Layering in graphic design
One of the first windows to pop up automatically, when I first started using Adobe Photoshop back in 2013, was the Layers one. Albeit I was dabbling around with it for making memes, it was one of the first things I played around with.
A few days back I completed an animation internship under Apsolutio and the knowledge of layering helped me in creating quite a number of 2D animated videos with my team members.
This stands as a testament to the importance of layers, and layering, in not only image editing, but also in video editing and graphic designing as a whole. This important aspect of graphic designing is explored in this Medium blog…
Pre-Requisites
Vector and Raster Images
A fundamental concept in computer graphics is the distinction between raster and vector images. Most everyday computer users might be familiar with the extensions of image and video files, but what happens under the hood of that car is a mystery for them. Most of the work done in the early stages of life (school projects) involve raster images. I first discovered vector images while surfing Wikipedia. I downloaded this picture of an equation and it was saved as an SVG file. The magical thing I realised was that the image opened up in a full window around ten times the size shown in a small box in Wikipedia — and there were no cracks or jagged edges. Nothing!
SVG (Scalable Vector Graphics) is one of the vector image formats, others being EPS (Encapsulated PostScript), PDF (Portable Document Format) or AI (Adobe Illustrator Artwork). You might be familiar with the common raster types: JPG/JPEG, PNG, GIF (the moving ones), BMP (the default for older versions of MS Paint).
Zooming in on the raster files will cause pixelation to occur at some point, whatever the resolution may be. This is because raster images are basically rectangular grids, where each space is filled with some colour in the RGB (Red Green Blue) format.
Why RGB? This is because any colour can be represented as portions of Red, Green and Blue mixed together. The extremes of this system are Black (absence of any colour, i.e. Red=Blue=Green=0%) and White (all colours combined, i.e. Red=Blue=Green=100%). The cube below is called the RGB Colour Model or RGB Cube and gives a visual idea of the aforesaid…
Vector images, however, are not your everyday paintings and colour grids. They are lines of code. These lines of code define points on a plane, connected by paths — straight lines or curves or polygons… bearing resemblance to vectors in Mathematics. The colour, shape, thickness and other properties are all defined within this block of code. An example of such code (image here) is given below…
The more complex the image, the more information the code contains. The most popular vector graphics designer is Adobe Illustrator, followed closely by Inkscape (FOSS). When it comes to raster images, Adobe Photoshop has remained the undefeated champion for a long time, with GIMP (FOSS) coming a close second.
Image to Video
‘Who Framed Roger Rabbit’ was a 1988 movie, seamlessly combining live-action and 2D animation in the same screen. The second word is the key to understand how photos and videos are linked.
Videos are made up of frames — which are basically images. These images are linked together based on one intangible aspect — time. If you view the description of any video in your media player, there is a quantity called the frame rate. Usually, for film, it is around 24 fps (frames per second). This means that there are around 24 images being displayed back to back in one second. That’s it. Millions of images pieced together with audio in the background — and you get your movie.
(Apart from the conventional video editor software, VLC Media Player (VideoLan, FOSS) also allows you to view a video in a frame-by-frame fashion. Go check it out!)
The Importance of Layering
The importance of layering lies in its application. Let’s take the case of my internship experience as an example. We had to use an existing vector file which had the company’s mascot, edit it, and create a whole animated video around it explaining a financial management app (Finakya). The video had buildings, trees, other characters, even a smartphone to explain the app. With so many components inside a fixed canvas and multiple people working with them to achieve a certain end result, the problem has to be broken down into simpler parts (divide and ru… conquer).
When we place a video in any video editing app, we are usually given a horizontal workspace. The concept of layering, however, is vertical in nature. It is not concerned with what comes next or what came before. All that matters is who’s on top and who’s down below. Let’s not visualize much…
There are two components in the video — the image (Video Track 2) and the underlying video (Video Track 1, along with its audio in Audio Track 1). This is a simple two-part example — easy to merge and manage. Imagine you have thousands of such components. Managing them will not be as easy as this.
An example of a layered photoshop document is given below…
Therefore the concept of layering is the same for image or videos. The only factor which creeps in when videos are concerned is time. The work is done vertically via layers and horizontally via frames.
Adobe After Effects (AE) is one such video-editing app where the vertical arrangement gets precedence over the horizontal (Adobe Premiere Pro exists for that purpose). Most of the animation work during the aforementioned internship was done in AE.
Layering and Masking
Layer masking is an editing concept that goes hand in hand with basic layering, most of which is discussed above. Masking is close to its literal sense, as it masks a layer with respect to another layer, some effect applied to that layer (adjustment layer), etc.
Basic Layering
It is the superimposition of one layer on another and so on… This is what we have discussed in the screenshots supplied. Some other examples which are of use in image editing are also given below…
Layer Masking
I came about this concept while learning how to put text behind objects in video and the term popped up in a YouTube video. Like any other video editing concept, its roots lie in image editing — it is based on layer masks. In the internship project, we had to use masking in cases where the screen to be shown on the smartphone screen was too long to fit (as shown).
We had to apply a mask along the screen borders such that every layer on top of the smartphone layer falls inside the screen and doesn’t spill. Since we were dealing with app screen animation inside the smartphone, this concept was used multiple times and made things easier for the team. Let us see how masking generally occurs in graphic editing.
The layer masking does the following: the black part of the image is hidden and the white part is not, i.e. the black part contains nothing of the foreground (the layer where the mask is applied), while the white part of the foreground is visible. The final result shows this masked result. Instead of black and white, the two extremes, shades of grey can also be used to create a mask.
Layering in video editing is a horizontal expansion from this concept, as discussed before. It is a paramount concept in graphic editing as a whole, with its ripples felt in mainstream film-making too. A proper grasp on it will help with present and future projects dealing with computer graphics.
