Head-camera face detection analyses
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README.md

xsface

Head-camera face detection analyses

Notes on framerate

Getting the framerate right across different methods is challenging. For example, in video 0401, it registers at 4:49 = 289 s, with quicktime 7 fps = 22.7 fps. 22.7 * 289 = 6560 frames, and quicktime 7 outputs 6437 frames. This framerate variability is due to dropped frames.

But: ffmpeg with general options outputs 8961 frames (30 * 289 = 8670). That's because ffmpeg is trying to get out 30 fps. ffmpeg with "-vsync 0" does the right thing, mostly, though, except in the case of 1610 and 1612, where we need "vsync 2" - but we have to be careful (1612 doesn't work at all at a certain point):

ffmpeg -i input.mp4 -vf "hflip,vflip,scale=720:480" -vsync 0 input/image-%5d.jpg