Invisible Cloak using OpenCV

-
Have you ever seen Harry Potter’s  Invisible Cloak  If not then let's have a look.

 
 
Was it wonderful? Do you surprised how this can be possible? If yes, then this post is going to help you. You will be able to make such invisible cloak by your own but yes, not in real way but it is all about graphics.

Algorithm behind the idea

  • First, we take the background frame ( for some second ) and store in the memory.
  • Then, we will take the frame with cloth.
  • Then, detect and segment the portion of the cloth of pre-determined color. For Example here we will use Red. [ known as Color Detection and Image Segmentation ]
  • Then, that segment will be replaced by the background, we have stored in the memory, segment.
  • At last, create the final image to make the magic.

Note: All the things will be done in python due to the availability of the various libraries mainly numpy.

Python Code:

  • First of all, importing all the required libraries.
python code
 
  • To make a video of the output screen, we are required the first two lines of code. Then we take the background image( for some second )and filp it and save as image. 
python code
 
  • All the code, from this,  will execute till the output window is opened. Here first we take the frame with the red cloth, flip it and save as image. Then we have to transform the image into HSV  format( another method of image reading like RGB ). And save that transformed image also.
python code

  • Then we create one mask using two mask one with lower value (0 to 10) of Red color in HSV format and the other one with higher value (170 to 180) of Red color in HSV format.
HSV color model

python code

  • The mask may contain some noise. For that, removal of noise using morphological transformation and dilation, to be done on the image. And after that we make mask2 ( purpose of this can be understood later ) using mask1 by using cv2.bitwise_not (). Then we save the mask2 image also.
python code

  • Then we are applying mask1 on the background and mask2 on the image using cv2.biwise_and() and each time we save the images to see what happed in each step. This will continue till we press the 'ESC' key [ Ascii value is 27 ]
python code

  • At the end release the output window and destroy the window.
python code

Output of the python code

python code output image
python code output imagepython code output imagepython code output imagepython code output imagepython code output image
python code output image
python code output imagepython code output image


The video that was recorded

          

Conclusion

From this post we have learnt how to make the invisible cloak  using open-cv and numpy in python.


Comments

Post a Comment

Popular posts from this blog

Introduction to Computer Vision

-
Image
  Do you ever think, how Facebook can automatically tag your friend when you upload an image, how your smart phone can recognize you, using it's very advanced and accurate  Face recognition feature.  Have you ever thought how a picture is processed by computer , how a picture  is stored in computer  etc.   These are very few examples, many more will be discussed as we go on, of Computer Vision. Well, In this post we are going to discuss about Computer Vision. So let's get started. What is C omputer Vision ? Computer Vision is a  interdisciplinary field that helps computer to make high-level understanding from digital images and videos to automate the task that human visuals do. It use some techniques  by which computer can understand many useful information from an image and perform some action based on that information. We see an image and our brain can understand the message, delivered by the image. Machines do exactly the same thing. ...
Read more

Distance measurement using opencv

-
Image
In Covid-19 pandemic, we all know about the importance of Social Distancing . Right now, It is the only thing that can help to reduce the number of affected people. So I have decided to make a social distancing checker using python. The main idea is to measure the distance of object in the image and if the distance between two objects are less than some predefined pixel value then 'green' dot at the center of the bounding-box will convert to 'red' dot . The output of the code will like this- social distancing checker Python code for Distance Measurement I am providing the python code to measure the distance of the object in the image or each frame of a video. Later I will discuss some key points related to the code. Key points to be Noted: Everything will be the same like object detection (discussed in Part-I and Part-II ) as I have implemented distance measurement based on object detection. We will filter out only the  'person' object   from the obje...
Read more

Object Detection (PART-II)

-
Image
  The  most fundamental computer technology  related to Computer vision and Image Processing is  Object Detection.  It deals with detecting the   semantic object of a certain class in digital images and videos. In the previous post, I have shown you how to detect object very easily with less than 15 lines of code. But our concern is about the FPS(Frames Per Second). Check out the  Object Detection (PART-I)    if you have not seen yet.  In this post, we are going to optimize the previous post so that we can improve the FPS. In this case also we are gong to use YOLO  model again. There are 80 different classes that can be detected using YOLO model. such as-       person, bicycle, car, motorcycle, airplane, bus, train, truck, boat, traffic light, fire hydrant, stop_sign, parking meter, bench, bird, cat, dog, horse, sheep, cow, elephant, bear, zebra, giraffe, b...
Read more