def main():
parser = argparse.ArgumentParser()
parser.add_argument("-dd",
"--data-dir",
type=str,
default=os.environ.get("KAGGLE_2020_ALASKA2"))
args = parser.parse_args()
data_dir = args.data_dir
cover = fs.find_images_in_dir(os.path.join(data_dir, "Cover"))
jimi = fs.find_images_in_dir(os.path.join(data_dir, "JMiPOD"))
juni = fs.find_images_in_dir(os.path.join(data_dir, "JUNIWARD"))
uerd = fs.find_images_in_dir(os.path.join(data_dir, "UERD"))
for cover_fname, jimi_fname, juni_fname, uerd_fname in zip(
tqdm(cover), jimi, juni, uerd):
cover = decode_bgr_from_dct(fs.change_extension(cover_fname, ".npz"))
jimi = decode_bgr_from_dct(fs.change_extension(jimi_fname, ".npz"))
juni = decode_bgr_from_dct(fs.change_extension(juni_fname, ".npz"))
uerd = decode_bgr_from_dct(fs.change_extension(uerd_fname, ".npz"))
jimi_mask = block8_sum(np.abs(cover - jimi).sum(axis=2)) > 0
juni_mask = block8_sum(np.abs(cover - juni).sum(axis=2)) > 0
uerd_mask = block8_sum(np.abs(cover - uerd).sum(axis=2)) > 0
cover_mask = jimi_mask | juni_mask | uerd_mask
cv2.imwrite(fs.change_extension(cover_fname, ".png"), cover_mask * 255)
cv2.imwrite(fs.change_extension(jimi_fname, ".png"), jimi_mask * 255)
cv2.imwrite(fs.change_extension(juni_fname, ".png"), juni_mask * 255)
cv2.imwrite(fs.change_extension(uerd_fname, ".png"), uerd_mask * 255)
def test_decoding_residual():
# d:\datasets\ALASKA2\Cover\20805.jpg
# d:\datasets\ALASKA2\UERD\20805.jpg
# /home/bloodaxe/datasets/ALASKA2/Cover/18051.jpg
# /home/bloodaxe/datasets/ALASKA2/UERD/18051.jpg
# cover = cv2.imread("d:/datasets/ALASKA2/Cover/38330.jpg")
# stego = cv2.imread("d:/datasets/ALASKA2/UERD/38330.jpg")
# r1 = compute_decoding_residual(cover, "d:/datasets/ALASKA2/Cover/38330.npz")
# r2 = compute_decoding_residual(stego, "d:/datasets/ALASKA2/UERD/38330.npz")
cover = 255 * decode_bgr_from_dct(
"d:/datasets/ALASKA2/Cover/50846.npz"
) # cv2.imread("d:/datasets/ALASKA2/Cover/50846.jpg")
cover_cv2 = cv2.imread("d:/datasets/ALASKA2/Cover/50846.jpg")
cv2.imwrite("cover_read_with_cv2.png", cover_cv2)
cv2.imwrite("cover_from_dct.png", cover.astype(np.uint8))
stego = 255 * decode_bgr_from_dct("d:/datasets/ALASKA2/JMiPOD/50846.npz")
print(cover.max(), cover.min())
cv2.imshow("Cover", cover.astype(np.uint8))
cv2.imshow("Stego", stego.astype(np.uint8))
cv2.waitKey(-1)
def test_dct_comp():
methods = ["Cover", "JMiPOD", "JUNIWARD", "UERD"]
cover_diff = None
f, ax = plt.subplots(4, 4, figsize=(8 * 4, 8 * 4))
for i, method in enumerate(methods):
bgr = cv2.imread(os.path.join(TEST_DATA_DIR, method, "00001.jpg"))
bgr_from_dct = decode_bgr_from_dct(
os.path.join(TEST_DATA_DIR, method, "00001.npz"))
bgr_from_dct_byte = (bgr_from_dct * 255).astype(np.uint8)
if i == 0:
cover_diff = cv2.absdiff(bgr_from_dct * 255,
bgr.astype(np.float32)).sum(axis=2)
decode_diff = cv2.absdiff(bgr_from_dct * 255,
bgr.astype(np.float32)).sum(axis=2)
print(decode_diff.mean(), decode_diff.std())
ax[i, 0].imshow(bgr)
ax[i, 0].axis("off")
ax[i, 1].imshow(bgr_from_dct_byte)
ax[i, 1].axis("off")
ax[i, 2].imshow(decode_diff, cmap="gray")
ax[i, 2].axis("off")
ax[i, 3].imshow(cv2.absdiff(decode_diff, cover_diff), cmap="gray")
ax[i, 3].axis("off")
plt.show()
def compute_features_proc(image_fname):
dct_file = fs.change_extension(image_fname, ".npz")
image = 2 * (decode_bgr_from_dct(dct_file) / 140 - 0.5)
entropy_per_channel = [
entropy(image[..., 0].flatten()),
entropy(image[..., 1].flatten()),
entropy(image[..., 2].flatten()),
]
f = [
image[..., 0].mean(),
image[..., 1].mean(),
image[..., 2].mean(),
image[..., 0].std(),
image[..., 1].std(),
image[..., 2].std(),
entropy_per_channel[0],
entropy_per_channel[1],
entropy_per_channel[2],
]
return f
def read_from_dct(image_fname):
return decode_bgr_from_dct(fs.change_extension(image_fname, ".npz"))