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Grayscal conversion + min max bitonal treshold

hallo, i am sorry if i ask too simple questions as i am new to vvvv. i spent few days but i can´t find out.

i am trying to build multichannel multiblob tracking - based on the tracking of the different shades of gray. for this i need to “prepare” video for the contour nodes.

i think first i need to convert incoming video signal into grayscale. after making treshold with min max option which will filter needed segment of the gray scale. this should go to contour.

however i can´t find how to make this operation. i have previously programmed this system in eyesweb but the freeframe motion tracking plugin for vvv seems much better. especially it can very effectivelly keep track of the object (doesn´t swap id numbers).

i will be very thankfull for the help (some hint on the chain of the objects i should check).

all the best

tomas

hi tomas,

i would look for a freeframe node to process your video before the tracking node.
freeframe downloads

thank you for your suggestions. i checked it. unfortunatelly i can´t find such freeframe plugin as most of the ff plugins are primary focusing on effect aspect (vj stuff etc.). here i need some more video manipulation stuff: grayscale + kind of band pass filter (min max threshold) / do you have some particular plugins in mind which you think could be helpfull?

tomas

no, not really… do you have some programming skills? its easy to make your own freeframe plugin with dev-cpp and a code template that you can find here:
writing freeframe

hello dvorak,

you know the node AsVideo?
you could do the grayscale thing with a pixelshader … should be very easy and then use this node to put the data to the freeframe world.
the only problem is the performance.

did you look through all those plugins? http://freeframe.sourceforge.net/downloads.html

what about pete’s “levels” plugin? maybe you can do min/max thresholding with it.

vvvvs contour node itself only does a single value based threshold conversion to black and white of the input signal.

hallo,

joreg, are you the one who is actually the creator of the plugin?

thank you very much for your suggestions! i find hopefully efficient sollution.

i asked my brother who has programming skills and he added few lines to the source code. so now there is the min and max threshold and between them Xor logical operation is performed.

i will have to test it, i am not sure yet it works 100% correctly, but if so i hope it can be usefull for the others.

contour-min_max.zip (151.1 kB)
(0 Bytes)

ok sorry. there is small error in the “hacked contour” i put in the attachment in the previous post, it doesn´t seem the most black part of the grayscale spectrum. so please don´t download the file from the previous post.