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audacity/lib-src/mpglib/common.c
James Crook 5e0efd1a25 Start on built-in LAME 
Using LAME 3.10
Windows project files substantially changed from original, and included into audacity solution.
2019-03-26 17:46:53 +00:00

365 lines
9.7 KiB
C
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/*
* common.c: some common bitstream operations
*
* Copyright (C) 1999-2010 The L.A.M.E. project
*
* Initially written by Michael Hipp, see also AUTHORS and README.
*
* This library 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 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/* $Id: common.c,v 1.42 2017/08/19 14:20:27 robert Exp $ */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <ctype.h>
#include <stdlib.h>
#include <signal.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef macintosh
#include <types.h>
#include <stat.h>
#else
#include <sys/types.h>
#include <sys/stat.h>
#endif
#include <assert.h>
#include "common.h"
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif
/* In C++ the array first must be prototyped, why ? */
/* *INDENT-OFF* */
const int tabsel_123 [2] [3] [16] = {
{ {0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,},
{0,32,48,56, 64, 80, 96,112,128,160,192,224,256,320,384,},
{0,32,40,48, 56, 64, 80, 96,112,128,160,192,224,256,320,} },
{ {0,32,48,56,64,80,96,112,128,144,160,176,192,224,256,},
{0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,},
{0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,} }
};
const long freqs[9] = { 44100, 48000, 32000,
22050, 24000, 16000,
11025, 12000, 8000 };
/* *INDENT-ON* */
real muls[27][64];
#if 0
static void
get_II_stuff(struct frame *fr)
{
/* *INDENT-OFF* */
static const int translate [3] [2] [16] = /* char ? */
{ { { 0,2,2,2,2,2,2,0,0,0,1,1,1,1,1,0 } ,
{ 0,2,2,0,0,0,1,1,1,1,1,1,1,1,1,0 } } ,
{ { 0,2,2,2,2,2,2,0,0,0,0,0,0,0,0,0 } ,
{ 0,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0 } } ,
{ { 0,3,3,3,3,3,3,0,0,0,1,1,1,1,1,0 } ,
{ 0,3,3,0,0,0,1,1,1,1,1,1,1,1,1,0 } } };
/* *INDENT-ON* */
int table, sblim;
static const struct al_table2 *tables[5] = { alloc_0, alloc_1, alloc_2, alloc_3, alloc_4 };
static int sblims[5] = { 27, 30, 8, 12, 30 };
if (fr->lsf)
table = 4;
else
table = translate[fr->sampling_frequency][2 - fr->stereo][fr->bitrate_index];
sblim = sblims[table];
fr->alloc = tables[table];
fr->II_sblimit = sblim;
}
#endif
#define HDRCMPMASK 0xfffffd00
#define MAX_INPUT_FRAMESIZE 4096
int
head_check(unsigned long head, int check_layer)
{
/*
look for a valid header.
if check_layer > 0, then require that
nLayer = check_layer.
*/
/* bits 13-14 = layer 3 */
int nLayer = 4 - ((head >> 17) & 3);
if ((head & 0xffe00000) != 0xffe00000) {
/* syncword */
return FALSE;
}
if (nLayer == 4)
return FALSE;
if (check_layer > 0 && nLayer != check_layer)
return FALSE;
if (((head >> 12) & 0xf) == 0xf) {
/* bits 16,17,18,19 = 1111 invalid bitrate */
return FALSE;
}
if (((head >> 10) & 0x3) == 0x3) {
/* bits 20,21 = 11 invalid sampling freq */
return FALSE;
}
if ((head & 0x3) == 0x2)
/* invalid emphasis */
return FALSE;
return TRUE;
}
#if 0
static void
print_header(PMPSTR mp, struct frame *fr)
{
static const char *modes[4] = { "Stereo", "Joint-Stereo", "Dual-Channel", "Single-Channel" };
static const char *layers[4] = { "Unknown", "I", "II", "III" };
lame_report_fnc(mp->report_msg, "MPEG %s, Layer: %s, Freq: %ld, mode: %s, modext: %d, BPF : %d\n",
fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"),
layers[fr->lay], freqs[fr->sampling_frequency],
modes[fr->mode], fr->mode_ext, fr->framesize + 4);
lame_report_fnc(mp->report_msg, "Channels: %d, copyright: %s, original: %s, CRC: %s, emphasis: %d.\n",
fr->stereo, fr->copyright ? "Yes" : "No",
fr->original ? "Yes" : "No", fr->error_protection ? "Yes" : "No", fr->emphasis);
lame_report_fnc(mp->report_msg, "Bitrate: %d Kbits/s, Extension value: %d\n",
tabsel_123[fr->lsf][fr->lay - 1][fr->bitrate_index], fr->extension);
}
static void
print_header_compact(PMPSTR mp, struct frame *fr)
{
static const char *modes[4] = { "stereo", "joint-stereo", "dual-channel", "mono" };
static const char *layers[4] = { "Unknown", "I", "II", "III" };
lame_report_fnc(mp->report_err, "MPEG %s layer %s, %d kbit/s, %ld Hz %s\n",
fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"),
layers[fr->lay],
tabsel_123[fr->lsf][fr->lay - 1][fr->bitrate_index],
freqs[fr->sampling_frequency], modes[fr->mode]);
}
#endif
/*
* decode a header and write the information
* into the frame structure
*/
int
decode_header(PMPSTR mp, struct frame *fr, unsigned long newhead)
{
if (newhead & (1 << 20)) {
fr->lsf = (newhead & (1 << 19)) ? 0x0 : 0x1;
fr->mpeg25 = 0;
}
else {
fr->lsf = 1;
fr->mpeg25 = 1;
}
fr->lay = 4 - ((newhead >> 17) & 3);
if (fr->lay != 3 && fr->mpeg25) {
lame_report_fnc(mp->report_err, "MPEG-2.5 is supported by Layer3 only\n");
return 0;
}
if (((newhead >> 10) & 0x3) == 0x3) {
lame_report_fnc(mp->report_err, "Stream error\n");
return 0;
}
if (fr->mpeg25) {
fr->sampling_frequency = 6 + ((newhead >> 10) & 0x3);
}
else
fr->sampling_frequency = ((newhead >> 10) & 0x3) + (fr->lsf * 3);
fr->error_protection = ((newhead >> 16) & 0x1) ^ 0x1;
if (fr->mpeg25) /* allow Bitrate change for 2.5 ... */
fr->bitrate_index = ((newhead >> 12) & 0xf);
fr->bitrate_index = ((newhead >> 12) & 0xf);
fr->padding = ((newhead >> 9) & 0x1);
fr->extension = ((newhead >> 8) & 0x1);
fr->mode = ((newhead >> 6) & 0x3);
fr->mode_ext = ((newhead >> 4) & 0x3);
fr->copyright = ((newhead >> 3) & 0x1);
fr->original = ((newhead >> 2) & 0x1);
fr->emphasis = newhead & 0x3;
fr->stereo = (fr->mode == MPG_MD_MONO) ? 1 : 2;
switch (fr->lay) {
case 1:
fr->framesize = (long) tabsel_123[fr->lsf][0][fr->bitrate_index] * 12000;
fr->framesize /= freqs[fr->sampling_frequency];
fr->framesize = ((fr->framesize + fr->padding) << 2) - 4;
fr->down_sample = 0;
fr->down_sample_sblimit = SBLIMIT >> (fr->down_sample);
break;
case 2:
fr->framesize = (long) tabsel_123[fr->lsf][1][fr->bitrate_index] * 144000;
fr->framesize /= freqs[fr->sampling_frequency];
fr->framesize += fr->padding - 4;
fr->down_sample = 0;
fr->down_sample_sblimit = SBLIMIT >> (fr->down_sample);
break;
case 3:
#if 0
fr->do_layer = do_layer3;
if (fr->lsf)
ssize = (fr->stereo == 1) ? 9 : 17;
else
ssize = (fr->stereo == 1) ? 17 : 32;
#endif
#if 0
if (fr->error_protection)
ssize += 2;
#endif
if (fr->framesize > MAX_INPUT_FRAMESIZE) {
lame_report_fnc(mp->report_err, "Frame size too big.\n");
fr->framesize = MAX_INPUT_FRAMESIZE;
return (0);
}
if (fr->bitrate_index == 0)
fr->framesize = 0;
else {
fr->framesize = (long) tabsel_123[fr->lsf][2][fr->bitrate_index] * 144000;
fr->framesize /= freqs[fr->sampling_frequency] << (fr->lsf);
fr->framesize = fr->framesize + fr->padding - 4;
}
break;
default:
lame_report_fnc(mp->report_err, "Sorry, layer %d not supported\n", fr->lay);
return (0);
}
/* print_header(mp, fr); */
return 1;
}
unsigned int
getbits(PMPSTR mp, int number_of_bits)
{
unsigned long rval;
if (number_of_bits <= 0 || !mp->wordpointer)
return 0;
{
rval = mp->wordpointer[0];
rval <<= 8;
rval |= mp->wordpointer[1];
rval <<= 8;
rval |= mp->wordpointer[2];
rval <<= mp->bitindex;
rval &= 0xffffff;
mp->bitindex += number_of_bits;
rval >>= (24 - number_of_bits);
mp->wordpointer += (mp->bitindex >> 3);
mp->bitindex &= 7;
}
return rval;
}
unsigned int
getbits_fast(PMPSTR mp, int number_of_bits)
{
unsigned long rval;
{
rval = mp->wordpointer[0];
rval <<= 8;
rval |= mp->wordpointer[1];
rval <<= mp->bitindex;
rval &= 0xffff;
mp->bitindex += number_of_bits;
rval >>= (16 - number_of_bits);
mp->wordpointer += (mp->bitindex >> 3);
mp->bitindex &= 7;
}
return rval;
}
unsigned char
get_leq_8_bits(PMPSTR mp, unsigned int number_of_bits)
{
assert(number_of_bits <= 8);
return (unsigned char) getbits_fast(mp, number_of_bits);
}
unsigned short
get_leq_16_bits(PMPSTR mp, unsigned int number_of_bits)
{
assert(number_of_bits <= 16);
return (unsigned short) getbits_fast(mp, number_of_bits);
}
int
set_pointer(PMPSTR mp, long backstep)
{
unsigned char *bsbufold;
if (mp->fsizeold < 0 && backstep > 0) {
lame_report_fnc(mp->report_err, "hip: Can't step back %ld bytes!\n", backstep);
return MP3_ERR;
}
bsbufold = mp->bsspace[1 - mp->bsnum] + 512;
mp->wordpointer -= backstep;
if (backstep)
memcpy(mp->wordpointer, bsbufold + mp->fsizeold - backstep, (size_t) backstep);
mp->bitindex = 0;
return MP3_OK;
}
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