Optical flow extraction tool using OpenCV. The code is simple and mostly from documentation of OpenCV, but it makes it easy to use for pre-processing of videos with several options. It is easy to customize and change the algorithms used. Currently Brox algorithm is used for GPU and Farneback is used for CPU implementations.
TO-DO
Type ./flow_video -h to see the help message below.
USAGE:
[-h] [-p <proc_type>] [-o <out_dir>] [-b <interval_beg>] [-e <interval_end>] [-v <visualize>] [-m <output_mm>] <input_name>
INPUT:
<input_name> : Path to video file or image directory (e.g. img_%04d.jpg)
OPTIONS:
-h : Display this help message
-p <proc_type> [gpu] : Processor type (gpu or cpu)
-o <out_dir> [./] : Output folder containing flow images and minmax.txt
-b <interval_beg> [1] : Frame index to start (one-based indexing)
-e <interval_end> [last] : Frame index to stop
-v <visualize> [0] : Boolean for visualization of the optical flow
-m <output_mm> [<out_dir>/<basename(input_name)>_minmax.txt] : Name of the minmax file.
Notes:
*GPU method: Brox, CPU method: Farneback.
*Only <imagename>_%0xd.jpg (x any digit) is supported for image sequence input.Extract flow from the frame interval 5-10.
./flow_video -b 5 -e 10 -o samples/out samples/video/video.avi
./flow_video -b 5 -e 10 -o samples/out samples/images/img1/img1_%05d.jpg