Exemple #1
0
 def test_matrix(self):
     original = np.array([[(255, 255, 255), (48, 113, 219), (0, 0, 0)],
                          [(0, 0, 0), (48, 113, 219), (255, 255, 255)],
                          [(48, 113, 219), (0, 0, 0), (0, 0, 0)],
                          [(255, 255, 255), (48, 113, 219),
                           (255, 255, 255)]])
     expected = np.array([[(255, 128, 128), (137, 186, 78), (0, 128, 128)],
                          [(0, 128, 128), (137, 186, 78), (255, 128, 128)],
                          [(137, 186, 78), (0, 128, 128), (0, 128, 128)],
                          [(255, 128, 128), (137, 186, 78),
                           (255, 128, 128)]])
     actual = imagetools.bgr_to_ycrcb(original)
     np.testing.assert_array_equal(
         expected, actual,
         "The original pixel- {} converted to {} and not to {} that expected"
         .format(original, actual, expected))
                               dest=os.path.join(src_dir,
                                                 mode + '_channel_c.png'))

        print('Downsampling ' + mode)
        img_channel_b = encode.upsample(encode.downsample(img_channel_b))
        img_channel_c = encode.upsample(encode.downsample(img_channel_c))

        imagetools.save_matrix(encode.concatenate_three_colors(
            img_channel_a, img_channel_b, img_channel_c),
                               mode=mode,
                               dest=os.path.join(src_dir,
                                                 mode + '_downsapling.png'))

    split_and_downsample(img, 'BGR')
    print("bgr_to_ycrcb")
    img = imagetools.bgr_to_ycrcb(img)
    split_and_downsample(img, 'YCrCb')

    def local_dct(matrix, dst, size=8):
        y, cr, cb = encode.split_to_three_colors(matrix)

        y_shape = encode.shape_for_contacting(y.shape, size)
        cb_shape = encode.shape_for_contacting(cb.shape, size)
        cr_shape = encode.shape_for_contacting(cr.shape, size)

        print("Split and padding to submatrices")
        y = [
            matrix
            for matrix in encode.split_matrix_into_sub_matrices(y, size)
        ]
        cr = [
Exemple #3
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def compress_image(src_path, dest_path, entropy=False, size=8) -> bool:
    print("Reading file")
    bitmap = imagetools.get_bitmap_from_bmp(src_path)

    if entropy:
        print("Bitmap entropy: " + str(ent.entropy(bitmap)))

    print("Crop image")
    bitmap = crop_bitmap(bitmap)

    print("Converting to YCrCb")
    bitmap = imagetools.bgr_to_ycrcb(bitmap)

    print("Separating bitmap to Y, Cb, Cr matrices")
    y, cb, cr = split_to_three_colors(bitmap)

    print("Downsampling")
    cr = downsample(cr)
    cb = downsample(cb)

    y_shape = shape_for_contacting(y.shape, size)
    cr_shape = shape_for_contacting(cr.shape, size)
    cb_shape = shape_for_contacting(cb.shape, size)

    print("Splitting to {0}x{0} sub-matrices".format(size))
    y = split_matrix_into_sub_matrices(y, size)
    cr = split_matrix_into_sub_matrices(cr, size)
    cb = split_matrix_into_sub_matrices(cb, size)

    print("dct")
    y = [dct.dct(sub_matrix) for sub_matrix in y]
    cr = [dct.dct(sub_matrix) for sub_matrix in cr]
    cb = [dct.dct(sub_matrix) for sub_matrix in cb]

    print("Quantization")
    y = [dct.quantization(submatrix) for submatrix in y]
    cr = [dct.quantization(submatrix) for submatrix in cr]
    cb = [dct.quantization(submatrix) for submatrix in cb]

    if entropy:
        print("Compressed entropy: " + str(
            ent.entropy(np.dstack([np.dstack(
                y), np.dstack(cr), np.dstack(cb)]))))

    print("UnQuantization")
    y = [dct.un_quantization(submatrix) for submatrix in y]
    cr = [dct.un_quantization(submatrix) for submatrix in cr]
    cb = [dct.un_quantization(submatrix) for submatrix in cb]

    print("Invert dct")
    y = [dct.inverse_dct(matrix) for matrix in y]
    cr = [dct.inverse_dct(matrix) for matrix in cr]
    cb = [dct.inverse_dct(matrix) for matrix in cb]

    print("Concatenate")
    y = concatenate_sub_matrices_to_big_matrix(y, y_shape)
    cr = concatenate_sub_matrices_to_big_matrix(cr, cb_shape)
    cb = concatenate_sub_matrices_to_big_matrix(cb, cr_shape)

    print("upsample")
    cr = upsample(cr)
    cb = upsample(cb)

    print("concatenate")
    concatenate_three_colors(y, cr, cb, bitmap)

