livst / dense-flow

Dense Optical Flow extraction rewritten from https://github.com/wanglimin/dense_flow

dense-flow

Dense Optical Flow extraction rewritten from https://github.com/wanglimin/dense_flow

OpenCV 3.0

The tool has been rewritten to be compatible with OpenCV 3.0. Make sure you compile OpenCV with CUDA capabilities. If you installed OpenCV to a non-default path, please edit Makefile.config and edit the paths correspondingly.

Serialization

In case of long video files, generating thousands of jpegs may be inconvenient for copying. We added the possibility to serialize them into one file. If you DO NOT want to use this feature, please use 'make simple'.

Serialization requires boost library!

File format

All jpegs are encoded as a string (using OpenCV's imencode). The resulting vector of string is serialized using boost. unpacker.cc provides an example of how to extract the jpegs.

Chunks

After 20000 files, the serialized files are written to disk, and a new chunk is started. This can be changed by redefining MAX_FILES_PER_CHUNK in common.hh.

Compilation

To compile, create 'build' directory, and run 'make'.

Usage

Example: ./denseFlow_gpu --vidFile="video.mp4" --xFlowFile="flow_x" --yFlowFile="flow_y" --imgFile="im" --bound=16 --type=2 --device_id=0 --step=10

Reads from file video.mp4, saving the Dense Optical flow with corresponding prefixes flow_x / flow_y, the images with prefix im, cuts off all flow values < -16 and > 16, using method 2 (Brox Optical Flow) on GPU 0, sampling only every 10th frame.