Fix a bug with MPEG parsing that would lead to range exceptions (lavalink-devs#31)

markozajc · web-flow · commit 862f76c2775a · 2023-08-16T21:02:39.000+02:00
turns out dividing by smaller values yields larger quotients
i have failed basic math
diff --git a/main/src/main/java/com/sedmelluq/discord/lavaplayer/natives/mp3/Mp3Decoder.java b/main/src/main/java/com/sedmelluq/discord/lavaplayer/natives/mp3/Mp3Decoder.java
@@ -179,7 +179,7 @@ public static MpegVersion getVersion(byte[] buffer, int offset) {
 
         private static int getMaxFrameSize() {
             int bitRate = MPEG_1.bitrateIndex[MPEG_1.bitrateIndex.length - 1] * 1000;
-            int sampleRate = MPEG_1.samplerateIndex[1];
+            int sampleRate = MPEG_1.samplerateIndex[2];
             return MPEG_1.calculateFrameSize(bitRate, sampleRate, true);
         }
 

Original file line number	Diff line number	Diff line change
`@@ -179,7 +179,7 @@ public static MpegVersion getVersion(byte[] buffer, int offset) {`
`179`	`179`
`180`	`180`	`private static int getMaxFrameSize() {`
`181`	`181`	`int bitRate = MPEG_1.bitrateIndex[MPEG_1.bitrateIndex.length - 1] * 1000;`
`182`		`- int sampleRate = MPEG_1.samplerateIndex[1];`
	`182`	`+ int sampleRate = MPEG_1.samplerateIndex[2];`
`183`	`183`	`return MPEG_1.calculateFrameSize(bitRate, sampleRate, true);`
`184`	`184`	`}`
`185`	`185`