Digital Cinema Package

[Pavel Klepinin]

Pavel, hi, had your question stored in the back of my mind and just bumped into "Stereoscopic Rendering in Blender" (http://www.noeol.de/s3d/). Math and blender workflow.

Thnx very much. It looks really useful. I'll try to make some parallax in 3D Render. I used to do it in After Effects, hardly without correct math understanding.
Looking forward for an efficient weekend
BTW, for russian-speaking users we've made a theme on our forum.

 

[Sulio Pulev]

i had a numbers of fails, when dcp works fine easydcp player, but it doesn't on my server. The problem was in my script - some errors in "if". It caused by not fillin' all the script vars. Did you fill all of the script variables?

Ишь ты , нахаляву захотел. В етом деле халявы не бывает тем более в Пензы . Откажься от етом деле, а то прийдут ОМОН и посмотрят на ВАШИ компютеры откуда софт взялся и всем будет п....ц. Ишь ты, захотелось пацану 3Д нахаляву делать бабло нажить.

 

[Pavel Klepinin]

Ишь ты , нахаляву захотел. В етом деле халявы не бывает тем более в Пензы . Откажься от етом деле, а то прийдут ОМОН и посмотрят на ВАШИ компютеры откуда софт взялся и всем будет п....ц. Ишь ты, захотелось пацану 3Д нахаляву делать бабло нажить.

I didn't realy understand what are you going to say, but thanx to Wolfgang, OCT creators and some other good users of this forum, I've managed to transform film into DCP for free. My goal is not to get money from this transformations. I share my experiments and my script for free. Maybe my goal is opposite. Anyone could make this, even if he is from Penza :blush5:
ps Your russian is awful. Shame on you if you're a russian-speaking person.

 

[Terrence Meiczinger]

I still haven't had much luck getting an MPEG2 to work properly. There must be a flag or some other setting missing when using ffmpeg to create the stream. I can create a DCP using jpeg2000s, so most of the workflow seems correct. It will be nice to figure out the mpeg, since it can potentially save a lot of time, especially when the source is already mpeg2.

I'm developing a software package that simplifies everything into a one-step process. I forgot how much I dislike building GUIs.

 

[Thrane]

Thank you for the great guide!
I managed to make a simple 15 sec piece (no sound) and tested it in the local cinema...
BUT!
Hope you guys can help med out here!

The colors are just so wrong!
The look like I have taken a CMYK photo and viewed in RGB - the colors are very bright.

Any ideas on how to get the correct colorspace?

Thanks!

 

[Pavel Klepinin]

Thank you for the great guide!
I managed to make a simple 15 sec piece (no sound) and tested it in the local cinema...
BUT!
Hope you guys can help med out here!

The colors are just so wrong!
The look like I have taken a CMYK photo and viewed in RGB - the colors are very bright.

Any ideas on how to get the correct colorspace?

Thanks!

What guide did you use?
Have you made some colorspace transformations and gamma correction (for exc. by ImageMagik - "convert <frame> -alpha Off -depth 12 -gamma 0.454545 -recolor "0.4124564 0.3575761 0.1804375 0.2126729 0.7151522 0.0721750 0.0193339 0.1191920 0.9503041" -gamma 2.6") ?

 

[Thrane]

Used the guide on page 1 in this thread to make a DCP, but haven't followed any guide regarding the colorspace.
Tried "normal" RGB and also LAB color as I read somewhere that I had to use CIE XYZ?

 

[Thrane]

Now I have downloaded ImageMagick, but I'm not good at that kind of programs.
I need and interface... :-(

 

[Pavel Klepinin]

I'm affraid there is no GUI for DCP-making with colorspace correction, for now.
But you can use my bat-script (for Windows) if you want.

 

[Thrane]

Thanks, will have a look.
My problem is only to get the right colorspace.
Making the DCP is no problem....

 

[M Most]

I'm affraid there is no GUI for DCP-making with colorspace correction, for now.

Sure there is, at least for the colorspace conversion part. It's called Adobe After Effects. But it's not open source.

 

[Thrane]

I'm using After Effects for making a tiff sequence, but again, the problem is the wrong colorspace.
What are the correct settings to get the CIE XYZ as output?
If thats what I need?

 

[M Most]

I'm using After Effects for making a tiff sequence, but again, the problem is the wrong colorspace.
What are the correct settings to get the CIE XYZ as output?
If thats what I need?

Without going through things step by step, read the Adobe white paper on color management in After Effects. It tells you everything you want to know.

 

[Pavel Klepinin]

I'm using After Effects for making a tiff sequence, but again, the problem is the wrong colorspace.
What are the correct settings to get the CIE XYZ as output?
If thats what I need?

You can save your clip as tiff sequence using X'Y'Z' colorspace, and then use OCT GUI to biult dcp. Check some first pages, there was a correct advice.

 

[Eren Ozkural]

Just read the walkthrough...this is seriously one of the coolest posts I have ever read on REDUSER Leerafel. Well done.

I especially like the fact that I have everything I need at hand beside the Easy DPX license.

Now, to find a booth manager in London whose feeling generous...

 

[Priit Poldmaa]

Doing here my first conversions to DCP for a local indie feature.
Got my first pakage with Opencinematools today.
Wolfgang, Pavel, Chris etc have given an invaluable information here.

But one aspect worries me.
With the ImageMagick sample the conversion is from sRGB to X'Y'Z' P3.
-gamma 0.454545 -recolor "0.4124564 0.3575761 0.1804375 0.2126729 0.7151522 0.0721750 0.0193339 0.1191920 0.9503041"

What coeficents shoud I use if the source is Rec.709?
Got the original as BlackMagic 10-bit uncompressed video and converted to DPX files with Combustion. Gamma was left as original.

Thanks
Priit

 

[Wolfgang Woehl]

priitp,

see http://github.com/wolfgangw/digital_cinema_tools/blob/master/rec709-xyz_matrix.rb for the exact numbers and source code to check those numbers.

 

[Priit Poldmaa]

Thanks Wolfgang.
Have see it earlier but forgot already.

What about gamma?
As Rec.709 gamma has a linear part it is not so easy to deal it with Imagemagic convert -gamma.
Let's say we use one value for gamma but what might it be?

I remember Michael Most wrote somewhere that "Rec709 is described as having a specific gamma that is somewhere around 2.3 or so (but not exactly, the lower end of the curve is a bit different)"

So will this be the best bet? -gamma 0.434783

It seems to me it would be good to have a 1D LUT for linearisation.
I have to check the -clut possibilties.

Priit

 

[M Most]

I remember Michael Most wrote somewhere that "Rec709 is described as having a specific gamma that is somewhere around 2.3 or so (but not exactly, the lower end of the curve is a bit different)"

I might have said that, and it's not inaccurate. The real problem with Red709 is that there is no definition for a reference display, in fact, there is no display definition at all, as opposed to, say, the DCI P3 specification. I'm told Charles Poynton is currently working on trying to rectify that, among other things.

 

[Priit Poldmaa]

Thanks Michael for the input.

Unfortunatelly ITU Rec.709 standard is not freely available.

From Cine-tal forum here found this formula:
-----------------------------------------------------------------------
Overall opto-electronic transfer characteristics at source:

V = (1.099 * L^0.45) - 0.099 for 1 ≥ L ≥ 0.018
V = 4.5 * L for 0.018 > L ≥ 0
where:
L: luminance of the image 0 ≤ L ≤ 1
V: corresponding electrical signal
-------------------------------------------------------------

Not sure how reliable is this source.
Meaning to make a -clut image based on it.

Priit