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Rendertexture slows down unity?

I'm confused as to what is going wrong here but I am sure that the problem is my rendertextures/video players - I have maybe 20 gameobjects that are iPhones, and I need animated .mov files that I made to play behind the screens.
To do this I followed tutorials to hook up Videoplayers with render textures (now there are about 8 of them) like this, then plugging the render texture into the emission slot in a material:
And with even 2 render textured cubes the game is INCREDIBLY laggy, here are stats
I tried turning the depth off but don't know whats wrong here - my movie files are just in the KB range. How can I play videos without lagging?

Based on the CPU taking 848ms per frame rendered, you are clearly bottlenecked on CPU. If you want to run at 30 frames per second, you'll need to get CPU time below 33ms per frame.
Since the CPU time is getting markedly worse after adding video players, it seems that the video codec is taxing your CPU heavily. Consider reducing the video quality as much as possible, especially reducing the resolution.
If that won't work, you may need to implement a shader-based solution using animated sprite sheets. That's more work for you, but it will run much more efficiently in the engine.

Linear encoder with webcam to measure length

There are tools like digital caliper, linear encoders that measures lengths. the are basically rulers and they use magnetic strips. they simply count magnetic stripes and calculated the distance.
I want to make it optical by using webcam instead of using magnetic stripes.
Imagine a ruler with webcam pointed on it. dont think about numbers or anything. just imagine ruler with vertical lines. webcam placed to this ruler very closely and image is very clear.
as webcam moves, vertical lines will travel across video.
what I want to do is count these lines at the center of the video so I can calculate how far we go.
I googled every word I can think of to find a stating point I had no luck.
any suggestions please ? I need to use windows platform for this project. c# or vbnet are wellcome.
best...

Try this; it's not been updated in a while but the concepts are all there.
http://reprap.org/wiki/CamRap

C#: Capturing still images, from multiple (USB )cameras

I need some guidance.
I have to create a simple program, that captures still images every n Seconds, from 4 cameras, attached with USB.
My problem is, that the cameras cannot be "open" at the same time, as it will exceed the USB Bus bandwidth, so I will have to cycle between them.
How to do this, i'm not so sure about.
I've tried using EmguCV, which is a .NET wrapper for OpenCV, but I'm having trouble controlling the quality of my images. I can capture 1280x720, as intended, but it seems like they are just scaled up, and all the image files are around 200kb.
Any ideas on how to do this, properly?

I hate to answer my own question, but this is how I have ended up doing it.
I continued with EmguCV. The images are not very large (file size), but it seems like that is not an issue. They are saving with 96 dpi, and it looks pretty good.
I cycle through the attached cameras, by initiating the camera, taking a snapshot and then releasing the camera again.
It's not as fast as I had hoped, but it works. In average, there is 2 seconds between each image.

People Counting System

I want to develop a "People Counting System" using OpenCV (or Emgu CV).
Please guide me on how to implement or lead me to some examples or open source projects.
(I have done some work: extracting diff then threshold to delete background, using motion history and like that; still no good results.)
Edit 1: I am counting a high people flow (a dozen of them may come through simultaneously).
Edit 2: It must be at least 80% accurate. People are walking through a door that is almost 5 meters wide. The problem is I have no control on the position or angle of the camera. Camera is shouting the place from a 10m distance at a 2.5m height.
Thank you

If you call a people counting system a system that counts people that are in a room then I recommend you implement the hardware with a microcontroller with 2 lazers(normal lazer toys work) and 2 photoresistors.For the microcontroller I recomen you use Arduino.And then make an C# application that has a SerialPort object and reads the data that the arduino sends through the USB.The arduino will send 1 for "someone entered the room" and 0 for "someone left the room" for example.Then the logging and statistics can be done easily in C#.
Arduiono Site:here
Photoresistor for $1: here
This solution is alot cheaper and easyer to implement than using a camera that is with a fairly good quality.
Hope I helped you.

