Show image's color gamut

beeref/actions/actions.py

@@ -265,6 +265,12 @@ actions = ActionList([
         'callback': 'on_action_grayscale',
         'group': 'active_when_selection',
     }),
+    Action({
+        'id': 'show_color_gamut',
+        'text': 'Show &Color Gamut',
+        'callback': 'on_action_show_color_gamut',
+        'group': 'active_when_single_image',
+    }),
     Action({
         'id': 'crop',
         'text': '&Crop',

beeref/actions/menu_structure.py

@@ -108,6 +108,8 @@ menu_structure = [
         'items': [
             'change_opacity',
             'grayscale',
+            MENU_SEPARATOR,
+            'show_color_gamut',
         ],
     },
     {

beeref/items.py

@@ -17,6 +17,8 @@
 text).
 """
 
+from collections import defaultdict
+from functools import cached_property
 import logging
 
 from PyQt6 import QtCore, QtGui, QtWidgets
@@ -211,6 +213,41 @@ class BeePixmapItem(BeeItemMixin, QtWidgets.QGraphicsPixmapItem):
         item.crop = self.crop
         return item
 
+    @cached_property
+    def color_gamut(self):
+        logger.debug(f'Calculating color gamut for {self}')
+        gamut = defaultdict(int)
+        img = self.pixmap().toImage()
+        # Don't evaluate every pixel for larger images:
+        step = max(1, int(max(img.width(), img.height()) / 1000))
+        logger.debug(f'Considering every {step}. row/column')
+
+        # Not actually faster than solution below :(
+        # ptr = img.bits()
+        # size = img.sizeInBytes()
+        # pixelsize = int(img.sizeInBytes() / img.width() / img.height())
+        # ptr.setsize(size)
+        # for pixel in batched(ptr, n=pixelsize):
+        #     r, g, b, alpha = tuple(map(ord, pixel))
+        #     if 5 < alpha and 5 < r < 250 and 5 < g < 250 and 5 < b < 250:
+        #         # Only consider pixels that aren't close to
+        #         # transparent, white or black
+        #         rgb = QtGui.QColor(r, g, b)
+        #         gamut[rgb.hue(), rgb.saturation()] += 1
+
+        for i in range(0, img.width(), step):
+            for j in range(0, img.height(), step):
+                rgb = img.pixelColor(i, j)
+                rgbtuple = (rgb.red(), rgb.blue(), rgb.green())
+                if (5 < rgb.alpha()
+                        and min(rgbtuple) < 250 and max(rgbtuple) > 5):
+                    # Only consider pixels that aren't close to
+                    # transparent, white or black
+                    gamut[rgb.hue(), rgb.saturation()] += 1
+
+        logger.debug(f'Got {len(gamut)} color gamut values')
+        return gamut
+
     def copy_to_clipboard(self, clipboard):
         clipboard.setPixmap(self.pixmap())
 

beeref/view.py

@@ -329,6 +329,9 @@ class BeeGraphicsView(MainControlsMixin,
         self.undo_stack.push(commands.ResetTransforms(
             self.scene.selectedItems(user_only=True)))
 
+    def on_action_show_color_gamut(self):
+        widgets.color_gamut.GamutDialog(self, self.scene.selectedItems()[0])
+
     def on_items_loaded(self, value):
         logger.debug('On items loaded: add queued items')
         self.scene.add_queued_items()

beeref/widgets/__init__.py

@@ -21,7 +21,7 @@ from PyQt6.QtCore import Qt
 
 from beeref import constants, commands
 from beeref.config import logfile_name
-from beeref.widgets import settings, welcome_overlay  # noqa: F401
+from beeref.widgets import settings, welcome_overlay, color_gamut  # noqa: F401
 
 
 logger = logging.getLogger(__name__)

beeref/widgets/color_gamut.py

@@ -0,0 +1,140 @@
+# This file is part of BeeRef.
+#
+# BeeRef is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
+import logging
+import math
+
+from PyQt6 import QtWidgets, QtGui, QtCore
+from PyQt6.QtCore import Qt
+
+
+logger = logging.getLogger(__name__)
+
+
+class GamutPainterThread(QtCore.QThread):
+    """Dedicated thread for drawing the gamut image."""
+
+    finished = QtCore.pyqtSignal(QtGui.QImage)
+    radius = 250
+
+    def __init__(self, parent, item):
+        super().__init__()
+        self.item = item
+        self.parent = parent
+
+    def run(self):
+        logger.debug('Start drawing gamut image...')
+        self.image = QtGui.QImage(
+            QtCore.QSize(2 * self.radius, 2 * self.radius),
+            QtGui.QImage.Format.Format_ARGB32)
+        self.image.fill(QtGui.QColor(0, 0, 0, 0))
+
+        painter = QtGui.QPainter(self.image)
+        painter.setRenderHint(QtGui.QPainter.RenderHint.Antialiasing)
+        painter.setBrush(QtGui.QBrush(QtGui.QColor(0, 0, 0)))
+        painter.setPen(Qt.PenStyle.NoPen)
+        center = QtCore.QPoint(self.radius, self.radius)
+        painter.drawEllipse(center, self.radius, self.radius)
+        logger.debug(f'Threshold: {self.parent.threshold}')
+
+        for (hue, saturation), count in self.item.color_gamut.items():
+            if count < self.parent.threshold:
+                continue
+            hypotenuse = saturation / 255 * self.radius
+            angle = math.radians(-90 - hue)
+            x = int(math.sin(angle) * hypotenuse) + center.x()
+            y = int(math.cos(angle) * hypotenuse) + center.y()
+            color = QtGui.QColor()
+            color.setHsv(hue, saturation, 255)
+            painter.setBrush(QtGui.QBrush(color))
+            painter.drawEllipse(QtCore.QPoint(x, y), 3, 3)
+
+        logger.debug('Finished drawing gamut image.')
+        self.finished.emit(self.image)
+
+
+class GamutWidget(QtWidgets.QWidget):
+
+    def __init__(self, parent, item):
+        super().__init__(parent)
+        self.item = item
+        self.image = None
+        self.worker = GamutPainterThread(self, item)
+        self.worker.finished.connect(self.on_gamut_finished)
+        self.worker.start()
+
+    @property
+    def threshold(self):
+        return self.parent().threshold_input.value()
+
+    def on_gamut_finished(self, image):
+        logger.debug('Gamut image update received')
+        self.image = image
+        self.update()
+
+    def minimumSizeHint(self):
+        return QtCore.QSize(200, 200)
+
+    def update_values(self):
+        self.worker.start()
+
+    def paintEvent(self, event):
+        painter = QtGui.QPainter(self)
+        painter.setRenderHint(painter.RenderHint.SmoothPixmapTransform)
+        if self.image:
+            size = min(self.size().width(), self.size().height())
+            x = max((self.size().width() - size) / 2, 0)
+            y = max((self.size().height() - size) / 2, 0)
+            painter.drawImage(QtCore.QRectF(x, y, size, size), self.image)
+        else:
+            painter.drawText(10, 20, 'Counting pixels...')
+
+
+class GamutDialog(QtWidgets.QDialog):
+    def __init__(self, parent, item):
+        super().__init__(parent)
+        self.item = item
+        self.setWindowTitle('Color Gamut')
+
+        # The input controls on the right
+        controls_layout = QtWidgets.QVBoxLayout()
+
+        label = QtWidgets.QLabel('Threshold:', self)
+        controls_layout.addWidget(label)
+        self.threshold_input = QtWidgets.QSlider(self)
+        self.threshold_input.setRange(0, 500)
+        self.threshold_input.setValue(20)
+        self.threshold_input.setTracking(False)
+        self.threshold_input.valueChanged.connect(self.on_value_changed)
+        controls_layout.addWidget(
+            self.threshold_input, alignment=Qt.AlignmentFlag.AlignHCenter)
+
+        buttons = QtWidgets.QDialogButtonBox(
+            QtWidgets.QDialogButtonBox.StandardButton.Close)
+        buttons.rejected.connect(self.reject)
+
+        controls_layout.addWidget(buttons)
+
+        # The gamut display
+        layout = QtWidgets.QHBoxLayout()
+        self.setLayout(layout)
+        self.gamut_widget = GamutWidget(self, item)
+        layout.addWidget(self.gamut_widget, stretch=1)
+
+        layout.addLayout(controls_layout, stretch=0)
+        self.show()
+
+    def on_value_changed(self, value):
+        self.gamut_widget.update_values()

tests/items/test_pixmapitem.py

@@ -377,6 +377,37 @@ def test_create_copy(qapp, imgfilename3x3):
     assert copy.grayscale is True
 
