The robots appear to be testing some kind of new camera technology but we haven't quite figured it out yet. Understanding this imaging could be crucial to our understanding the enemy and winning the war. http://ctf.plaidctf.com/media/files/3d-4e5132069964e0d61c0fbd9099dea498/edbd4701d0b9d2a33a743e96f7bc8f3b
We quickly downloaded the image file and opened it up in our favorite image viewer (Preview -- because I can just hit spacebar! :). The image looks like a computer screen showing gedit open with the key typed in. However, a piece of paper is held in the way. Since the challenge is called 3D, we expected the file to be stereoscopic. We quickly try to open it on a 3D capable Android phone, no luck. It was the wrong format.
Well, what's the first thing we do with an image? We run it through exiftool!
~/ctf/pct/3d/ $ exiftool edbd4701d0b9d2a33a743e96f7bc8f3b ExifTool Version Number : 8.59 File Name : edbd4701d0b9d2a33a743e96f7bc8f3b Directory : . File Size : 6.0 MB File Modification Date/Time : 2012:04:27 07:32:14-04:00 File Permissions : rw-r--r-- File Type : JPEG MIME Type : image/jpeg Exif Byte Order : Little-endian (Intel, II) Image Description : Make : SONY Camera Model Name : DSC-HX9V Orientation : Horizontal (normal) X Resolution : 72 Y Resolution : 72 Resolution Unit : inches Modify Date : 2012:04:04 11:32:05 Y Cb Cr Positioning : Co-sited Exposure Time : 1/125 F Number : 3.3 Exposure Program : Program AE ISO : 200 Sensitivity Type : Recommended Exposure Index Recommended Exposure Index : 200 Exif Version : 0230 Date/Time Original : 2012:04:04 11:32:05 Create Date : 2012:04:04 11:32:05 Components Configuration : Y, Cb, Cr, - Compressed Bits Per Pixel : 1 Brightness Value : 4.3609375 Exposure Compensation : 0 Max Aperture Value : 3.3 Metering Mode : Multi-segment Light Source : Unknown Flash : Off, Did not fire Focal Length : 4.3 mm Panorama Full Width : 1920 Panorama Full Height : 1080 Panorama Direction : Left to Right Panorama Crop Left : 0 Panorama Crop Top : 0 Panorama Crop Right : 1920 Panorama Crop Bottom : 1080 Panorama Frame Width : 1920 Panorama Frame Height : 1080 Panorama Source Width : 1784 Panorama Source Height : 1004 Brightness : 0 High ISO Noise Reduction : n/a HDR : Off Face Info Offset : 94 Sony Date Time : 2012:04:04 11:32:05 Faces Detected : 0 Face Info Length : 37 Color Reproduction : Standard Scene Mode : n/a Zone Matching : ISO Setting Used Image Stabilization : Unknown (4294967295) Macro : Off Focus Mode : Permanent-AF AF Mode : Default AF Illuminator : Off Quality : Fine Flash Level : Unknown (128) Release Mode : Normal Sequence Number : Single Long Exposure Noise Reduction : Unknown (2) Dynamic Range Optimizer : Off Intelligent Auto : Off White Balance : Auto User Comment : Flashpix Version : 0100 Color Space : sRGB Exif Image Width : 1920 Exif Image Height : 1080 Interoperability Index : R98 - DCF basic file (sRGB) Interoperability Version : 0100 File Source : Digital Camera Scene Type : Directly photographed Custom Rendered : Normal Exposure Mode : Auto Scene Capture Type : Standard Contrast : Normal Saturation : Normal Sharpness : Normal Lens Info : 4.28-68.48mm f/3.3-5.9 GPS Version ID : 2.3.0.0 GPS Status : Measurement Void GPS Img Direction Ref : Magnetic North GPS Img Direction : 81 GPS Map Datum : WGS-84 GPS Differential : No Correction PrintIM Version : 0300 Compression : JPEG (old-style) Thumbnail Offset : 13618 Thumbnail Length : 5020 Number Of Images : 15 MP Image Flags : (none) MP Image Format : JPEG MP Image Type : Multi-frame Disparity MP Image Length : 373993 MP Image Start : 5960192 Dependent Image 1 Entry Number : 0 Dependent Image 2 Entry Number : 0 Total Frames : 15 MPF Version : 0100 MP Individual Num : 1 Base Viewpoint Num : 8 Convergence Angle : 1 Baseline Length : 1 Image Width : 1920 Image Height : 1080 Encoding Process : Baseline DCT, Huffman coding Bits Per Sample : 8 Color Components : 3 Y Cb Cr Sub Sampling : YCbCr4:2:2 (2 1) Aperture : 3.3 Image Size : 1920x1080 MP Image 2 : (Binary data 381309 bytes, use -b option to extract) MP Image 3 : (Binary data 376878 bytes, use -b option to extract) MP Image 4 : (Binary data 374914 bytes, use -b option to extract) MP Image 5 : (Binary data 374557 bytes, use -b option to extract) MP Image 6 : (Binary data 374987 bytes, use -b option to extract) MP Image 7 : (Binary data 375239 bytes, use -b option to extract) MP Image 8 : (Binary data 376199 bytes, use -b option to extract) MP Image 9 : (Binary data 377134 bytes, use -b option to extract) MP Image 10 : (Binary data 378356 bytes, use -b option to extract) MP Image 11 : (Binary data 379828 bytes, use -b option to extract) MP Image 12 : (Binary data 378485 bytes, use -b option to extract) MP Image 13 : (Binary data 377924 bytes, use -b option to extract) MP Image 14 : (Binary data 374779 bytes, use -b option to extract) MP Image 15 : (Binary data 373993 bytes, use -b option to extract) Shutter Speed : 1/125 Thumbnail Image : (Binary data 5020 bytes, use -b option to extract) Focal Length : 4.3 mm Light Value : 9.4
Exiftool suggests it has 15 additional images, using -b just prints them all to the screen. Joy -- now I have to reset my terminal.
Next, we opened it in 010 and applied the JPEG template. It looked to be 10+ JPEGs concatenated together. Let's split them on the JPEG start record bytes and write them out.
#!/usr/bin/env python
import os
import sys
contents = open("edbd4701d0b9d2a33a743e96f7bc8f3b", "rb").read()
images = contents.split("\xff\xd8\xff\xe1")
print len(images)
im = 1
for i in images:
open(str(im) + ".jpg", "wb").write("\xff\xd8\xff\xe1" + i)
im +=1
3d_g1v35_m3_a_h3adach3
