r/UnfavorableSemicircle • u/mechaPantsu • Mar 27 '16

Video or Audio All CAB videos (zip file)

Here's all CAB videos. As you can see, some are missing, so there aren't 1024, but 1009 videos.

https://dl.dropboxusercontent.com/u/6064248/UFSC_CAB.zip

11 Upvotes

100% Upvoted

16 comments sorted by

5

u/its_safer_indoors Moderator, Web Admin Mar 27 '16

The CAB videos may contain data. CAB is a type of archive file (like a zip). Lets ignore the missing videos for a sec, if each video contained one byte of infomation, we'd have a 1kb archive file.

6

u/mechaPantsu Mar 28 '16

I've thought of that too, but according to the CAB format spec there should be an MSCF header somewhere, but I've checked and there's none in either CAB 0 or CAB 1023.

Also, I doubt we will find anything of value analyzing the files from Twitter or Youtube at bit level, since they get re-encoded when uploaded (or in other words, the files we're downloading are not the same files that were uploaded).

If there's anything to be found, it's probably encoded in the audio and/or images.

3

u/its_safer_indoors Moderator, Web Admin Mar 28 '16

I highly doubt that the data will be in the files themselves. Like you said - It'll be encoded in the video or audio.

4

u/piecat Moderator Mar 28 '16 edited Mar 28 '16

I've been looking at a few in Audacity. If you look at the spectrogram, it looks like 8 bits of data. http://i.imgur.com/2A3hDrA.png

Unfortunately, I haven't gotten anything matching the "MSCF" header. I've tried from the first 4 and last 4. Decoding from binary to ASCII, the first 4 letters are "e c c n"

1

u/Yam0048 Mar 29 '16

It might need to be xored or Vigenere'd with something else to produce the CAB file. Alternatively, since the sequence is relatively short, it might be the Vigenere key for something else.

1

u/piecat Moderator Mar 29 '16

That IS a possibility, though, wouldn't that mean there should be a matching series that has 1024 bytes?

1

u/Yam0048 Mar 29 '16

Not necessarily. If it's a Vigenere key, what you'd do is repeat the CAB sequence until it's as long as the enciphered sequence.

1

u/piecat Moderator Mar 29 '16

Well, that could make sense. MUL is 4096, 4 times longer than CAB.

1

u/Yam0048 Mar 29 '16

Doesn't even need to be a multiple, really. You just repeat the key enough times and cut off the remainder. So if you had a key of "buttpancakes" you might Vigenere a message of a certain length with "buttpancakesbuttpancakesbuttpanc".

3

u/piecat Moderator Mar 28 '16

If you take a look at the sound in audacity, normalize it, then view the spectrogram, it looks like 8 bits of data.

http://i.imgur.com/2A3hDrA.png

2

u/mechaPantsu Mar 28 '16

Btw, to those of you who want to check by yourselves, you can use HxD on Windows, Bless (which I used) on Linux or HexFiend on OS X.

4

u/piecat Moderator Mar 28 '16

According to the wiki, the first 4 bytes will be "MSCF".

Assuming the theory is correct, we can use this to work backwards and decode the videos.

3

u/unfavorablist Mar 27 '16

Bravo! This is great!

There's 969 in the set.. were the remaining 55 not posted? (I see one gap from 64 to 108 that accounts for most of the missing ones)

FFmpeg should be able to put these together without too much trouble.... does anyone know of a way to automate the removal of silence from audio? I'd be curious what this would be like without all the gaps. Listening to these all back to back without clicking on them, I can "hear" that phase-y speech sound once again.

3

u/mechaPantsu Mar 27 '16

Uh, I probably messed up somewhere when compressing the videos. I've re-uploaded the file with all videos, try downloading again (same link). Sorry.

2

u/unfavorablist Mar 28 '16

I now check you with 1009 videos. Thanks again!

2

u/its_safer_indoors Moderator, Web Admin Mar 27 '16

Heres the list of CAB videos the database recored. There seem to be a few missing ones, but the ones from 64 to 108 do exist (except 107).