Category: Code

############################################################
# transcribeZoomAudio Function
############################################################

# Zoom Audio File Processing, Function to launch transcription jobs
# This function starts an audio transcription job only == it does not output anything of use. However,
# it is useful for batch uploading audio files and starting transcription jobs for them.

# This can be done with a local file (uploads to a specified s3 bucket) or with a file that already
# exists in an s3 bucket

# example call:             transcribeZoomAudio(fileLocation="local", bucketName="my-transcription-bucket", filePath="mylocalfile.m4a", jobName="mylocalfile.m4a", languageCode="en-US")

# INPUT ARGUMENTS:
# fileLocation:             either "local" or "s3" - if local, then this function will upload the file to the specified bucket
# bucketName:               name of an existing s3 bucket that you are using for storing audio files to transcribe and finished transcriptions
# filePath:                 the path to the local file or to the s3 file (depending on whether it is "local" or "s3")
# jobName:                  the name of the transcription job for aws -- I set this to the same as the filename (without path) for convenience
# numSpeakers:              this helps AWS identify the speakers in the clip - specify how many speakers you expect
# languageCode:             the code for the language (e.g., en-US)

# OUTPUT:
# None

transcribeZoomAudio = function(fileLocation, bucketName, filePath, jobName, numSpeakers, languageCode) {
    require(paws)

    # First, if the file location is local, then upload it into the
    # designated s3 bucket
    if(fileLocation == "local") {
        localFilePath = filePath
        svc = s3()
        upload_file = file(localFilePath, "rb")
        upload_file_in = readBin(upload_file, "raw", n = file.size(localFilePath))
        svc$put_object(Body = upload_file_in, Bucket = bucketName, Key = jobName)
        filePath = paste("s3://", bucketName, "/",jobName, sep="")
        close(upload_file)
    }

    svc = transcribeservice()  
    svc$start_transcription_job(TranscriptionJobName = jobName, LanguageCode = languageCode, Media = list(MediaFileUri = filePath), OutputBucketName = bucketName, Settings = list(ShowSpeakerLabels=TRUE, MaxSpeakerLabels=numSpeakers))
}


############################################################
# processZoomAudio Function
############################################################

# Zoom Audio File Processing, process finished transcriptions
# This function parses the JSON transcription completed by AWS transcribe.
# The output is the same as the processZoomTranscript function.

# example call:             audio.out = processZoomAudio(bucketName = "my-transcription-bucket", jobName = "mylocalfile.m4a", localDir = "path-to-local-directory-for-output", speakerNames = c("Tom Smith", "Jamal Jones", "Jamika Jensen"), recordingStartDateTime = "2020-06-20 17:00:00", writeTranscript=TRUE)

# INPUT ARGUMENTS:
# bucketName:               name of the s3 bucket where the finished transcript is stored
# jobName:                  name of the transcription job (see above - i usually set this to the filename of the audio)
# localDir:                 a local directory where you can save the aws json file and also a plain text file of the transcribed text
# speakerNames:             a vector with the Zoom user names of the speakers, in the order in which they appear in the audio clip.
# recordingStartDateTime:   the date/time that the meeting recording started
# writeTranscript:          a boolean to indicate whether you want to output a plain text file of the transcript           

# OUTPUT:
# utterance_id:             an incremented numeric identifier for a marked speech utterance
# utterance_start_seconds   the number of seconds from the start of the recording (when it starts)
# utterance_start_time:     the timestamp for the start of the utterance
# utterance_end_seconds     the number of seconds from the start of the recording (when it ends)
# utterance_end_time:       the timestamp for the end of the utterance
# utterance_time_window:    the number of seconds that the utterance took
# user_name:                the name attached to the utterance
# utterance_message:        the text of the utterance
# utterance_language:       the language code for the transcript



processZoomAudio = function(bucketName, jobName, localDir, speakerNames=c(), recordingStartDateTime, writeTranscript) {
    require(paws)
    require(jsonlite)

    transcriptName = paste(jobName, "json", sep=".")
    svc = s3()
    transcript = svc$get_object(Bucket = bucketName, Key = transcriptName)
    # Write the binary component of the downloaded object to the local path
    writeBin(transcript$Body, con = paste(localDir, transcriptName, sep="/"))
    tr.json = fromJSON(paste(localDir, transcriptName, sep="/"))

    if(writeTranscript) {
        outTranscript = paste(localDir, "/", jobName, ".txt", sep="")
        write(tr.json$results$transcripts$transcript, outTranscript)
    }

