Batch process video files, breaking them into stills

#' This helper calls grabVideoStills, which function currently relies on the av package and 'ffmpeg' to split a video file into images. This function will save the images to the director specified by the user.

batchGrabVideoStills(
  batchInfo,
  imageDir = NULL,
  overWriteDir = FALSE,
  sampleWindow
)

Arguments

batchInfo

the batchInfo data.frame that is output from batchProcessZoomOutput
imageDir

the directory where you want the function to write the extracted image files
overWriteDir

logical indicating whether you want to overwrite imageDir if it exists
sampleWindow

an integer indicating how frequently you want to sample images in number of seconds.

Value

a data.frame that gives information about the batch. Each record corresponds to one video, with:

  • batchMeetingId - the meeting identifier

  • videoExists - boolean indicating whether the video file was there

  • imageDir - path to the directory where video images are saved

  • sampleWindow - integer with the sampleWindow requested

  • numFramesExtracted - the number of image files that were saved

Examples

vidBatchInfo = batchGrabVideoStills(batchInfo=sample_batch_info,
imageDir=tempdir(), overWriteDir=TRUE, sampleWindow=2)

#> 
  |                                                                            
  |                                                                      |   0%
#> Processing meeting001_video.mp4 using ffmpeg. Note that processing videos can be time intensive for long duration videos.
#> 
  |                                                                            
  |===================================                                   |  50%
  |                                                                            
  |======================================================================| 100%
#> Processing meeting003_video.mp4 using ffmpeg. Note that processing videos can be time intensive for long duration videos.
#> 
if (FALSE) {
vidBatchInfo = batchGrabVideoStills(batchInfo=zoomOut$batchInfo,
imageDir="~/Documents/myMeetings/videoImages", overWriteDir=TRUE,  sampleWindow=600)
}