utils/functional.py

import os
import random
from typing import Union

import albumentations as A
import cv2
import numpy as np
import pytorch_lightning as pl
import streamlit as st
import torch
from albumentations.pytorch import ToTensorV2

from . import configs


def generate_empty_space(total_space: int = 1) -> None:
    for _ in range(total_space):
        st.write("")


def set_page_config(page_title: str, page_icon: str) -> None:
    st.set_page_config(
        page_title=f"{configs.APP_NAME} - {page_title}",
        page_icon="🚀",
        layout="wide",
        initial_sidebar_state="collapsed",
    )
    st.title(f"{page_icon} {page_title}")
    st.caption(f"Created by: {configs.AUTHOR_NAME}")


def set_seed(seed: int = configs.RANDOM_SEED) -> None:
    torch.manual_seed(seed)
    torch.cuda.manual_seed_all(seed)
    torch.cuda.manual_seed(seed)
    torch.backends.cudnn.deterministic = True
    torch.backends.cudnn.benchmark = False
    np.random.seed(seed)
    random.seed(seed)
    os.environ["PYTHONHASHSEED"] = str(seed)
    pl.seed_everything(seed)


def euclidean_distance_normalized(x: np.ndarray, y: np.ndarray) -> np.float32:
    distance = np.linalg.norm(x - y)
    normalized_distance = 1 / (1 + distance)
    return normalized_distance


def image_augmentations(image_size: int = configs.SIZE_IMAGES) -> A.Compose:
    return A.Compose(
        (
            A.Resize(image_size, image_size),
            A.Normalize(
                mean=configs.NORMALIZE_IMAGE_MEAN, std=configs.NORMALIZE_IMAGE_STD
            ),
            ToTensorV2(),
        )
    )


def normalize_image_to_zero_one(x: np.ndarray) -> np.ndarray:
    return np.array((x - np.min(x)) / (np.max(x) - np.min(x)))


def reshape_transform(
    tensor: torch.Tensor, height: int = 14, width: int = 14
) -> torch.Tensor:
    result = tensor[:, 1:, :].reshape(tensor.size(0), height, width, tensor.size(2))
    result = result.transpose(2, 3).transpose(1, 2)
    return result


def get_device() -> torch.device:
    return torch.device("cuda" if torch.cuda.is_available() else "cpu")


def get_default_images() -> tuple:
    return_images = []
    class_characters = os.listdir(configs.DEFAULT_IMAGES_PATH)
    for cls in class_characters:
        images_characters = os.listdir(os.path.join(configs.DEFAULT_IMAGES_PATH, cls))
        for image in images_characters:
            return_images.append(
                os.path.join(configs.DEFAULT_IMAGES_PATH, cls, image).replace("\\", "/")
            )

    return tuple(return_images)


def check_data_type_variable(data, data_type):
    if not isinstance(data, data_type):
        raise TypeError(f"Data must be {data_type} type")


def get_most_salient_object(image: np.ndarray) -> np.ndarray:
    saliency = cv2.saliency.StaticSaliencyFineGrained_create()
    _, saliency_map = saliency.computeSaliency(image)
    saliency_map = (saliency_map * 255).astype("uint8")
    thresh_map = cv2.threshold(
        saliency_map, 0, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU
    )[1]
    return thresh_map


def margin_confidence(prob_dist: np.ndarray, sorted: bool = False) -> np.ndarray:
    if not sorted:
        prob_dist[::-1].sort()
    difference = prob_dist[0] - prob_dist[1]
    margin_conf = 1 - difference
    return margin_conf


def ratio_confidence(prob_dist: np.ndarray, sorted: bool = False) -> np.ndarray:
    if not sorted:
        prob_dist[::-1].sort()
    ratio_conf = prob_dist[1] / prob_dist[0]
    return ratio_conf


def least_confidence(prob_dist: np.ndarray, sorted: bool = False) -> np.ndarray:
    if sorted:
        simple_least_conf = prob_dist[0]
    else:
        simple_least_conf = np.nanmax(prob_dist)
    num_labels = float(prob_dist.size)
    normalized_least_conf = (1 - simple_least_conf) * (num_labels / (num_labels - 1))
    return normalized_least_conf


def entropy_score(prob_dist: np.ndarray) -> np.ndarray:
    log_probs = prob_dist * np.log2(prob_dist)
    raw_entropy = 0 - np.sum(log_probs)
    normalized_entropy = raw_entropy / np.log2(prob_dist.size)
    return normalized_entropy


def active_learning_uncertainty(prob_dist: np.ndarray) -> Union[np.ndarray, bool]:
    result_margin_confidence = margin_confidence(prob_dist)
    has_nan = np.isnan(result_margin_confidence).any()
    if has_nan:
        return False
    result_ratio_confidence = ratio_confidence(prob_dist)
    has_nan = np.isnan(result_ratio_confidence).any()
    if has_nan:
        return result_margin_confidence
    result_least_confidence = least_confidence(prob_dist)
    has_nan = np.isnan(result_least_confidence).any()
    if has_nan:
        return np.mean([result_margin_confidence, result_ratio_confidence])
    result_entropy_score = entropy_score(prob_dist)
    has_nan = np.isnan(result_entropy_score).any()
    if has_nan:
        return np.mean([result_margin_confidence, result_ratio_confidence, result_least_confidence])
    return np.mean([result_margin_confidence, result_ratio_confidence, result_least_confidence, result_entropy_score])