kira924age/SECCON_WARS_2015.md

## SECCON_WARS_2015.md

      
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              SECCON_WARS_2015.md
            
          
First, download a mp4 file from youtube (https://www.youtube.com/watch?v=8SFsln4VyEk).


Second, convert mp4 to gif by using Free Video to GIF Converter.


When I converted mp4 to gif, I cutted from 00:25 to 01:05 in the movie.
Size of gif is widh:600, weigh:437, and frame rate is 2 frames per seccond.

Finally, run wars_solver_ver2.py, and scan flag.png as a QR code.


## wars_solver_ver2.py
#!/usr/bin/env python
#-*- coding: utf-8 -*-

from PIL import Image

gif = Image.open('hoge.gif')

width, height = gif.size
png = Image.new('RGB', gif.size, 'black')

while True:
    gif.load()
    for pos in ((x, y) for x in range(width) for y in range(height)):
        if gif.getpixel(pos) < 0x80:
            png.putpixel(pos, (0xff, 0xff, 0xff))

    try:
        gif.seek(gif.tell() + 1)
    except:
        break

png.save('flag.png', 'PNG')
	#!/usr/bin/env python
	#-- coding: utf-8 --

	from PIL import Image

	gif = Image.open('hoge.gif')

	width, height = gif.size
	png = Image.new('RGB', gif.size, 'black')

	while True:
	gif.load()
	for pos in ((x, y) for x in range(width) for y in range(height)):
	if gif.getpixel(pos) < 0x80:
	png.putpixel(pos, (0xff, 0xff, 0xff))

	try:
	gif.seek(gif.tell() + 1)
	except:
	break

	png.save('flag.png', 'PNG')