recreate divx compression error

akee-rf's icon

Hi there,
i'm trying to recreate that compression error that we can see on divx especially with VLC with you are seeking or when you re doing a preview a movie you are downloading before the download is done..
(the image freeze or partialy freeze and it looks like the animation is still running on the back changing the actuall image .. kind of morphing stuff..)

if somebody have an idea of where to start...

thanks a lot

freeka

yair reshef's icon

i tried that once. even asked that same question in doom9 and got some scary
looks.
you can try to do a 2pass encoding and before the second pass fiddle with
the numbers in the first pass generated txt file. thats kinda funky but not
that predictable.
ye, that effect is great and i love it when it happens.
when i think about it it can be done in jitter with cv.jit pixel flow
tracker and some op.

On Jan 21, 2008 5:13 PM, freeka wrote:

>
> Hi there,
> i'm trying to recreate that compression error that we can see on divx
> especially with VLC with you are seeking or when you re doing a preview a
> movie you are downloading before the download is done..
> (the image freeze or partialy freeze and it looks like the animation is
> still running on the back changing the actuall image .. kind of morphing
> stuff..)
>
> if somebody have an idea of where to start...
>
> thanks a lot
>
> freeka
>

akee-rf's icon

hey thanks for your reply!
cv.jit pixel flow tracker ?? what do you mean??

you re talking about the cv.jit.tracker????

vade's icon

The issue here is that jitter gives you the decoded pixels, whereas
the 'image processing' happens during the decoding stage within the
divx codec itself, which is somewhat out of jitters realm, so you
would have to do 'glitch alike', and reverse engineer the look with
expensive pixel operations.

Ive often fantasized about a set of jitter objects that let you:

1) read raw data off disk and pass a matrix through somehow
2) munge its binary data with jit.op whatevers before:
3) passing this raw encoded binary matrix to various different
jit.decode.jpeg, jit.decode.png etc software decoders, or perhaps
automatic objects that wrap around installed qt components

thus you might have just a new jit.encode and jit.decode, which would
perhaps take in a binary stream, and output a 4 char matrix of size
determined by the binary stream, and with jit.encode you would have a
4 char matrix whatever dim producing a jit.encoded binary stream output.

You could then do things super easily like finding harmonics in video
encoders by feeding back the output of the jpeg decoder to the jpeg
encoder with a jit.xfade for feedback... live!

fuck yes. Would be amazing.

On Jan 21, 2008, at 10:40 AM, yair reshef wrote:

> i tried that once. even asked that same question in doom9 and got
> some scary looks.
> you can try to do a 2pass encoding and before the second pass fiddle
> with the numbers in the first pass generated txt file. thats kinda
> funky but not that predictable.
> ye, that effect is great and i love it when it happens.
> when i think about it it can be done in jitter with cv.jit pixel
> flow tracker and some op.
>
> On Jan 21, 2008 5:13 PM, freeka < freeka.freeka@gmail.com> wrote:
>
> Hi there,
> i'm trying to recreate that compression error that we can see on
> divx especially with VLC with you are seeking or when you re doing a
> preview a movie you are downloading before the download is done..
> (the image freeze or partialy freeze and it looks like the animation
> is still running on the back changing the actuall image .. kind of
> morphing stuff..)
>
> if somebody have an idea of where to start...
>
> thanks a lot
>
> freeka
>

akee-rf's icon

word!
but until we get that we can lick our bones :D

akee-rf's icon

hum i had a look on the jitter recipe book
40.scenewarp... which is actually a good start i think do you think
i dunno about the jit.gl stuff.. but do you think its possible to put a second video on the back to substitute the white screen that appear when we start the deformation? Puting the same video but without the deformation will be great!

