# 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 math
import os.path

import its.caps
import its.device
import its.image
import its.objects
import its.target

import matplotlib.pylab
import matplotlib.pyplot

NAME = os.path.basename(__file__).split(".")[0]
THRESHOLD_MAX_RMS_DIFF = 0.03


def main():
    """Test that the reported sizes and formats for image capture work.
    """

    with its.device.ItsSession() as cam:
        props = cam.get_camera_properties()
        its.caps.skip_unless(its.caps.compute_target_exposure(props) and
                             its.caps.per_frame_control(props))

        # Use a manual request with a linear tonemap so that the YUV and JPEG
        # should look the same (once converted by the its.image module).
        e, s = its.target.get_target_exposure_combos(cam)["midExposureTime"]
        req = its.objects.manual_capture_request(s, e, 0.0, True, props)

        rgbs = []

        for size in its.objects.get_available_output_sizes("yuv", props):
            out_surface = {"width": size[0], "height": size[1], "format": "yuv"}
            cap = cam.do_capture(req, out_surface)
            assert cap["format"] == "yuv"
            assert cap["width"] == size[0]
            assert cap["height"] == size[1]
            print "Captured YUV %dx%d" % (cap["width"], cap["height"]),
            img = its.image.convert_capture_to_rgb_image(cap)
            its.image.write_image(img, "%s_yuv_w%d_h%d.jpg"%(
                    NAME, size[0], size[1]))
            tile = its.image.get_image_patch(img, 0.45, 0.45, 0.1, 0.1)
            rgb = its.image.compute_image_means(tile)
            print "rgb =", rgb
            rgbs.append(rgb)

        for size in its.objects.get_available_output_sizes("jpg", props):
            out_surface = {"width": size[0], "height": size[1], "format": "jpg"}
            cap = cam.do_capture(req, out_surface)
            assert cap["format"] == "jpeg"
            assert cap["width"] == size[0]
            assert cap["height"] == size[1]
            img = its.image.decompress_jpeg_to_rgb_image(cap["data"])
            its.image.write_image(img, "%s_jpg_w%d_h%d.jpg"%(
                    NAME, size[0], size[1]))
            assert img.shape[0] == size[1]
            assert img.shape[1] == size[0]
            assert img.shape[2] == 3
            print "Captured JPEG %dx%d" % (cap["width"], cap["height"]),
            tile = its.image.get_image_patch(img, 0.45, 0.45, 0.1, 0.1)
            rgb = its.image.compute_image_means(tile)
            print "rgb =", rgb
            rgbs.append(rgb)

        # Plot means vs format
        matplotlib.pylab.title(NAME)
        matplotlib.pylab.plot(range(len(rgbs)), [r[0] for r in rgbs], "-ro")
        matplotlib.pylab.plot(range(len(rgbs)), [g[1] for g in rgbs], "-go")
        matplotlib.pylab.plot(range(len(rgbs)), [b[2] for b in rgbs], "-bo")
        matplotlib.pylab.ylim([0, 1])
        matplotlib.pylab.xlabel("format number")
        matplotlib.pylab.ylabel("RGB avg [0, 1]")
        matplotlib.pyplot.savefig("%s_plot_means.png" % (NAME))

        max_diff = 0
        rgb0 = rgbs[0]
        for rgb1 in rgbs[1:]:
            rms_diff = math.sqrt(
                    sum([pow(rgb0[i] - rgb1[i], 2.0) for i in range(3)]) / 3.0)
            max_diff = max(max_diff, rms_diff)
        print "Max RMS difference:", max_diff
        msg = "Max RMS difference: %.4f, spec: %.3f" % (max_diff,
                                                        THRESHOLD_MAX_RMS_DIFF)
        assert max_diff < THRESHOLD_MAX_RMS_DIFF, msg

if __name__ == "__main__":
    main()