ImageCrop_Test_Graphics

import os
import sys

from PyQt5 import QtGui
from PyQt5 import QtWidgets
from PyQt5.QtCore import Qt, QEvent, QRectF, pyqtSignal, pyqtSlot, QRect
from PyQt5.QtGui import QPainter, QPen, QBrush, QPixmap, QImage
from PyQt5.QtWidgets import QGraphicsPixmapItem, QGraphicsRectItem, QFrame, QGraphicsView, QLabel
from PyQt5.QtWidgets import QApplication, QGraphicsScene, QMainWindow

import Ui_ImageCrop_Test # given here: https://pastebin.com/hgJjVjwy
import Ui_ImageROI_Test # given here: https://pastebin.com/A5CzwwVK


class ImageCrop(Ui_ImageCrop_Test.Ui_MainWindow, QMainWindow):
    formLife = pyqtSignal(bool)

    def __init__(self, parent=None):
        super(ImageCrop, self).__init__()
        self.setupUi(self)
        self.pushButton_1.clicked.connect(self.show_images)
        self.label_ID = 0
        self.img_files = ["Image1.jpg",
                          "Image2.jpg"]

        self.form2 = ImageROI(self)
        self.form3 = ImageROI(self)

        self.label_1.installEventFilter(self)
        self.label_2.installEventFilter(self)

    def show_images(self):
        self.form2 = ImageROI(self)
        self.form3 = ImageROI(self)
        labels = [self.label_1, self.label_2]
        for i, label, filename in zip(range(2), labels, self.img_files):
            image = QImage(filename)
            image = image.convertToFormat(QImage.Format_ARGB8565_Premultiplied)
            pixmap = QPixmap(image)
            w = int(label.width() - 4.0)
            h = int(label.height() - 4.0)
            smaller_pixmap = pixmap.scaled(w, h, Qt.IgnoreAspectRatio, Qt.FastTransformation)
            label.setPixmap(smaller_pixmap)
            label.setScaledContents(True)

    def eventFilter(self, source, event):
        labels = [self.label_1, self.label_2]
        forms = [self.form2, self.form3]
        if event.type() == QEvent.MouseButtonDblClick:
            if isinstance(source, QLabel) and source.pixmap() is not None:
                self.label_ID = labels.index(source)
                forms[self.label_ID].setImage(self.img_files[self.label_ID])
                forms[self.label_ID].show()
                forms[self.label_ID].formLife.connect(self.formRefresh)
        return super(ImageCrop, self).eventFilter(source, event)

    @pyqtSlot(bool)
    def formRefresh(self, status):
        if status:
            cropped_folder = "Cropped"
            newpath = os.path.join(cropped_folder, os.path.basename(self.img_files[self.label_ID]))
            self.img_files[self.label_ID] = newpath
            del self.form2
            del self.form3
            self.show_images()


class ImageROI(Ui_ImageROI_Test.Ui_MainWindow, QMainWindow):
    formLife = pyqtSignal(bool)

    def __init__(self, parent=None):
        super(ImageROI, self).__init__()
        self.setupUi(self)
        self.path = None
        self.pixmap = None

        self.pushButton_1.clicked.connect(self.click1)
        self.pushButton_2.clicked.connect(self.click2)

        # My Scene
        self.scene = QGraphicsScene()
        self.scene.clear()

        # My Image
        self.image_item = QGraphicsPixmapItem()

        # My ROI
        self.ROI_item = QGraphicsRectItem(self.image_item)
        self.ROI_item.setBrush(QBrush(Qt.NoBrush))
        self.ROI_item.setPen(QPen(Qt.white, 0, Qt.DashDotLine))

        # My View
        self.view = Click_QGraphicsView(self.graphicsView)
        self.view.setGeometry(self.geometry().x() + 10, self.geometry().y() + 29,
                              self.geometry().width() - 58, self.geometry().height() - 146)

                                # This part is a forced correction of my coordinates since my view and window are placed apart

        self.crop_ratio_w = 1
        self.crop_ratio_h = 1

        self.view.ROI_item = self.ROI_item
        self.view.setScene(self.scene)

