def embed_specific(self, image, image_file, watermark=None):
i_width = image.shape[0]
i_height = image.shape[1]
wm = watermark
wm_width = wm.shape[0]
wm_height = wm.shape[1]
if not (wm_width == i_width / 2 and wm_height == i_height / 2):
raise WmError("Watermark size must be half of image size. For now.")
ir, ig, ib = self.split_image(image)
img = self.split_image(wm)
dcts_wm = self.rgb_to_dct(*img)
dwts_i = self.rgb_to_dwt(ir, ig, ib)
for color in range(3):
dct = dcts_wm[color]
hh = TwoDimensionalDCT.forward(dwts_i[color][1][2])
for j in range(len(dct)):
for k in range(len(dct[0])):
hh[j][k] += dct[j][k] * self.alpha
ihh = TwoDimensionalDCT.inverse(hh)
hh = dwts_i[color][1][2]
for j in range(len(dct)):
for k in range(len(dct[0])):
hh[j][k] = ihh[j][k]
rgb = self.dwt_to_rgb(*dwts_i)
img = self.join_image(*rgb)
return img
def embed_specific(self, image, image_file, watermark=None):
# Compute DCT
f_dct = TwoDimensionalDCT.forward(image)
# Sort DCT
size_dct = int(f_dct.__len__()*self.watermark_size_percentage)
sorted_dct_indexes = f_dct.ravel().argsort()[-size_dct:]
sorted_dct_indexes = (numpy.unravel_index(indx, f_dct.shape) for indx in sorted_dct_indexes)
sorted_unraveled = [(f_dct[indx], indx) for indx in sorted_dct_indexes]
nbits = numpy.random.normal(self.mu, self.sigma, size_dct)
# Construct the Watermark
for i in range(len(nbits)):
f_dct[sorted_unraveled[i][1]] += self.alpha * nbits[i]
self.export_image(sorted_unraveled, image_file, nbits)
inverse = TwoDimensionalDCT.inverse(f_dct)
return inverse
def test_idct_close_values(self):
img = TwoDimensionalDCT.inverse(TwoDimensionalDCT.forward(self.close_values))
self._test_inverse(img, self.close_values)
def dct_to_rgb(self, cr, cg, cb):
return TwoDimensionalDCT.inverse(cr), TwoDimensionalDCT.inverse(cg), TwoDimensionalDCT.inverse(cb)
def test_idct_solid_gray(self):
img = TwoDimensionalDCT.inverse(TwoDimensionalDCT.forward(self.solid_gray))
self._test_inverse(img, self.solid_gray)
