looking at binning in ffld
aha, my 'ori' stuff from atan2_table is also quantized into the range of 0 to 18
inspecting how pixels go to HOG bins
padx, pady
wow, for an example HOG cell in ffld -- (y=6, x=16) -- there are 480 pixels that contribute. this is with sbin=4.
ah, that 480 number was high, because it was including several scales
just doing top pyra level
interesting. JUST doing the top pyra level, with no openmp, takes 50ms in FFLD. (for reference, we can pretty much do all the levels in 50ms with openmp)
yeah, 48 pixels contribute to hog cell (y=6, x=16) when we're doing just 1 level with sbin=4.
ooh, y=6 was near the edge. If we do an arbitrary location toward the middle of the HOG, then 64 pixels contribute to each bin, when we're computing HOG CELLS.
working on details of hog cells
working out hog cell indexing
precomputing first few rows/cols of gradients ... debating whether this is actually a good idea
decided that precomputing gradients is probably just unnecessary code complexity ... going to just have some branching/ternaries in the main loops to check whether enough data is ready to compute hog cells
cells