How do they convert b/w films into colour?

shaan_aragorn

i've seen a film which was orignally black and white but after 50 years or so they made it colour. how did they do it?

Danger

They basically just 'paint' every element with the colour that they think belongs there. It's all pretty much computerized now, so things like shading remain undisturbed.

shaan_aragorn

But, how does the computer know if this particular dress was blue or say red?
How are colours decided?

Evo

In some cases it might be known what color a famous dress was, but for most, they just arbitrarily pick a color.

Astronuc

There are sometimes color pictures (stills) for advertisements, or paintings of the actors or actresses in character.

Otherwise, someone has to go off grey scales.

ray b

color stills and movie posters
plus popular colors at that time [or at the time of conversions]
plus whatever ''they'' think looks good
or read a grays scale of a known color [red rose] and convert other stuff to like colors
as it is art not science what ever they want is the color it winds up being

shaan_aragorn

but a second has 25 frames, do they paint every frame? that will take enormous amount of time and money

Danger

It's certainly an involved process, but it's done digitally now. When thinking of doing it manually, though, don't forget that things like 'Fantasia' were not only coloured, but also drawn by hand... one frame at a time.

shaan_aragorn

wow, how much time does that take?

Danger

I can't find anything definitive. IIRC, there were at least a dozen artists working on Fantasia for a couple of years. It was originally supposed to be just Mickey Mouse directing 'The Sorceror's Apprentis', but they had to add the other pieces to make it profitable. It progressed in fits and starts.
Snow White was in production for 3 years, but I don't know how much of that was the artwork or how many artists were involved.

mgb_phys

I don't know if this is the techniques used in hollywood but this demonstration is amazing http://www.cs.huji.ac.il/~yweiss/Colorization/

Danger

Wow! I've tried to keep up with things, but I've sure never seen anything that sophisticated. Nice link.

FrogPad

wow... ....................................................................... .........

Danger

Hey, Shaan;
This just popped up on 'How Stuff Works' today.
http://entertainment.howstuffworks.com/question184.htm

DaveC426913

Modern software is smart enough to track objects from frame to frame. So you tag one frame with the colours you want, and the computer does the rest. That's a huge simplification, but it's not like they have to colour every frame.

Danger

But, as the link mentions, it has to be checked every dozen frames or so. The process that Mgb phys brought up is way beyond what is currently being used commercially.

Barry_Sandrew

Check out Legend Films, Inc. (http://www.legendfilms.com) if you want to see the latest colorization technology. The company just completed "It's A Wonderful Life" in high definition for Paramount Pictures and will be released on standard DVD November 9th, 2007.

The Legend Films process involves the separation of foreground and background elements in each cut of each scene (cut = a camera shot). The foreground elements (objects that move independently from the background) are colorized from a key frame (single fully designed frame) in each cut of a scene. The color (masks) is automatically transferred from one frame to the next (24 frames/sec in film) using new and very innovative pattern recognition algorithms. The backgrounds are processed separatedly as single frames. The Legend Films process elimintates all the foreground objects and creates a single frame that represents all the background elements. The single frame has all the information related to camera movement and parallax. Once the foreground elements are all colorized, the single background frame is used to automatically place the background color to all frames in the cut.

Every frame must be colorized in this manner. Optimization is a fun way to colorize a single photograph but the process cannot provide the detail and pipeling thru-put to efficiently colorize an entire feature film containing more than 150,000 to 175,000 frames.

The application of color is a one to one replacement of gray scale dynamic range with a range of color selected by a creative designer. Every object in each frame requires a color mask within which there is a spectrum of color designated for highlights, midtones and shadows.

Hope this helps.

Barry

Barry B. Sandrew, Ph.D.
Founder/COO, CTO
Legend Films, Inc.