ari_stitch: Create a video from images and audio

In ari: Automated R Instructor

Description

Given a vector of paths to images (preferably .jpgs or .pngs) and a flat list of Waves of equal length this function will create an .mp4 video file where each image is shown with its corresponding audio. Take a look at the readWave function if you want to import your audio files into R. Please be sure that all images have the same dimensions.

Usage

ari_stitch(
  images,
  audio,
  output = tempfile(fileext = ".mp4"),
  verbose = FALSE,
  cleanup = TRUE,
  ffmpeg_opts = "",
  divisible_height = TRUE,
  audio_codec = get_audio_codec(),
  video_codec = get_video_codec(),
  video_sync_method = "2",
  audio_bitrate = NULL,
  video_bitrate = NULL,
  pixel_format = "yuv420p",
  fast_start = TRUE,
  deinterlace = TRUE,
  stereo_audio = TRUE
)

Arguments

images	A vector of paths to images.
audio	A list of Waves from tuneR.
output	A path to the video file which will be created.
verbose	print diagnostic messages. If > 1, then more are printed
cleanup	If TRUE, interim files are deleted
ffmpeg_opts	additional options to send to ffmpeg. This is an advanced option, use at your own risk
divisible_height	Make height divisible by 2, which may be required if getting "height not divisible by 2" error.
audio_codec	The audio encoder for the splicing. If this fails, try copy.
video_codec	The video encoder for the splicing. If this fails, see ffmpeg -codecs
video_sync_method	Video sync method. Should be "auto" or '"vfr"' or a numeric. See https://ffmpeg.org/ffmpeg.html.
audio_bitrate	Bit rate for audio. Passed to -b:a.
video_bitrate	Bit rate for video. Passed to -b:v.
pixel_format	pixel format to encode for 'ffmpeg'.
fast_start	Adding 'faststart' flags for YouTube and other sites, see https://trac.ffmpeg.org/wiki/Encode/YouTube
deinterlace	should the video be de-interlaced, see https://ffmpeg.org/ffmpeg-filters.html, generally for YouTube
stereo_audio	should the audio be forced to stereo, corresponds to '-ac 2'

Details

This function uses FFmpeg which you should be sure is installed before using this function. If running Sys.which("ffmpeg") in your R console returns an empty string after installing FFmpeg then you should set the path to FFmpeg on you computer to an environmental variable using Sys.setenv(ffmpeg = "path/to/ffmpeg"). The environmental variable will always override the result of Sys.which("ffmpeg").

Value

A logical value, with the attribute outfile for the output file.

Examples

## Not run: 
if (ffmpeg_version_sufficient()) {
result = ari_stitch(
ari_example(c("mab1.png", "mab2.png")),
list(tuneR::noise(), tuneR::noise()))
} 

## End(Not run)

ari documentation built on Feb. 9, 2020, 1:07 a.m.