<gh_stars>0
from ctypes import * 
import math
import random
import os

altNames = None

def sample(probs):
    s = sum(probs)
    probs = [a/s for a in probs]
    r = random.uniform(0, 1)
    for i in range(len(probs)):
        r = r - probs[i]
        if r <= 0:
            return i
    return len(probs)-1

def c_array(ctype, values):
    arr = (ctype*len(values))()
    arr[:] = values
    return arr

class BOX(Structure):
    _fields_ = [("x", c_float),
                ("y", c_float),
                ("w", c_float),
                ("h", c_float)]

class DETECTION(Structure):
    _fields_ = [("bbox", BOX),
                ("classes", c_int),
                ("prob", POINTER(c_float)),
                ("mask", POINTER(c_float)),
                ("objectness", c_float),
                ("sort_class", c_int)]


class IMAGE(Structure):
    _fields_ = [("w", c_int),
                ("h", c_int),
                ("c", c_int),
                ("data", POINTER(c_float))]

class METADATA(Structure):
    _fields_ = [("classes", c_int),
                ("names", POINTER(c_char_p))]


hasGPU = True
lib = CDLL('net/libdarknet.so', RTLD_GLOBAL)

lib.network_width.argtypes = [c_void_p]
lib.network_width.restype = c_int
lib.network_height.argtypes = [c_void_p]
lib.network_height.restype = c_int

copy_image_from_bytes = lib.copy_image_from_bytes
copy_image_from_bytes.argtypes = [IMAGE,c_char_p]

def network_width(net):
    return lib.network_width(net)

def network_height(net):
    return lib.network_height(net)

predict = lib.network_predict_ptr
predict.argtypes = [c_void_p, POINTER(c_float)]
predict.restype = POINTER(c_float)

if hasGPU:
    set_gpu = lib.cuda_set_device
    set_gpu.argtypes = [c_int]

make_image = lib.make_image
make_image.argtypes = [c_int, c_int, c_int]
make_image.restype = IMAGE

get_network_boxes = lib.get_network_boxes
get_network_boxes.argtypes = [c_void_p, c_int, c_int, c_float, c_float, POINTER(c_int), c_int, POINTER(c_int), c_int]
get_network_boxes.restype = POINTER(DETECTION)

make_network_boxes = lib.make_network_boxes
make_network_boxes.argtypes = [c_void_p]
make_network_boxes.restype = POINTER(DETECTION)

free_detections = lib.free_detections
free_detections.argtypes = [POINTER(DETECTION), c_int]

free_ptrs = lib.free_ptrs
free_ptrs.argtypes = [POINTER(c_void_p), c_int]

network_predict = lib.network_predict_ptr
network_predict.argtypes = [c_void_p, POINTER(c_float)]

reset_rnn = lib.reset_rnn
reset_rnn.argtypes = [c_void_p]

load_net = lib.load_network
load_net.argtypes = [c_char_p, c_char_p, c_int]
load_net.restype = c_void_p

load_net_custom = lib.load_network_custom
load_net_custom.argtypes = [c_char_p, c_char_p, c_int, c_int]
load_net_custom.restype = c_void_p

do_nms_obj = lib.do_nms_obj
do_nms_obj.argtypes = [POINTER(DETECTION), c_int, c_int, c_float]

do_nms_sort = lib.do_nms_sort
do_nms_sort.argtypes = [POINTER(DETECTION), c_int, c_int, c_float]

free_image = lib.free_image
free_image.argtypes = [IMAGE]

letterbox_image = lib.letterbox_image
letterbox_image.argtypes = [IMAGE, c_int, c_int]
letterbox_image.restype = IMAGE

load_meta = lib.get_metadata
lib.get_metadata.argtypes = [c_char_p]
lib.get_metadata.restype = METADATA

load_image = lib.load_image_color
load_image.argtypes = [c_char_p, c_int, c_int]
load_image.restype = IMAGE

rgbgr_image = lib.rgbgr_image
rgbgr_image.argtypes = [IMAGE]

predict_image = lib.network_predict_image
predict_image.argtypes = [c_void_p, IMAGE]
predict_image.restype = POINTER(c_float)


def array_to_image(arr):
    import numpy as np
    arr = arr.transpose(2,0,1)
    c = arr.shape[0]
    h = arr.shape[1]
    w = arr.shape[2]
    arr = np.ascontiguousarray(arr.flat, dtype=np.float32) / 255.0
    data = arr.ctypes.data_as(POINTER(c_float))
    im = IMAGE(w,h,c,data)
    return im, arr

def classify(net, meta, im):
    out = predict_image(net, im)
    res = []
    for i in range(meta.classes):
        if altNames is None:
            nameTag = meta.names[i]
        else:
            nameTag = altNames[i]
        res.append((nameTag, out[i]))
    res = sorted(res, key=lambda x: -x[1])
    return res

def detect(net, meta, image, thresh=.5, hier_thresh=.5, nms=.45, debug= False):
    im = load_image(image, 0, 0)
    if debug: print("Loaded image")
    ret = detect_image(net, meta, im, thresh, hier_thresh, nms, debug)
    free_image(im)
    if debug: print("freed image")
    return ret

def detect_image(net, meta, im, thresh=.5, hier_thresh=.5, nms=.45, debug= False):
    num = c_int(0)
    if debug: print("Assigned num")
    pnum = pointer(num)
    if debug: print("Assigned pnum")
    predict_image(net, im)
    if debug: print("did prediction")
    #dets = get_network_boxes(net, custom_image_bgr.shape[1], custom_image_bgr.shape[0], thresh, hier_thresh, None, 0, pnum, 0) # OpenCV
    dets = get_network_boxes(net, im.w, im.h, thresh, hier_thresh, None, 0, pnum, 0)
    if debug: print("Got dets")
    num = pnum[0]
    if debug: print("got zeroth index of pnum")
    if nms:
        do_nms_sort(dets, num, meta.classes, nms)
    if debug: print("did sort")
    res = []
    if debug: print("about to range")
    for j in range(num):
        if debug: print("Ranging on "+str(j)+" of "+str(num))
        if debug: print("Classes: "+str(meta), meta.classes, meta.names)
        for i in range(meta.classes):
            if debug: print("Class-ranging on "+str(i)+" of "+str(meta.classes)+"= "+str(dets[j].prob[i]))
            if dets[j].prob[i] > 0:
                b = dets[j].bbox
                if altNames is None:
                    nameTag = meta.names[i]
                else:
                    nameTag = altNames[i]
                if debug:
                    print("Got bbox", b)
                    print(nameTag)
                    print(dets[j].prob[i])
                    print((b.x, b.y, b.w, b.h))
                res.append((nameTag, dets[j].prob[i], (b.x, b.y, b.w, b.h)))
    if debug: print("did range")
    res = sorted(res, key=lambda x: -x[1])
    if debug: print("did sort")
    free_detections(dets, num)
    if debug: print("freed detections")
    return res

