camera2: Move ITS tests to CTS verifier.

Bug: 17994909

Change-Id: Ie788b1ae3a6b079e37a3472c46aed3dfdcfffe2c
diff --git a/apps/CameraITS/tests/scene1/test_exposure.py b/apps/CameraITS/tests/scene1/test_exposure.py
new file mode 100644
index 0000000..8676358
--- /dev/null
+++ b/apps/CameraITS/tests/scene1/test_exposure.py
@@ -0,0 +1,92 @@
+# Copyright 2013 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import its.image
+import its.caps
+import its.device
+import its.objects
+import its.target
+import pylab
+import numpy
+import os.path
+import matplotlib
+import matplotlib.pyplot
+
+def main():
+    """Test that a constant exposure is seen as ISO and exposure time vary.
+
+    Take a series of shots that have ISO and exposure time chosen to balance
+    each other; result should be the same brightness, but over the sequence
+    the images should get noisier.
+    """
+    NAME = os.path.basename(__file__).split(".")[0]
+
+    THRESHOLD_MAX_OUTLIER_DIFF = 0.1
+    THRESHOLD_MIN_LEVEL = 0.1
+    THRESHOLD_MAX_LEVEL = 0.9
+    THRESHOLD_MAX_ABS_GRAD = 0.001
+
+    mults = []
+    r_means = []
+    g_means = []
+    b_means = []
+
+    with its.device.ItsSession() as cam:
+        props = cam.get_camera_properties()
+        if not its.caps.compute_target_exposure(props):
+            print "Test skipped"
+            return
+
+        e,s = its.target.get_target_exposure_combos(cam)["minSensitivity"]
+        expt_range = props['android.sensor.info.exposureTimeRange']
+        sens_range = props['android.sensor.info.sensitivityRange']
+
+        m = 1
+        while s*m < sens_range[1] and e/m > expt_range[0]:
+            mults.append(m)
+            req = its.objects.manual_capture_request(s*m, e/m)
+            cap = cam.do_capture(req)
+            img = its.image.convert_capture_to_rgb_image(cap)
+            its.image.write_image(img, "%s_mult=%02d.jpg" % (NAME, m))
+            tile = its.image.get_image_patch(img, 0.45, 0.45, 0.1, 0.1)
+            rgb_means = its.image.compute_image_means(tile)
+            r_means.append(rgb_means[0])
+            g_means.append(rgb_means[1])
+            b_means.append(rgb_means[2])
+            m = m + 4
+
+    # Draw a plot.
+    pylab.plot(mults, r_means, 'r')
+    pylab.plot(mults, g_means, 'g')
+    pylab.plot(mults, b_means, 'b')
+    pylab.ylim([0,1])
+    matplotlib.pyplot.savefig("%s_plot_means.png" % (NAME))
+
+    # Check for linearity. For each R,G,B channel, fit a line y=mx+b, and
+    # assert that the gradient is close to 0 (flat) and that there are no
+    # crazy outliers. Also ensure that the images aren't clamped to 0 or 1
+    # (which would make them look like flat lines).
+    for chan in xrange(3):
+        values = [r_means, g_means, b_means][chan]
+        m, b = numpy.polyfit(mults, values, 1).tolist()
+        print "Channel %d line fit (y = mx+b): m = %f, b = %f" % (chan, m, b)
+        assert(abs(m) < THRESHOLD_MAX_ABS_GRAD)
+        assert(b > THRESHOLD_MIN_LEVEL and b < THRESHOLD_MAX_LEVEL)
+        for v in values:
+            assert(v > THRESHOLD_MIN_LEVEL and v < THRESHOLD_MAX_LEVEL)
+            assert(abs(v - b) < THRESHOLD_MAX_OUTLIER_DIFF)
+
+if __name__ == '__main__':
+    main()
+