/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.tika.parser.mp3;
import static java.nio.charset.StandardCharsets.UTF_8;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.junit.After;
import org.junit.Test;
/**
* Test class for {@code MpegStream}.
*/
public class MpegStreamTest
{
/** The stream to be tested. */
private MpegStream stream;
@After
public void tearDown() throws Exception
{
if (stream != null)
{
stream.close();
}
}
/**
* Tests whether the default test header can be found in a stream.
*
* @param bos the stream
* @throws IOException if an error occurs
*/
private void checkDefaultHeader(ByteArrayOutputStream bos)
throws IOException
{
ByteArrayInputStream in = new ByteArrayInputStream(bos.toByteArray());
stream = new MpegStream(in);
AudioFrame header = stream.nextFrame();
assertNotNull("No header found", header);
assertEquals("Wrong MPEG version", AudioFrame.MPEG_V2,
header.getVersionCode());
assertEquals("Wrong layer", AudioFrame.LAYER_3, header.getLayer());
assertEquals("Wrong bit rate", 80000, header.getBitRate());
assertEquals("Wrong sample rate", 24000, header.getSampleRate());
}
/**
* Writes the given byte the given number of times into an output stream.
*
* @param out the output stream
* @param value the value to write
* @param count the number of bytes to write
* @throws IOException if an error occurs
*/
private static void writeBytes(OutputStream out, int value, int count)
throws IOException
{
for (int i = 0; i < count; i++)
{
out.write(value);
}
}
/**
* Writes a frame header in the given output stream.
*
* @param out the output stream
* @param b2 byte 2 of the header
* @param b3 byte 3 of the header
* @param b4 byte 4 of the header
* @throws IOException if an error occurs
*/
private static void writeFrame(OutputStream out, int b2, int b3, int b4)
throws IOException
{
out.write(0xFF);
out.write(b2);
out.write(b3);
out.write(b4);
}
/**
* Tests whether an audio frame header can be found somewhere in a stream.
*/
@Test
public void testSearchNextFrame() throws IOException
{
ByteArrayOutputStream bos = new ByteArrayOutputStream();
writeBytes(bos, 0xFF, 32);
writeBytes(bos, 0, 16);
writeBytes(bos, 0xFF, 8);
bos.write(0xF3);
bos.write(0x96);
bos.write(0);
checkDefaultHeader(bos);
}
/**
* Tests whether invalid frame headers are detected and skipped.
*/
@Test
public void testSearchNextFrameInvalid() throws IOException
{
ByteArrayOutputStream bos = new ByteArrayOutputStream();
writeFrame(bos, 0xEB, 0x96, 0);
writeFrame(bos, 0xF9, 0x96, 0);
writeFrame(bos, 0xF3, 0, 0);
writeFrame(bos, 0xF3, 0xF0, 0);
writeFrame(bos, 0xF3, 0x7C, 0);
writeFrame(bos, 0xF3, 0x96, 0);
checkDefaultHeader(bos);
}
/**
* Tests a search for another frame which is interrupted because the stream
* ends.
*/
@Test
public void testSeachNextFrameEOS() throws IOException
{
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bos.write(0xFF);
bos.write(0xFF);
bos.write(0xF3);
bos.write(0x96);
ByteArrayInputStream in = new ByteArrayInputStream(bos.toByteArray());
stream = new MpegStream(in);
assertNull("Got a frame", stream.nextFrame());
}
/**
* Tries to skip a frame if no current header is available.
*/
@Test
public void testSkipNoCurrentHeader() throws IOException
{
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bos.write("This is a test".getBytes(UTF_8));
ByteArrayInputStream in = new ByteArrayInputStream(bos.toByteArray());
stream = new MpegStream(in);
assertFalse("Wrong result", stream.skipFrame());
}
}