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Old 20th February 2019, 00:51   #21  |  Link
StainlessS
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Quote:
Lossy compression will not be kind to the noisy data you'll be trying to transmit. Is there a reason you can't just send an encrypted zip file containing the whole video file?
We are (me is) currently in experimental stage, perhaps we could do some denoising on random key clip before encrypting/decryption (DCTFilter I think is intended for something like that),
also probably need use of Limiter() plug at some point (on both key and Target clip).
Maybe I got it wrong on needing single bit shift, I'm not sure but suspect that may require a Left shift of 7, rather than a left shift of 1 (so that most significant bit of 8 bit clip is in bit 14,
with bit 15=0. Might also need random bits set in 15 and bit 6, to encourage x264 to think it is detail and not to screw with it.


I'm kinda interested to see if we can get this working, although zip with password would be a helluva lot easier.

EDIT: Currently, have tried encrypt/encode from original JohnMeyer Parade mp4 (~22.5MB) to 10 bit x264 CRF 18 Preset=Slower, and result
was a whopping 980MB, so a wee bit bigger than original source. This was kinda expected, we will be wanting to experiment with some kind
of multi blurring on the random key, will still obfuscate encrypted clip nicely, but with (hopefully) better compression.
Might even try pixelating the random clip, with additional blurring, lots to try out.
We are gonna hav'ta 'suck-it-and-see' what happens.
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"Some infinities are bigger than other infinities", but how many of them are infinitely bigger ???

Last edited by StainlessS; 20th February 2019 at 17:24.
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Old 27th February 2019, 20:44   #22  |  Link
spoRv
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Tried using a compressed version for the difference clip (h264 and h265), and result is not good... hence, the only way to go is lossless, even if it means A HUGE file!
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Old 3rd March 2019, 15:36   #23  |  Link
StainlessS
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Quote:
Tried using a compressed version for the difference clip (h264 and h265), and result is not good
Yeh not good, think maybe some of problem down to illegal TV range colors being created via the XOR-ing, [eg fully saturated chroma when BLACK] below demos it
(I modded the KEY clip genny to be a bit smoother, still no joy at all).

Code:
Function EncryptPrep(clip c) { Return c.ConvertToYV12.Limiter(min_luma=16,  max_luma=235,  min_chroma=16, max_chroma=240 ) }

Function GenRandomKey(clip c,int Seed,Int "Rad",int "Y_Lim",Int "UV_Lim") {
	Rad=Default(Rad,4)              Y_Lim=Default(Y_Lim,20)       UV_Lim=Default(UV_Lim,20)
	W=round(c.Width/(Rad*4))*4	H=round(c.Height/(Rad*4))*4
        RandomSource(Length=c.FrameCount,Width=W,Height=H,Seed=Seed)
	BicubicResize(c.Width,c.Height,1,0)
	ConvertToYV12
   	Limiter(min_luma=16+Y_Lim,  max_luma=235-Y_Lim,  min_chroma=16+UV_Lim, max_chroma=240-UV_Lim )
	return Last
}

SECRET_KEY = 123456789

AviSource("D:\Parade.avi").Trim(1000,-2000).EncryptPrep()
#Return Last

RAD=4
LIM=20
KEY       = GenRandomKey(SECRET_KEY,Rad=RAD,Y_Lim=LIM,UV_Lim=LIM)
#Return KEY

ENCRYPTED = MT_Logic(KEY,"xor",y=3,u=3,v=3)                 # Encrypt
Return ENCRYPTED

# Result of Encypted.Limiter.Decrypt suggests part problem is Illegal YUV colors created by Encryption.
#Return ENCRYPTED.Limiter.MT_Logic(KEY,"xor",y=3,u=3,v=3)

return ENCRYPTED.MT_Logic(KEY,"xor",y=3,u=3,v=3)            # Decrypt
Key frame (random)


Single frame after encrypt


Encypted.Limiter.Decrypt


Encypted..Decrypt, same as original


EDIT: Actually, the UT_Video compressed Encrypted clip is smaller than the original UT_Video encoded clip
(422MB instead of 432MB, but that might be down to using Limiter on the original clip before encrypting).

EDIT: Changing RAD to 16 produces a rather fancy effect random KEY frame.


and then encrypted
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"Some infinities are bigger than other infinities", but how many of them are infinitely bigger ???

Last edited by StainlessS; 3rd March 2019 at 16:06.
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Old 13th March 2019, 03:10   #24  |  Link
spoRv
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Code:
function deconstruct(clip original, clip modified, Int "Seed" , Int "blk") {
# needs scramble/descramble: https://forum.doom9.org/showthread.php?p=1868405#post1868405
modified
coloryuv(levels="TV->PC")
MT_Logic(original,"xor",y=3,u=3,v=3)
scramble(seed=seed,blk=blk)
}

function reconstruct(clip original, clip deconstructed, Int "Seed" , Int "blk") {
# needs scramble/descramble: https://forum.doom9.org/showthread.php?p=1868405#post1868405
deconstructed
descramble(seed=seed,blk=blk)
MT_Logic(original,"xor",y=3,u=3,v=3)
coloryuv(levels="PC->TV")
}


WARNING: deconstructed video MUST be lossless/uncompressed; its size could be 50/60% bigger than original clip (using the same compression)

Thanks to StainlessS for his help!
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