darkflow in macOS

YOLO: Real-Time Object Detection 目標是想要可以在macOS上用camera跑demo(沒有nvidia GPU)，於是找到darkflow，記錄實作過程如下：

環境需求：Python3, tensorflow 1.0, numpy, opencv 3.

Python使用pyenv安裝，用3.6.x會失敗． virtualenv用pyenv virtualenv．

pyenv install 3.5.4
pyenv shell 3.5.4
pyenv virtualenv venv
pyenv activate venv

pip install Cython
pip install numpy
pip install opencv-python
pip install --upgrade tensorflow
pip list
>>
Cython (0.27.3)
numpy (1.13.3)
opencv-python (3.3.0.10)
tensorflow (1.4.0)

之後的安裝步驟照著darkflow readme，getting-started

git clone https://github.com/thtrieu/darkflow.git
cd darkflow
pip install -e .

flow --h
>>
Example usage: flow --imgdir sample_img/ --model cfg/yolo.cfg --load bin/yolo.weights

下載weights，從yolo

wget https://pjreddie.com/media/files/yolo.weights
mv yolo.weights bin/.

可以開始使用，輸出的video會放在同個目錄下。

flow --model cfg/yolo.cfg --load bin/yolo.weights --demo camera --saveVideo