beginning of qt fancy imshow

scikits/image/io/_plugins/qt_plugin.py

@@ -14,7 +14,7 @@ except GuiLockError, gle:
 else:
     try:
         from PyQt4.QtGui import (QApplication, QMainWindow, QImage, QPixmap,
-                                 QLabel)
+                                 QLabel, QWidget, QVBoxLayout)
 
     except ImportError:
         print 'PyQT4 libraries not installed.  Plugin not loaded.'
@@ -24,19 +24,20 @@ else:
 
         app = None
 
+        class LabelImage(QLabel):
+            def __init__(self, parent, arr):
+                QLabel.__init__(self)
+                self.img = QImage(arr.data, arr.shape[1], arr.shape[0],
+                                  arr.strides[0], QImage.Format_RGB888)
+                self.pm = QPixmap.fromImage(self.img)
+                self.setPixmap(self.pm)
+
+
         class ImageWindow(QMainWindow):
             def __init__(self, arr, mgr):
                 QMainWindow.__init__(self)
                 self.mgr = mgr
-                img = QImage(arr.data, arr.shape[1], arr.shape[0],
-                             QImage.Format_RGB888)
-                pm = QPixmap.fromImage(img)
-
-                label = QLabel()
-                label.setPixmap(pm)
-                label.show()
-
-                self.label = label
+                self.label = LabelImage(self, arr)
                 self.setCentralWidget(self.label)
                 self.mgr.add_window(self)
 
@@ -45,7 +46,45 @@ else:
                 # references to it
                 self.mgr.remove_window(self)
 
-        def imshow(arr):
+
+        class FancyImageWindow(ImageWindow):
+            def __init__(self, arr, mgr):
+                ImageWindow.__init__(self, arr, mgr)
+
+                # we need to hold a reference to arr,
+                # if we want to access the data later,
+                # because QImage does not copy the data.
+                self.arr = arr
+
+                self.statusBar().showMessage('X: Y: ')
+                self.label.setScaledContents(True)
+                self.label.setMouseTracking(True)
+                self.label.mouseMoveEvent = self.label_mouseMoveEvent
+
+            def scale_mouse_pos(self, x, y):
+                width = self.label.width()
+                height = self.label.height()
+                x_frac = 1. * x / width
+                y_frac = 1. * y / height
+                width = self.arr.shape[1]
+                height = self.arr.shape[0]
+                new_x = int(width * x_frac)
+                new_y = int(height * y_frac)
+                return(new_x, new_y)
+
+            def label_mouseMoveEvent(self, evt):
+                x = evt.x()
+                y = evt.y()
+                x, y = self.scale_mouse_pos(x, y)
+                msg = 'X: %d, Y: %d  ' % (x, y)
+                R = self.arr[y,x,0]
+                G = self.arr[y,x,1]
+                B = self.arr[y,x,2]
+                msg += 'R: %s, G:, %s, B: %s' % (R, G, B)
+                self.statusBar().showMessage(msg)
+
+
+        def imshow(arr, fancy=False):
             global app
 
             if not app:
@@ -53,7 +92,11 @@ else:
 
             arr = prepare_for_display(arr)
 
-            iw = ImageWindow(arr, window_manager)
+            if not fancy:
+                iw = ImageWindow(arr, window_manager)
+            else:
+                iw = FancyImageWindow(arr, window_manager)
+
             iw.show()
 
         def _app_show():