Rating:
## Satan's Jigsaw
This was the challenge text:
```
Satan's Jigsaw - 736 Points
Oh no! I dropped my pixels on the floor and they're all muddled up! It's going to take me years to sort all 90,000 of these again :(
Dev: Tom
Hint! long_to_bytes
chall.7z
```
I first extracted the pictures, there are indeed 90,000 of them!
```
$ 7z x chall.7z
...
$ find chall/ -type f | wc -l
90000
```
Each jpg is a 1x1 pixel:
```
$ mediainfo chall/54082768285744.jpg
General
Complete name : chall/54082768285744.jpg
Format : JPEG
File size : 631 Bytes
Image
Format : JPEG
Width : 1 pixel
Height : 1 pixel
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Compression mode : Lossy
Stream size : 631 Bytes (100%)
```
I decided to use Python with PIL to write the pixels to an image by ordering them by their file name number. I took a first guess that perhaps the dimensions of the picture were (300x300 = 90,000):
```python
import os
from PIL import Image
files = sorted(os.listdir('chall/'))
final_image = Image.new('RGB', (300, 300))
i = 0
pixels = []
for f in files:
im = Image.open('chall/' + f)
pixel = im.load()[0, 0]
pixels.append(pixel)
i += 1
final_image.putdata(pixels)
final_image.save('test.png')
```
The result:
The dimensions I guessed are off, but we can make out a QR code to scan.
It gives us the flag: `rtcp{d1d-you_d0_7his_by_h4nd?}`