    # print("ycrcb_to_bgr")
    # bitmap = imagetools.ycrcb_to_bgr(bitmap)

    print("save_matrix")
    imagetools.save_matrix(bitmap, mode='YCrCb', dest=dest_path + '.png')
Exemple #4
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def compress_image(src_path, dest_path, entropy=False,
                   size=8):  # pragma: no cover
    print("Reading file")
    bitmap = imagetools.get_bitmap_from_bmp(src_path)

    if entropy:
        print("Bitmap entropy: " + str(ent.entropy(bitmap)))

    print("Crop image")
    ycrcb_crop = crop_bitmap(bitmap)

    print("Converting to YCrCb")
    ycrcb_bitmap = imagetools.bgr_to_ycrcb(ycrcb_crop)

    print("Separating bitmap to Y, Cb, Cr matrices")
    y, cb, cr = split_to_three_colors(ycrcb_bitmap)

    print("Downsampling")
    cb_downsample = downsample(cb)
    cr_downsample = downsample(cr)

    y_shape = shape_for_contacting(y.shape, size)
    cb_shape = shape_for_contacting(cb_downsample.shape, size)
    cr_shape = shape_for_contacting(cr_downsample.shape, size)

    print("Splitting to 8x8 sub-matrices")
    y_split = split_matrix_into_sub_matrices(y)
    cb_split = split_matrix_into_sub_matrices(cb_downsample)
    cr_split = split_matrix_into_sub_matrices(cr_downsample)

    print("DCT")
    y_dct = [dct.DCT(sub_matrix) for sub_matrix in y_split]
    cb_dct = [dct.DCT(sub_matrix) for sub_matrix in cb_split]
    cr_dct = [dct.DCT(sub_matrix) for sub_matrix in cr_split]

    print("Quantization")
    y_quantization = [dct.quantization(submatrix) for submatrix in y_dct]
    cb_quantization = [dct.quantization(submatrix) for submatrix in cb_dct]
    cr_quantization = [dct.quantization(submatrix) for submatrix in cr_dct]

    if entropy:
        print("Compressed entropy: " + str(
            ent.entropy(
                np.array([y_quantization, cb_quantization, cr_quantization]))))

    print("UnQuantization")
    y_un_quantization = [
        dct.un_quantization(submatrix) for submatrix in y_quantization
    ]
    cb_un_quantization = [
        dct.un_quantization(submatrix) for submatrix in cb_quantization
    ]
    cr_un_quantization = [
        dct.un_quantization(submatrix) for submatrix in cr_quantization
    ]

    print("Invert DCT")
    y_invert_dct = [dct.inverse_DCT(matrix) for matrix in y_un_quantization]
    cb_invert_dct = [dct.inverse_DCT(matrix) for matrix in cb_un_quantization]
    cr_invert_dct = [dct.inverse_DCT(matrix) for matrix in cr_un_quantization]

    print("Concatenate")
    y_big = concatenate_sub_matrices_to_big_matrix(y_invert_dct, y_shape)
    cb_big = concatenate_sub_matrices_to_big_matrix(cb_invert_dct, cb_shape)
    cr_big = concatenate_sub_matrices_to_big_matrix(cr_invert_dct, cr_shape)

    print("upsample")
    cb_upsample = upsample(cb_big)
    cr_upsample = upsample(cr_big)

    new_image = concatenate_three_colors(y_big, cb_upsample, cr_upsample)

    imagetools.save_matrix(new_image, mode='YCrCb', dest=dest_path + '.png')
Exemple #5
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 def test_vs_cv2(self):
     im = cv2.imread(os.path.join(src, "colored.bmp"))
     expected = cv2.cvtColor(im, cv2.COLOR_BGR2YCrCb)
     actual = imagetools.bgr_to_ycrcb(im)
     different = np.count_nonzero(actual - expected) / np.prod(im.shape)
     self.assertLessEqual(different, 1 / 100)