Check out the HOG pedestrian detector that comes with recent versions of OpenCV (>= 2.2).
See modules/objdetect/src/hog.cpp and samples/cpp/peopledetect.cpp in the OpenCV sources. Unfortunately there is no official documentation about it yet.

This would help you to count moving things including people: Motion Detection project on CodeProject

Are people the only kind of "entities" in the scene? If this is not the case, do you care about considering a person some other kind of thing that moves through the scene? Because if that is the case, you could just count blobs that come in or come out from the scene. It may sound a bit naive but I will take some kind of motion image, group motion pixels by distance in clusters. Your distance metric could take into account some restrictions, such as that people will "often" stand so pixels in a cluster should group around some kind of regression line (an straight-up line if the camera is aligned with de floor). It shouldn't be necessary to track them in the scene, just noticing when they enter or they leave, though you'd get some issues with, for example, people entering on their own in the scene and leaving in pairs or in groups... Good luck :)

I think if you have dense people crowd with a lot of occlusions you have to use some machine learning algorithm, for example you can use Implicit Shape Model for features.

It really depends on the position of the camera. Assuming that you can get front facing profiles of the people in the images:
This problem is basically face detection and recognition.
There are many ways to go about finding faces, but this is the approach that I'm a little more familiar with.
For the face detection you need to do image segmentation on the skin tone color. This will extract skin regions. [Arms, the chest (for those wearing V cut tops), face, legs, etc] Then you would need to line up the profiles of the skin regions to the profile of your trained faces.
[You'll need to use Eigenfaces to create a generic profile of what a face looks like]
If the skin region lines up and doesn't devate too far from the profile, then it is considered a face. Once the face is confirmed, then add it into the eigenfaces data store [for recognition]. To save processing you might want to consider limiting the search area if you are looking for a previous face. [Given the frame rate, and last time the person was seen]
If you are referring to "Crowd flow" I think you just mean the density of faces in a crowd.
Now you've confirmed that a moving object in the video is a person. Now you just need to note that and then make sure that you don't consider them as a new person again.
This approach: Really depends on your ability to detect face regions. This may not work if the people in the video are looking down, not fitting the profile of the trained data etc. Also it may be effected if a person puts on sunglasses within the video. [Probably would be considered a "new face"]

Capture a single pixel row from each frame of video and compile them together

I'm working on a project where I need to take a single horizontal or vertical pixel row (or column, I guess) from each frame of a supplied video file and create an image out of it, basically appending the pixel row onto the image throughout the video. The video file I plan to supply isn't a regular video, it's actually just a capture of a panning camera from a video game (Halo: Reach) looking straight down (or as far as the game will let me, which is -85.5°). I'll look down, pan the camera forward over the landscape very slowly, then take a single pixel row from each frame the captured video file (30fps) and compile the rows into an image that will effectively (hopefully) reconstruct the landscape into a single image.
I thought about doing this the quick and dirty way, using a AxWindowsMediaPlayer control and locking the form so that it couldn't be moved or resized, then just using a Graphics object to capture the screen, but that wouldn't be fast enough, there would be way too many problems, I need direct access to the frames.
I've heard about FFLib, and DirectShow.NET, I actually just installed the Windows SDK but haven't had a chance to mess with and of the DirectX stuff yet (I remember it being very confusing for me a while back when I messed with it). Hopefully someone can give me a pointer in the right direction.
If anyone has any information they think might help, I'd be super grateful for it. Thank you!

You could use a video rendered in renderless mode (E.g. VMR9, EVR), which allows you to process every frame yourself. By using frame stepping playback you can step one frame each time and process the frame.
DirectShow.NET can help you to use managed code where possible, and I can recommend it. It is however only a wrapper to DirectShow, so it might be worthwhile to look for more advanced libraries as well.
A few sidenotes: wouldn't you experience issues with lighting which differs from angle to angle? Perhaps it's easier to capture some screenshots and use existing stitching algorithms?