decrypt jpeg image
from struct import unpack
marker_mapping = {
0xffd8: "Start of Image",
0xffe0: "Application Default Header",
0xffdb: "Quantization Table",
0xffc0: "Start of Frame",
0xffc4: "Define Huffman Table",
0xffda: "Start of Scan",
0xffd9: "End of Image"
}
class JPEG:
def __init__(self, image_file):
with open(image_file, 'rb') as f:
self.img_data = f.read()
def decode(self):
data = self.img_data
while(True):
marker, = unpack(">H", data[0:2])
print(marker_mapping.get(marker))
if marker == 0xffd8:
data = data[2:]
elif marker == 0xffd9:
return
elif marker == 0xffda:
data = data[-2:]
else:
lenchunk, = unpack(">H", data[2:4])
data = data[2+lenchunk:]
if len(data)==0:
break
if __name__ == "__main__":
img = JPEG('profile.jpg')
img.decode()
# OUTPUT:
# Start of Image
# Application Default Header
# Quantization Table
# Quantization Table
# Start of Frame
# Huffman Table
# Huffman Table
# Huffman Table
# Huffman Table
# Start of Scan
# End of Image