Richard, Please see the post http://blog.lemoneerlabs.com/post/BBB-webcamsconcerning the PS3Eye, C920, and frame rates. I believe it will answer your questions.
On Tue, Sep 24, 2013 at 12:50 PM, rh_ <[email protected]> wrote: > On Mon, 23 Sep 2013 01:48:18 -0700 > Michael Darling <[email protected]> > wrote: > > > I have confirmed that it is indeed possible to grab AND convert > > frames at 640x480 and 30 fps with the BBB and Logitech C920 operating > > The ps3 eye could not do this or have you tried yet? > > > in MJPEG mode. My solution was to basically install libjpeg-turbo > > from source with NEON enabled and then building and installing OpenCV > > from source, using libjpeg-turbo as the JPEG codec. I also built > > OpenCV with NEON enabled. > > > > Here is sample output with every frame being processed. The 'top' > > utility shows about 50% CPU and only about 2% memory usage. Before > > executing the code, I set the CPU to operate at constant 1Ghz using > > "sudo cpufreq-set -g performance" so that there isn't a "slow start" > > while the BBB starts grabbing frames at 300 Mhz before it finally > > kicks into 1Ghz under load. > > > > time ./framegrabber -f mjpeg -H 480 -W 640 -c 1000 -I 30 -o > > Startup took 0.000000 seconds > > Captured 1000 frames and Processed 1000 in 13.940000 seconds > > Shutdown took 0.010000 seconds > > > > > > real 0m33.760s > > user 0m11.566s > > sys 0m2.518s > > > > I ended up using distcc to do a distributed cross-build of OpenCV on > > my PC, but still had problems with running out of space trying to > > store all of the source and object files on the 2GB eMMC on the BBB. > > I ended up having to mount an ext2 formatted filesystem using a USB > > thumb drive hooked up to the BBB and building OpenCV from there. I > > probably ended up doing a lot of extraneous things that had little to > > no effect but I do have a working process for those who need to get > > 30 fps. I need to go back and clean up some notes I took and then I > > plan to post a step-by-step guide for anybody else who wants to > > replicate what I did. > > Will you say what the application is? Or at least is it a stationary > camera? Or is it something like for robot vision? Using that Motion > app (mentioned previously) would get higher frame-rate, I think. > Unless Motion is post-processing. I'm sure not all USB cams are > created equal. But I wonder how much can be done via USB. > Seems to me that image substraction (or whatever the correct term) > would probably need to happen at the hardware level to get any > capture rate increase. So maybe there's no way to get a higher > frame rate due to hardware limitations. > > > > > Thanks, > > -Mike > > > > > > On Sat, Sep 21, 2013 at 4:48 PM, Matthew Witherwax > > <[email protected]>wrote: > > > > > Jon, > > > > > > I hope you find it useful. I would appreciate any feedback you > > > have to give. > > > > > > Best of luck, > > > Matthew > > > > > > > > > On Sat, Sep 21, 2013 at 4:54 AM, <jescombe-gM/Ye1E23mwN > > > [email protected]> wrote: > > > > > >> Matthew, > > >> > > >> Thanks! That may be really useful for me. Am messing around with a > > >> PTZ camera at the moment, and lag in the video stream has been a > > >> bit of a problem so far.. > > >> > > >> Regards, > > >> Jon > > >> > > >> > > >> On Friday, 20 September 2013 14:01:23 UTC+1, Matthew Witherwax > > >> wrote: > > >>> > > >>> William, > > >>> > > >>> I have posted my streaming code and writeup here > > >>> http://blog.lemoneerlabs.com/**post/bbb-mjpeg-streaming< > http://blog.lemoneerlabs.com/post/bbb-mjpeg-streaming> > > >>> > > >>> > > >>> -- > > >> For more options, visit http://beagleboard.org/discuss > > >> --- > > >> You received this message because you are subscribed to a topic in > > >> the Google Groups "BeagleBoard" group. > > >> To unsubscribe from this topic, visit > > >> https://groups.google.com/d/topic/beagleboard/G5Xs2JuwD_4/unsubscribe > . > > >> To unsubscribe from this group and all its topics, send an email to > > >> beagleboard+unsubscribe-/JYPxA39Uh5TLH3MbocFF > > >> +G/[email protected] For more options, visit > > >> https://groups.google.com/groups/opt_out. > > >> > > > > > > -- > > > For more options, visit http://beagleboard.org/discuss > > > --- > > > You received this message because you are subscribed to a topic in > > > the Google Groups "BeagleBoard" group. > > > To unsubscribe from this topic, visit > > > https://groups.google.com/d/topic/beagleboard/G5Xs2JuwD_4/unsubscribe. > > > To unsubscribe from this group and all its topics, send an email to > > > beagleboard+unsubscribe-/JYPxA39Uh5TLH3MbocFF > > > +G/[email protected] For more options, visit > > > https://groups.google.com/groups/opt_out. > > > > > > > -- > > For more options, visit http://beagleboard.org/discuss > > --- > > You received this message because you are subscribed to the Google > > Groups "BeagleBoard" group. To unsubscribe from this group and stop > > receiving emails from it, send an email to beagleboard > > [email protected]. For > > more options, visit https://groups.google.com/groups/opt_out. > > > -- > > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/G5Xs2JuwD_4/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
