Best video setup for this experiment?

[Jason Jackson]

Hi everyone, I am working on a science experiment that has run into a road block regarding the video camera setup.

The project I am working on deals with neuroplasticity (the ability of the brain to adapt) and the intriguing idea that the mind can learn to see with sound. The sounds are created by remapping video data as audio files and playing that sound back. Similar studies are currently being done with this as seen here: Auditory Displays for the Blind

For the experiment I need a head mounted video camera that would be the replacement for the blind participant's eyes (a forehead mounted camera ideally) that will have a live, real time video feed viewable on a laptop computer. Software on the computer will be doing work on this video feed.

The best camera I could find for this was the GoPro Hero3 Black edition because it comes close to human vision (170 degree field of view) and does well with changing lighting conditions. My only problem is that it has no way (that I could find) to have a real time video feed on the computer.

Have you any ideas how to tackle this problem?

edit:
Just to clarify, I need:
- head mounted camera that has 170 degree field of view that can have a live real time feed on a laptop

[Bill Davis]

The entire GoPro line has a video/audio out port via 3.5" mini pin. So that's one way to get a real time display.

If you add a WiFi back to the unit, you can get a wireless real time display, but it's typically not a full raster full frame rate process since it has to encode the signal to wi-fi to transmit it.

For a scientific proof of concept, I'd just go with the hardwired option.

BTW, "does well with changing lighting conditions" will prove to be very relative.There's no system at any price that can do what the human eye/brain link can do to sort out aperture/focus issues in a real-time situation.

FWIW.

[Jim Michael]

I would look at a machine vision, industrial, or security camera which have a direct output like you describe. Video cameras like the GoPro are mainly intended for recording to media so you would most likely be paying for capability you don't need. Also, the cameras lacking those features are going to be lighter and smaller.

[David Heath]

Originally Posted by Jason Jackson

The best camera I could find for this was the GoPro Hero3 Black edition because it comes close to human vision (170 degree field of view) and does well with changing lighting conditions. My only problem is that it has no way (that I could find) to have a real time video feed on the computer.

Have you any ideas how to tackle this problem?

The Hero 3 has a real time output via it's micro HDMI socket which may be a good start. The GoPro may not be capable of driving too long an HDMI cable, but mine certainly does about 2 metres. After that, and/or you want good mobility, you may need some sort of HDMI to wireless link?

Alternatively you can get composite video out of the USB connector - HERO3 Composite Cable - since it's composite, it's likely to be SD, and whether PAL or NTSC and how it relates to the main camera settings, I don't know. (A bit fiddly with the menus, but you can switch off the on-screen display.)

(Bill - the Hero 3 doesn't have the 2.5mm socket - you can only get composite via the USB connector. Since the HDMI is high def, I'd be inclined to go for that as first choice.)

[Jason Jackson]

Thanks for the replies guys

I'm aware that these devices have a video out but my whole problem is how I get that video feed onto the computer.

I need a way to view the video feed on the computer that adds little to no latency. (not for the purposes of just seeing the video... i need a selectable video source so I can grab the video stream and use that data).

Would a video capture card be the best answer? Do they allow a live view of the video feed?

[David Heath]

Originally Posted by Jason Jackson

Would a video capture card be the best answer? Do they allow a live view of the video feed?

You can get the HDMI GoPro output into a laptop (via USB) with something like an Intensity Shuttle - Blackmagic Design: Intensity Models

As far as live view is concerned, that will depend on whatever software you use in the laptop for capturing, and it's pointless for us to speculate on that. Only you can decide what is best for your purposes and you have access to. There will inevitably be some latency, but I wouldn't expect it to be very much.

[Bill Davis]

Originally Posted by Jason Jackson

Thanks for the replies guys

I'm aware that these devices have a video out but my whole problem is how I get that video feed onto the computer.

I need a way to view the video feed on the computer that adds little to no latency. (not for the purposes of just seeing the video... i need a selectable video source so I can grab the video stream and use that data).

Would a video capture card be the best answer? Do they allow a live view of the video feed?

Also the simple Black Magic Video Recorder dongle will take any composite signal and run it into a computer USB port for H-264 encoding and capture in real time. I keep one in a drawer next to my edit bay just in case someone comes in with some older footage - you can feed it with anything from a VHS machine to a 3'/4 sp via composite. It works great. Fast and easy transcoding and capture.

[Jason Jackson]

this information is incredibly helpful, thanks a bunch guys

[David Heath]

Originally Posted by Bill Davis

.......... will take any composite signal and run it into a computer USB port for H-264 encoding and capture in real time.

What you say is true enough, but for the purposes of this experiment I'd tend to think a true progressive signal is likely to be more friendly than a composite (hence interlaced) to the computer for the purposes of the experiment?

Which is why I'd try and go with the HDMI output if at all possible........