Diff

--- /home/kikidonk/Devel/entagged/audioformats/mp3/util/Mp3InfoReader.java	2005-09-01 14:20:09.000000000 +0200+++ Mp3InfoReader.java	2005-12-02 00:36:09.000000000 +0100@@ -55,15 +55,23 @@ 		 		byte[] b = new byte[4]; 		raf.read(b);-		+		// BEGIN CHANGE - BHL
+		if (!( (b[0]&0xFF)==0xFF  &&  (b[1]&0xE0)==0xE0 && (b[1]&0x06)!=0  && (b[2]&0xF0)!=0xF0  && (b[2]&0x0C)!=0x0C ))
+		{
 		// search for sync mark, but also for a right bitrate, samplerate and layer(that way you can 		// read corrupted but playable files)+			b = findSync(raf, b);
+		}
+		// REMOVE OLD CODE
+		/*
 		while ( !( (b[0]&0xFF)==0xFF  &&  (b[1]&0xE0)==0xE0 && (b[1]&0x06)!=0  && (b[2]&0xF0)!=0xF0  && (b[2]&0x0C)!=0x0C ) && raf.getFilePointer() < raf.length()-4) { 			//System.err.println(sync[0]+"|"+(sync[1]&0xE0)+"|"+((sync[1]&0xE0)==0xE0)); 			raf.seek( raf.getFilePointer() - 3); 			//raf.read(sync); 			raf.read(b); 		}+		*/
+		// END CHANGE
  		//raf.seek( raf.getFilePointer() - 2 ); 		//System.err.println(raf.getFilePointer());@@ -188,5 +196,64 @@  		return value; 	}+	
+	// BEGIN CHANGE - BHL
+	// Optimized findSync routine.
+	// Reads data from disk in chunks
+	// Can reduce the time to process from 120 seconds to 2/10th of a second.
+	private byte[] findSync(RandomAccessFile raf, byte b[]) throws IOException
+	{
+		final int kBuffSize = 1024;
+		byte[] buf = new byte[kBuffSize];
+		long pos = raf.getFilePointer();
+
+		long fileLen = raf.length();
+		long remain = fileLen;
+		
+		// Copy first 4 bytes from initial read. 
+		for (int x=0;x<4;x++)
+			buf[x] = b[x];
+		
+		while (remain > 4)
+		{
+			int read = (remain > kBuffSize-4) ? kBuffSize-4 : (int) remain;
+			raf.read(buf, 4, read);
+			
+			for (int x = 0; x < read - 4; x++)
+			{
+				if ((buf[x] & 0xFF) == 0xFF && (buf[x + 1] & 0xE0) == 0xE0
+						&& (buf[x + 1] & 0x06) != 0
+						&& (buf[x + 2] & 0xF0) != 0xF0
+						&& (buf[x + 2] & 0x0C) != 0x0C)
+				{
+					
+					// for debugging purposes, you can uncomment these lines...
+					// to verify that the file position is correct.
+					// raf.seek(pos + x - 4);	// we subtract 4, since the first 4 bytes were already read.
+					// raf.read(b);
+
+					// copy sync bytes into the result 
+					for (int i = 0; i < 4; i++)
+						b[i] = buf[x + i];
+					// set file position to just after the sync bytes
+					raf.seek(pos + x);
+					
+					return b;
+				}
+				
+			}
+			
+			// Copy last 4 bytes that we didn't check into beginning of buffer.
+			for (int x=0;x<4;x++)
+				buf[x] = buf[kBuffSize-5+x];
+
+			pos += read;
+			remain -= read;
+		}
+		return null;
+	}
+	// END CHANGE - BHL
+	
+	
 }