Andrew Benson's icon

The Debris recipe does a passable job of collecting bits of pixel trash
in real-time, if that is what you are looking for. Trying to mimic an
aesthetic or effect is a great learning exercise, and you often come up
with great ideas in the process, even if it doesn't end up looking just
right. Let us know what you come up with

Andrew B.

nesa's icon

Here's my clumsy tryout of 'divx' effect recreation, I think it's the
same idea Yair mentioned - cv.jit.hsflow+jit.repos.
It's quite heavy&dirty since this is one of those train patches('make
it clean' vs 'end up in Dordrecht').

best,
nesa

Max Patch
Copy patch and select New From Clipboard in Max.

eth1394's icon

i recently experienced *amazing* compression errors by simply
exporting a video via [jit.qt.record] using the "sorenson" codec.

it actually outperforms divx in terms of glitch aesthetic.

./eth

>Hi there,
i'm trying to recreate that compression error that we can see on divx
especially with VLC

Wetterberg's icon

freeka skrev:
> Hi there,
> i'm trying to recreate that compression error that we can see on divx especially with VLC with you are seeking or when you re doing a preview a movie you are downloading before the download is done..
> (the image freeze or partialy freeze and it looks like the animation is still running on the back changing the actuall image .. kind of morphing stuff..)
>
haha, I have been sooooo wondering about that thing since getting into
Jitter. As an aside, I wonder if people are documenting those kinds of
errors online, or even deliberately creating them?

The weirdest error I ever saw was in a movie where the main character
walked around with a fragment of old video plastered across his face,
wrapped to conform to his face - FREAKY!

Gideon Kiers's icon

i think benjamin's on this list as well ..

On 22 jan 2008, at 16:47, Andreas Wetterberg wrote:

> haha, I have been sooooo wondering about that thing since getting
> into Jitter. As an aside, I wonder if people are documenting those
> kinds of errors online, or even deliberately creating them?
>
> The weirdest error I ever saw was in a movie where the main
> character walked around with a fragment of old video plastered
> across his face, wrapped to conform to his face - FREAKY!

Gideon Kiers's icon

some video's here :

On 22 jan 2008, at 18:21, Gideon Kiers wrote:

> check : http://www.corrupt.ie/
>
> i think benjamin's on this list as well ..

akee-rf's icon

Hey Nesa
thanks for your patch!! the movement and animation on the pixel are really good, do you think there is a way to remove this grain stuff
to more the original file ??
what i'm looking for is that sort of wave/deformation around the movement you get on your patch..

thanks all the guys who are in touch!

yair reshef's icon

nesa thats cool

On Jan 22, 2008 7:33 PM, freeka wrote:

>
> Hey Nesa
> thanks for your patch!! the movement and animation on the pixel are really
> good, do you think there is a way to remove this grain stuff
> to more the original file ??
> what i'm looking for is that sort of wave/deformation around the movement
> you get on your patch..
>
> thanks all the guys who are in touch!
>
>
>

nesa's icon

trying to follow up...

On Jan 22, 2008, at 6:33 PM, freeka wrote:

> this grain stuff
> to more the original file ??

instead of using jit.noise, you can occasionally send the original
movie matrix...
add some feedback in the mix, and it's even tastier:

Max Patch
Copy patch and select New From Clipboard in Max.

akee-rf's icon

you rules!

i will look more into it now

thanks a lot

akee-rf's icon

Hey Nesa,
your patch is really great,
i think it need now just a lil thing:
when you perform the destruction,if i understood well, the patch decompose the screen into several square area and move them using the hsflow as reference right?
it will be perfect to have different square area size, more random size as the real divx error, maybe grouping the area by color or something, but maybe really hard to do..
if you have any idea?

Adding an alphabend between the wet signal and the raw signal at the end is good to eliminate the black zone coming with the derformation..

thanks

akee-rf's icon

kind of funny to read that post again 4 year after Ö

Timo's icon

And 7 years later?

Did you find any new ways to play around with 'decoding' effects? I worked with the vipr external and used different compression settings. This way you can creat some nice effects... but I'm looking for other possibilities and I'm very curious on what you came up with!
Greetings & thanks for suggestions

Timo