Add verbose argument to av_video_images

[gavril0]

I suggest adding a verbose argument with interactive() or TRUE as default value to av_video_images and transmit it to ave_encod_video inside the function.

av_video_images <- function (video, destdir = tempfile(), format = "jpg", fps = NULL, 
    trim = NULL, verbose=interactive() ) 
{
    stopifnot(length(video) == 1)
    filter_fps <- if (length(fps)) 
        paste0("fps=fps=", fps)
    filter_trim <- if (length(trim)) 
        paste0("trim=", trim)
    vfilter <- paste(c(filter_trim, filter_fps), collapse = ", ")
    if (vfilter == "") 
        vfilter <- "null"
    framerate <- av_media_info(video)$video$framerate
    dir.create(destdir)
    codec <- switch(format, jpeg = "mjpeg", jpg = "mjpeg", format)
    output <- file.path(destdir, paste0("image_%6d.", format))
    av_encode_video(input = video, output = output, framerate = framerate, 
        codec = codec, vfilter = vfilter, verbose=verbose)
    list.files(destdir, pattern = paste0("image_\\d{6}.", format), 
        full.names = TRUE)
}