        # My View attributes
        self.view.setBackgroundRole(QtGui.QPalette.Dark)
        self.view.setAlignment(Qt.AlignCenter)
        self.view.setFrameShape(QFrame.NoFrame)
        self.view.setRenderHint(QPainter.Antialiasing, False)
        self.view.setMouseTracking(True)

    def setImage(self, path):

        self.path = path
        self.pixmap = QPixmap(path)

        self.crop_ratio_w = self.pixmap.width() / self.view.width()
        self.crop_ratio_h = self.pixmap.height() / self.view.height()

        smaller_pixmap = self.pixmap.scaled(self.view.width(), self.view.height(),
                                            Qt.IgnoreAspectRatio, Qt.FastTransformation)
        self.image_item.setPixmap(smaller_pixmap)
        self.scene.addItem(self.image_item)
        self.scene.addItem(self.ROI_item)
        self.scene.setSceneRect(0, 0, self.view.width(), self.view.height())
        self.view.setGeometry(0, 0, self.view.width(), self.view.height())

        self.view.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
        self.view.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)

        self.view.setSceneSize()

    def click1(self):
        crop_rect = self.view.ROI_item.rect().toRect()
        crop_rect = QRect(crop_rect.x() * self.crop_ratio_w, crop_rect.y() * self.crop_ratio_h,
                          crop_rect.width() * self.crop_ratio_w, crop_rect.height() * self.crop_ratio_h)
        cropped = self.pixmap.copy(crop_rect)
        cropped_folder = "Cropped"
        newpath = os.path.join(cropped_folder, os.path.basename(self.path))
        cropped.save(newpath)
        self.close()
        if os.path.exists(newpath):
            self.formLife.emit(True)

    def click2(self):
        self.view.click = False
        self.view.selection = False
        self.close()

    def keyPressEvent(self, event):
        if event.key() == Qt.Key_Escape:
            rect = QRectF(0, 0, 0, 0)
            self.ROI_item.setRect(rect)
        event.accept()

    def mousePressEvent(self, event):
        rect = QRectF(0, 0, 0, 0)
        self.ROI_item.setRect(rect)

    def resizeEvent(self, event):
        self.view.setGeometry(self.geometry().x() + 10, self.geometry().y() + 29,
                              self.geometry().width() - 58, self.geometry().height() - 146)
        self.setImage(self.path)


class Click_QGraphicsView(QGraphicsView):
    scene_size = (0, 0)
    ROI_item = None
    event_origin = None
    event_pos = None
    selection = False
    click = False

    def mousePressEvent(self, event):
        self.click = True
        self.selection = True

        if self.selection:
            event_pos = self.mapToScene(event.pos())
            pos = (int(event_pos.x()), int(event_pos.y()))
            if 0 <= pos[0] < self.scene_size[0] and 0 <= pos[1] < self.scene_size[1]:
                self.event_origin = event_pos
            else:
                self.event_origin = None
            self.click = True
        else:
            QGraphicsView.mousePressEvent(self, event)

    def mouseMoveEvent(self, event):

        if self.event and self.click:
            self.selection = True

        event_pos = self.mapToScene((event.pos()))
        if self.selection and self.click:
            if self.event_origin:
                if event_pos.x() < 0:
                    event_pos.setX(0)
                elif event_pos.x() > self.scene_size[0] - 1:
                    event_pos.setX(self.scene_size[0] - 1)
                if event_pos.y() < 0:
                    event_pos.setY(0)
                elif event_pos.y() > self.scene_size[1] - 1:
                    event_pos.setY(self.scene_size[1] - 1)
                self.ROI_item.setRect(QRectF(self.event_origin, event_pos).normalized())
            else:
                pass
        else:
            QGraphicsView.mouseMoveEvent(self, event)

    def mouseReleaseEvent(self, event):
        if self.selection:
            self.click = False
            if self.event_origin:
                self.event_origin = None
        else:
            QGraphicsView.mouseReleaseEvent(self, event)

    def setSceneSize(self):
        rect = self.scene().sceneRect()
        self.scene_size = (rect.width(), rect.height())


def catch_exceptions(t, val, tb):
    QtWidgets.QMessageBox.critical(None,
                                   "An exception was raised",
                                   "Exception type: {}".format(t))
    old_hook(t, val, tb)


old_hook = sys.excepthook
sys.excepthook = catch_exceptions


def main():
    app = QApplication(sys.argv)
    form1 = ImageCrop()
    form1.show()
    app.exec_()
    del form1


if __name__ == '__main__': main()