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Paired cameras for stereoscopic enhancement

morgaine

Has anyone reported yet their use of two Pi cameras slaved together as a binocular pair and the output being  processed in one of the many ways available for stereoscopy or 3D  imaging?

 

In addition to the above, I was pondering ways to combine such a pair of still images or video streams with those forthcoming CastAR 3D glasses that we were talking about a little while ago, hopefully produced one day by Jeri Ellsworth's Technical Illusions outfit --- HackADay has a brief description of the technology (see Youtube and The Amp Hour for a lot more).

 

Since  the retro-reflective screen happily sends back anything projected at it from each eye's vantage point, it should require no processing at all to view the output from dual cameras in full glorious 3D in CastAR, other than maybe format conversion.  Given the low price of the Pi camera, this is sure to happen the instant the glasses become available.

 

(I  was also wondering how the eye/brain combination would perceive the effect of dramatically increasing the separation between the two cameras when used with CastAR --- that's sure to be interesting, as it will allow parallax to be increased artificially beyond human range.)

 

And going even further, processing the dual images or streams for contrast enhancement or to pick out other desireable visual properties is sure to be of interest in many areas, microscopy being just one.

 

Morgaine.

Parents

  • Did you see this ?

    http://www.raspberrypi.org/archives/3376

     

    as noted, likely the biggest problem will be a lack of synchronisation capability. 

     

    I think you're spot on that the low price changes things and opens up use cases you couldn't otherwise consider.  However, if you spend even five mins in the RPF forums camera subsection it's quickly clear that the lack of control over what the GPU really does is a problem as you can't guarantee the two cameras will do the same thing when looking at the same image.   There are lots of people with interesting ideas that the RPF had never thought of, which is exactly as you'd expect, but the lack of a certain level of control is making some things difficult.

     

    Some posts in another thread from 'gsh' suggests that there may be the possibility of getting direct access to the CSI from the Arm if Broadcom will let them document it. Presumably at that point you'll have much more control, even if it does become a case of simply dumping the data for processing later.

  • in reply to Former Member

    Thanks for the link.  Cool, so there is a  bit of activity ongoing with dual cameras, Gordon's MicroDB and the work done by Maximum PC magazine.  There's sure to be much more soon I think.

     

    Regarding lack of control over the CSI and the GPU, what software control do users have currently over the camera module?

     

    PS. I couldn't perceive any extra depth  on that stereo video using red/green glasses, nor any feeling of nausea.  I suspect it's just due to the terribly shaky capture though, which I find extremely annoying as I can't focus on anything.  I look forward to watching some smoothly filmed 3D content.

  • in reply to morgaine

    Morgaine Dinova wrote:

     

    Regarding lack of control over the CSI and the GPU, what software control do users have currently over the camera module?

    Not as much as they'd like is probably a fair assesment.

     

    The parameters for the raspistill prog are as follows

     

    Image parameter commands

     

    -sh, --sharpness        : Set image sharpness (-100 to 100)

    -co, --contrast : Set image contrast (-100 to 100)

    -br, --brightness       : Set image brightness (0 to 100)

    -sa, --saturation       : Set image saturation (-100 to 100)

    -ISO, --ISO     : Set capture ISO

    -vs, --vstab    : Turn on video stablisation

    -ev, --ev       : Set EV compensation

    -ex, --exposure : Set exposure mode (see Notes)

    -awb, --awb     : Set AWB mode (see Notes)

    -ifx, --imxfx   : Set image effect (see Notes)

    -cfx, --colfx   : Set colour effect (U:V)

    -mm, --metering : Set metering mode (see Notes)

    -rot, --rotation        : Set image rotation (0-359)

    -hf, --hflip    : Set horizontal flip

    -vf, --vflip    : Set vertical flip

     

     

    Notes

     

    Exposure mode options :

    off,auto,night,nightpreview,backlight,spotlight,sports,snow,beach,verylong,fixedfps,antishake,fireworks

     

    AWB mode options :

    off,auto,sun,cloud,shade,tungsten,fluorescent,incandescent,flash,horizon

     

    Image Effect mode options :

    none,negative,solarise,sketch,denoise,emboss,oilpaint,hatch,gpen,pastel,watercolour,film,blur,saturation,colourswap,washedout,posterise,colourpoint,colourbalance,cartoon

     

    Metering Mode options :

    average,spot,backlit,matrix

    plus various stuff like what size, jpg/png, saved image quality etc.

