Record Video from Graphics Device
Runs the expression and captures all plots into a video. The av_spectrogram_video function is a wrapper that plots data from read_audio_fft with a moving bar and background audio.
av_capture_graphics( expr, output = "output.mp4", width = 720, height = 480, framerate = 1, vfilter = "null", audio = NULL, verbose = TRUE, ... ) av_spectrogram_video( audio, output = "output.mp4", framerate = 25, verbose = TRUE, ... )
expr |
an R expression that generates the graphics to capture |
output |
name of the output file. File extension must correspond to a known
container format such as |
width |
width in pixels of the graphics device |
height |
height in pixels of the graphics device |
framerate |
video framerate in frames per seconds. This is the input fps, the output fps may be different if you specify a filter that modifies speed or interpolates frames. |
vfilter |
a string defining an ffmpeg filter graph. This is the same parameter
as the |
audio |
path to media file with audio stream |
verbose |
emit some output and a progress meter counting processed images. Must
be |
... |
extra graphics parameters passed to |
library(gapminder)
library(ggplot2)
makeplot <- function(){
datalist <- split(gapminder, gapminder$year)
lapply(datalist, function(data){
p <- ggplot(data, aes(gdpPercap, lifeExp, size = pop, color = continent)) +
scale_size("population", limits = range(gapminder$pop)) + geom_point() + ylim(20, 90) +
scale_x_log10(limits = range(gapminder$gdpPercap)) + ggtitle(data$year) + theme_classic()
print(p)
})
}
# Play 1 plot per sec, and use an interpolation filter to convert into 10 fps
video_file <- file.path(tempdir(), 'output.mp4')
av_capture_graphics(makeplot(), video_file, 1280, 720, res = 144, vfilter = 'framerate=fps=10')
av::av_media_info(video_file)
# utils::browseURL(video_file)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.