Hey Mathieu, Thanks for the tips much appreciated, I'm going to to work on something to extract sounds from video movements/colours basically. I've done this in Gem with pix_data & pdp with pdp_cog - trying out gridflow as I think there could be more ways of extracting values to explore
I dont think gridflow likes the mp4 suffix? the console displays [gf/io_generate 1012in] unknown suffix 'mp4' .Changing the suffix file manually from mp4 to .mov seems to resolve the issue though Thanks again On Wed, Aug 24, 2011 at 6:10 PM, Mathieu Bouchard <ma...@artengine.ca> wrote: > On Tue, 23 Aug 2011, ALAN BROOKER wrote: > >> I hope to ask for some tips regarding obtaining values from a loaded >> image/movie file by using gridflow ? #store gets can get rgb values >> from a specified pixel position > > You can pass multiple pixel positions at once to #store and it's much faster > than getting pixels one by one. Those multiple pixel positions can in turn > be organised in rows and columns so that you can make a new image by picking > 100000 pixels in a single step, for example. > >> but any advice on getting the whole dimensions at once > > What does that mean ? > >> (or any other techniques in getting gridflow to output values from a movie >> file such as movement, luminosity or anything)? > > some kind of luminosity is what you get when you convert to greyscale. You > may use [#rgb_to_greyscale]. > > Movement can be a lot of different things. > > The easiest one is to subtract each frame with the previous one. Then you > can know the change of luminosity from one image to the other, or the change > of each channel. You do that using [t a a] and [# -] (plain diff) or [# sq-] > (squared diff) or [# abs-] (absolute diff). > > You can also identify regions or compute mean positions of things and then > look at the position differences. Sometimes I did that using [#moment] and > then [t a a] and [# -]. Note that often the same tools work on different > kinds of data (pixel colours vs pixel positions). This is a feature of > GridFlow which is not found in other image-processors of Pd (GEM/PDP/etc). > > There are also algorithms to make a map of all translations (move) of pixels > in the picture, but they have not incorporated in GridFlow. > >> ...also is there support for mp4 in gridflow? the file format being the >> same as mov (I think?) > > GF uses Quicktime.framework (by Apple) on OSX, and libquicktime (by H.W. & > Plaum) on Linux and now also on OSX. Nearly all video file format support > rests upon that. > > GF also can run libmpeg3, but that's a MPEG1/MPEG2 decoder without plugins. > > _______________________________________________________________________ > | Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC > _______________________________________________ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list