From ace10310954a984c2d7b4e204146b25d1691b430 Mon Sep 17 00:00:00 2001
From: xufuji456 <839789740@qq.com>
Date: Tue, 8 Jun 2021 08:59:27 +0800
Subject: [PATCH] update the range of audio speed

---
 .../java/com/frank/ffmpeg/activity/AudioHandleActivity.kt    | 2 +-
 app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java      | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/app/src/main/java/com/frank/ffmpeg/activity/AudioHandleActivity.kt b/app/src/main/java/com/frank/ffmpeg/activity/AudioHandleActivity.kt
index 94d5cac..3a3e0fb 100644
--- a/app/src/main/java/com/frank/ffmpeg/activity/AudioHandleActivity.kt
+++ b/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)
             }
diff --git a/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java b/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java
index 09b05b2..1edd382 100644
--- a/app/src/main/java/com/frank/ffmpeg/util/FFmpegUtil.java
+++ b/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) {
-            throw new IllegalArgumentException("audio speed range is from 0.5 to 2");
+        // atempo range [0.5, 100.0]
+        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);