update the range of audio speed

app/src/main/java/com/frank/ffmpeg/activity/AudioHandleActivity.kt

@@ -216,7 +216,7 @@ class AudioHandleActivity : BaseActivity() {
             }
             R.id.btn_audio_speed//change audio speed
             -> {
-                val speed = 2.0f//from 0.5 to 2.0
+                val speed = 2.0f // funny effect, range from 0.5 to 100.0
                 val speedPath = PATH + File.separator + "speed.mp3"
                 commandLine = FFmpegUtil.changeAudioSpeed(srcFile, speedPath, speed)
             }

app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java

@@ -523,8 +523,9 @@ public class FFmpegUtil {
      * @return change speed success or not
      */
     public static String[] changeAudioSpeed(String inputPath, String outputPath, float speed) {
-        if (speed > 2 || speed < 0.5) {
+        // atempo range [0.5, 100.0]
-            throw new IllegalArgumentException("audio speed range is from 0.5 to 2");
+        if (speed > 100 || speed < 0.5) {
+            throw new IllegalArgumentException("audio speed range is from 0.5 to 100");
         }
         String speedCmd = "ffmpeg -i %s -filter_complex atempo=%.2f %s";
         speedCmd = String.format(Locale.getDefault(), speedCmd, inputPath, speed, outputPath);