

Guy uploads, downloads, then re-uploads the same video to YouTube 1,000 times - jazzychad
http://slate.me/bNg1lh

======
dangrossman
Was the aspect of using YouTube's servers so critical to the artistic quality
of this project that he couldn't just substitute a shell script that encodes
the video 1000 times over? Would've taken a heck of a lot less time than the
year he spent.

~~~
jazzychad
Perhaps, in addition to the artistic aspect of it, he wanted to educate people
about what actually happens to video when it is sent to youtube. This is much
more relatable than saying, "I wrote this shell script..." Also, having the
log of all 1000 versions on youtube is interesting as well.

The other thing about art is that time is usually not a large motivating
factor...

~~~
jemfinch
The thing is, I'm not convinced that it's youtube's fault; apparently he
converted it to mp4 on his own computer after the download from youtube,
before re-uploading it. I wonder if he'd have had the same effect if he'd
uploaded the same format he ripped from youtube.

~~~
megablast
Nobody is blaming youtube, video compression or anything of the such. This is
to expected behaviour. And no normal person should be able to expect, or want
to upload and download a video 1000 times, or even more than 10.

------
mmaunder
What's the difference between an artist and a Perl programmer? 364 days and 23
hours.

~~~
jrockway
And the Perl programmer has disposable income and a girlfriend.

~~~
nandemo
Wait, in what part of the world is a programmer more likely than an artist to
have a girlfriend?

~~~
jrockway
Ones where girls like the guy to buy them food?

------
MikeCapone
#1000 looks like an alien from another dimension trying to communicate with
us.

It's the modern version of photocopying something tons of times..

Certainly a good education about lossy compression for the non-technical
public.

------
presidentender
The HN community could have saved a lot of time writing a shell script to post
a snide comment about writing a shell script from every account instead of
forcing everyone in the thread to do it individually.

~~~
ErrantX
I think that, simply, this sort of art is quite different from what large
parts of the HN crowd would consider artistic/beautiful.

(personally: doesn't do anything for me as art)

------
chaosmachine
The "Angry Video Game Nerd" guy did a similar thing with two VHS tapes,
copying a video back and forth over and over:

<http://www.cinemassacre.com/2010/05/26/vhs-generation-loss/>

~~~
igravious
so: prior art?!

~~~
studer
It's his take on Alvin Lucier's famous "I Am Sitting in a Room":

<http://www.youtube.com/watch?v=Jfssj80oNuM>

The original recording is linked from the Mashable article.

------
idoh
I did something like this - I took an image and rotated it a couple hundred
times in Windows Explorer. It gradually degraded into a blurry blob.

~~~
sp332
Which is pathetic, since it's possible to do a lossless (I mean not
incrementally lossy) rotation of JPG's.

~~~
pbhjpbhj
MS Windows (XP IIRC) used to warn you if you used the built in image rotation
function for JPEGs that it was lossy. I've a feeling it was fixed in SP2 but
I've not used MS Win for years so am not really sure.

~~~
TeHCrAzY
Win Vista & 7 don't have this problem (just checked).

~~~
idoh
I did this in 1997 or 1998.

------
illumin8
Sometimes this effect of multiple lossy compressions is very apparent on
certain... ahem... adult sites, which steal content from other adult sites.
When the content has been decompressed and recompressed enough times certain
artifacts start to appear, as well as other issues like aspect ratio problems.

------
yanowitz
Does this mean YouTube's compression settings don't target a specific bit-rate
but instead aim to make it "no larger than X and at least y% smaller" than
what was uploaded?

I'm surprised it's not just a pass-through at a certain point (if nothing
else, that'd save CPU cycles).

~~~
zokier
<http://news.ycombinator.com/item?id=1402382>

Apparently it was himself who re-encoded the video, not youtube. Dont know
where jemfinch got that info though.

~~~
daten
And youtube serves content in different resolutions (SD vs HD) and formats
(flash vs ipod). It's possible his choice of either of these had a negative
effect on the quality. It's also possible it all happened during his on
conversion on his local machine.

I wonder what results he would have gotten if he pulled the h264 copy down
that is served to apple devices and uploaded it without modifying it.

------
slackito
The process reminds me of this post:
[http://hackerfactor.com/blog/index.php?/archives/355-How-
I-M...](http://hackerfactor.com/blog/index.php?/archives/355-How-I-Met-Your-
Mother-Through-Photoshop.html)

~~~
jpablo
Great post, I wonder if the trick that photoshop is pulling is really
beneficial or worse in the long term.

------
Vivtek
What's really cool about this is that his stated purpose ("to remove all human
characteristics from both my voice and my image") is fulfilled by his voice
and the individual frames - but the way the shapes _move_ is still very human.
A lot more human than CGI animation is still doing, actually.

That's neat.

------
bg4
Now he needs to splice them all into a single video showing the gradual
degradation over time.

------
twodayslate
My speakers were on full blast - the 1,000th uploaded one scared the crap out
of me! :O

------
JoeAltmaier
I'm surprised it continued to change after detail was lost. Seems like there
would be some measurable property of a codec/decode process that could be
quantified - the entropy? It would be a desirable property to be 'idem-
potent', e.g. after one cycle the result settles.

~~~
pyre
> _codec/decode_

I think that you meant: 'code/decode.' 'codec' is a abbreviation for
'code/decode.'

------
ars
I can understand the video getting messed up, but what happened to the audio?
From what I understand re-encoding an mp3 doesn't do much - all the waveforms
that were going to be thrown out, were already the first time. On the second
pass nothing much changes.

Or did he rip the video using speakers and mic, rather than downloading the
digital data from youtube?

I have a feeling the errors came during the ripping process, not the encoding
process.

