import?os
from?timeit?import?time
import?sys
import?cv2
import?numpy?as?np
from?PIL?import?Image
from?yolo?import?YOLO

from?application_util?import?preprocessing
from?deep_sort?import?nn_matching
from?deep_sort.detection?import?Detection
from?deep_sort.tracker?import?Tracker
from?tools?import?generate_detections?as?gdet
from?deep_sort.detection?import?Detection?as?ddet

‘‘‘
This?project?does?both?detection?and?tracking?of?objects.
It?utilizes?the?following?project.
Tracker?is?based?on:?https://github.com/nwojke/deep_sort
Detector?is?based?on:?https://github.com/qqwweee/keras-yolo3
Just?call?detect_video?to?start?the?program.
Or?just?run?py?py?app.py?to?see?a?demo.
Also?you?can?refer?to?the?usage?example?below.
@Params
yolo:?Yolo?detector?object.
filename:?filename?of?video?to?be?detected
path:?path?of?video?to?be?detected
resize_flag:?whether?the?video?to?be?processed?should?be?rescaled?by?half.
‘‘‘


def?detect_video（yolo?filename=‘‘?path=‘‘?resize_flag=False）:
????#?define?video?path
????fullpath?=?path?+?filename

????model_path?=?yolo.model_path
????model_name?=?model_path.split（‘/‘）[1][:-3]
????output_path?=?‘‘
????if?resize_flag?==?True:
????????output_path?=?f‘output/resized-{model_name}‘
????else:
????????output_path?=?f‘output/original-{model_name}‘
????#?create?output?dir?if?not?exist
????if?not?os.path.exists（output_path）:
????????os.makedirs（output_path）
????#?Gating?threshold?for?cosine?distance
????max_cosine_distance?=?0.2
????#?Maximum?size?of?the?appearance?descriptors
????nn_budget?=?None
????#?Non-maxima?suppression?threshold
????nms_max_overlap?=?1.0

????#?deep_sort
????model_filename?=?‘model_data/mars-small128.pb‘
????encoder?=?gdet.create_box_encoder（model_filename?batch_size=1）

????metric?=?nn_matching.NearestNeighborDistanceMetric（
????????“cosine“?max_cosine_distance?nn_budget）
????tracker?=?Tracker（metric）

????writeVideo_flag?=?True

????video_capture?=?cv2.VideoCapture（fullpath）
????if?writeVideo_flag:
????????#?Define?the?codec?and?create?VideoWriter?object
????????w?=?int（video_capture.get（3））
????????h?=?int（video_capture.get（4））
????????if?resize_flag?==?True:
????????????#?default?to?resize?by?half
????????????w?=?int（w/2）
????????????h?=?int（h/2）
????????fourcc?=?cv2.VideoWriter_fourcc（*?‘MJPG‘）
????????#?trim?the?filename?to?get?rid?of?file?extension
????????filename?=?filename[:-4]
????????#?result?output
????????out?=?cv2.VideoWriter（
????????????f‘{output_path}/output-{filename}.avi‘?fourcc?15?（w?h））
????????#?location?of?detected?objects
????????list_file?=?open（f‘{output_path}/detection-{filename}.txt‘?‘w‘）
????????#?framerate?of?detection.
????????fps_file?=?open（f‘{output_path}/framerate-{filename}.txt‘?‘w‘）
????????frame_index?=?-1

????fps?=?0.0

????while?True:
????????ret?frame?=?video_capture.read（）??#?frame?shape?640*480*3
????????if?ret?!=?True:
????????????break
????????h?w?_?=?frame.shape
????????if?resize_flag?==?True:
????????????frame?=?cv2.resize（frame?（int（w/2）?int（h/2））