VideoGenerator

VideoGenerator[model]

generates one second of video of a given model.

VideoGenerator[model,dur]

generates a video of duration dur.

Details and Options

  • VideoGenerator can be used to generate video objects algorithmically. It is typically used for creating video of a time-varying plot, a rotating 3D object, etc.
  • Possible settings for model include:
  • imagespecmodel to create images for the video track
    <|"Image"imagespec,"Audio"audiospec|>models to create images and audio samples for video and audio tracks
  • The imagespec can be any of the following:
  • imageuses image in the first track
    {image1,image2,…}uses the sequence of imagei in the first track
    {{im11,im12,…},{im21,im22,…},…}uses the sequence of {imi1,imi2,…} in the ^(th) track
    imagefunca function imagefunc of time that creates one or multiple images
  • If imagefunc returns a list of images, the image at position i is assumed to be the frame for the ^(th) video track.
  • The audiospec can be any of the following:
  • audiouses audio in the first track
    {audio1,audio2,…}uses the sequence of audioi in the first track
    {{a11,a12,…},{a21,a22,…},…}uses the sequence of {ai1,ai2,…} in the ^(th) track
    audiofunca function audiofunc of time that creates a list or matrix of audio samples
  • If audiofunc returns a matrix of audio values, the list at position i is assumed to be the data for the ^(th) audio track.
  • The duration specification dur can be any of the following:
  • durtime given in seconds
    Quantity[dur,"Seconds"]time given in seconds or any compatible unit
    Quantity[n,"Frames"]time given as a number of frames
  • To generate frames in parallel, use Parallelize[VideoGenerator[…]]. »
  • By default, VideoGenerator places the new video under the "Video" directory in $WolframDocumentsDirectory.
  • The following options are supported:
  • AudioEncodingAutomaticaudio encoding to use
    BitRateAutomaticapproximate bit rate to use
    CompressionLevelAutomaticcompression level to use
    FrameRate30the frame rate to use
    GeneratedAssetFormatAutomaticthe file format of the result
    GeneratedAssetLocation$GeneratedAssetLocationthe location of the result
    OverwriteTargetFalsewhether to overwrite an existing file
    RasterSizeAutomaticthe raster size used to rasterize expressions
    SampleRateAutomaticthe audio sample rate to use
    VideoEncodingAutomaticvideo encoding to use

Examples

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Basic Examples  (2)

Generate a video of a varying plot:

Generate video from rotating 3D graphics:

Scope  (8)

Video from Images  (3)

Create a two-second-long video from a single image:

Specify the number of frames to generate:

Verify the number of frames in the result:

Create a video from a list of images:

Show time series of frame color values:

Video from a Function  (3)

Create a video from a rotating image:

Show a few frames of the generated video:

Use a function to generate frames:

The function takes the time as input and rasterizes it to an Image:

Use a function to generate two video tracks:

The function generates blurred frames in the first track with increasing radius:

The function generates quantized images with increasing colors in the second track:

Video with Audio  (2)

Create a video with an audio track:

The image function takes the time as input and outputs an Image:

The audio function takes the time as input and uses it to control the frequency of a triangle wave:

Options  (10)

AudioEncoding  (1)

Use the AudioEncoding option to specify the audio encoding to be used:

CompressionLevel  (1)

Use the CompressionLevel option to control the file size of the result:

Compare file sizes using different compression levels:

FrameRate  (1)

The default frame rate is 30 frames per second:

Specify the frame rate to use:

GeneratedAssetLocation  (2)

Assets are automatically generated in the "Video" folder within $WolframDocumentsDirectory:

Specify the location of the asset created by VideoGenerator:

Use a LocalObject as the asset for the resulting Video object:

OverwriteTarget  (1)

By default, if a file already exists it is not overwritten:

Overwrite an existing file by specifying OverwriteTargetTrue:

RasterSize  (1)

By default, if the video tracks specification produces a Graphics object, the result is rasterized:

Use the RasterSize option to control the rasterization:

If the video tracks specification produces an Image, specifying the RasterSize option will resize the result:

SampleRate  (2)

By default, if the audio tracks specification is an Audio object, the sample rate will be preserved:

Use the SampleRate option to resample the audio input:

If the audio tracks specification is a function, the default sample is Hz:

Use the SampleRate option to control the sample rate of the result:

VideoEncoding  (1)

Use the VideoEncoding option to specify the video encoding to be used:

Applications  (6)

Create a video by adding a still image to an audio signal:

Generate a video of rotating 3D graphics:

Generate a video by moving the viewpoint around a 3D object:

Visualize the viewpoint trajectory:

Generate the Video:

Create a Video object displaying the evolution of a cellular automaton:

Create a Video object displaying a ball bouncing down steps.

First, solve the differential equation governing the motion of the ball:

Precompute a "staircase" background:

Display the evolution of the ball's position over the staircase:

Create a video showing the travel directions from Champaign to Chicago:

Extract the points forming the path:

Create the video:

Properties & Relations  (3)

Parallelize an expensive frame generation to speed up the computation:

Use Animate to create an animation in a notebook:

VideoGenerator can achieve the same results but without displaying any controls:

The result is also more easily shareable outside a notebook, since it creates a video file.

Separately generated video and audio objects can be combined using VideoCombine.

Generate a video with no audio:

Generate an audio sample:

Combine the two using VideoCombine:

Possible Issues  (1)

Parallelize an expensive frame generation to speed up the computation:

Parallelization does not benefit functions that are already fast and multi-threaded:

Wolfram Research (2020), VideoGenerator, Wolfram Language function, https://reference.wolfram.com/language/ref/VideoGenerator.html (updated 2021).

Text

Wolfram Research (2020), VideoGenerator, Wolfram Language function, https://reference.wolfram.com/language/ref/VideoGenerator.html (updated 2021).

CMS

Wolfram Language. 2020. "VideoGenerator." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2021. https://reference.wolfram.com/language/ref/VideoGenerator.html.

APA

Wolfram Language. (2020). VideoGenerator. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/VideoGenerator.html

BibTeX

@misc{reference.wolfram_2022_videogenerator, author="Wolfram Research", title="{VideoGenerator}", year="2021", howpublished="\url{https://reference.wolfram.com/language/ref/VideoGenerator.html}", note=[Accessed: 06-July-2022 ]}

BibLaTeX

@online{reference.wolfram_2022_videogenerator, organization={Wolfram Research}, title={VideoGenerator}, year={2021}, url={https://reference.wolfram.com/language/ref/VideoGenerator.html}, note=[Accessed: 06-July-2022 ]}