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-rwxr-xr-xcodecs/mp3/src/dec8.c339
1 files changed, 0 insertions, 339 deletions
diff --git a/codecs/mp3/src/dec8.c b/codecs/mp3/src/dec8.c
deleted file mode 100755
index 50ec0a9ad..000000000
--- a/codecs/mp3/src/dec8.c
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@@ -1,339 +0,0 @@
-/*____________________________________________________________________________
-
- FreeAmp - The Free MP3 Player
-
- MP3 Decoder originally Copyright (C) 1995-1997 Xing Technology
- Corp. http://www.xingtech.com
-
- Portions Copyright (C) 1998-1999 EMusic.com
-
- 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., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id$
-____________________________________________________________________________*/
-
-/**** dec8.c ***************************************************
-
-
-ANSI C
-MPEG audio decoder Layer II only mpeg1 and mpeg2
-output sample type and sample rate conversion
- decode mpeg to 8000Ks mono
- output 16 bit linear, 8 bit linear, or u-law
-
-
-mod 6/29/95 bugfix in u-law table
-
-mod 11/15/95 for Layer I
-
-mod 1/7/97 minor mods for warnings
-
-******************************************************************/
-/*****************************************************************
-
- MPEG audio software decoder portable ANSI c.
- Decodes all Layer II to 8000Ks mono pcm.
- Output selectable: 16 bit linear, 8 bit linear, u-law.
-
--------------------------------------
-int audio_decode8_init(MPEG_HEAD *h, int framebytes_arg,
- int reduction_code, int transform_code, int convert_code,
- int freq_limit)
-
-initilize decoder:
- return 0 = fail, not 0 = success
-
-MPEG_HEAD *h input, mpeg header info (returned by call to head_info)
-framebytes input, mpeg frame size (returned by call to head_info)
-reduction_code input, ignored
-transform_code input, ignored
-convert_code input, set convert_code = 4*bit_code + chan_code
- bit_code: 1 = 16 bit linear pcm
- 2 = 8 bit (unsigned) linear pcm
- 3 = u-law (8 bits unsigned)
- chan_code: 0 = convert two chan to mono
- 1 = convert two chan to mono
- 2 = convert two chan to left chan
- 3 = convert two chan to right chan
-freq_limit input, ignored
-
-
----------------------------------
-void audio_decode8_info( DEC_INFO *info)
-
-information return:
- Call after audio_decode8_init. See mhead.h for
- information returned in DEC_INFO structure.
-
-
----------------------------------
-IN_OUT audio_decode8(unsigned char *bs, void *pcmbuf)
-
-decode one mpeg audio frame:
-bs input, mpeg bitstream, must start with
- sync word. Caution: may read up to 3 bytes
- beyond end of frame.
-pcmbuf output, pcm samples.
-
-IN_OUT structure returns:
- Number bytes conceptually removed from mpeg bitstream.
- Returns 0 if sync loss.
- Number bytes of pcm output. This may vary from frame
- to frame.
-
-*****************************************************************/
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <float.h>
-#include <string.h>
-#include <math.h>
-#include "L3.h"
-#include "mhead.h" /* mpeg header structure */
-
-
-
-
-
-/*------------------------------------------*/
-static int output_code;
-static int convert(void *mv, unsigned char *pcm);
-static int convert_8bit(void *mv, unsigned char *pcm);
-static int convert_u(void *mv, unsigned char *pcm);
-static CVT_FUNCTION_8 cvt_table[3] =
-{
- convert,
- convert_8bit,
- convert_u,
-};
-
-void mpeg8_init(MPEG8 *m)
-{
- memset(&m->dec, 0, sizeof(m->dec));
- m->dec.ncnt = 8 * 288;
- m->dec.ncnt1 = 8 * 287;
- m->dec.nlast = 287;
- m->dec.ndeci = 11;
- m->dec.kdeci = 8 * 288;
- m->dec.first_pass = 1;
-}
-
-/*====================================================================*/
-IN_OUT audio_decode8(MPEG8 *m, unsigned char *bs, signed short *pcmbuf)
-{
- IN_OUT x;
-
- x = audio_decode(&m->cupper, bs, m->dec.pcm);
- if (x.in_bytes <= 0)
- return x;
- x.out_bytes = m->dec.convert_routine(m, (void *) pcmbuf);
-
- return x;
-}
-/*--------------8Ks 16 bit pcm --------------------------------*/
-static int convert(void *mv, unsigned char y0[])
-{
- MPEG8 *m = mv;
- int i, k;
- long alpha;
- short *y;
-
- y = (short *) y0;
- k = 0;
- if (m->dec.kdeci < m->dec.ncnt)
- {
- alpha = m->dec.kdeci & 7;
- y[k++] = (short) (m->dec.xsave + ((alpha * (m->dec.pcm[0] - m->dec.xsave)) >> 3));
- m->dec.kdeci += m->dec.ndeci;
- }
- m->dec.kdeci -= m->dec.ncnt;
- for (; m->dec.kdeci < m->dec.ncnt1; m->dec.kdeci += m->dec.ndeci)
