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 15 import its.image 16 import its.device 17 import its.objects 18 import its.target 19 import sys 20 import numpy 21 import Image 22 import pprint 23 import math 24 import pylab 25 import os.path 26 import matplotlib 27 import matplotlib.pyplot 28 29 def main(): 30 """Test that device processing can be inverted to linear pixels. 31 32 Captures a sequence of shots with the device pointed at a uniform 33 target. Attempts to invert all the ISP processing to get back to 34 linear R,G,B pixel data. 35 """ 36 NAME = os.path.basename(__file__).split(".")[0] 37 38 NUM_STEPS = 5 39 40 # TODO: Query the allowable tonemap curve sizes; here, it's hardcoded to 41 # a length=64 list of tuples. The max allowed length should be inside the 42 # camera properties object. 43 L = 64 44 LM1 = float(L-1) 45 46 gamma_lut = numpy.array( 47 sum([[i/LM1, math.pow(i/LM1, 1/2.2)] for i in xrange(L)], [])) 48 inv_gamma_lut = numpy.array( 49 sum([[i/LM1, math.pow(i/LM1, 2.2)] for i in xrange(L)], [])) 50 51 with its.device.ItsSession() as cam: 52 expt,_ = its.target.get_target_exposure_combos(cam)["midSensitivity"] 53 props = cam.get_camera_properties() 54 sens_range = props['android.sensor.info.sensitivityRange'] 55 sens_step = (sens_range[1] - sens_range[0]) / float(NUM_STEPS-1) 56 sensitivities = [sens_range[0] + i * sens_step for i in range(NUM_STEPS)] 57 58 req = its.objects.manual_capture_request(0, expt) 59 req["android.blackLevel.lock"] = True 60 req["android.tonemap.mode"] = 0 61 req["android.tonemap.curveRed"] = gamma_lut.tolist() 62 req["android.tonemap.curveGreen"] = gamma_lut.tolist() 63 req["android.tonemap.curveBlue"] = gamma_lut.tolist() 64 65 r_means = [] 66 g_means = [] 67 b_means = [] 68 69 for sens in sensitivities: 70 req["android.sensor.sensitivity"] = sens 71 cap = cam.do_capture(req) 72 img = its.image.convert_capture_to_rgb_image(cap) 73 its.image.write_image( 74 img, "%s_sens=%04d.jpg" % (NAME, sens)) 75 img = its.image.apply_lut_to_image(img, inv_gamma_lut[1::2] * LM1) 76 tile = its.image.get_image_patch(img, 0.45, 0.45, 0.1, 0.1) 77 rgb_means = its.image.compute_image_means(tile) 78 r_means.append(rgb_means[0]) 79 g_means.append(rgb_means[1]) 80 b_means.append(rgb_means[2]) 81 82 pylab.plot(sensitivities, r_means, 'r') 83 pylab.plot(sensitivities, g_means, 'g') 84 pylab.plot(sensitivities, b_means, 'b') 85 86 pylab.ylim([0,1]) 87 matplotlib.pyplot.savefig("%s_plot_means.png" % (NAME)) 88 89 if __name__ == '__main__': 90 main() 91 92
