net.sourceforge.javaflacencoder.MetadataBlockStreamInfo Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of java-flac-encoder Show documentation

javaFlacEncoder is a pure java implementation of a FLAC encoder library. It is designed to allow third-party java applications to enable flac encoding without resorting to use of JNI or scripted file conversions. Additionally, a basic console wav->flac encoding tool is included as part of this package. Original project can be found here: http://javaflacencoder.sourceforge.net/

The newest version!

/*
 * Copyright (C) 2010  Preston Lacey http://javaflacencoder.sourceforge.net/
 * All Rights Reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

package net.sourceforge.javaflacencoder;

/**
 * MetadataBlockStreamInfo is used to declare the initial stream parameters,
 * such as Sample Rate, bits per sample, and number of channels, as well as
 * information on the encoded stream such as total number of samples, minimum
 * and maximum block and frame sizes, and md5sum of raw audio samples. A
 * StreamInfo block must be the first meta-data block in a FLAC stream, and only
 * one StreamInfo block may exist.
 *
 * @author Preston Lacey
 */
public class MetadataBlockStreamInfo {
  /** For Debugging: Higher level equals more debug statements */
  static int DEBUG_LEV = 0;
  /*    int minimumBlockSize = 4096;//32768;//16 bits used; 16 minimum valid
    int maximumBlockSize = 4096;//32768;//16 bits used; 65535 maximum valid
    int minimumFrameSize = 0;//24 bits used; zero implies unknown
    int maximumFrameSize = 0;//24 bits used; zero implies unknown
    int sampleRate = 8000;//4096;//20 bits used, but 655350Hz max. 0 is invalid.
    byte numberOfChannels = 1;//3 bits used
    byte bitsPerSample = 16;//5 bits used. values 4-32 valid
    long totalSamplesInStream = 0;//36 bits used. 0 implies unknown.
    byte[] md5Hash;
  */
  /**
   * Constructor. This class defines only static methods and fields.
   */
  public MetadataBlockStreamInfo() {

  }

  /**
   * Create a FLAC StreamInfo metadata block with the given parameters. Because
   * of the data stored in a StreamInfo block, this should generally be created
   * only after all encoding is done.
   *
   * @param sc StreamConfiguration used in this FLAC stream.
   * @param minFrameSize Size of smallest frame in FLAC stream.
   * @param maxFrameSize Size of largest frame in FLAC stream.
   * @param samplesInStream Total number of inter-channel audio samples in
   * FLAC stream.
   * @param md5Hash MD5 hash of the raw audio samples.
   * @return EncodedElement containing created StreamInfo block.
   */
  public static EncodedElement getStreamInfo(StreamConfiguration sc,
      int minFrameSize, int maxFrameSize, long samplesInStream, byte[] md5Hash) {
    int bytes = getByteSize();
    EncodedElement ele = new EncodedElement(bytes, 0);
    int encodedBitsPerSample = sc.getBitsPerSample()-1;
    ele.addInt(sc.getMinBlockSize(), 16);
    ele.addInt(sc.getMaxBlockSize(), 16);
    ele.addInt(minFrameSize, 24);
    ele.addInt(maxFrameSize, 24);
    ele.addInt(sc.getSampleRate(), 20);
    ele.addInt(sc.getChannelCount()-1, 3);
    ele.addInt(encodedBitsPerSample, 5);
    ele.addLong(samplesInStream, 36);
    for(int i = 0; i < 16; i++) {
      ele.addInt(md5Hash[i], 8);
    }
    return ele;
  }

  /**
   * Get the expected size of a properly formed STREAMINFO metadata block.
   *
   * @return size of properly formed FLAC STREAMINFO metadata block.
   */
  static public int getByteSize() {
    int size = 0;
    size += 16;
    size += 16;
    size += 24;
    size += 24;
    size += 20;
    size += 3;
    size += 5;
    size += 36;
    size += 64;
    size += 64;
    size = size/8;
    return size;
  }
}