Connecting a camera to a flat screen without software

Thread Starter

4everJang

Joined Jul 21, 2023
13
Hoping to get some pointers from more experienced people on this forum.

One of my art projects is The Hole Body - a jacket with flat screens plus cameras on front and back, with the front camera connected to the back flat screen and vice versa. This means people can look through me when I am wearing the jacket and switch it on. If possible, I do not want to use any software for this.
I have looked at camera surveillance systems but they tend to have very small screens, use WiFi or other connectivity and software to allow all kinds of things I do not need. I simply want to have the image of the color cameras passed to the flat screens without any delays. I have tested a USB camera on a tablet but the tablet OS is making things so slow that the image is hardly recognisable when moving the camera. Also it is expensive to get large tablets with everything included and then only use it to show a live image.

If you have ideas about cameras and flat screen hardware to use for this, let me know. Thanks in advance.
 

Ya’akov

Joined Jan 27, 2019
9,165
Welcome to AAC.

What you are asking seems simple, but doing it cheaply is complicated. It would be very easy if money was no object because there are cameras for industrial and scientific applications that could be easily applied—but those are extremely expensive.

There is an additional problem of lenses. The focal length will be critical to get a good effect but varifocal (zoom) lenses are expensive and bulky. Lower profile lenses may or may not be appropriate—you will have to experiment to decide what focal length gets you what you want.

The easiest route for you will be to get a camera (system) that outputs HDMI, and a monitor that can accept it. The easiest way to do this isn’t without software, but the reason you’ve specified that may not apply. Here’s the rundown:

The is a version of the Raspberry Pi SBC (Single Board Computer) called the Raspberry Pi Zero. It is a very small, very cheap computer that runs the Linux operating system and has to important connectors: an OV5647 ribbon cable connector for a camera and an HDMI connector for a display.

1705316794352.png
RPi Zero


There are many compatible camera modules with various lenses—the figure below has a 72° FoV autofocus lens and a 5MP sensor. It is basically the same camera you’d find as a laptop webcam. There are many others with larger lenses (better, but bulkier).
1705316268925.png
OV5647 camera module
You will have to install a compatible version of Linux (Raspberry Pi OS, DietPi (my preference), etc.) and a small program that showed the camera full screen, and connect the RPi Zero to an HDMI display (I don’t have any immediate device on which one of these, it will depend heavily on your æsthetic choice) using a cable from its micro HDMI connector.

This will work and should have minimal lag. Any solution that allows for direct connection from camera to display will suffer the same problems: unwieldy size and/or unacceptable cost.
 

BobTPH

Joined Jun 5, 2013
8,967
I hope you realize that it can only look like a hole from one exact angle to one eye. I suspect that you will be very disappointed in the result even if it works.
 

MisterBill2

Joined Jan 23, 2018
18,517
There is an additional scheme that will allow viewing camera images on computer screens, and those are called "scan converters." They are not cheap either.
There are also small cameras with video outputs in other formats, such as composite video that only requires a single coaxial cable. And there may even be available flat screen monitors that would display that composit video directly. But probably none of it at the local computer store.
So the point is that, presuming you have not already purchased incompatible devices, that simply getting both camera and monitor that use the same format is the easy way to go.
There are also cameras with an HDMI (DVI) output (not cheap) that would connect to a monitor with an HDMI input. So the big deal will certainly be getting all of the pieces that "speak the same language."
 

Ya’akov

Joined Jan 27, 2019
9,165
Old Nikon cameras have an RCA output. Dash cams and backup cameras have RCA output.
No software needed.
Old Nikon camera are too large for the application
Backup cameras use very wide angle lenses that are probably not going to have the desired effect

RCA outputs (composite video) requires a monitor that can handle it. Currently available monitors will be small, older ones will be very thick and heavy.
 

Thread Starter

4everJang

Joined Jul 21, 2023
13
I hope you realize that it can only look like a hole from one exact angle to one eye. I suspect that you will be very disappointed in the result even if it works.
Good point. I will take that into consideration when deciding on making this project into reality or not. If the costs (money and time) are not too much it would be nice to make it work, even if it is only working for someone who is straight ahead or straight in front and has average body height.
 

