>> Stefan, can you provide some sample IR footage with the IR in the red >> and VIS in the blue channel like you described above? > > Yup, in 2 or 3 weeks. I'm waiting for the filter sheet and some lenses > to arrive.
That's a long time to wait. What about one of the 54000 DIY-Drones members? Does anyone have any footage they could share? I put together a proof of concept using frei0r: https://github.com/pez4brian/frei0r/commit/7c0704a1d5f4a418b17f6f2ead11067e7a0680f7 Since I don't have any example video files, I used an example image I found here: http://infrapix.pvos.org/ The melt command is: melt river.jpg -attach frei0r.ndvi The output is a grayscale image with NDVI mapped to values between 0 and 255. I can add the frei0r heat filter and get colors that are very similar to the image generated by the infrapix site. The melt command to include the heat map is: melt river.jpg -attach frei0r.ndvi -attach frei0r.colortap 0=heat I think that we will eventually want the false color mapping to be done in the ndvi filter (rather than being applied by a downstream filter) because the output grayscale image will only have 256 possible values that can be mapped to colors. But there are 65536 (256x256) possible NDVI values. So some resolution will be lost when mapping from grayscale. Also, if you search around, I see different color mappings being used... Earth tones: http://earthobservatory.nasa.gov/Features/MeasuringVegetation/Images/global_ndvi_19990921.jpg Green represents vegetation: http://en.wikipedia.org/wiki/File:NDVI_062003.png Red represents vegetation: http://i.publiclab.org/system/images/photos/000/002/682/original/IMG_0093a_NDVI_Color_2Cam.jpg There is a free app out there called Fiji that processes infrablue images: http://event38.wikispaces.com/NDVI+Processing+in+Fiji It includes a host of configuration options including the ability to scale the NIR channel and configure a custom color mapping. It would be worth considering if any of those configuration options should be added to the filter. ~BM ------------------------------------------------------------------------------ HPCC Systems Open Source Big Data Platform from LexisNexis Risk Solutions Find What Matters Most in Your Big Data with HPCC Systems Open Source. Fast. Scalable. Simple. Ideal for Dirty Data. Leverages Graph Analysis for Fast Processing & Easy Data Exploration http://p.sf.net/sfu/hpccsystems _______________________________________________ Mlt-devel mailing list Mlt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mlt-devel
