utils.py

import os
import random
import time

import cv2
import numpy as np
import torch


def seed_everything(**args):
    """Seed everything for better reproducibility.
    NOTE that some pytorch operation is non-deterministic like the backprop of grid_samples
    """
    seed = args.get("seed", 42)
    torch.manual_seed(seed)
    np.random.seed(seed)
    random.seed(seed)


def draw_red_point_bbox_based_on_center(image_np):
    """Draw a red point in the center of the image"""
    height, width = image_np.shape[:2]
    center = (
        width // 2,
        height // 2,
    )
    bbox = (
        center[0] - width // 2,
        center[1] - height // 2,
        center[0] + width // 2,
        center[1] + height // 2,
    )
    # cv2 to draw bbox
    image_np = cv2.rectangle(
        image_np, (bbox[0], bbox[1]), (bbox[2], bbox[3]), (0, 0, 255), 2
    )

    image_np[center[1], center[0]] = [255, 0, 0]
    return image_np


def draw_center_bbox(image_np, center, bbox):
    """Draw a red point in the center of the image"""
    image_np[center[0], center[1]] = [255, 0, 0]
    # cv2 to draw bbox
    image_np = cv2.rectangle(
        image_np, (bbox[0], bbox[1]), (bbox[2], bbox[3]), (0, 0, 255), 2
    )
    return image_np


class VideoWriter:
    def __init__(
        self,
        out_dir,
        name,
    ):
        if not os.path.exists(out_dir):
            os.makedirs(out_dir)

        self.name = name

        timestamp = int(time.time())
        self.fn = "{}_{}.mp4".format(
            self.name,
            timestamp,
        )

        self.out = os.path.join(out_dir, self.fn)
        self.output_file = None

    def __call__(self, frame):
        if self.output_file is None:
            height, width, _ = frame.shape
            self.output_file = cv2.VideoWriter(
                self.out, cv2.VideoWriter_fourcc(*"mp4v"), 20.0, (width, height)
            )
        self.output_file.write(frame)

    def release(self):
        self.output_file.release()