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YouTubeDrive: Store files as YouTube videos

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Re: YouTubeDrive: Store files as YouTube videos

#251
post #227

Earlier quoted context omitted.

That's the thing though, "looks like" breaks down pretty quickly with things that aren't real images. It even breaks down pretty quickly with things that are real, but maybe not so common, images: https://www.youtube.com/watch?v=r6Rp-uo6HmI So one question would be: Does your image generation approach preserve a higher information density than big enough pixels?

Why would you assume that the images in my algorithm aren't real images? For example, you could use 256 categories from imagenet as your keys. Image of a dog is 00000000, tree is 00000001, car 00000010, and so on.

I'm not assuming they are not real images, I'm questioning whether to get to any information density that even out-performs "big enough colorful pixels", you might get into territories where the lossy compression compresses away what you need to unambiguously discriminate between two symbols.

And to get to that level of density I do wonder what kind of detailed "real image" it would still be.

If your algorithm were for example literally the example you just noted, then the "big enough colorful pixels" from the example video already massively outperform your algorithm. Of course it won't be exactly that, but you have the assumption that the video compression algorithm somehow applies the same meaning of "looks like" in its preservation efforts that your machine learning algorithm does, down to levels where differences become so minute that they exceed what you can do with colorful pixels that are just big enough to pass the compression unscathed, maybe with some additional error correction (i.e. exactly what a very high density QR code would do).

Re: YouTubeDrive: Store files as YouTube videos

#253
This gave me a flashback of VBS on amiga… video backup system, record composite video on a vcr, and simple op amp circuit that would decode black and white blobs of video pixels, could backup floppies at reading speed. Was really impressive until, well, vhs… ;)

Just did a google and saw it had evolved over the years, used only the 1.0 implementation back in the days. For those on another nostalgic trip : http://hugolyppens.com/VBS.html

Re: YouTubeDrive: Store files as YouTube videos

#254
post #118

I only looked at the example video, but is the concept just "big enough pixels"? Would be neater (and much more efficient) to encode the data such that it's exactly untouched by the compression algorithm, e.g. by encoding the data in wavelets and possibly motion vectors that the algorithm is known to keep[1]. Of course that would also be a lot of work, and likely fall apart once the video is re-encoded. [1] If that's…

Agree it would be cool to be "untouched" by the compression algorithm, but that's nearly impossible with YouTube. YouTube encodes down to several different versions of a video and on top of that, several different codecs to support different devices with different built-in video hardware decoders. For example, when I upload a 4K vid and then watch the 4K stream on my Mac vs my PC, I get different video files solely b…

Just as an aside, it's absolutely astounding how much hardware Google must throw at YouTube to achieve this for any video anybody in the world wants to upload. The processing power to reencode to so many versions, and then to store all of those versions, and then make all of those accessible anywhere in the world at a moments notice. Really is such an incredible waste for most YouTube content.

Re: YouTubeDrive: Store files as YouTube videos

#255

Earlier quoted context omitted.

Do you have any idea how many more bits you'd be able to use if you applied any of the encoding transformations?

I'd estimate that there's an easy order-of-magnitude improvement (~10x) just from implementing a simple error-correction mechanism -- a Reed-Solomon code ought to be good enough that we can take the squares down to 10x10, maybe even 8x8 or 5x5. Then, if we really work at it, we might be able to find another order-of-magnitude win (~100x) by packing more bits into a frequency-domain encoding scheme. This would likely…

> that we can take the squares down to 10x10, maybe even 8x8 or 5x5

16x16, 8x8, or 4x4 would be the way to go. You'd want each RGB block to map to a single H.264 macroblock.

Using non order of 2 numbers means that individual blocks don't line up with macroblocks. Having a single macroblock represent 1, 4, or 16 RGB pixels would be ideal.

In fact, I bet modifying the original code to use a scaling factor of 16 instead of 20 would produce some significant improvements.

Re: YouTubeDrive: Store files as YouTube videos

#257

Earlier quoted context omitted.

Hm, I thought she was popular in the mid '90s, but maybe it was more like the '00s?

No I'm pretty sure you're right on the timing. I was a teenager in the mid to late 90s and britney tapes were extremely common then, to the point that it was often used as a joke (much like in your story!)

WinMX was release 21 years ago, and Britney Spears definitely didn’t break out until around 1999 around the same time as Napster. The difference between 1994 and 1999 is quite a bit in show biz/pop culture and an absolutely huge difference in public uptake of the internet.

Re: YouTubeDrive: Store files as YouTube videos

#260

Hey everybody! I'm David, the creator of YouTubeDrive, and I never expected to see this old project pop up on HN. YouTubeDrive was created when I was a freshman in college with questionable programming abilities, absolutely no knowledge of coding theory, and way too much free time. The encoding scheme that YouTubeDrive uses is brain-dead simple: pack three bits into each pixel of a sequence of 64x36 images (I only us…

As far back as the late 1970s a surprisingly similar scheme was used to record digital audio to analog video tape. It mostly looks like kind of stripey static, but there was a clear correlation between what happened musically and what happened visually, so in college (late 1980s) one of my friends came into one of these and we'd keep it on the TV while listening to whole albums. We had a simultaneous epiphany about the encoding scheme during a Jethro Tull flute solo, when the static suddenly became just a few large squares.

Can see one in action here

https://www.youtube.com/watch?v=TSpS_DiijxQ

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