soundstreamhead2.java

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/*
 * JSwiff is an open source Java API for Macromedia Flash file generation
 * and manipulation
 *
 * Copyright (C) 2004-2008 Ralf Terdic ([e-mail])
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package com.jswiff.swfrecords.tags;

import com.jswiff.io.InputBitStream;
import com.jswiff.io.OutputBitStream;

import java.io.IOException;


/**
 * <p>
 * This tag is used to define the format of streaming sound data (contained in
 * <code>SoundStreamBlock</code> tags). It extends the
 * <code>SoundStreamHead</code> tag in flexibility, supporting more encoding
 * formats and sample sizes.
 * </p>
 * 
 * <p>
 * Warning: you are responsible for obtaining technology licenses needed for
 * encoding and decoding sound data (see e.g. <a
 * href="http://mp3licensing.com">mp3licensing.com</a> for details on mp3
 * licensing).
 * </p>
 *
 * @see SoundStreamHead
 * @see SoundStreamBlock
 */
public final class SoundStreamHead2 extends Tag {
	/**
	 * Uncompressed sound format. For 16-bit samples, native byte ordering
	 * (little-endian or big-endian) is used. Warning: this introduces
	 * platform dependency!
	 */
	public static final byte FORMAT_UNCOMPRESSED			   = 0;
	/**
	 * ADPCM compressed sound format (simple compression algorithm without
	 * licensing issues).
	 */
	public static final byte FORMAT_ADPCM					   = 1;
	/**
	 * mp3 compressed sound format (for high-quality sound encoding) (since SWF
	 * 4).
	 */
	public static final byte FORMAT_MP3						   = 2;
	/**
	 * Uncompressed little-endian sound format, i.e. 16-bit samples are decoded
	 * using little-endian byte ordering (platform-independent format) (since
	 * SWF 4).
	 */
	public static final byte FORMAT_UNCOMPRESSED_LITTLE_ENDIAN = 3;
	/**
	 * Nellymoser Asao compressed sound format (optimized for low-bitrate mono
	 * speech transmission) (since SWF 6).
	 */
	public static final byte FORMAT_NELLYMOSER				   = 6;
	/** 5.5 kHz sampling rate */
	public static final byte RATE_5500_HZ					   = 0;
	/** 11 kHz sampling rate */
	public static final byte RATE_11000_HZ					   = 1;
	/** 22 kHz sampling rate */
	public static final byte RATE_22000_HZ					   = 2;
	/** 44 kHz sampling rate */
	public static final byte RATE_44000_HZ					   = 3;
	private byte playbackRate;
	private boolean isPlayback16BitSample;
	private boolean isPlaybackStereo;
	private byte streamFormat;
	private byte streamRate;
	private boolean isStream16BitSample;
	private boolean isStreamStereo;
	private int streamSampleCount;
	private short latencySeek;

	/**
	 * <p>
	 * Creates a new SoundStreamHead2 tag. Supply the encoding format of the
	 * stream (one of the provided <code>FORMAT_...</code> constants), its
	 * sampling rate (use <code>RATE_...</code> constants), specify whether
	 * the sample size is 16 bit or 8 bit, and provide the channel count (mono
	 * / stereo) and the average number of samples (for stereo sound: sample
	 * pairs) per SoundStreamBlock.
	 * </p>
	 * 
	 * <p>
	 * The advisory playback parameters (sampling rate, sample size and channel
	 * count) are set to be identical to the stream's parameters specified
	 * here. Use <code>setPlayback...()</code> methods for changing these
	 * values.
	 * </p>
	 *
	 * @param format encoding format (mp3 or ADPCM)
	 * @param rate sampling rate
	 * @param is16BitSample if <code>true</code>, sample size is 16 bit,
	 * 		  otherwise 8 bit
	 * @param isStereo if <code>true</code>, sound is stereo, otherwise mono
	 * @param sampleCount average number of samples (stereo: sample pairs) per
	 * 		  block
	 */
	public SoundStreamHead2(
		byte format, byte rate, boolean is16BitSample, boolean isStereo,
		int sampleCount) {
		code						   = TagConstants.SOUND_STREAM_HEAD_2;
		this.streamFormat			   = format;
		this.streamRate				   = rate;
		this.playbackRate			   = rate;
		this.isStream16BitSample	   = is16BitSample;
		this.isPlayback16BitSample     = is16BitSample;
		this.isStreamStereo			   = isStereo;
		this.isPlaybackStereo		   = isStereo;
		this.streamSampleCount		   = sampleCount;
	}

	SoundStreamHead2() {
		// empty
	}

	/**
	 * Used only with mp3 streaming sounds; sets the number of mp3 samples to
	 * be skipped at the beginning of the sound stream (initial latency). This
	 * value must match the number of mp3 samples to be skipped (i.e. the
	 * SeekSamples value) from the first SoundStreamBlock.
	 *
	 * @param latencySeek initial latency of sound stream
	 */
	public void setLatencySeek(short latencySeek) {
		this.latencySeek = latencySeek;
	}

	/**
	 * Used only with mp3 streaming sounds; returns the number of mp3 samples
	 * to be skipped at the beginning of the sound stream (initial latency).
	 *
	 * @return initial latency of sound stream
	 */
	public short getLatencySeek() {
		return latencySeek;
	}

	/**
	 * Sets the sample size for playback (16 bit / 8 bit).
	 *
	 * @param is16BitSample <code>true</code> for 16 bit, <code>false</code>
	 * 		  for 8 bit
	 */
	public void setPlayback16BitSample(boolean is16BitSample) {
		this.isPlayback16BitSample = is16BitSample;
	}

