writeAnimation

Save animation as video file

Syntax

writeAnimation(filename)

writeAnimation(fig,filename)

writeAnimation(___,Name,Value)

writeAnimation(vidObj)

writeAnimation(fig,vidObj)

Description

writeAnimation(filename) writes animation objects in the current figure to a GIF or AVI video file. The animation objects must be created using the fanimator function. The extension of filename sets the video format, and must be either '.gif' or '.avi'.

• If you do not specify the file extension, then writeAnimation chooses the '.avi' extension by default.

• If you specify any other file extension, such as '.mp4' or '.mpg', then writeAnimation returns an error message.

writeAnimation(fig,filename) writes animation objects in the figure fig to a GIF or AVI video file.

writeAnimation(___,Name,Value) writes animation objects with the specified Name,Value pair arguments. Use this option with any of the input argument combinations in the previous syntaxes. You can set the name-value pair settings to specify the properties of a GIF or AVI video file.

writeAnimation(vidObj) writes animation objects in the current figure to a VideoWriter object. This syntax provides the option to save animation objects in another video file format, such as 'MPEG-4' or 'Uncompressed AVI'.

writeAnimation(fig,vidObj) writes animation objects in the figure fig to a VideoWriter object.

If you save an animation as a VideoWriter object, then the properties of the output video file follow the properties of the VideoWriter object.

Examples

Save Animation of Moving Circle as GIF File

Create a moving circle animation object and save it as a GIF file.

Create two symbolic variables, t and x. The variable t defines the time parameter of the animation. Use t to set the center of the circle at (t,1) and x to parameterize the perimeter of the circle within the range [-pi pi]. Create the circle animation object using fanimator. Set the x-axis and y-axis to be equal length.

syms t x
fanimator(@fplot,cos(x)+t,sin(x)+1,[-pi pi])
axis equal

Enter the command playAnimation to play the animation. Save the animation as a GIF video file named 'wheel.gif'.

writeAnimation('wheel.gif')

Save Animation of Moving Circle as MPEG-4 File

Create a moving circle animation object and save it as an MPEG-4 file.

First, create two symbolic variables, t and x. The variable t defines the time parameter of the animation. Use t to set the center of the circle at (t,1) and x to parameterize the perimeter of the circle within the range [-pi pi]. Create the circle animation object using fanimator. Set the x-axis and y-axis to be equal length.

syms t x
fanimator(@fplot,cos(x)+t,sin(x)+1,[-pi pi])
axis equal

Enter the command playAnimation to play the animation.

Next, save the animation as an MPEG-4 file. Create a video object that saves to a file named 'myFile' by using the VideoWriter function. Specify the video file format as 'MPEG-4'. Open the video file, use writeAnimation to save the circle animation object, and close the video file.

vidObj = VideoWriter('myFile','MPEG-4');
open(vidObj)
writeAnimation(vidObj)
close(vidObj)

Save Animation as Looping GIF File

Create a circle animation object and save it as a GIF file that plays a specified number of loops.

First, create two symbolic variables, t and x. The variable t defines the time parameter of the animation. Create a figure window for the animation.

syms t x
fig = figure;

Create the circle animation object using fanimator. Use t to set the center of the circle at (t,1) and x to parameterize the perimeter of the circle within the range [-pi pi]. Set the x-axis and y-axis to be equal length.

syms t x
fanimator(@fplot,cos(x)+t,sin(x)+1,[-pi pi])
axis equal

Enter the command playAnimation to play the animation.

Next, save the animation in the figure fig as a GIF file named 'loop.gif' by using the writeAnimation function. The writeAnimation function always plays the animation once in a MATLAB^® figure window before saving the animation. When saving the animation as a GIF file, the created GIF file plays the animation once and repeats the number of loops as specified. For this example, set 'LoopCount' to 1. The GIF file plays the animation twice.

writeAnimation(fig,'loop.gif','LoopCount',1)

Note that to properly show the number of loops in a GIF video file, you must open the file in an application with GIF decoder.

Input Arguments

filename — Video filename

string | character vector

Video filename, specified as a string scalar or character vector. The extension of filename sets the video format, and must be either '.gif' or '.avi'. You must have permission to write the file.

• If you do not specify the file extension, then writeAnimation uses '.avi' by default.

• If filename already exists, then writeAnimation overwrites the file.

• If filename does not include a full path, then the function saves the animation to the current folder.

vidObj — Video object

VideoWriter object

Video object, specified as a VideoWriter object. The VideoWriter object provides the option to control the output video format when you save animation objects. For more information about VideoWriter object in MATLAB, see VideoWriter.

fig — Target figure

Figure object

Target figure, specified as a Figure object. For more information about Figure objects, see figure.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: 'FrameRate',15,'LoopCount',2

AnimationRange — Range of animation time parameter

[0 10] (default) | two-element row vector

Range of the animation time parameter, specified as a two-element row vector. The two elements must be real values that are increasing.

Example: [-2 4.5]

FrameRate — Frame rate

10 (default) | positive value

Frame rate, specified as a positive value. The frame rate defines the number of frames per unit time when you write animation objects to a video file.

Example: 30

Backwards — Backward option

logical 0 (false) (default) | logical value

Backward option, specified as a logical value (boolean). If you specify true, then the function saves the animation backward or in reverse order.

Example: true

LoopCount — Animation loop count

0 (default) | nonnegative integer (from 0 to 65535) | Inf

Animation loop count, specified as a nonnegative integer (from 0 to 65535) or Inf. This value sets the number of repeated animation loops in a GIF file. Setting this value has no effect if you use a video file format other than GIF.

• If you use the default value of 0, then the GIF file plays the animation once.

• If you set 'LoopCount' to an integer n, then the GIF file plays the animation once plus n repeats (a total of n+1 times).

• To repeat the animation infinitely, use the Inf value.

Example: 1

Version History

Introduced in R2019a