Camera dummy added

.gitignore

@@ -1,2 +1,8 @@
 photobooth.cfg
 photobooth/__pycache__
+photobooth/*/__pycache__
+.eggs
+.venv
+photobooth.egg-info
+*.log
+*.log.*

photobooth/camera/CameraDummy.py

@@ -0,0 +1,115 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+import logging
+import math
+import random
+
+from PIL import Image
+
+from . import Camera
+
+
+class CameraDummy(Camera):
+
+    def __init__(self):
+
+        super().__init__()
+
+        self.hasPreview = True
+        self.hasIdle = False
+
+        random.seed()
+
+        logging.info('Using CameraDummy')
+
+    def getPreview(self):
+
+        return self.getPicture()
+
+    def getPicture(self):
+
+        return plotColor(buildExpr(), buildExpr(), buildExpr())
+
+
+# The following codes were taken from
+# https://github.com/j2kun/random-art/blob/master/randomart.py to generate some
+# psychedelic random pictures for testing purposes.
+
+class X:
+
+    def eval(self, x, y):
+
+      return x
+
+class Y:
+
+    def eval(self, x, y):
+
+        return y
+
+
+class SinPi:
+
+    def __init__(self, prob):
+
+        self.arg = buildExpr(prob * prob)
+
+    def eval(self, x, y):
+
+        return math.sin(math.pi * self.arg.eval(x,y))
+
+
+class CosPi:
+
+    def __init__(self, prob):
+
+        self.arg = buildExpr(prob * prob)
+
+    def eval(self, x, y):
+
+        return math.cos(math.pi * self.arg.eval(x,y))
+
+
+class Times:
+
+    def __init__(self, prob):
+
+        self.lhs = buildExpr(prob * prob)
+        self.rhs = buildExpr(prob * prob)
+
+    def eval(self, x, y):
+
+        return self.lhs.eval(x,y) * self.rhs.eval(x,y)
+
+def buildExpr(prob = 0.99):
+
+    if random.random() < prob:
+        return random.choice([SinPi, CosPi, Times])(prob)
+    else:
+        return random.choice([X, Y])()
+
+def plotIntensity(exp, pixelsPerUnit = 150):
+
+    canvasWidth = 2 * pixelsPerUnit + 1
+    canvas = Image.new("L", (canvasWidth, canvasWidth))
+
+    for py in range(canvasWidth):
+        for px in range(canvasWidth):
+            # Convert pixel location to [-1,1] coordinates
+            x = float(px - pixelsPerUnit) / pixelsPerUnit 
+            y = -float(py - pixelsPerUnit) / pixelsPerUnit
+            z = exp.eval(x,y)
+
+            # Scale [-1,1] result to [0,255].
+            intensity = int(z * 127.5 + 127.5)
+            canvas.putpixel((px,py), intensity)
+
+    return canvas
+
+def plotColor(redExp, greenExp, blueExp, pixelsPerUnit = 150):
+
+    redPlane   = plotIntensity(redExp, pixelsPerUnit)
+    greenPlane = plotIntensity(greenExp, pixelsPerUnit)
+    bluePlane  = plotIntensity(blueExp, pixelsPerUnit)
+    return Image.merge("RGB", (redPlane, greenPlane, bluePlane))

photobooth/camera/__init__.py

@@ -8,7 +8,8 @@ modules = (
     ('gphoto2-cffi', 'CameraGphoto2Cffi', 'CameraGphoto2Cffi'),
     ('gphoto2-commandline', 'CameraGphoto2CommandLine',
      'CameraGphoto2CommandLine'),
-    ('opencv', 'CameraOpenCV', 'CameraOpenCV'))
+    ('opencv', 'CameraOpenCV', 'CameraOpenCV'),
+    ('dummy', 'CameraDummy', 'CameraDummy'))
 
 
 class Camera: