2017年12月9-10日に開催されたseccon 2017 online Qubic Rubeのwrite upです。
アルゴリズムの説明
- QRコード(6枚すべて)をスクレイピングでとってくる
- 各画像を9分割して、背景色ごとに種類分けする
- 背景色ごとに種類分けした画像をポジションごとに種類分けする(角,端,真ん中)
- (角,端,真ん中)の特定は、上下左右に黒色がないかで特定できる
- 角,端,真ん中が判ればQRコードのパターンは
4*4!*4!/4 = 576なので総当たりで殴る!!
計算の合計は 50*6*576 = 172800 で1時間半ぐらいで走り切る
環境構築メモ
- Python 3.6.3
python -m pip install pyzbar python -m pip install pillow python -m pip install opencv-python python -m pip install scipy
プログラム
#!/bin/python
from pyzbar.pyzbar import decode
from PIL import Image
from scipy import ndimage
import urllib.request
import cv2
import itertools
import re
fastHash = '01000000000000000000'
bgr = {
'yellow' : [0, 213, 255],
'blue' : [186, 81, 0],
'green' : [96, 158, 0],
'white' : [255, 255, 255],
'red' : [58, 30, 196],
'orange' : [0, 88, 255],
'black' : [0, 0, 0],
}
def main():
hash = fastHash
#50回回す
for count in range(1,51):
# for count in range(1,3):
print(str(count) + '/50')
bg_color = {
'yellow' : [],
'blue' : [],
'green' : [],
'white' : [],
'red' : [],
'orange' : [],
}
scrap(count, hash)
hash = None # clear
for txt in ['U','D','L','R','F','B']:
fileName = str(count) + '_' + txt + '.png'
input_image = cv2.imread(fileName)
# cv2.imwrite(tmp_image_name, toBinarization(img))
# 画像を9等分
for i in cutNine(input_image):
c = getBackColor(i)
# 背景別に種類分けリストに追加
if c == bgr['yellow']:
bg_color['yellow'].append(i)
elif c == bgr['blue']:
bg_color['blue'].append(i)
elif c == bgr['green']:
bg_color['green'].append(i)
elif c == bgr['white']:
bg_color['white'].append(i)
elif c == bgr['red']:
bg_color['red'].append(i)
elif c == bgr['orange']:
bg_color['orange'].append(i)
# 各色ごとにQRを完成させる
for color, qr_img in bg_color.items():
break_flag = False
# 画像をジャンル分け
qr_parts_corner = []
qr_parts_side = []
qr_parts_center = []
for m_img in qr_img:
coordinateType = getCoordinateType(m_img)
if coordinateType == 'corner':
qr_parts_corner.append(m_img)
elif coordinateType == 'side':
qr_parts_side.append(m_img)
else:
qr_parts_center.append(m_img)
# 4!*4!回画像を組み立てる
for qr_pattern_corner in list(itertools.permutations( range(4) )):
for qr_pattern_side in list(itertools.permutations( range(4) )):
topImg = cv2.hconcat( [changeTiltUpperLeft(qr_parts_corner[qr_pattern_corner[0]]),
changeTiltTop( qr_parts_side[qr_pattern_side[0]]),
changeTiltUpperRight (qr_parts_corner[qr_pattern_corner[2]]) ] )
centerImg = cv2.hconcat( [changeTiltLeft(qr_parts_side[qr_pattern_side[1] ]),
qr_parts_center[0],
changeTiltRight (qr_parts_side[qr_pattern_side[2]]) ])
bottomImg = cv2.hconcat( [changeTiltBottomLeft(qr_parts_corner[qr_pattern_corner[1]]),
changeTiltBottom( qr_parts_side[qr_pattern_side[3]]),
changeTiltBottomRight (qr_parts_corner[qr_pattern_corner[3]]) ] )
qr_image = cv2.vconcat([topImg, centerImg, bottomImg])
# 背景色を白にして画像を保存
cv2.imwrite('qr_image.png', toBinarization(qr_image))
# QRコードを読み取り 失敗したら次のパターンを試す
try:
data = decode(Image.open('qr_image.png'))
text = data[0][0].decode('utf-8', 'ignore')
print('[-] ' + color + ' : ' + text)
break_flag = True
if re.match(r"^http" , text):
hash = text.split('/')[-1]
except IndexError:
pass
if break_flag:
break
if break_flag:
break
# スクレイピング
def scrap(count, hash):
for txt in ['U','D','L','R','F','B']:
url = 'http://qubicrube.pwn.seccon.jp:33654/images/' + hash + '_' + txt + '.png'
fileName = str(count) + '_' + txt + '.png'
urllib.request.urlretrieve(url, fileName)
# 9等分
def cutNine(img):
