QLabel for image display, EXIF aware

qexifawareimage.py

from typing import *

import exifread
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *


class QExifAwareImage(QLabel):
    changed = pyqtSignal()

    _transformers = [
        lambda p: p,  # Normal
        lambda p: p.transformed(QTransform().scale(-1, 1)),  # Mirrored horizontal
        lambda p: p.transformed(QTransform().rotate(180)),  # Rotated 180
        lambda p: p.transformed(QTransform().scale(1, -1)),  # Mirrored vertical
        lambda p: p,  # Mirrored horizontal then rotated 90 CCW
        lambda p: p.transformed(QTransform().rotate(90)),  # Rotated 90 CW
        lambda p: p,  # Mirrored horizontal then rotated 90 CW
        lambda p: p.transformed(QTransform().rotate(-90))  # Rotated 90 CCW
    ]

    _exif = None

    def __init__(self, *args):
        super().__init__(*args)
        if not self.text():
            self.setText("No images loaded")

    def setImage(self, image: Union[str, QPixmap]) -> QPixmap:
        if type(image) is str:
            image = QPixmap(image)
        image = image.scaledToHeight(self.height())
        self.setFixedWidth(image.width())
        self.setPixmap(image)
        self.changed.emit()
        return image

    def setImageWithExif(self, image_path: str) -> QPixmap:
        with open(image_path, "rb") as f:
            exif = exifread.process_file(f, details=False, stop_tag="Image Orientation")
            if exif:
                self._exif = exif
                orientation = exif.get("Image Orientation")
                if orientation:
                    return self.setImage(self._transformers[orientation.values[0] - 1](QPixmap(image_path)))
            return self.setImage(QPixmap(image_path))

    def exif(self):
        return self._exif