    # This IDs the words as AWS broke out the different segments of speech
    for(i in 1:length(tr.json$results$speaker$segments$items)){

        res.line = tr.json$results$speaker$segments$items[[i]]
        res.line$segment_id = i
        if(i == 1) {
            res.out = res.line
        } else {
            res.out = rbind(res.out, res.line)
        }

    }

    segments = res.out 
    segment_cuts = tr.json$results$speaker$segments[,c("start_time", "speaker_label", "end_time")] 

    # Pull this apart to just get the word/punctuation with the most confidence
    # Not currently dealing with any of the alternatives that AWS could give
    for(i in 1:length(tr.json$results$items$alternatives)) {

        res.line = tr.json$results$items$alternatives[[i]]

        if(i == 1) {
            res.out = res.line
        } else {
            res.out = rbind(res.out, res.line)
        }

    }

    words = cbind(res.out, tr.json$results$items[,c("start_time", "end_time", "type")])
    words = words[words$type == "pronunciation", ]
    words_segments = merge(words, segments, by=c("start_time", "end_time"), all.x=T)

    words_segments$start_time = as.numeric(words_segments$start_time)
    words_segments$end_time = as.numeric(words_segments$end_time)

    words_segments = words_segments[order(words_segments$start_time), ]
    segment_ids = unique(words_segments$segment_id)
    i = 1


    segment_cuts$utterance_id = NA
    segment_cuts$utterance_message = NA
    for(i in 1:length(segment_ids)) {
        utterance_id = segment_ids[i]
        segment_cuts[i, "utterance_id"] = utterance_id     
        segment_cuts[i, "utterance_message"] = paste0(words_segments[words_segments$segment_id == utterance_id, "content"], collapse=" ")
    }  

    if(length(speakerNames) > 0) {
        user_names = data.frame(0:(length(speakerNames)-1), speakerNames, stringsAsFactors=F)
        names(user_names) = c("speaker_label", "user_name")
        user_names$speaker_label = paste("spk",user_names$speaker_label, sep="_")
        segment_cuts = merge(segment_cuts, user_names, by="speaker_label", all.x=T)
    }

    names(segment_cuts)[2:3] = c("utterance_start_seconds", "utterance_end_seconds")
    segment_cuts[, 2:3] = lapply(segment_cuts[, 2:3], function(x) as.numeric(x))
    segment_cuts = segment_cuts[order(segment_cuts$utterance_start_seconds), ]

    # Now turn these into actual datetime values
    recordingStartDateTime = as.POSIXct(recordingStartDateTime)
    segment_cuts$utterance_start_time = recordingStartDateTime + segment_cuts$utterance_start_seconds
    segment_cuts$utterance_end_time = recordingStartDateTime + segment_cuts$utterance_end_seconds

    # Create a time window (in seconds) for the utterances -- how long is each in seconds
    segment_cuts$utterance_time_window = as.numeric(difftime(segment_cuts$utterance_end_time, segment_cuts$utterance_start_time, units="secs"))

    # Prepare the output file
    res.out = segment_cuts[, c("utterance_id", "utterance_start_seconds", "utterance_start_time", "utterance_end_seconds", "utterance_end_time", "utterance_time_window", "user_name", "utterance_message")]

    # Mark as unidentified any user with a blank username
    res.out$user_name = ifelse(res.out$user_name == "" | is.na(res.out$user_name), "UNIDENTIFIED", res.out$user_name)      

    # Add the language code
    res.out$utterance_language = languageCode

    return(res.out)    

}