sweptsine

DESCRIPTION

@@ -15,7 +15,7 @@ Imports:
 License: GPL-3
 Encoding: UTF-8
 LazyData: true
-RoxygenNote: 7.0.2
+RoxygenNote: 7.1.0
 Language: en-GB
 Suggests: 
   testthat,

NAMESPACE

@@ -44,6 +44,7 @@ export(soundSpeed_cramer1993)
 export(specStats)
 export(ste)
 export(subtractSpectra)
+export(sweptsine)
 export(tSamples)
 export(validateIsWave)
 export(windowing)
@@ -62,6 +63,7 @@ importFrom(graphics,title)
 importFrom(jsonlite,fromJSON)
 importFrom(seewave,duration)
 importFrom(seewave,meanspec)
+importFrom(seewave,savewav)
 importFrom(seewave,sfm)
 importFrom(seewave,sh)
 importFrom(stats,approx)

R/googleSpeech.R

@@ -6,7 +6,7 @@
 #' @param bucket Storage bucket on Google Cloud for larger files
 #' @param ... Additional arguments to pass to gl_speech()
 #' @importFrom tuneR readWave
-#' @importFrom seewave duration
+#' @importFrom seewave duration savewav
 #' @export
 #' @return A gs_transcribe object containing details of the transcription
 #' @examples
@@ -16,10 +16,17 @@
 #'
 gs_transcribe <- function(filename, bucket=NULL,...) {
   if (package.installed("googleCloudStorageR") & package.installed("googleLanguageR")) {
-    max_d <- 3 #Max duration for objects not in Cloud Storage
+    max_d <- 3000 #Max duration for objects not in Cloud Storage
+    max_samp_rate = 48000
     wave <- readWave(filename)
+    if (wave@samp.rate > max_samp_rate) {
+      print("Downsampling to 48kHz")
+      savewav(wave, f=max_samp_rate, filename="temp.wav", extensible = FALSE)
+      filename <- "temp.wav"
+      wave@samp.rate <- max_samp_rate
+    }
     if (duration(wave) < max_d) {
-      return(gs_transcribe_execute(filename,...))
+      return(gs_transcribe_execute(filename, ...))
     } else {
       #Upload
       upload_try <- googleCloudStorageR::gcs_upload(filename, bucket=bucket, name="temp")
@@ -31,16 +38,17 @@ gs_transcribe <- function(filename, bucket=NULL,...) {
   }
 }
 
-gs_transcribe_execute <- function(object,...) {
+gs_transcribe_execute <- function(object, ...) {
+  object
   async <- googleLanguageR::gl_speech(object, asynch=TRUE,...)
-  result <- googleLanguageR::gl_speech_op(async)
+  async <- googleLanguageR::gl_speech_op(async)
   tries <- 1
-  while (is.null(result$transcript)) {
+  while (TRUE) {
     Sys.sleep(exponential_backoff(tries))
-    result <- googleLanguageR::gl_speech_op(async)
+    async <- googleLanguageR::gl_speech_op(async)
     tries <- tries + 1
   }
-  return(gs_preprocess_transcript(result))
+  return(gs_preprocess_transcript(async))
 }
 
 gs_preprocess_transcript <- function(transcript, offset=0) {

R/sweptsine.R

@@ -0,0 +1,40 @@
+#' Generate a frequency-swept sine wave
+#'
+#' Generates a frequency swept sine wave and returns it as a Wave object or vector.
+#'
+#' @param f0 Start frequency
+#' @param f1 End frequency
+#' @param sweep.time Duration of swept wave
+#' @param A Amplitude of wave
+#' @param samp.rate Sample rate of swept wave
+#' @param output "wave" for a Wave object, or "vector"
+#' @param ... Additional arguments to pass to data2Wave
+#' @export
+#' @return A swept wave object of the type specified in output.
+#' @examples
+#' sweptsine()
+#'
+sweptsine <- function(f0=100, f1=2500, sweep.time=1, A=1, samp.rate=44100, output="wave", ...) {
+  f <- f0
+  phi <- 0 #Phase accumulator
+  delta <- 2 * pi * f / samp.rate
+  f_delta <- (f1 - f0) / (samp.rate * sweep.time)
+
+  w <- vector(mode="numeric", length=samp.rate*sweep.time)
+
+  i <- 1
+  while (i < samp.rate*sweep.time) {
+    w[i] <- A * sin(phi)
+    phi <- phi + delta
+    f <- f + f_delta
+    delta <- 2 * pi * f / samp.rate
+    i <- i+1
+  }
+  if (output == "vector") {
+    return(w)
+  }
+  if (output == "wave") {
+    return(data2Wave(w, samp.rate=samp.rate, ...))
+  }
+
+}