Template:FriendlyCoreAllwinner-DVPCam

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Connect to DVP Camera CAM500B

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

The mjpg-streamer application is an open source video steam server. After it is successfully started the following messages will be popped up:

 
 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
mjpg-streamer是用libjpeg对摄像头数据进行软编码,Linux-4.x内核的ROM目前并不支持视频硬编码, 但是如果使用Linux-3.x内核的ROM的话, 则可以使用ffmpeg对摄像头数据进行硬编码,这样能大大降低CPU的占用率并提高编码速度:

$ 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.