1 # Copyright 2014 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 15 import its.image 16 import its.caps 17 import its.device 18 import its.objects 19 import os.path 20 import pylab 21 import matplotlib 22 import matplotlib.pyplot 23 import numpy 24 25 def main(): 26 """Tests that EV compensation is applied. 27 """ 28 NAME = os.path.basename(__file__).split(".")[0] 29 30 with its.device.ItsSession() as cam: 31 props = cam.get_camera_properties() 32 its.caps.skip_unless(its.caps.ev_compensation(props)) 33 34 ev_per_step = its.objects.rational_to_float( 35 props['android.control.aeCompensationStep']) 36 steps_per_ev = int(1.0 / ev_per_step) 37 evs = range(-2 * steps_per_ev, 2 * steps_per_ev + 1, steps_per_ev) 38 lumas = [] 39 for ev in evs: 40 # Re-converge 3A, and lock AE once converged. skip AF trigger as 41 # dark/bright scene could make AF convergence fail and this test 42 # doesn't care the image sharpness. 43 cam.do_3a(ev_comp=ev, lock_ae=True, do_af=False) 44 45 # Capture a single shot with the same EV comp and locked AE. 46 req = its.objects.auto_capture_request() 47 req['android.control.aeExposureCompensation'] = ev 48 req["android.control.aeLock"] = True 49 cap = cam.do_capture(req) 50 y = its.image.convert_capture_to_planes(cap)[0] 51 tile = its.image.get_image_patch(y, 0.45,0.45,0.1,0.1) 52 lumas.append(its.image.compute_image_means(tile)[0]) 53 54 pylab.plot(evs, lumas, 'r') 55 matplotlib.pyplot.savefig("%s_plot_means.png" % (NAME)) 56 57 # trim trailing 1.0s (for saturated image) 58 while lumas and lumas[-1] == 1.0: 59 lumas.pop(-1) 60 # Only allow positive EVs to give saturated image 61 assert(len(lumas) > 2) 62 luma_diffs = numpy.diff(lumas) 63 min_luma_diffs = min(luma_diffs) 64 print "Min of the luma value difference between adjacent ev comp: ", \ 65 min_luma_diffs 66 # All luma brightness should be increasing with increasing ev comp. 67 assert(min_luma_diffs > 0) 68 69 if __name__ == '__main__': 70 main() 71
