Amazing Scratch Magic Trick / Challenge! [Solved! (mostly)]

novice27b

(Sorry for the slightly clickbaity title - I don't want to spoil the surprise!)
I've figured out a pretty cool trick with Scratch. To try it out, follow these steps:

1. Download scratch_audio.wav. (Hosting courtesy of @Jonathan50/github)
2. Create a new Scratch project.
3. Upload the audio file.
4. Play the audio file in Scrach. (It's just a random section of a song)
5. Let the project autosave, and then refresh the page.
6. Play the audio again. You should notice something unusual.

Here are some challenges, in order of difficulty:

1. Identify the first song. (Winner: @liam48D)
2. Work out how it works. (Winner: @WooHooBoy, very close second: @Dylan5797)
3. Replicate the effects.

I'm guessing that challenge 2 will be quite easy for some of the more advanced users here, so please don't post a solution just yet - prove that you know, without actually saying how it works.

PS: My sig survived the recent mass-resetting

(And I found a new way to get redirects, even if it does get reset!)

Last edited by novice27b (Jan. 20, 2016 19:02:30)

i use arch btw

WooHooBoy

spoilers, highlight if you want to be spoiledI'm assuming scratch's compression is lazy, and just takes every nth tone? So you make a regular song and then put rickroll in it every nth tone.

considered harmful

novice27b

WooHooBoy wrote:
spoilers, highlight if you want to be spoiledI'm assuming scratch's compression is lazy, and just takes every nth tone? So you make a regular song and then put rickroll in it every nth tone.

Nope, guess again! That's an interesting idea though, I might try it out.

Last edited by novice27b (Jan. 19, 2016 19:26:44)

i use arch btw

WooHooBoy

novice27b wrote:
WooHooBoy wrote:
spoilers, highlight if you want to be spoiledI'm assuming scratch's compression is lazy, and just takes every nth tone? So you make a regular song and then put rickroll in it every nth tone.

Nope, guess again! That's an intresting idea though, I might try it out.

It does have to do with compression tho?

considered harmful

novice27b

WooHooBoy wrote:
novice27b wrote:
WooHooBoy wrote:
spoilers, highlight if you want to be spoiledI'm assuming scratch's compression is lazy, and just takes every nth tone? So you make a regular song and then put rickroll in it every nth tone.

Nope, guess again! That's an intresting idea though, I might try it out.
It does have to do with compression tho?

Nope, nothing to do with compression.

i use arch btw

WooHooBoy

novice27b wrote:
WooHooBoy wrote:
novice27b wrote:
WooHooBoy wrote:
spoilers, highlight if you want to be spoiledI'm assuming scratch's compression is lazy, and just takes every nth tone? So you make a regular song and then put rickroll in it every nth tone.

Nope, guess again! That's an intresting idea though, I might try it out.
It does have to do with compression tho?
Nope, nothing to do with compression.

Oh okay then.
hint?

considered harmful

novice27b

WooHooBoy wrote:
novice27b wrote:
WooHooBoy wrote:
novice27b wrote:
WooHooBoy wrote:
spoilers, highlight if you want to be spoiledI'm assuming scratch's compression is lazy, and just takes every nth tone? So you make a regular song and then put rickroll in it every nth tone.

Nope, guess again! That's an intresting idea though, I might try it out.
It does have to do with compression tho?
Nope, nothing to do with compression.
Oh okay then.
hint?

Nope, no hints yet! I might if nobody gets it in a couple of days.

i use arch btw

Jonathan50

they delay your download on purpose -_- (well at least they aren't evil and give you viruses and spam you with ads and stuff)
uploading to GH Pages

http://jonathan50.github.io/scratch_audio.wav

Not yet a Knight of the Mu Calculus.

novice27b

Jonathan50 wrote:
they delay your download on purpose -_- (well at least they aren't evil and give you viruses and spam you with ads and stuff)
uploading to GH Pages

http://jonathan50.github.io/scratch_audio.wav

Thanks. I'll put that link in the OP.

i use arch btw

liam48D

My first assumption is something to do with compression, with that busted I'd say something else to do with saving/loading the sound (duh). Time to browse the source

202e-202e-202e-202e-202e UNI-CODE~~~~~

novice27b

Here's a hint: The same technique will also work with images.

I'm going to use that make a project that changes its behaviour entirely after the first refresh.

Last edited by novice27b (Jan. 20, 2016 18:35:03)

i use arch btw

liam48D

Got it! Qwentalis / Tears of Stone

EDIT: Here's the point in the song where the clip is for lazy people who don't want to listen to a five minute song: https://youtu.be/jVactbpfx-Y?t=1m19s

Last edited by liam48D (Jan. 20, 2016 18:29:08)

202e-202e-202e-202e-202e UNI-CODE~~~~~

novice27b

liam48D wrote:
Got it! Qwentalis / Tears of Stone

EDIT: Here's the point in the song where the clip is for lazy people who don't want to listen to a five minute song: https://youtu.be/jVactbpfx-Y?t=1m19s

This version is better IMHO: https://soundcloud.com/qwentalis-masters/tears-of-stone
(It's also where I took my sample from)

Congrats!

Last edited by novice27b (Jan. 20, 2016 18:42:15)

i use arch btw

WooHooBoy

does it have to do with md5 collisions?

considered harmful

Dylan5797

You used the asset api to set the md5 digest of the first song to the second one, it works because assets can't be overwritten. Proof: https://cdn.assets.scratch.mit.edu/internalapi/asset/a24945fc02b8a50e04c25a34aad4592f.wav/get/

nice job finding a duplicate md5 :)
unless you're using some other hack :P

Last edited by Dylan5797 (Jan. 20, 2016 18:47:10)

WooHooBoy

Dylan5797 wrote:
You used the asset api to set the md5 digest of the first song to the second one, it works because assets can't be overwritten. Proof: https://cdn.assets.scratch.mit.edu/internalapi/asset/a24945fc02b8a50e04c25a34aad4592f.wav/get/

nice job finding a duplicate md5 :)

You just got ninjad.

considered harmful

Dylan5797

WooHooBoy wrote:
Dylan5797 wrote:
You used the asset api to set the md5 digest of the first song to the second one, it works because assets can't be overwritten. Proof: https://cdn.assets.scratch.mit.edu/internalapi/asset/a24945fc02b8a50e04c25a34aad4592f.wav/get/

nice job finding a duplicate md5 :)
You just got ninjad.

Nooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo

at least i proved it

also i saw the asset setting request with content-length in the response set to -1

Last edited by Dylan5797 (Jan. 20, 2016 18:50:22)

WooHooBoy

Dylan5797 wrote:
WooHooBoy wrote:
Dylan5797 wrote:
You used the asset api to set the md5 digest of the first song to the second one, it works because assets can't be overwritten. Proof: https://cdn.assets.scratch.mit.edu/internalapi/asset/a24945fc02b8a50e04c25a34aad4592f.wav/get/

nice job finding a duplicate md5 :)
You just got ninjad.
Nooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo

http://advancedofftopics.gwiddle.co.uk/forums/index.php?p=/discussion/142/did-this-ever-happen

Wow, I ninja'd myself and novice!

what?

considered harmful

novice27b

We have a winner!

i use arch btw

Dylan5797

novice27b wrote:
We have a winner!

aww so close

at least partial credit?

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