Using the Raspberry Pi Camera to see through the mirror

Synthic

So I just completed my magic mirror build where I attempted to integrate the rpi camera
I mounted it on the back and drilled a hole for it to see through. However the video feed is almost completely black, and I am not able to make out anything from the footage (it’s that bad). The camera works fine when not placed behind the mirror. I placing my phone in place of the rpi camera and it takes images just fine.

Does anyone have any experience with this? I’m confused as to why the rpi camera fails to see through the dark side of the mirror, while my phone camera can do it no problem?

Thanks!

johnnyboy

@Synthic

Theres another post here somewhere regarding this, and I’m sure it states that the camera wont work through the mirror? also that someone else used the Noir version, and had ‘‘OK’’ results.

One should never try and compare a phone camera, to the Rpi camera… they are worlds apart! ;-)

Synthic

Thanks, I think I found the post you mentioned. I should have done better research first…:/ I was just so disappointed with how poorly it worked xD

I know the rpi camera and a phone camera are two completely different things (even though my mobile’s camera is shit) I was just very surprised by how vast the difference was.

Guess I have to procure a NoIR camera then ^^

johnnyboy

@Synthic

If its possible, you could incorporate the PiCamera into your frame? As a few others have. As the Noir is a Night Vision Camera, so may not be up to your expectations?

Others have even used webcams, that also incorporate the built in microphone, thus doubling up its capabilities and negates the need to purchase a seperate microphone.

If you are happy enough with the quality of the pictures from your PiCamera outside of the mirror, then I would suggest just keeping that one and come up with some design to place it discreetly into the frame, or placed on top, or bottom ? As i’m unsure even I would be happy with the Noir night vision camera as being a normal picture taking camera.

dpenney

@Synthic We as using the picam behind the mirror without any issues. If you place it right behind the glass do you see the same thing or only when it’s in the hole you drilled?

Synthic

@johnnyboy The thing is that my design is a frameless mirror - hence why I wanted the camera to be able to see through the mirror. But a webcamera that incorporates the microphone was a really good idea as I also intend to some voice command recognition.

I only want the camera for doing facial recognition, so as long as the noir camera is able to get high enough quality for facial features to be distinguished - that will be good enough for me.

Thanks!

Synthic

@dpenney Whether the PiCamera is directly behind the mirror, or looking through the mirror through the drilled hole does not matter. The images taken are equally bad

Synthic

@johnnyboy Do you have any familiarity with webcams with built-in microphone that are small and compact? As to not make the mirror thicker than needs be.

slametps

I’m using the exact rpi camera, and it’s working flawlessly with facial-recognition module. also taking a picture or record video. Have you test the camera before attached to its place?

johnnyboy

@Synthic

There are quite a lot of webcams out there with built in microphones… So best Google or have a look at styles/shapes/sizes on Amazon or Fleabay to get an idea of what suits. Im sure they are all more-or-less same megapixels? apart for the higher end ones that also record in HD, and has twin microphones… also ones with Facial recognition like the M$ Hello Face recognition which I think is windows 10 only??? so all depends on your budget, and what you want from it, also the size and casing incase you can/want to strip it down for a better fit?

lolobyte

Hi @Synthic,

i use since 2 weeks the mirror glass ordered at @Goldjunge_Chriz ad the result is fantastic. With my mirror before the video was very darken. i send you asap a picture of my videoframe.

Synthic

@slametps Yeah, I know the camera works well normally. So your camera works by seeing through the mirror from the other side? Did you have to tweak any camera settings or did it just work?

lolobyte

@Synthic yes behind the mirror glass without any tweaks.

broberg

Do consider that there is difference in properties between the types of two way mirrors out there,
one type could work well with a camera lens while another type doesn’t work at all.

for an example many two way coatings are made to filter out IR light.

Synthic

@broberg That is a valid point. How would one know what kind of two-way mirror I posess? Haven’t been able to find any “comprehensive overview” of two-way mirrors

dpenney

@Synthic Infrared is blocked by cameras anyway so that wouldn’t make a difference. The only thing the camera cares about is visible light so if you are able to see through the mirror you are using then there is no reason that the camera shouldn’t be able to do the same thing regardless of what material the mirror is made from.

I too have the basic PiCam located behind the glass and it works perfectly. Does your cam work without the glass in place?

Synthic

@dpenney That’s what bugs me:

The PiCamera works great normally
I can see through the mirror
My Nexus 5 camera can see through the mirror
The PiCamera can not. (it CAN, but it is waaaay too dark)

dpenney

@Synthic That is frustrating…

I think the facial recognition module uses python-picamera to talk to the camera, are you able to tweak the configs somewhere in order to up the brightness?
https://www.raspberrypi.org/documentation/usage/camera/python/README.md

dpenney

This is where the camera is setup - try adding
camera.brightness = 90

https://github.com/paviro/MMM-Facial-Recognition/blob/master/facerecognition/picam.py

Worth a shot :)

broberg

@Synthic I can tell you that my nexus 5 camera does not like my glass at all, al tough, the light transmission on my mirror is really low.