Convert MP3 Files to WAV in Swift

The WAV format was developed by IBM and Microsoft, and is the main format utilized by Windows for raw and often uncompressed audio. Due to the high resolution of the format, it consistently delivers high quality audio; this is especially helpful in professional audio editing environments. If you need to convert a file to the WAV format, the following tutorial will demonstrate how to use an API in Swift to convert an MP3 or other audio format to WAV with very little effort.

Let’s start the process by inputting the target file and the API key into the following code:

import Foundation
#if canImport(FoundationNetworking)
import FoundationNetworking
var semaphore = DispatchSemaphore (value: 0)let parameters = [
"key": "inputFile",
"src": "/path/to/file",
"type": "file"
]] as [[String : Any]]
let boundary = "Boundary-\(UUID().uuidString)"
var body = ""
var error: Error? = nil
for param in parameters {
if param["disabled"] == nil {
let paramName = param["key"]!
body += "--\(boundary)\r\n"
body += "Content-Disposition:form-data; name=\"\(paramName)\""
if param["contentType"] != nil {
body += "\r\nContent-Type: \(param["contentType"] as! String)"
let paramType = param["type"] as! String
if paramType == "text" {
let paramValue = param["value"] as! String
body += "\r\n\r\n\(paramValue)\r\n"
} else {
let paramSrc = param["src"] as! String
let fileData = try NSData(contentsOfFile:paramSrc, options:[]) as Data
let fileContent = String(data: fileData, encoding: .utf8)!
body += "; filename=\"\(paramSrc)\"\r\n"
+ "Content-Type: \"content-type header\"\r\n\r\n\(fileContent)\r\n"
body += "--\(boundary)--\r\n";
let postData = .utf8)
var request = URLRequest(url: URL(string: "")!,timeoutInterval: Double.infinity)
request.addValue("<string>", forHTTPHeaderField: "fileUrl")
request.addValue("<number>", forHTTPHeaderField: "sampleRate")
request.addValue("multipart/form-data", forHTTPHeaderField: "Content-Type")
request.addValue("YOUR-API-KEY-HERE", forHTTPHeaderField: "Apikey")
request.addValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
request.httpMethod = "POST"
request.httpBody = postData
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data else {
print(String(describing: error))
print(String(data: data, encoding: .utf8)!)

It’s important to note that the operation uses 1 API call per 10 MB of file size, as well as 1 API call per additional minute of processing time over 5 minutes (max 25 min). To retrieve your free API key and gain access to 800 monthly calls across our API library, simply head to Cloudmersive website.

There’s an API for that. Cloudmersive is a leader in Highly Scalable Cloud APIs.