Using motion as a camera proxy -- disabling recompression of jpeg images

Question

Hello!

I'd like to have motion acting as a camera proxy server, to aggregate mjpeg streams from various network and usb cameras to one server and view them from there. I've been testing motion with a stream from a network camera yesterday, and it appears to me that the program does recompression of received mjpeg stream before serving it via the built-in web server. Is this true, and if yes, can it be disabled in order to conserve cpu resources?

What i've tried is disabling printing of date and time in the lower right corner of the movie and setting picture quality to 100 percent to avoid recompression. Seemingly -- no results.

I know I can disable motion detection (since I want the program to simply proxy the streams it's receiving). The page i found is this one: http://www.lavrsen.dk/twiki/bin/view/Motion/MotionHttpAPI#Detection_Commands

Thanks for your replies in advance! And thanks for this wonderful program!

Vyacheslav.

Environment

Motion version:	3.2.11.1
ffmpeg version:	0.5
Libraries:	ffmpeg, mysql
Server OS:	Slackware Linux 13.0, kernel 2.6.29.6

-- VyacheslavStetskevych - 17 Dec 2009

Answer

It's no supported a passthru of stream without recompresing , however it could be a new feature.

-- AngelCarpintero - 21 Dec 2009

Next Question

Please, please, please add the stream passthru option to motion. It's a much needed feature for me now. I'm sure it'll come handy to many people afterwards.

The thing is, i'm pretty limited by system resources. I'm trying to build an embedded home server for various tasks, including serving mjpeg streams from 8 D-Link network video surveillance cameras. The projected computer will have an Intel Atom (around 1 GHz) and the stream recompression will pretty much eat it up.

While the passthru feature is not yet implemented, could you please tell me for now, what would be a minimum acceptable CPU for the following configuration (assuming motion is still recompressing the video stream):

- 8 MJPG network cameras, going at 320x240, around 5 fps output;

- 1 /dev/video0 camera via a pci or usb capture card (like a bt878-based one), at 320x240, 5 fps is a minimum, more would be great.

On a related note, can you recommend a small 1-port video capture adapter that works with linux?

Thank you very much.

-- VyacheslavStetskevych - 22 Dec 2009

---

Added this feature , get motion from svn ( revision 488 ) and apply the patch:

mkdir motion
cd motion
svn co -r488 http://www.lavrsen.dk/svn/motion/trunk/ .

patch -p0 < passthru-disable_detection.diff

autoconf ; ./configure ; make

Added a new patch adding a new option config disable_detection , allowing start motion with motion detection disable and no new to change from http ( detection to pause ),

with this new patch jpeg_passthru is not forcing pause of motion detection , you have the choice to do it with the new option config disable_detection.

-- AngelCarpintero - 25 Mar 2010