~~~
celoyd
_re-encoding an mp3 doesn't do much_

Sure it does, typically. It’s no different from video in this way: ideally,
all of the image features that would get thrown out were thrown out the first
time, but the codec isn’t that smart.

Most implementations of lossy compression algorithms don’t have stability
under re-encoding as a goal. (A few do – some image editors are smart about
passing through unchanged JPEG blocks, for example, and I think mp3wrap will
join MP3s cleanly.)

I’m too lazy to look into exactly how he did this, but it’s not impossible
that the audio artifacts came from pure MP3^ _n_ re-encoding. It’s a case that
most compressors ignore.

~~~
jerf
Why hypothesize? Create a directory. Copy your favorite MP3 into it as both
"source.mp3" and "orig.mp3". (orig.mp3 is just for convenient comparison
later.) Then:

    
    
        for i in {1..100}; do lame source.mp3 dest.mp3; mv -f dest.mp3 source.mp3; done
    

Then listen to the resulting "source.mp3" at the end. Send whatever params to
lame you want in that command line, though the defaults strike me as pretty
good for this test.

BTW, when people point out that scripting this is easy, they're not kidding.
We're talking shell one-liner here, forget even hitting perl.

I'm on about iteration 7 as I write this and it's definitely breaking down.

~~~
jokermatt999
[http://www.reddit.com/r/technology/comments/86yiq/hear_what_...](http://www.reddit.com/r/technology/comments/86yiq/hear_what_happens_when_you_reencode_an_mp3_600/)

A reddit post on that exact experiment. Sadly, the file is down.

As a side note, I had a post here that I deleted about this, worded something
like "Yes, they used _that_ song". I went back to read the topic, and found
I'd made nearly the exact same comment on the story over a year ago. I guess
I'm a tad predictable.

Edit: Aha! A megaupload link was posted that still works.
<http://www.megaupload.com/?d=ALZY0LCD>

Also related, the same experiment but for .jpg:
[http://www.reddit.com/r/technology/comments/86v2z/see_what_h...](http://www.reddit.com/r/technology/comments/86v2z/see_what_happen_when_saving_600_times_a_jpg_image/)

~~~
ars
That file only increased my questions on what happened to the audio on this
vid. The song is quite recognizable. So why did the youtube one turn into
garble?

And the jpg one is just incorrect. He kept increasing the compression ratio,
which proves nothing at all. For a more accurate view see
[http://hackerfactor.com/blog/index.php?/archives/355-How-
I-M...](http://hackerfactor.com/blog/index.php?/archives/355-How-I-Met-Your-
Mother-Through-Photoshop.html) which shows that after a certain point the jpeg
stops changing. (Which is what I expected the mp3 to do, but I guess it
doesn't.)

~~~
jokermatt999
The mp3 is probably using a different audio codec than the youtube video/mp4.

------
bdr
Here's the inspiration: <http://en.wikipedia.org/wiki/I_Am_Sitting_in_a_Room>

------
kree10
I wasn't familiar with the audio piece that inspired this so I downloaded the
mp3 from <http://www.ubu.com/sound/lucier.html> . It turned out to be a nice
background soundtrack for programming today.

Music with words usually distracts me when I'm working, but this didn't.

------
stellar678
It's really interesting to note the differences in our perceptions of the
final audio versus the final video.

The video, while severely degraded, is obviously still a human figure moving
around.

The audio, on the other hand, is mangled completely beyond recognition.

------
jsz0
Next time the topic of bandwidth caps comes up remember this guy. I don't want
to knock his project but I think it illustrates a point that unlimited
bandwidth and access to services tends to make people less concerned about
using bandwidth efficiently.

~~~
mos1b
He used hundreds of hours of his time. What makes you think he would've
refrained from paying a few extra dollars for the bandwidth?

~~~
jsz0
Nothing. I'm sure he probably would have if forced to. I know from my own
(bad) habits I often waste bandwidth just because I can. Common example of
this is having a file downloaded to my laptop sitting in my backpack but
instead of taking it out, waking it up, mounting the share and copying it I'll
just re-download it from the Internet instead because I'm lazy and there's
really no downside for me.

------
kurtosis
I'm too lazy to look this up, but did the video get smaller or larger with the
iteration number? This is more interesting to me than the look

~~~
kylemathews
Time: yes File size: yes

Not sure why the time dropped.

~~~
faboo
I'm not a video expert, but I did write some software for muxing and demuxing
for a company I worked for some time ago. The major problem I had was that
video and audio are stored at different "frame rates" (almost in a literal
sense). A frame of encoded audio is generally shorter (in seconds of playback)
than a single video frame is displayed on screen for. So, if you were cutting
and splicing video, you'd end having to decode the audio, break apart the
first and last frame's worth of it, re-encode it, and then offset the timing
of the audio from the video. This is very obnoxious to get perfect.

I've got no idea if that's what impacted this guy's video though, but I'm sure
it's far from the only weird thing involved in video compression.

------
gills
Wow. It's like a lesson in wavelet transforms for the layman. But without ever
using the word 'wavelet.' Cool.

------
oomkiller
He probably could have saved a lot of time with a shell script :)

------
bitwize
I bet Christopher (prawn protagonist of _District 9_ ) might be able to grok
the bizarre utterances in the 1000th video... but I can't.

------
ddemchuk
I'm sure Youtube loved getting spammed with a 1000 very similar videos

~~~
matthew-wegner
Probably not as much as they loved an interesting story about YouTube on
prominent websites.

~~~
ddemchuk
come on now, it's youtube, they're the second most used search engine in the
world. They don't really need good press anymore

