \
        -b:v 64k -c:v cedrus264 test.mp4

By default it records a 30-second video. Typing "q" stops video recording. After recording is stopped a test.mp4 file will be generated.