Improvements – Mirroring Piece

An improvement I received when testing my piece was to mirror the video capture. It came to my awareness that at the moment it captures the video the wrong way round, so when users put up their right hand, on the screen their hand goes up on the left. This makes the interaction quite confusing which could deter people from interacting with my piece. I have found this improvement quite difficult to do and have had quite a bit of difficulty with the programming. Through reading online forums, I managed to gain some help from others who had similar problems. Here are the steps I went through and the various problems I encountered:

Screen Shot 2015-01-13 at 12.58.02To start with I managed to get my piece to mirror by adding this code:
Screen Shot 2015-01-12 at 12.23.50

This got the video capture to mirror but meant the brightness thresholding wouldn’t work correctly and so the video capture was in colour. This meant that obstructing the falling objects didn’t work as well as it was harder to detect the threshold on colours. Also, I felt that the black and white capture looked better as the coloured shapes stand out more.

As I was having difficulty, I decided to start my piece from scratch as originally I had used the brightness thresholding example. I felt that starting from scratch would help me to solve the problems easier as I would be writing out all the code step by step, in a way that I understood. I managed to resolve the problem by adding in videoMirror and a for loop to go through each of the video pixels. Then, instead of using the normal formula of x+y*width to access the array of pixels, I set it equal to [(width-(x+1))+y*width].

Screen Shot 2015-01-13 at 10.28.16

This flipped the video capture and the brightness thresholding still worked correctly. However, this caused the an error with the falling shapes. Now, when you put up your right hand to obstruct the shapes, it obstructs them up the left hand side. This meant I had to flip the shapes too, which I managed to do by changing the x co-ordinate of the shapes to (width-1-x).

Screen Shot 2015-01-13 at 13.04.08

Carrying out user testing with my family and friends was very useful and now my piece is mirrored correctly. This shows that I have followed an iterative design process as I created my piece, got feedback and then made improvements. I have learnt a lot more by carrying out this improvement, especially in relation to the advantages and disadvantages of hacking/programming. I feel that now I have programmed from scratch, my knowledge and understanding has advanced and I’m more confident with resolving any further problems I may encounter.  Next, I will go on to explore some other suggested improvements, such as adding more of each shape and altering speeds. Then, I will go on to test my piece in the studio room, capturing full body movement using a white screen.

Processing Forum, 2014. Mirroring a Webcam in a Sketch. Processing [online]. Available from: [Accessed12 Jan].

Processing Forum, 2014. Flip the Video Capture on the X-axis.Processing [online]. Available from: [Accessed11 Jan].


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