Image-based animation

Hello students, welcome to Kwickprep. Can a simple photo of a cricket ball fly across the screen? Yes, it can. Today we will learn image-based animation in Synfig Studio. We will import pictures, move them with waypoints, and build a flipbook from many images.

First, let us understand animation itself. Animation is made of many still pictures, and each picture is called a frame. These frames are shown very quickly, one after another. Our eyes and brain join them, so we see smooth movement. The number of frames shown in one second is the frame rate, written as fps. Synfig uses twenty four frames per second by default.

In image-based animation, we use ready pictures instead of drawing shapes. There are two common ways. In the first way, we take one image and change its position, size or angle over time. In the second way, we show many different images one after another, like a flipbook. In the first way, Synfig calculates the frames in between, so we do less work.

Synfig can import common image files. PNG files can have a transparent background, so a ball will not carry a white box around it. JPEG files are good for photographs. GIF files suit simple graphics with few colours. BMP files are plain bitmaps, which are large in size.

Now let us bring a picture into Synfig. Open the File menu and choose Import. You can also press control and the letter I together. Select the picture file and click the Import button. The image appears on the canvas, and a new layer appears in the Layers panel.

Before we animate, learn four words. The canvas is the working area where we build the scene. A layer is one object, like one transparent sheet placed on top of others. The time track is the timeline that shows the seconds of the scene. A waypoint is a small marker that stores a value, like a position, at one moment in time.

Synfig has a special switch called Animation mode. Click the Animation mode button at the bottom right of the canvas. The canvas gets a red border, so you know it is on. Now every change you make at a time is saved as a waypoint. When it is off, a change applies to the whole scene and nothing moves.

Let us animate a cricket ball from left to right. First, import the file ball dot PNG. Then switch Animation mode on. At zero seconds, place the ball on the left side. Move the time cursor to two seconds, and drag the ball to the right side. Synfig creates two waypoints and fills the frames between them. Finally, press Play and check the movement.

Many properties of an image layer can change over time. Drag the image to change its position, and it moves. Drag a corner handle to change its size, and it grows or shrinks. Add a Rotate layer above it and change the angle, and it spins. Change the Amount, which is the opacity, from one to zero, and the image fades out.

Here is an important idea for exams. You set only the key positions, like the start and the end. Synfig calculates all the frames between them by itself. Making these in-between frames is called tweening. The waypoint style, such as linear or ease in and out, decides whether the movement is steady or gently slows down.

Pause and predict. There is a waypoint at zero seconds with the ball on the left. There is another waypoint at four seconds with the ball on the right. The frame rate is twenty four frames per second. Where is the ball at two seconds? With linear waypoints, it is exactly in the middle, because two seconds is halfway.

The second way is the flipbook, also called an image sequence. Draw each pose of a character as a separate picture. Name the files in order, such as walk one, walk two and walk three. Each image is shown for a few frames, then the next image takes its place. When the images repeat in a loop, the character seems to walk or run.

Synfig makes the flipbook easy. Select all the images in the Import window and import them together. Synfig places them inside a Switch group layer. A Switch group shows only one of its inner layers at a time, called the active layer. In Animation mode, change the active layer at different times, and the pictures swap like pages.

Here are some tips for clean work. Use PNG images with a transparent background, so no white boxes appear. Keep all images of a sequence the same size, or the character will jump. Save your project often, and Synfig saves it as a dot sifz file. Always preview the animation before the final render.

Let us revise what we learned today. Animation is many frames shown quickly, and speed is measured in frames per second. We import images using File, Import, or control I. With Animation mode on, every change becomes a waypoint. Synfig fills the frames between waypoints, and this is called tweening. For a flipbook, many images go into a Switch group and swap over time.