Tag Archive: vfx rotoscoping services

What you know about Stereo Rotoscopy?

stereo rotoscope
The areas of live action frames are traced by Roto artists where computer graphics will overlap or interact with live images. Mattes (clear areas) are created inside the frame in order to allow all elements of the scene to be layered convincingly. This helps the Compositors in combining all the various elements accurately.

The most complex shape that the subject is in can be found, to outline that first, to understand the maximum points required to be rotoscoped. Rotoscoping tools used in the compositing software have advanced and deep deviation or curvature that can be controlled to make detailed curved lines with least number of points – image segmentation, creation of mattes or masks, More often than not using rotoscoping. The essential surfaces should be isolated individually. The level of detail depends on the required conversion quality and budget.

In Rotoscopy one can trace an object using a set of tools within the compositing software for making a new alpha channel to a specific part of an image sequence or video. They can manually create this alpha through copying the tracing on top of elements inside the video and create different shapes around the object and provides animation to those shapes to sync with the movement on all the frames. The system automatically interpolates between keyframes to usually provide required result/output without having to create a new frame every time.

This is one of the steps in processing 2D to 3D Conversion movies (the process of transforming 2D film to 3D form). Once mattes/mask have been created through rotoscope it will move to next process called Depth map. It is only through this Depth map that the conversion of 3D form from 2D can be effected.

The use of blue and green screens can make the process of compositing varied elements inside a scene much more simple, (however not every shot can take advantage of blue or green screens) so rotoscoping even now plays a significant role in the entire process of visual effects.This can be a time consuming process, but the results of rotoscoping can be excellent. If more time and effort go into a roto job, the finer the results can be. It is really a very rewarding process! Every movie, TV show or music video that has special effects will require rotoscopy to enhance the picture quality and hence the Roto artists are and will remain an integral part in the VFX pipeline.

NUKE, Mocha, Fusion, Silhouette & AfterEffects are some of the software widely used in rotoscopy for best quality and ease in delivery of output.

2D to 3D Conversion is often necessary in ‘Native’ Shoots?

Many directors are under the mistaken impression that shooting in 3D is inherently superior to converting post production. The hardware and software professionals are in a sort of constant race to prove who has the upper hand in 3D. As comparisons were made as to whether the computers could achieve what the 3D cameras do – the machines won, proving that they could do incredible work with anything that were shot with 3D cameras.

A hurried 3D upgrade got Clash of the Titans’ a bad name, however as more and more successful conversions popped up like Harry Potter and the Deathly Hallows : Part 2, Thor and Captain America : The First Avenger, this stigma slowly subsided. As 2D to stereo 3D conversion techniques are becoming more sophisticated and are getting incorporated into films shot in 3D, more directors are resorting to a “hybrid” approach.

While dual cameras and a stereoscopic rig might produce better images, even films shot in native 3D nearly always have to rely on some post-production conversion. Directors now know that it is not always feasible to shoot films the way they do – on rollerblades, hanging from a helicopter or off the sides of cliffs – using these giant 3D rigs! The Cameron Pace Group, Burbank, California, is currently working in camera rigs capable of shooting in 5D, in which both 3D and 2D can be filmed simultaneously.

2D to 3D stereoscopic conversion saves a lot of time and headache since it makes the filming process easier as directors do not need to worry about getting a perfect shot during filming and it also avoids wastage of the actors’ time while setting up complex 3D rigs. It frees filmmakers to shoot their movie as they want.

Issues that may otherwise be difficult or even impossible to fix can be rectified using 2D to 3D conversion. Factors such as camera misalignment and lens mismatches can compromise a finished product. Even the slightest misalignment between the two cameras, can cause each frame to be captured from different points in time. In addition to this, the filmmaker will also have to consider the size and weight of the camera rigs and whether these can be mounted properly on the rig system intended for its use.

Some of the most common 3D shot problems that usually works its way into post production are Geometric Alignment errors, Colorimetric Alignment errors and exposure mismatches. Another issue that usually crops up is stereo window violations that can be very distracting for the viewers. Such uncomfortable violations need to be removed from the film and this can be very easily achieved using 2D to 3D conversion.

As time goes by, a film’s visual quality will not be decided by the source of the 3D – native 3D, 2D to stereoscopic 3D conversion or hybrid – as long as the various elements blend beautifully to create a 3D experience that swathes the viewers and leave them completely dumbfounded.