height, width = img.shape[:2]
m_height = int(height/3)
m_width = int(width/3)
dst1 = img[0 * m_height:1 * m_height, 0 * m_width:1 * m_width]
dst2 = img[0 * m_height:1 * m_height, 1 * m_width:2 * m_width]
dst3 = img[0 * m_height:1 * m_height, 2 * m_width:3 * m_width]
dst4 = img[1 * m_height:2 * m_height, 0 * m_width:1 * m_width]
dst5 = img[1 * m_height:2 * m_height, 1 * m_width:2 * m_width]
dst6 = img[1 * m_height:2 * m_height, 2 * m_width:3 * m_width]
dst7 = img[2 * m_height:3 * m_height, 0 * m_width:1 * m_width]
dst8 = img[2 * m_height:3 * m_height, 1 * m_width:2 * m_width]
dst9 = img[2 * m_height:3 * m_height, 2 * m_width:3 * m_width]
return [dst1, dst2, dst3, dst4, dst5, dst6, dst7, dst8, dst9]
# 背景を全部白色に。
def toBinarization(img):
height, width = img.shape[:2]
for i in range(height):
for j in range(width):
blue = img.item(i, j, 0)
green = img.item(i, j, 1)
red = img.item(i, j, 2)
if blue != 0 or green != 0 or red != 0:
img[i, j] = [255, 255, 255]
return img
# 背景色を返す
def getBackColor(img):
height, width = img.shape[:2]
for i in range(height):
for j in range(width):
blue = img.item(i, j, 0)
green = img.item(i, j, 1)
red = img.item(i, j, 2)
# if 0 not in [blue, green, red]:
if blue != 0 or green != 0 or red != 0:
return [blue, green, red]
return 0,0,0
"""
+---+---+---+
| 1 | 2 | 3 |
+---+---+---+
| 4 | 5 | 6 |
+---+---+---+
| 7 | 8 | 9 |
+---+---+---+
"""
def getCoordinateId(img):
height, width = img.shape[:2]
cutLevel = 6
imgTop = img[0:int(height/cutLevel), 0:width]
imgBottom = img[(cutLevel - 1)*int(height/cutLevel):height, 0:width]
imgLeft = img[0:height, 0:int(width/cutLevel)]
imgRight = img[0:height, (cutLevel - 1)*int(width/cutLevel):width]
is_Top = chackAllColor(imgTop)
is_Bottom = chackAllColor(imgBottom)
is_Left = chackAllColor(imgLeft)
is_Right = chackAllColor(imgRight)
if is_Top and is_Left:
return 1
elif is_Bottom and is_Left:
return 9
elif is_Top and is_Right:
return 3
elif is_Bottom and is_Right:
return 7
elif is_Top:
return 2
elif is_Bottom:
return 8
elif is_Left:
return 4
elif is_Right:
return 6
else:
return 5
def getCoordinateType(img):
coordinateId = getCoordinateId(img)
if coordinateId in [1, 3, 7, 9]:
return 'corner'
elif coordinateId in [2, 4, 6, 8]:
return 'side'
else:
return 'center'
def chackAllColor(img):
height, width = img.shape[:2]
for i in range(height):
for j in range(width):
blue = img.item(i, j, 0)
green = img.item(i, j, 1)
red = img.item(i, j, 2)
if [blue, green, red] == bgr['black']:
return False
return True
def tilt90(img):
img = ndimage.rotate(img, 90, reshape=False)
return img
# 画像の向きを変える
def changeTiltUpperLeft(img):
while getCoordinateId(img) != 1:
img = tilt90(img)
return img
def changeTiltBottomRight(img):
while getCoordinateId(img) != 7:
img = tilt90(img)
return img
def changeTiltUpperRight(img):
while getCoordinateId(img) != 3:
img = tilt90(img)
return img
def changeTiltBottomLeft(img):
while getCoordinateId(img) != 9:
img = tilt90(img)
return img
def changeTiltTop(img):
while getCoordinateId(img) != 2:
img = tilt90(img)
return img
def changeTiltBottom(img):
while getCoordinateId(img) != 8:
img = tilt90(img)
return img
def changeTiltLeft(img):
while getCoordinateId(img) != 4:
img = tilt90(img)
return img
def changeTiltRight(img):
while getCoordinateId(img) != 6:
img = tilt90(img)
return img
if __name__ == '__main__':
main()
感想
チームメンバが先に解いてくれたので、意味がなかった。