	/**
	 * Checks the sample size for playback (16 bit / 8 bit).
	 *
	 * @return <code>true</code> for 16 bit, <code>false</code> for 8 bit
	 */
	public boolean isPlayback16BitSample() {
		return isPlayback16BitSample;
	}

	/**
	 * Sets the playback sampling rate.
	 *
	 * @param rate advisory playback rate
	 */
	public void setPlaybackRate(byte rate) {
		this.playbackRate = rate;
	}

	/**
	 * Returns the playback sampling rate.
	 *
	 * @return advisory playback rate
	 */
	public byte getPlaybackRate() {
		return playbackRate;
	}

	/**
	 * Sets the number of channels used at playback (mono/stereo).
	 *
	 * @param isStereo <code>true</code> for stereo, <code>false</code> for
	 * 		  mono
	 */
	public void setPlaybackStereo(boolean isStereo) {
		this.isPlaybackStereo = isStereo;
	}

	/**
	 * Checks the number of channels used at playback (mono/stereo).
	 *
	 * @return <code>true</code> for stereo, <code>false for mono</code>
	 */
	public boolean isPlaybackStereo() {
		return isPlaybackStereo;
	}

	/**
	 * Specifies the sound stream's sample size (16 bit / 8 bit).
	 *
	 * @param isStream16BitSample <code>true</code> for 16 bit,
	 * 		  <code>false</code> for 8 bit
	 */
	public void setStream16BitSample(boolean isStream16BitSample) {
		this.isStream16BitSample = isStream16BitSample;
	}

	/**
	 * Checks the sound stream's sample size (16 bit / 8 bit).
	 *
	 * @return <code>true</code> for 16 bit, <code>false</code> for 8 bit
	 */
	public boolean isStream16BitSample() {
		return isStream16BitSample;
	}

	/**
	 * Specifies the encoding format of the sound stream (one of the
	 * <code>FORMAT_...</code> constants).
	 *
	 * @param streamFormat sound encoding format
	 */
	public void setStreamFormat(byte streamFormat) {
		this.streamFormat = streamFormat;
	}

	/**
	 * Returns the encoding format of the sound stream (one of the
	 * <code>FORMAT_...</code> constants).
	 *
	 * @return sound encoding format
	 */
	public byte getStreamFormat() {
		return streamFormat;
	}

	/**
	 * Specifies the sampling rate of the sound stream (one of the
	 * <code>RATE_...</code> constants).
	 *
	 * @param streamRate sampling rate
	 */
	public void setStreamRate(byte streamRate) {
		this.streamRate = streamRate;
	}

	/**
	 * Returns the sampling rate of the sound stream (one of the
	 * <code>RATE_...</code> constants).
	 *
	 * @return sampling rate
	 */
	public byte getStreamRate() {
		return streamRate;
	}

	/**
	 * Specifies the average number of samples (for stereo sound: sample pairs)
	 * per SoundStreamBlock.
	 *
	 * @param streamSampleCount average sample count per block
	 */
	public void setStreamSampleCount(int streamSampleCount) {
		this.streamSampleCount = streamSampleCount;
	}

	/**
	 * Returns the average number of samples (for stereo sound: sample pairs)
	 * per SoundStreamBlock.
	 *
	 * @return average sample count per block
	 */
	public int getStreamSampleCount() {
		return streamSampleCount;
	}

	/**
	 * Specifies whether the streaming sound is stereo or not.
	 *
	 * @param isStreamStereo <code>true</code> if stereo, otherwise
	 * 		  <code>false</code>
	 */
	public void setStreamStereo(boolean isStreamStereo) {
		this.isStreamStereo = isStreamStereo;
	}

	/**
	 * Checks whether the streaming sound is stereo or not.
	 *
	 * @return <code>true</code> if stereo, otherwise <code>false</code>
	 */
	public boolean isStreamStereo() {
		return isStreamStereo;
	}

	protected void writeData(OutputBitStream outStream)
		throws IOException {
		outStream.writeUnsignedBits(0, 4); // 4 reserved bits
		outStream.writeUnsignedBits(playbackRate, 2);
		outStream.writeBooleanBit(isPlayback16BitSample);
		outStream.writeBooleanBit(isPlaybackStereo);
		outStream.writeUnsignedBits(streamFormat, 4);
		outStream.writeUnsignedBits(streamRate, 2);
		outStream.writeBooleanBit(isStream16BitSample);
		outStream.writeBooleanBit(isStreamStereo);
		outStream.writeUI16(streamSampleCount);
		if (streamFormat == FORMAT_MP3) {
			outStream.writeSI16(latencySeek);
		}
	}

	void setData(byte[] data) throws IOException {
		InputBitStream inStream = new InputBitStream(data);
		inStream.readUnsignedBits(4); // 4 reserved bits
		playbackRate			  = (byte) inStream.readUnsignedBits(2);
		isPlayback16BitSample     = inStream.readBooleanBit();
		isPlaybackStereo		  = inStream.readBooleanBit();
		streamFormat			  = (byte) inStream.readUnsignedBits(4);
		streamRate				  = (byte) inStream.readUnsignedBits(2);
		isStream16BitSample		  = inStream.readBooleanBit();
		isStreamStereo			  = inStream.readBooleanBit();
		streamSampleCount		  = inStream.readUI16();
		if ((streamFormat == FORMAT_MP3) && (data.length > 4)) {
			latencySeek = inStream.readSI16();
		}
	}
}