Doom9's Forum - View Single Post - madVR - high quality video renderer (GPU assisted)

hannes69 · 6th October 2015, 00:32

@madshi and @all who are interested in automatic projector masking procedures

Question about the black bar topic:
I have a home cinema with a 16:9 projector and a 16:9 front projection (screen = white wall, surrounding painted black). For cinemascope movies or movies with an aspect ratio > 16:9 I use vertical adjustable black covered boards to mask the rest light of the DLP projector. I adjust them manually at the moment for every movie. I am an electric engineer and I like tinkering crazy stuff which doesn´t exist or one can buy for horror prices and can do it by yourself with less money... So winter is upcoming in Germany (=time for such projects) and I have a little idea: I want to automate the masking procedure. The used masking boards should easily be adjustable in height by using 4 DC motors (2 for top board, 2 for bottom board / each 2 controlled simultanousely) and threaded bars. By starting the system the boards run to a default position (= no masking), then I start a movie and then by pressing a button (eg remote controlled) the boards should run automatically to the desired position.
First thought for the solution was to go the simple way and use photodiodes to detect the edge between dark and bright and detect so the physical covered area of the movie. Maybe this would work with a good sensitivity of the photodiodes, bright areas of the movie on the top and bottom edges and a very dark room.
But in the meantime during I was thinking about the idea madshi came across with these nice settings with the black borders...
So the second solution would be more of a software based instead of the hardware based photodiode.
But that would require to gain the necessary information out of madvr. That would mean something like target rectangle out of an API. I can do a little bit of programming in C# (not very advanced, but I can do stuff like GUIs, automats,...) so no problem to implement the controlling of my masking setup eg by RS232 to get the information out of the PC. But I don´t know if A) I can get the necessary information out of madvr and B) if yes how.
If this is too complicated I would try the version with the photodiodes. The software based solution seems more reliable to me, so I would prefer this one

Greetings, Hannes.

6th October 2015, 00:32	#33397 \| Link
hannes69 Registered User Join Date: Nov 2012 Posts: 99	@madshi and @all who are interested in automatic projector masking procedures Question about the black bar topic: I have a home cinema with a 16:9 projector and a 16:9 front projection (screen = white wall, surrounding painted black). For cinemascope movies or movies with an aspect ratio > 16:9 I use vertical adjustable black covered boards to mask the rest light of the DLP projector. I adjust them manually at the moment for every movie. I am an electric engineer and I like tinkering crazy stuff which doesn´t exist or one can buy for horror prices and can do it by yourself with less money... So winter is upcoming in Germany (=time for such projects) and I have a little idea: I want to automate the masking procedure. The used masking boards should easily be adjustable in height by using 4 DC motors (2 for top board, 2 for bottom board / each 2 controlled simultanousely) and threaded bars. By starting the system the boards run to a default position (= no masking), then I start a movie and then by pressing a button (eg remote controlled) the boards should run automatically to the desired position. First thought for the solution was to go the simple way and use photodiodes to detect the edge between dark and bright and detect so the physical covered area of the movie. Maybe this would work with a good sensitivity of the photodiodes, bright areas of the movie on the top and bottom edges and a very dark room. But in the meantime during I was thinking about the idea madshi came across with these nice settings with the black borders... So the second solution would be more of a software based instead of the hardware based photodiode. But that would require to gain the necessary information out of madvr. That would mean something like target rectangle out of an API. I can do a little bit of programming in C# (not very advanced, but I can do stuff like GUIs, automats,...) so no problem to implement the controlling of my masking setup eg by RS232 to get the information out of the PC. But I don´t know if A) I can get the necessary information out of madvr and B) if yes how. If this is too complicated I would try the version with the photodiodes. The software based solution seems more reliable to me, so I would prefer this one Greetings, Hannes.