Re: Getting a hook from shell mode to do motion detection?

Hi,

Order of -l components is important and you need to add -lgphoto2_port, e.g. like:


gcc -Wall -o pb sample-photobooth.c -L/usr/local/bin/gphoto2-2.5.15/lib -lgphoto2 -lgphoto2_port

Ciao, Marcus

On Sun, Dec 31, 2017 at 07:39:01PM -0500, Alan Corey wrote:
> Well, I haven't had a lot of luck getting things from the
> libgphoto2/examples dir running so I gave up.  Just recently I tried
> copying sample-photobooth.c (and samples.h) into an empty dir and
> compiling with a makefile that looks like
> 
> -------------
> pb: sample-photobooth.c
>         gcc -Wall -o pb -lgphoto2 sample-photobooth.c \
>   -L/usr/local/bin/gphoto2-2.5.15/lib
> 
> # lib path is because I didn't want it to conflict with debs gphoto
> # it's where libgphoto2.so.6.0.0  is
> --------------
> 
> And I get errors like:
> upstairs# make
> gcc -Wall -o pb -lgphoto2 sample-photobooth.c \
>   -L/usr/local/bin/gphoto2-2.5.15/lib
> /usr/bin/ld: /tmp/ccBGh1Jj.o: undefined reference to symbol
> 'gp_log_add_func@@LIBGPHOTO2_5_0'
> //usr/local/bin/gphoto2-2.5.15/lib/libgphoto2_port.so.12: error adding
> symbols: DSO missing from command line
> collect2: error: ld returned 1 exit status
> Makefile:2: recipe for target 'pb' failed
> make: *** [pb] Error 1
> 
> I did an ldconfig on the path where the library is.  I was also
> getting the "DSO missing from command line" error trying to build
> preview.c.  I've never seen it on anything I wrote, trying to google
> it wasn't very productive.
> 
> On 12/31/17, Marcus Meissner <[email protected]> wrote:
> > Hi,
> >
> > If you want to do this all with one camera you might be better of writing
> > a program using libgphoto2, either in C or Python.
> >
> > FWIW, I did something similar to Tomas btw.
> >
> > Setup:
> >
> > - Cheap Webcam
> > - Canon EOS 1000D with AC adapter.
> > - Laptop
> >
> > Then I ran the "motion" tool using the webcam.
> >
> > The "motion" tool has hooks where it can callout to shell scripts.
> > I wrote a simple shell script that ran gphoto2 --capture-image-and-download
> >
> > and hooked it to the motion detection hook.
> >
> > It needed some checking that it does not run it twice (because
> > if there is motion it would trigger faster than capturing)
> > and it runs the disk full quite quickly with DSLR sized images.
> >
> > Ciao, Marcus
> >
> >
> > On Sat, Dec 30, 2017 at 02:06:13PM -0500, Alan Corey wrote:
> >> I've been thinking about this.  I plan to write in C, and between
> >> system() and popen() and pipe() and etc there's probably a way to do
> >> it.  From a console you type shell and give commands, then you can
> >> type more commands.  But I'm not sure how a program would do that: as
> >> a file descriptor or a pipe (or a socket) (dbus?)?  Gphoto as a
> >> process stays running, you just need a programmatic way to communicate
> >> with it.  The looping and branching wouldn't happen in Gphoto's shell,
> >> that would be more like a low level server or driver.  I could of
> >> course modify my copy of the source but I'd rather not do that.  I was
> >> about to experiment a bit until I found my oldschool loadjpeg function
> >> evidently doesn't work under Linux, I need to make a Turbo Jpeg
> >> equivalent.  Or maybe I still need some dev file or header.  Wacky, it
> >> doesn't know jpeg_CreateDecompress or what a size_t is?  I wrote it
> >> under OpenBSD a couple years ago, it's been reasonably portable until
> >> now.  Loading a straight uncompressed RGB binary would be optimum but
> >> I need to decompress jpegs.  Don't know yet if I can send to stdout.
> >>
> >> I ran across motion last night but didn't bother to install it.  I
> >> think it's strictly V4L so it's low quality just because the cameras
> >> are.  I've got a 640x480 USB webcam that does V4L but I'd rather not
> >> use it.  My motion detection scheme comes partly from a D-Link IP cam,
> >> that also only does 640x480.  I'll probably be running this on a
> >> Raspberry Pi, and I've got a few of those cameras, but I'd rather not
> >> use them.
> >>
> >> The standard Gphoto --capture-preview or the shell equivalent gets me
> >> a 320x240 jpeg which, if I decompress and compare in C, not something
> >> awful like Python, should be fast enough.  I'd rather not use 2
> >> cameras.  I'm from the Nikon camp, new to Canons for this project.
