This function opens a graphics device to record the images produced in the
code expr, then uses FFmpeg to convert these images to a video.
saveVideo(
expr,
video.name = "animation.mp4",
img.name = "Rplot",
ffmpeg = ani.options("ffmpeg"),
other.opts = if (grepl("[.]mp4$", video.name)) "-pix_fmt yuv420p",
...
)the R code to draw (several) plots
the file name of the output video (e.g.
animation.mp4 or animation.avi)
the file name of the sequence of images to be generated
the command to call FFmpeg (e.g.
'C:/Software/ffmpeg/bin/ffmpeg.exe' under Windows or 'avconv' on some linux machines); note the full
path of FFmpeg can be pre-specified in ani.options('ffmpeg')
other options to be passed to ffmpeg, e.g. we can
specify the bitrate as other.opts = '-b 400k' (The default "-pix_fmt yuv420p" is a work-around for a bug in some versions of ffmpeg.)
other arguments to be passed to ani.options
An integer indicating failure (-1) or success (0) of the converting
(refer to system).
This function uses system to call FFmpeg to convert the images
to a single video. The command line used in this function is: ffmpeg
-y -r <1/interval> -i <img.name>%d.<ani.type> other.opts video.name
where interval comes from ani.options('interval'), and
ani.type is from ani.options('ani.type'). For more details on
the numerous options of FFmpeg, please see the reference.
Some linux systems may use the alternate software 'avconv' instead of 'ffmpeg'. The package will attempt to determine which command is present and set ani.options('ffmpeg') to an appropriate default value. This can be overridden by passing in the ffmpeg argument.
Examples at https://yihui.org/animation/example/savevideo/
To know more about ffmpeg, please see http://ffmpeg.org/documentation.html
Other utilities:
im.convert(),
saveGIF(),
saveHTML(),
saveLatex(),
saveSWF()