- {
- i = m->dec.kdeci >> 3;
- alpha = m->dec.kdeci & 7;
- y[k++] = (short) (m->dec.pcm[i] + ((alpha * (m->dec.pcm[i + 1] - m->dec.pcm[i])) >> 3));
- }
- m->dec.xsave = m->dec.pcm[m->dec.nlast];
-
-/* printf("\n k out = %4d", k); */
-
- return sizeof(short) * k;
-}
-/*----------------8Ks 8 bit unsigned pcm ---------------------------*/
-static int convert_8bit(void *mv, unsigned char y[])
-{
- MPEG8 *m = mv;
- int i, k;
- long alpha;
-
- k = 0;
- if (m->dec.kdeci < m->dec.ncnt)
- {
- alpha = m->dec.kdeci & 7;
- y[k++] = (unsigned char) (((m->dec.xsave + ((alpha * (m->dec.pcm[0] - m->dec.xsave)) >> 3)) >> 8) + 128);
- m->dec.kdeci += m->dec.ndeci;
- }
- m->dec.kdeci -= m->dec.ncnt;
- for (; m->dec.kdeci < m->dec.ncnt1; m->dec.kdeci += m->dec.ndeci)
- {
- i = m->dec.kdeci >> 3;
- alpha = m->dec.kdeci & 7;
- y[k++] = (unsigned char) (((m->dec.pcm[i] + ((alpha * (m->dec.pcm[i + 1] - m->dec.pcm[i])) >> 3)) >> 8) + 128);
- }
- m->dec.xsave = m->dec.pcm[m->dec.nlast];
-
-/* printf("\n k out = %4d", k); */
-
- return k;
-}
-/*--------------8Ks u-law --------------------------------*/
-static int convert_u(void *mv, unsigned char y[])
-{
- MPEG8 *m = mv;
- int i, k;
- long alpha;
- unsigned char *look;
-
- look = m->dec.look_u + 4096;
-
- k = 0;
- if (m->dec.kdeci < m->dec.ncnt)
- {
- alpha = m->dec.kdeci & 7;
- y[k++] = look[(m->dec.xsave + ((alpha * (m->dec.pcm[0] - m->dec.xsave)) >> 3)) >> 3];
- m->dec.kdeci += m->dec.ndeci;
- }
- m->dec.kdeci -= m->dec.ncnt;
- for (; m->dec.kdeci < m->dec.ncnt1; m->dec.kdeci += m->dec.ndeci)
- {
- i = m->dec.kdeci >> 3;
- alpha = m->dec.kdeci & 7;
- y[k++] = look[(m->dec.pcm[i] + ((alpha * (m->dec.pcm[i + 1] - m->dec.pcm[i])) >> 3)) >> 3];
- }
- m->dec.xsave = m->dec.pcm[m->dec.nlast];
-
-/* printf("\n k out = %4d", k); */
-
- return k;
-}
-/*--------------------------------------------------------------------*/
-static int ucomp3(int x) /* re analog devices CCITT G.711 */
-{
- int s, p, y, t, u, u0, sign;
-
- sign = 0;
- if (x < 0)
- {
- x = -x;
- sign = 0x0080;
- }
- if (x > 8031)
- x = 8031;
- x += 33;
- t = x;
- for (s = 0; s < 15; s++)
- {
- if (t & 0x4000)
- break;
- t <<= 1;
- }
- y = x << s;
- p = (y >> 10) & 0x0f; /* position */
- s = 9 - s; /* segment */
- u0 = (((s << 4) | p) & 0x7f) | sign;
- u = u0 ^ 0xff;
-
- return u;
-}
-/*------------------------------------------------------------------*/
-static void table_init(MPEG8 *m)
-{
- int i;
-
- for (i = -4096; i < 4096; i++)
- m->dec.look_u[4096 + i] = (unsigned char) (ucomp3(2 * i));
-
-}
-/*-------------------------------------------------------------------*/
-int audio_decode8_init(MPEG8 *m, MPEG_HEAD * h, int framebytes_arg,
- int reduction_code, int transform_code, int convert_code,
- int freq_limit)
-{
- int istat;
- int outvals;
- static int sr_table[2][4] =
- {{22, 24, 16, 0}, {44, 48, 32, 0}};
-
- if (m->dec.first_pass)
- {
- table_init(m);
- m->dec.first_pass = 0;
- }
-
- if ((h->sync & 1) == 0)
- return 0; // fail mpeg 2.5
-
- output_code = convert_code >> 2;
- if (output_code < 1)
- output_code = 1; /* 1= 16bit 2 = 8bit 3 = u */
- if (output_code > 3)
- output_code = 3; /* 1= 16bit 2 = 8bit 3 = u */
-
- convert_code = convert_code & 3;
- if (convert_code <= 0)
- convert_code = 1; /* always cvt to mono */
-
- reduction_code = 1;
- if (h->id)
- reduction_code = 2;
-
-/* select convert routine */
- m->dec.convert_routine = cvt_table[output_code - 1];
-
-/* init decimation/convert routine */
-/*-- MPEG-2 layer III --*/
- if ((h->option == 1) && h->id == 0)
- outvals = 576 >> reduction_code;
- else if (h->option == 3)
- outvals = 384 >> reduction_code;
-/*-- layer I --*/
- else
- outvals = 1152 >> reduction_code;
- m->dec.ncnt = 8 * outvals;
- m->dec.ncnt1 = 8 * (outvals - 1);
- m->dec.nlast = outvals - 1;
- m->dec.ndeci = sr_table[h->id][h->sr_index] >> reduction_code;
- m->dec.kdeci = 8 * outvals;
-/* printf("\n outvals %d", outvals); */
-
- freq_limit = 3200;
- istat = audio_decode_init(&m->cupper, h, framebytes_arg,
- reduction_code, transform_code, convert_code,
- freq_limit);
-
-
- return istat;
-}
-/*-----------------------------------------------------------------*/
-void audio_decode8_info(MPEG8 *m, DEC_INFO * info)
-{
-
- audio_decode_info(&m->cupper, info);
- info->samprate = 8000;
- if (output_code != 1)
- info->bits = 8;
- if (output_code == 3)
- info->type = 10;
-}
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