> >> For $20 used I got a 7 MP camera that not only works with Gphoto but
> >> also shoots RAW, most low-end Nikons won't do either.  I'm not
> >> sticking my D5200 DSLR in a birdfeeder.
> >>
> >> Shell mode is good for this because there's only 1 start-up time, the
> >> delay between pictures can be much lower than if you call Gphoto in a
> >> loop to start from scratch each time.  1 frame per second might be
> >> adequate but I'm aiming at 10.  CPU time on a Pi 3 comes cheap since
> >> it runs on a watt or two.  So I don't need to compare 320x240 images
> >> but if I can do it efficiently I can live with it.
> >>
> >> On 12/30/17, Tomas Alonso <[email protected]> wrote:
> >> > El Viernes, 29 de diciembre de 2017 17:39:08 Alan Corey escribió:
> >> >> I want to set up a wildlife camera, so I've read a few articles about
> >> >> it.  I've been practicing with an old Canon PowerShot S70 and it seems
> >> >> suitable.  What I'd like to try to do is use the preview images for
> >> >> motion detection.  I need to mask out some areas to avoid false
> >> >> activations from clouds passing over, that sort of stuff, and probably
> >> >> some averaging to account for the sun rising and setting.
> >> >>
> >> >> For speed it seems advisable to work in Gphoto2's shell mode but I'm
> >> >> trying to figure out a way to provide input from an external program.
> >> >> I want to do capture-preview in a loop: get a preview, run my compare
> >> >> program, get another preview.  If the compare sees something go into
> >> >> another loop grabbing big images for some amount of time, then back to
> >> >> previews.
> >> >>
> >> >> I did help in shell mode but I don't see anything listed that looks
> >> >> like it would work, like being able to detect the presence of some
> >> >> file I could use a a semaphore.  There aren't any branch (or loop)
> >> >> instructions either.
> >> >>
> >> >>   Alan
> >> >
> >> > Hello Alan,
> >> >
> >> > For other needs related to security I'm also interested in doing
> >> > something
> >> > equivalent. I thought my first try would be
> >> >
> >> > http://www.chriswpage.com/2009/05/setup-an-advanced-webcam-security-system-with-ubuntu-8-04-and-motion/
> >> >
> >> > using the motion program under Linux. It allows to launch scripts when
> >> > motion
> >> > is detected, but you need a webcam for motion detection and a camera
> >> > for
> >> > good
> >> > quality shots. That's (and the fact I own a Canon 40D) why I'm not sure
> >> > at
> >> > all
> >> > about the webcam approach.
> >> >
> >> > I have high programming skills and experience with gphoto so to
> >> > implement
> >> > this
> >> > myself will not be a problem. If you can't find a solution for your
> >> > case
> >> > just
> >> > send me the exact gphoto commands you use for your camera to enter
> >> > shell
> >> > mode,
> >> > take a preview, and take also a big image in auto mode or whatever you
> >> > use
> >> > (including the file names generated in your computer after executing
> >> > those
> >> > commands).
> >> >
> >> > Can't promise to do it for a given date but likely it will take few
> >> > weeks.
> >> >
> >> > Regards,
> >> > Tomas.
> >> >
> >> >
> >> > ------------------------------------------------------------------------------
> >> > Check out the vibrant tech community on one of the world's most
> >> > engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> >> > _______________________________________________
> >> > Gphoto-user mailing list
> >> > [email protected]
> >> > https://lists.sourceforge.net/lists/listinfo/gphoto-user
> >> >
> >>
> >>
> >> --
> >> -------------
> >> No, I won't  call it "climate change", do you have a "reality problem"? -
> >> AB1JX
> >> Impeach  Impeach  Impeach  Impeach  Impeach  Impeach  Impeach  Impeach
> >>
> >> ------------------------------------------------------------------------------
> >> Check out the vibrant tech community on one of the world's most
> >> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> >> _______________________________________________
> >> Gphoto-user mailing list
> >> [email protected]
> >> https://lists.sourceforge.net/lists/listinfo/gphoto-user
> >
> 
> 
> -- 
> -------------
> No, I won't  call it "climate change", do you have a "reality problem"? - AB1JX
> Impeach  Impeach  Impeach  Impeach  Impeach  Impeach  Impeach  Impeach

------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot