Add PygletThreadedImageViewer

checks/_io_checks/_pyglet_checks/check_pyglet_threaded_image_viewer.py

@@ -0,0 +1,15 @@
+#!/usr/bin/env python
+
+import imgviz
+
+from check_pyglet_imshow import get_images
+
+
+def main():
+    viewer = imgviz.io.PygletThreadedImageViewer(play=True)
+    for image in get_images():
+        viewer.imshow(image)
+
+
+if __name__ == '__main__':
+    main()

imgviz/_io/__init__.py

@@ -10,3 +10,4 @@
 
 from ._pyglet import pyglet_imshow
 from ._pyglet import pyglet_run
+from ._pyglet import PygletThreadedImageViewer

imgviz/_io/_pyglet/__init__.py

@@ -1,5 +1,16 @@
 # flake8: noqa
 
+from .base import check_pyglet_available
+
 from .pyglet_imshow import pyglet_imshow
 
 from .pyglet_run import pyglet_run
+
+try:
+    from .pyglet_threaded_image_viewer import PygletThreadedImageViewer
+except ImportError:
+
+    class PygletThreadedImageViewer(object):  # type: ignore
+
+        def __init__(self, *args, **kwargs):
+            check_pyglet_available()

imgviz/_io/_pyglet/pyglet_threaded_image_viewer.py

@@ -0,0 +1,87 @@
+import threading
+
+import pyglet
+
+from .pyglet_imshow import _ndarray_to_imagedata
+
+
+class PygletThreadedImageViewer(pyglet.window.Window):
+
+    def __init__(self, play=True, interval=0.5):
+        self._play = play
+        self._next = False
+
+        self._updated_at = 0
+        self._interval = interval
+
+        self.sprite = None
+
+        self.lock = threading.Lock()
+        self.thread = threading.Thread(target=self._init_and_start_app)
+        self.thread.daemon = True  # terminate when main thread exit
+        self.thread.start()
+
+        pyglet.clock.schedule_interval(self.on_update, 1 / 100)
+
+    def _init_and_start_app(self):
+        super(PygletThreadedImageViewer, self).__init__()
+        pyglet.app.run()
+
+    def imshow(self, image):
+        imagedata = _ndarray_to_imagedata(image)
+        with self.lock:
+            if self.sprite is None:
+                self.sprite = pyglet.sprite.Sprite(imagedata)
+            else:
+                self.sprite.image = imagedata
+            inserted_at = self._updated_at
+
+        while True:
+            with self.lock:
+                if self._play and \
+                        self._updated_at > (inserted_at + self._interval):
+                    break
+                elif self._next:
+                    self._next = False
+                    break
+
+    def on_draw(self):
+        self.clear()
+        self.sprite.draw()
+
+    def on_update(self, dt):
+        if self.sprite is None:
+            return
+        with self.lock:
+            self.on_draw()
+            self._updated_at += dt
+
+    def on_close(self):
+        pyglet.clock.unschedule(self.on_update)
+        with self.lock:
+            super(PygletThreadedImageViewer, self).on_close()
+
+    def on_key_press(self, symbol, modifiers):
+
+        def usage():
+            print('Usage: ')
+            print('  h: show help')
+            print('  q: close window')
+            print('  n: next image')
+            print('  s: toggle play')
+
+        def short_usage():
+            print("Press 'h' to show help")
+
+        if symbol == pyglet.window.key.H:
+            usage()
+        elif symbol == pyglet.window.key.Q:
+            self.on_close()
+        elif symbol == pyglet.window.key.S:
+            with self.lock:
+                self._play = not self._play
+        elif symbol == pyglet.window.key.N:
+            with self.lock:
+                self._next = True
+        else:
+            short_usage()