 
+def test_color_gamut_finds_colors(qapp):
+    img = QtGui.QImage(10, 10, QtGui.QImage.Format.Format_ARGB32)
+    img.fill(QtGui.QColor(0, 0, 0))
+    img.setPixelColor(1, 1, QtGui.QColor(255, 0, 0))
+    img.setPixelColor(5, 5, QtGui.QColor(0, 255, 0))
+    img.setPixelColor(5, 6, QtGui.QColor(0, 50, 0))
+    item = BeePixmapItem(img, 'foo.png')
+    assert item.color_gamut == {(0, 255): 1, (120, 255): 2}
+
+
+def test_color_gamut_ignores_almost_black(qapp):
+    img = QtGui.QImage(10, 10, QtGui.QImage.Format.Format_ARGB32)
+    img.fill(QtGui.QColor(3, 3, 3))
+    item = BeePixmapItem(img, 'foo.png')
+    assert item.color_gamut == {}
+
+
+def test_color_gamut_ignores_almost_white(qapp):
+    img = QtGui.QImage(10, 10, QtGui.QImage.Format.Format_ARGB32)
+    img.fill(QtGui.QColor(253, 253, 253))
+    item = BeePixmapItem(img, 'foo.png')
+    assert item.color_gamut == {}
+
+
+def test_color_gamut_ignores_almost_transparent(qapp):
+    img = QtGui.QImage(10, 10, QtGui.QImage.Format.Format_ARGB32)
+    img.fill(QtGui.QColor(255, 0, 0, 3))
+    item = BeePixmapItem(img, 'foo.png')
+    assert item.color_gamut == {}
+
+
 def test_copy_to_clipboard(qapp, imgfilename3x3):
     clipboard = QtWidgets.QApplication.clipboard()
     item = BeePixmapItem(QtGui.QImage(imgfilename3x3), 'foo.png')

tests/widgets/test_color_gamut.py

@@ -0,0 +1,61 @@
+from unittest.mock import MagicMock
+
+from PyQt6 import QtGui
+
+from beeref.items import BeePixmapItem
+from beeref.widgets.color_gamut import (
+    GamutDialog,
+    GamutPainterThread,
+    GamutWidget,
+)
+
+
+def test_gamut_painter_thread_generates_image(view, imgfilename3x3):
+    item = BeePixmapItem(QtGui.QImage(imgfilename3x3))
+    view.scene.addItem(item)
+    dialog = GamutDialog(view, item)
+    dialog.threshold_input.setValue(0)
+    widget = GamutWidget(dialog, item)
+    worker = GamutPainterThread(widget, item)
+    mock = MagicMock()
+    worker.finished.connect(mock)
+    worker.run()
+
+    mock.assert_called_once()
+    image = mock.call_args[0][0]
+    assert image.size().width() == 500
+    assert image.size().height() == 500
+    assert image.allGray() is False
+
+
+def test_gamut_painter_thread_generates_image_below_threshold(
+        view, imgfilename3x3):
+    item = BeePixmapItem(QtGui.QImage(imgfilename3x3))
+    view.scene.addItem(item)
+    dialog = GamutDialog(view, item)
+    dialog.threshold_input.setValue(20)
+    widget = GamutWidget(dialog, item)
+    worker = GamutPainterThread(widget, item)
+    mock = MagicMock()
+    worker.finished.connect(mock)
+    worker.run()
+
+    mock.assert_called_once()
+    image = mock.call_args[0][0]
+    assert image.size().width() == 500
+    assert image.size().height() == 500
+    assert image.allGray() is True
+
+
+def test_gamut_widget_generates_image(view, imgfilename3x3, qtbot):
+    item = BeePixmapItem(QtGui.QImage(imgfilename3x3))
+    view.scene.addItem(item)
+    dialog = GamutDialog(view, item)
+    dialog.threshold_input.setValue(0)
+    widget = GamutWidget(dialog, item)
+    assert widget.image is None
+    widget.show()
+    qtbot.waitUntil(lambda: widget.image is not None)
+    assert widget.image.size().width() == 500
+    assert widget.image.size().height() == 500
+    assert widget.image.allGray() is False