9fee0ec4ca
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7101 a1c6a512-1295-4272-9138-f99709370657
88 lines
2.7 KiB
Java
88 lines
2.7 KiB
Java
/*
|
|
* 11/19/04 1.0 moved to LGPL.
|
|
* 12/12/99 Added appendSamples() method for efficiency. MDM.
|
|
* 15/02/99 ,Java Conversion by E.B ,ebsp@iname.com, JavaLayer
|
|
*
|
|
* Declarations for output buffer, includes operating system
|
|
* implementation of the virtual Obuffer. Optional routines
|
|
* enabling seeks and stops added by Jeff Tsay.
|
|
*
|
|
* @(#) obuffer.h 1.8, last edit: 6/15/94 16:51:56
|
|
* @(#) Copyright (C) 1993, 1994 Tobias Bading (bading@cs.tu-berlin.de)
|
|
* @(#) Berlin University of Technology
|
|
*
|
|
* Idea and first implementation for u-law output with fast downsampling by
|
|
* Jim Boucher (jboucher@flash.bu.edu)
|
|
*
|
|
* LinuxObuffer class written by
|
|
* Louis P. Kruger (lpkruger@phoenix.princeton.edu)
|
|
*-----------------------------------------------------------------------
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU Library 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 Library General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Library General Public
|
|
* License along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*----------------------------------------------------------------------
|
|
*/
|
|
package javazoom.jl.decoder;
|
|
|
|
/**
|
|
* Base Class for audio output.
|
|
*/
|
|
public abstract class Obuffer
|
|
{
|
|
public static final int OBUFFERSIZE = 2 * 1152; // max. 2 * 1152 samples per frame
|
|
public static final int MAXCHANNELS = 2; // max. number of channels
|
|
|
|
/**
|
|
* Takes a 16 Bit PCM sample.
|
|
*/
|
|
public abstract void append(int channel, short value);
|
|
|
|
/**
|
|
* Accepts 32 new PCM samples.
|
|
*/
|
|
public void appendSamples(int channel, float[] f)
|
|
{
|
|
short s;
|
|
for (int i=0; i<32;)
|
|
{
|
|
s = clip(f[i++]);
|
|
append(channel, s);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Clip Sample to 16 Bits
|
|
*/
|
|
private final short clip(float sample)
|
|
{
|
|
return ((sample > 32767.0f) ? 32767 :
|
|
((sample < -32768.0f) ? -32768 :
|
|
(short) sample));
|
|
}
|
|
|
|
/**
|
|
* Write the samples to the file or directly to the audio hardware.
|
|
*/
|
|
public abstract void write_buffer(int val);
|
|
public abstract void close();
|
|
|
|
/**
|
|
* Clears all data in the buffer (for seeking).
|
|
*/
|
|
public abstract void clear_buffer();
|
|
|
|
/**
|
|
* Notify the buffer that the user has stopped the stream.
|
|
*/
|
|
public abstract void set_stop_flag();
|
|
}
|