4 ms·

I wish they would finally expose the data lines for the second camera in their "hobbyist" boards as well. Currently the dual camera setup is supported only by C

by Yaggo 9y ago

I wish they would finally expose the data lines for the second camera in their "hobbyist" boards as well. Currently the dual camera setup is supported only by Compute Module, but it's cumbersome to use because the bulky I/O board (and expensive). The foundation is overlooking the most unique feature of the Broadcom chipset, the 3D video support. They already have implemented the software/driver side, so only thing required is just exposing the pins from the SOC and adding second camera connector – very low hanging fruit. (The Zero board may not have enough space for routing but the bigger boards definitely have.)

titchard 9y ago
That is interesting, I didn't even know that was a feature that was capped on the RPi. I can see that being made into very compact 3D Scanners very quickly after launch if that was added as a feature.
- Yaggo 9y ago
  To clarify, the "3D video feature" is nothing more than being able to record simultaneously from two cameras and merge the video inputs into side-by-side H264 stream. Combined with hardware H264 encoding with delay of ~100 ms, this is very useful for certain applications (in my case, live 3D video broadcasting from UAV). I'm not aware of any other "tinkerer-friendly" board capable of that.
  - imtringued 9y ago
    The hardware accelleration for H264 sounds interesting. Although 100ms is not as ideal as I want but it's reasonable. Is it actually possible to use this feature in practice? Are proprietary drivers an issue? Also is it possible to browse the web and e.g. watch videos on youtube with adequate performance on an RPi? (different topic)
    - Yaggo 9y ago
      > Is it actually possible to use this feature in practice? Are proprietary drivers an issue? I've streamed 3D video over wifibroadcast¹ to OSVR headset, no fundamental issues. The exact lag depends on resolution, fps, etc settings. It would be superb to cut the delay to sub-50 ms range, but that's probably not going to happen as it would require major rewrite of the H264 stack, as currently there are always two full frames in the pipeline, e.g. in 30 fps it makes 1000/30*2 -> ~70 ms delay². (Note that I'm not the author of the befinitiv website.) The foundation has released open-source driver stack³ (raspivid etc), but AFAIK they have rather limited resources for software development (single ex-broadcom developer?) and limited access to proprietary features (documentation?) of the Broadcom chipset. Many things work but I think the capabilities of the SOC aren't yet fully utilized. > Also is it possible to browse the web and e.g. watch videos on youtube with adequate performance on an RPi? (different topic) No personal experience, but RPi 3 should be okayish for lightweight desktop use (YMMV) with 1 GB of RAM being main limitation for multitasking. [1] https://befinitiv.wordpress.com/wifibroadcast-analog-like-transmission-of-live-video-data/ https://befinitiv.wordpress.com/wifibroadcast-analog-like-tr... [2] https://befinitiv.wordpress.com/2015/09/10/latency-analysis-of-the-raspberry-camera/ https://befinitiv.wordpress.com/2015/09/10/latency-analysis-... [3] https://github.com/raspberrypi/userland https://github.com/raspberrypi/userland
  - cr0sh 9y ago
    I'm thinking something like this could be used for a depth sensing application; a visual rangefinder.
Greg-J 9y ago
I went from never soldering circuitry or working with a schematic to designing a PCB (the CMIO schematics are freely available and easy to reverse engineer even for someone with very limited knowledge), having it printed, and build it myself using 0603 and 0805 SMD components. It's really not that hard or expensive to do it yourself, and it's a fun little side project. Try it out.

by Yaggo 9y ago

titchard 9y ago

That is interesting, I didn't even know that was a feature that was capped on the RPi. I can see that being made into very compact 3D Scanners very quickly after launch if that was added as a feature.

Yaggo 9y ago
To clarify, the "3D video feature" is nothing more than being able to record simultaneously from two cameras and merge the video inputs into side-by-side H264 stream. Combined with hardware H264 encoding with delay of ~100 ms, this is very useful for certain applications (in my case, live 3D video broadcasting from UAV). I'm not aware of any other "tinkerer-friendly" board capable of that.
- imtringued 9y ago
  The hardware accelleration for H264 sounds interesting. Although 100ms is not as ideal as I want but it's reasonable. Is it actually possible to use this feature in practice? Are proprietary drivers an issue? Also is it possible to browse the web and e.g. watch videos on youtube with adequate performance on an RPi? (different topic)
  - Yaggo 9y ago
    > Is it actually possible to use this feature in practice? Are proprietary drivers an issue? I've streamed 3D video over wifibroadcast¹ to OSVR headset, no fundamental issues. The exact lag depends on resolution, fps, etc settings. It would be superb to cut the delay to sub-50 ms range, but that's probably not going to happen as it would require major rewrite of the H264 stack, as currently there are always two full frames in the pipeline, e.g. in 30 fps it makes 1000/30*2 -> ~70 ms delay². (Note that I'm not the author of the befinitiv website.) The foundation has released open-source driver stack³ (raspivid etc), but AFAIK they have rather limited resources for software development (single ex-broadcom developer?) and limited access to proprietary features (documentation?) of the Broadcom chipset. Many things work but I think the capabilities of the SOC aren't yet fully utilized. > Also is it possible to browse the web and e.g. watch videos on youtube with adequate performance on an RPi? (different topic) No personal experience, but RPi 3 should be okayish for lightweight desktop use (YMMV) with 1 GB of RAM being main limitation for multitasking. [1] https://befinitiv.wordpress.com/wifibroadcast-analog-like-transmission-of-live-video-data/ https://befinitiv.wordpress.com/wifibroadcast-analog-like-tr... [2] https://befinitiv.wordpress.com/2015/09/10/latency-analysis-of-the-raspberry-camera/ https://befinitiv.wordpress.com/2015/09/10/latency-analysis-... [3] https://github.com/raspberrypi/userland https://github.com/raspberrypi/userland
- cr0sh 9y ago
  I'm thinking something like this could be used for a depth sensing application; a visual rangefinder.

Greg-J 9y ago

I went from never soldering circuitry or working with a schematic to designing a PCB (the CMIO schematics are freely available and easy to reverse engineer even for someone with very limited knowledge), having it printed, and build it myself using 0603 and 0805 SMD components. It's really not that hard or expensive to do it yourself, and it's a fun little side project. Try it out.