detection_utils.py

from tkinter import W
import gradio as gr
from matplotlib import cm
import torch
import torchvision
import matplotlib
import PIL
from PIL import Image, ImageColor, ImageFont, ImageDraw 
import numpy as np
import math


import yaml
import pdb

############################################
# Predict detections with MegaDetector v5a model
def predict_md(im, 
               megadetector_model, #Megadet_Models[mega_model_input]
               size=640):
               
    # resize image
    g = (size / max(im.size))  # multipl factor to make max size of the image equal to input size
    im = im.resize((int(x * g) for x in im.size), 
                    PIL.Image.Resampling.LANCZOS)  # resize
    # device
    if torch.cuda.is_available():
        md_device = torch.device('cuda')
    else:
        md_device = torch.device('cpu')

    # megadetector    
    MD_model = torch.hub.load('ultralytics/yolov5', # repo_or_dir
                              'custom', #model
                              megadetector_model, # args for callable model
                              force_reload=True,
                              device=md_device) 
                              
    # send model to gpu if possible
    if (md_device == torch.device('cuda')):
        print('Sending model to GPU')
        MD_model.to(md_device)    

    ## detect objects
    results = MD_model(im)  # inference # vars(results).keys()= dict_keys(['imgs', 'pred', 'names', 'files', 'times', 'xyxy', 'xywh', 'xyxyn', 'xywhn', 'n', 't', 's'])
    
    return results  


##########################################
def crop_animal_detections(img_in,
                           yolo_results, 
                           likelihood_th):

    ## Extract animal crops
    list_labels_as_str = [i for i in yolo_results.names.values()]  # ['animal', 'person', 'vehicle'] 
    list_np_animal_crops = []

    # image to crop (scale as input for megadetector)
    img_in = img_in.resize((yolo_results.ims[0].shape[1],
                            yolo_results.ims[0].shape[0]))
    # for every detection in the img                        
    for det_array in yolo_results.xyxy:

        # for every detection
        for j in range(det_array.shape[0]):

            # compute coords around bbox rounded to the nearest integer (for pasting later)
            xmin_rd = int(math.floor(det_array[j,0])) # int() should suffice?
            ymin_rd = int(math.floor(det_array[j,1]))

            xmax_rd = int(math.ceil(det_array[j,2]))
            ymax_rd = int(math.ceil(det_array[j,3]))

            pred_llk = det_array[j,4] 
            pred_label = det_array[j,5]
            # keep animal crops above threshold
            if (pred_label == list_labels_as_str.index('animal')) and \
                (pred_llk >= likelihood_th):
                area = (xmin_rd, ymin_rd, xmax_rd, ymax_rd)

                #pdb.set_trace()
                crop = img_in.crop(area) #Image.fromarray(img_in).crop(area)
                crop_np = np.asarray(crop)

                # add to list
                list_np_animal_crops.append(crop_np)

    return list_np_animal_crops