Rotoscoping

What is Rotoscoping?

Rotoscoping is an tracing technique in which roto artist trace over footage, frame by frame, for use in live-action and animated films.The rotoscoping technique was invented by Max Fleischer, who used it in his series "Out of the Inkwell" in 1915.

Why we use Rotoscoping?

In the visual effects industry we use rotoscoping technique for creating a matte for an element on a live-action plate so it may be composited over another background.

Traditional Rotoscoping Tips

1. There is no such thing as a perfect matte. rotoscoping is an art form that takes into account the background image, the movement of the object, and the new elements to be composited in the background.
2. Try to start your shape at its most complex point in time, where it will need the most control points.
3. Break a complex shape into multiple simple shapes. If you are rotoscoping a humanoid form and an arm becomes visible, consider rotoscoping the arm as its own element, rather than adding extra points on the body that will serve no purpose when the arm is obscured.
4. Imagine you are the animator who created the shot. What would your dope sheet look like? No matter the medium, whether CG, live action or otherwise, most movements are rarely linear. They normally move in arcs; they normally accelerate in and out of stopped positions. Try and understand the mechanics behind how things are moving in your shot. This will help you to minimize keyframes.
5. Watch and study the shot before you start working. Where are the changes in directions? These will normally have keyframes. Where are the starts and stops? Are there camera moves that can be stabilized to make your work easier?
6. Don’t be afraid to trash your work and start over. Beginning roto artists often make the mistake of trying to fix a flawed approach by adding more and more keyframes. Experienced roto artists learn to quickly identify an inferior approach and are unashamed to trash their work and start over, often many, many times. It is very difficult to get a good matte without a conscious effort to keep the keyframes to a minimum.

Retopology

Retopology means remeshing of polygons according to the Production pipeline. Retopology is highly crucial for gaming, since 3d mesh is lower resize and helps in saving polygon count to support meshes in Gaming engine.Now these days the need for re-meshing arises because since now CG society loves to sculpt models digitally which are massive and ultra realistic and thus needs extra polygons. The software’s like Maya and Max are still not that much sufficient to with-stand with such a massive polygons. Software’s like Max with Graphite modeling tools and Maya with from 2014 onwards equipped with NEX-tools.Mudbox and zbrush, 3D coat and Top gun now fully supporting topology reconstruction to achieve the challenges of Next gen Gaming.

Retopology also offers an artist to work intuitively without worrying about the technical mesh and Later on can construct according to animation friendly loops and divisions to have neat and clean mesh. Retopology also reduces the chances of file crash and system instability since no more extra polygonal details are required to build mesh and one can achieve higher freedom and stability till the end stage of productions.

Introduction to UV unwrapping

The uv’s are two dimensional texture co-ordinates that reside with vertex components.Uvs are essential for applying the texture data on polygonal objects  which is otherwise not possible to apply or wrap texture on objects. Uvs are essential for Gaming also because the gaming engines are yet not technologically advanced to adapt the total geometry details mechanisims.These engines are also allowed to use certain restricted polygons, which are further upgraded or enhanced in shading with the help of realistic texture details ,which could be possible only if we do Uvs work on Models.The uvs are such an essential supportive structure to C.G industries that without UV work flow we can’t achieve the light baking process in games which is a life savior and computationally very less expensive .The other maps which are used widely in industries are :

1.Diffuse maps

2.Normal maps

3.Specular Maps

4.Occlusion Maps

5.Bump Maps

6.Height field Maps

7.Dissplacement Maps

8.Subsurface Scattering Maps

All the map workflow requires a nice uv layouts to provide realistic details to scene and objects.

Uvs are placed along with vertex and uvs are opened or viewed on 2D texture Space which have different names in different Softwares.

Uvs are created with projection techniques which are further ,if required use unfold mapping techniques ,Pelt Mapping, Peal mapping and Uv Unfolding which runs on an algorithm to calculate the uv spread either on basis of edge distance or Face area.

VIDEO EDITING

What is video editing?

The removal of unwanted footage, or parts of video, the isolation of desired footage, and the arrangement of footage in time to synthesize a new piece of footage.

The term video editing can refer to:

Linear video editing, using video tape Linear video editing is a video editing post-production process of selecting, arranging and modifying images and sound in a predetermined, ordered sequence. Regardless of whether it was captured by a video camera, tapeless camcorder, or recorded in a television studio on a video tape recorder (VTR) the content must be accessed sequentially. For the most part video editing software has replaced linear editing.

Non-linear editing system (NLE), using computers with video editing software
A non-linear editing system (NLE) is a video (NLVE) or audio editing (NLAE) digital audio workstation (DAW) system that performs non-destructive editing on source material. The name is in contrast to 20th century methods of linear video editing and film editing.

Offline editing
Offline editing is part of the post-production process of filmmaking and television production in which raw footage is copied and edited, without affecting the camera original film stock or video tape. Once the project has been completely offline edited, the original media will be assembled in the online editing stage.

Online editing
Online editing is a post-production linear video editing process that is performed in the final stage of a video production. It occurs after offline editing. For the most part online editing has been replaced byvideo editing software that operate on non-linear editing systems (NLE). High-end postproduction companies still use with NLE the Offline-Online Editing workflow