Handle streaming audio as frames (#1244)

src/main/java/io/github/dsheirer/audio/convert/MP3FrameTools.java

@@ -0,0 +1,59 @@
+/*
+ * *****************************************************************************
+ * Copyright (C) 2014-2022 Dennis Sheirer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ * ****************************************************************************
+ */
+package io.github.dsheirer.audio.convert;
+
+import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.commons.math3.util.FastMath;
+
+public class MP3FrameTools {
+
+    private MP3FrameTools() {}
+
+    /**
+     * Split MP3 audio at frame boundaries
+     * @param input byte array of audio
+     * @return list of byte arrays containing audio frames
+     */
+    public static MP3AudioFrames split(byte[] input)
+    {
+        List<byte[]> mp3Frames = new ArrayList<>();
+        int audioDuration = 0;
+
+        int offset = 0;
+        while(offset < input.length)
+        {
+            if(MP3Header.hasSync(input, offset))
+            {
+                int framelen = MP3Header.getFrameLength(input, offset);
+                mp3Frames.add(Arrays.copyOfRange(input, offset, offset + FastMath.min(framelen, input.length - offset)));
+                audioDuration += MP3Header.getFrameDuration(input, offset);
+                offset += framelen;
+            }
+            else
+            {
+                offset += 1;
+            }
+        }
+
+        return new MP3AudioFrames(audioDuration, mp3Frames);
+    }
+
+}