pcm: added to exp a program that resamples pcm files

exp/pcm/resample-pcm.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+
+	"bitbucket.org/ausocean/av/audio/pcm"
+)
+
+// This program accepts an input pcm file and outputs a resampled pcm file.
+// Input and output file names, to and from sample rates, channels and bit-depth can be specified as arguments.
+func main() {
+	var inPath string
+	var outPath string
+	var from int
+	var to int
+	var channels int
+	var bitDepth int
+	flag.StringVar(&inPath, "in", "data.pcm", "file path of input data")
+	flag.StringVar(&outPath, "out", "resampled.pcm", "file path of output")
+	flag.IntVar(&from, "from", 48000, "sample rate of input file")
+	flag.IntVar(&to, "to", 8000, "sample rate of output file")
+	flag.IntVar(&channels, "ch", 1, "number of channels in input file")
+	flag.IntVar(&bitDepth, "bd", 16, "bit depth of input file")
+	flag.Parse()
+
+	// Read pcm.
+	inPcm, err := ioutil.ReadFile(inPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println("Read", len(inPcm), "bytes from file", inPath)
+
+	// Resample pcm.
+	resampled, err := pcm.Resample(inPcm, from, to, channels, bitDepth)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Save resampled to file.
+	err = ioutil.WriteFile(outPath, resampled, 0644)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println("Encoded and wrote", len(resampled), "bytes to file", outPath)
+}