     

    However some of these don't work (iso settings were only recently enabled) and some don't seem to do what's expected. For example there are reports of the GPU selecting low ISO and bright daylight like exposure times for night time images.

    Also reports that in timelapse mode the camera locks the ISO setting early and never changes it, or (and the reason I started watching the camera forum) that timelapse images of a bright outdoor scene gradually fade off to black over some minutes, but maybe only if you turn the preview mode off.

     

    Obviously still early days for the camera and things will get fixed, or new features added. However the stumbling block seems to be that jamesh is the only one with access to do any of the GPU side driver work and he doesn't seem to have time/motivation/something to work on it much. That's fair enough as he's just a volunteer doing it in his free time, but I think it's also why some people are interested in getting direct access without the GPU.

Reply
  • in reply to morgaine

    Morgaine Dinova wrote:

     

    Regarding lack of control over the CSI and the GPU, what software control do users have currently over the camera module?

    Not as much as they'd like is probably a fair assesment.

     

    The parameters for the raspistill prog are as follows

     

    Image parameter commands

     

    -sh, --sharpness        : Set image sharpness (-100 to 100)

    -co, --contrast : Set image contrast (-100 to 100)

    -br, --brightness       : Set image brightness (0 to 100)

    -sa, --saturation       : Set image saturation (-100 to 100)

    -ISO, --ISO     : Set capture ISO

    -vs, --vstab    : Turn on video stablisation

    -ev, --ev       : Set EV compensation

    -ex, --exposure : Set exposure mode (see Notes)

    -awb, --awb     : Set AWB mode (see Notes)

    -ifx, --imxfx   : Set image effect (see Notes)

    -cfx, --colfx   : Set colour effect (U:V)

    -mm, --metering : Set metering mode (see Notes)

    -rot, --rotation        : Set image rotation (0-359)

    -hf, --hflip    : Set horizontal flip

    -vf, --vflip    : Set vertical flip

     

     

    Notes

     

    Exposure mode options :

    off,auto,night,nightpreview,backlight,spotlight,sports,snow,beach,verylong,fixedfps,antishake,fireworks

     

    AWB mode options :

    off,auto,sun,cloud,shade,tungsten,fluorescent,incandescent,flash,horizon

     

    Image Effect mode options :

    none,negative,solarise,sketch,denoise,emboss,oilpaint,hatch,gpen,pastel,watercolour,film,blur,saturation,colourswap,washedout,posterise,colourpoint,colourbalance,cartoon

     

    Metering Mode options :

    average,spot,backlit,matrix

    plus various stuff like what size, jpg/png, saved image quality etc.

     

    However some of these don't work (iso settings were only recently enabled) and some don't seem to do what's expected. For example there are reports of the GPU selecting low ISO and bright daylight like exposure times for night time images.

    Also reports that in timelapse mode the camera locks the ISO setting early and never changes it, or (and the reason I started watching the camera forum) that timelapse images of a bright outdoor scene gradually fade off to black over some minutes, but maybe only if you turn the preview mode off.

     

    Obviously still early days for the camera and things will get fixed, or new features added. However the stumbling block seems to be that jamesh is the only one with access to do any of the GPU side driver work and he doesn't seem to have time/motivation/something to work on it much. That's fair enough as he's just a volunteer doing it in his free time, but I think it's also why some people are interested in getting direct access without the GPU.

Children
  • in reply to Former Member

    Great, thanks for the info!

     

    I've now also found the source repo for the camera utilities on Github, so I'll poke around with those when I get some time.  Time is in very short supply here just at the moment, and I haven't even powered on the model A that I want to run the camera, which is still in its anti-static bag.

     

    While BBB has leapfrogged almost all of the bullet points on Pi's features list, it's nice that Pi still has media centres (in which I'm not interested) and camera capability (in which I am, for microscopy) to enjoy as unrivalled applications.  I hope to put it to good use within a few months.

     

     

    Addendum:  So, the Pi camera interface is a bit like that for the GPU, just a thin open source but uninformative shim in the kernel which passes messages to the VideoCore which then pokes at the CSI interface?