MisterBill2

Joined Jan 23, 2018
18,517
My big point was not to discourage the concept or the project, but rather to point out the solutions. As for cameras, security product companies have listed small cameras for hidden applications for many years. They also offered assorted monitors in a variety of sizes. So a contact with one of those companies may provide good information about what is available.
 

ApacheKid

Joined Jan 12, 2015
1,610
Hoping to get some pointers from more experienced people on this forum.

One of my art projects is The Hole Body - a jacket with flat screens plus cameras on front and back, with the front camera connected to the back flat screen and vice versa. This means people can look through me when I am wearing the jacket and switch it on. If possible, I do not want to use any software for this.
I have looked at camera surveillance systems but they tend to have very small screens, use WiFi or other connectivity and software to allow all kinds of things I do not need. I simply want to have the image of the color cameras passed to the flat screens without any delays. I have tested a USB camera on a tablet but the tablet OS is making things so slow that the image is hardly recognisable when moving the camera. Also it is expensive to get large tablets with everything included and then only use it to show a live image.

If you have ideas about cameras and flat screen hardware to use for this, let me know. Thanks in advance.
 

WBahn

Joined Mar 31, 2012
30,062
Hoping to get some pointers from more experienced people on this forum.

One of my art projects is The Hole Body - a jacket with flat screens plus cameras on front and back, with the front camera connected to the back flat screen and vice versa. This means people can look through me when I am wearing the jacket and switch it on. If possible, I do not want to use any software for this.
I have looked at camera surveillance systems but they tend to have very small screens, use WiFi or other connectivity and software to allow all kinds of things I do not need. I simply want to have the image of the color cameras passed to the flat screens without any delays. I have tested a USB camera on a tablet but the tablet OS is making things so slow that the image is hardly recognisable when moving the camera. Also it is expensive to get large tablets with everything included and then only use it to show a live image.

If you have ideas about cameras and flat screen hardware to use for this, let me know. Thanks in advance.
What you are trying has been the method used by sci-fi invisibility cloaks for decades -- and it has a very fundamental flaw (which sci-fi conveniently ignores).

Imagine trying to do something like create a mirror using the same approach -- mount a camera in the middle of a display and simply display the image it sees on the screen (reversed if necessary).

But that means that everyone sees the same image in the mirror, regardless of where they are standing. That's not how mirrors behave. You need a display that lets you project different images at different angles -- and such displays do exist, though their capabilities are pretty rudimentary and they are extremely expensive (I don't know if any are even in actual commercial production).

You need the same kind of behavior for you jacket since every person looking at you has to see what is on the opposite side of you from THEIR perspective.
 

ApacheKid

Joined Jan 12, 2015
1,610
What you are trying has been the method used by sci-fi invisibility cloaks for decades -- and it has a very fundamental flaw (which sci-fi conveniently ignores).

Imagine trying to do something like create a mirror using the same approach -- mount a camera in the middle of a display and simply display the image it sees on the screen (reversed if necessary).

But that means that everyone sees the same image in the mirror, regardless of where they are standing. That's not how mirrors behave. You need a display that lets you project different images at different angles -- and such displays do exist, though their capabilities are pretty rudimentary and they are extremely expensive (I don't know if any are even in actual commercial production).

You need the same kind of behavior for you jacket since every person looking at you has to see what is on the opposite side of you from THEIR perspective.
I once wondered about 3D TV, we had one but hardly used the 3D feature. But in principle one could have two different movies on at once and each viewer could see only their move, with headphones the sound could be split too.

Imagine being able to watch Gladiator while your wife watches Love Actually on the same TV!
 

MisterBill2

Joined Jan 23, 2018
18,517
What I see is a porential show stopper, which is being sure that the camera video is in a format that the monitor will display.. IF you can find a camera with an HDMI output then getting a monitor with an HDMI input should work. BUT look at the list! the one ad even states that the output can be in an "RCA" format. Say WHAT!!! that might be NTSC composite video, or it might be PAL composite video
 
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