DecimationInfo.java

/*
 *  DecimationInfo.java
 *  Eisenkraut
 *
 *  Copyright (c) 2004-2016 Hanns Holger Rutz. All rights reserved.
 *
 *  This software is published under the GNU General Public License v3+
 *
 *
 *	For further information, please contact Hanns Holger Rutz at
 *	contact@sciss.de
 */

package de.sciss.eisenkraut.io;

import de.sciss.io.Span;

/**
 *  A context object for GUI elements
 *  that wish to load sense data at an
 *  economic data rate, i.e. by using
 *  an appropriate subsampled version of
 *  the sense data. This object is returned
 *  by the <code>getBestSubsample</code> method
 *  of <code>MultirateTrackEditor</code>. The
 *  calling instance should read the <code>sublength</code>
 *  field to determine the required buffer size
 *  and then pass this object to the <code>read</code> methods
 *  in <code>MultirateTrackEditor</code>.
 *
 *  TODO: this class could be internal to mte
 */
public class DecimationInfo
{
	/**
	 *  Internal index for MultirateTrackEditor
	 */
	public final int	idx;
	protected final int	shift;
	protected final int	inlineDecim;
	/**
	 *  Time span (in full-rate frames) covered by this subsample
	 */
	public final Span	span;
	/**
	 *  Length (rounded) of the time span decimated through sub-sampling
	 */
	public final long	sublength;
	public final int	model;
	public final int	channels;

	/**
	 *  Creates a new <code>DecimationInfo</code>
	 *  data structure with the given decimation.
	 *
	 *  @param  idx			internal index for <code>MultirateTrackEditor</code>
	 *  @param  span		the originally covered time span
	 *  @param  sublength   the translated span length in decimated
	 *						frames (rounded to integer)
	 */
	protected DecimationInfo( Span span, long sublength, int channels,
							  int idx, int shift, int inlineDecim, int model )
	{
		this.span			= span;
		this.sublength		= sublength;
		this.channels		= channels;
		this.idx			= idx;
		this.shift			= shift;
		this.inlineDecim	= inlineDecim;
		this.model			= model;
	}

	/**
	 *  Returns the decimation
	 *  rate factor.
	 *
	 *  @return the factor by which the full rate is decimated,
	 *			that is, <code>decimatedRate = fullRate / returnedFactor</code>
	 */
	public int getDecimationFactor()
	{
		return( (1<<shift) * inlineDecim );
	}
	
	public long getTotalLength()
	{
		return( (sublength * inlineDecim) << shift );
	}
}