1# Copyright 2013 The Android Open Source Project
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15import its.image
16import its.caps
17import its.device
18import its.objects
19import its.target
20import pylab
21import os.path
22import matplotlib
23import matplotlib.pyplot
24
25def main():
26    """Test that the android.sensor.exposureTime parameter is applied.
27    """
28    NAME = os.path.basename(__file__).split(".")[0]
29
30    exp_times = []
31    r_means = []
32    g_means = []
33    b_means = []
34
35    with its.device.ItsSession() as cam:
36        props = cam.get_camera_properties()
37        its.caps.skip_unless(its.caps.compute_target_exposure(props) and
38                             its.caps.per_frame_control(props))
39
40        e,s = its.target.get_target_exposure_combos(cam)["midExposureTime"]
41        for i,e_mult in enumerate([0.8, 0.9, 1.0, 1.1, 1.2]):
42            req = its.objects.manual_capture_request(s, e * e_mult, True, props)
43            cap = cam.do_capture(req)
44            img = its.image.convert_capture_to_rgb_image(cap)
45            its.image.write_image(
46                    img, "%s_frame%d.jpg" % (NAME, i))
47            tile = its.image.get_image_patch(img, 0.45, 0.45, 0.1, 0.1)
48            rgb_means = its.image.compute_image_means(tile)
49            exp_times.append(e * e_mult)
50            r_means.append(rgb_means[0])
51            g_means.append(rgb_means[1])
52            b_means.append(rgb_means[2])
53
54    # Draw a plot.
55    pylab.plot(exp_times, r_means, 'r')
56    pylab.plot(exp_times, g_means, 'g')
57    pylab.plot(exp_times, b_means, 'b')
58    pylab.ylim([0,1])
59    matplotlib.pyplot.savefig("%s_plot_means.png" % (NAME))
60
61    # Test for pass/fail: check that each shot is brighter than the previous.
62    for means in [r_means, g_means, b_means]:
63        for i in range(len(means)-1):
64            assert(means[i+1] > means[i])
65
66if __name__ == '__main__':
67    main()
68
69