| # 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.device |
| import its.objects |
| import pylab |
| import os.path |
| import matplotlib |
| import matplotlib.pyplot |
| import numpy |
| |
| def main(): |
| """Test that when the black level is locked, it doesn't change. |
| |
| Shoot with the camera covered (i.e.) dark/black. The test varies the |
| sensitivity parameter and checks if the black level changes. |
| """ |
| NAME = os.path.basename(__file__).split(".")[0] |
| |
| NUM_STEPS = 5 |
| |
| req = { |
| "android.blackLevel.lock": True, |
| "android.control.mode": 0, |
| "android.control.aeMode": 0, |
| "android.control.awbMode": 0, |
| "android.control.afMode": 0, |
| "android.sensor.frameDuration": 0, |
| "android.sensor.exposureTime": 10*1000*1000 |
| } |
| |
| # The most frequent pixel value in each image; assume this is the black |
| # level, since the images are all dark (shot with the lens covered). |
| modes = [] |
| |
| with its.device.ItsSession() as cam: |
| props = cam.get_camera_properties() |
| sens_range = props['android.sensor.info.sensitivityRange'] |
| sensitivities = range(sens_range[0], |
| sens_range[1]+1, |
| int((sens_range[1] - sens_range[0]) / NUM_STEPS)) |
| for si, s in enumerate(sensitivities): |
| req["android.sensor.sensitivity"] = s |
| cap = cam.do_capture(req) |
| yimg,_,_ = its.image.convert_capture_to_planes(cap) |
| hist,_ = numpy.histogram(yimg*255, 256, (0,256)) |
| modes.append(numpy.argmax(hist)) |
| |
| # Add this histogram to a plot; solid for shots without BL |
| # lock, dashes for shots with BL lock |
| pylab.plot(range(16), hist.tolist()[:16]) |
| |
| pylab.xlabel("Luma DN, showing [0:16] out of full [0:256] range") |
| pylab.ylabel("Pixel count") |
| pylab.title("Histograms for different sensitivities") |
| matplotlib.pyplot.savefig("%s_plot_histograms.png" % (NAME)) |
| |
| # Check that the black levels are all the same. |
| print "Black levels:", modes |
| assert(all([modes[i] == modes[0] for i in range(len(modes))])) |
| |
| if __name__ == '__main__': |
| main() |
| |