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-rw-r--r--libmad/src/layer12.c543
1 files changed, 0 insertions, 543 deletions
diff --git a/libmad/src/layer12.c b/libmad/src/layer12.c
deleted file mode 100644
index 62be832..0000000
--- a/libmad/src/layer12.c
+++ /dev/null
@@ -1,543 +0,0 @@
-/*
- * libmad - MPEG audio decoder library
- * Copyright (C) 2000-2004 Underbit Technologies, Inc.
- *
- * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * $Id: layer12.c,v 1.17 2004/02/05 09:02:39 rob Exp $
- */
-
-# ifdef HAVE_CONFIG_H
-# include "config.h"
-# endif
-
-# include "global.h"
-
-# ifdef HAVE_LIMITS_H
-# include <limits.h>
-# else
-# define CHAR_BIT 8
-# endif
-
-# include "fixed.h"
-# include "bit.h"
-# include "stream.h"
-# include "frame.h"
-# include "layer12.h"
-
-# ifdef _MSC_VER
-# pragma warning(push)
-# pragma warning(disable: 4244 4018)
-# endif
-
-/*
- * scalefactor table
- * used in both Layer I and Layer II decoding
- */
-static
-mad_fixed_t const sf_table[64] = {
-# include "sf_table.dat"
-};
-
-/* --- Layer I ------------------------------------------------------------- */
-
-/* linear scaling table */
-static
-mad_fixed_t const linear_table[14] = {
- MAD_F(0x15555555), /* 2^2 / (2^2 - 1) == 1.33333333333333 */
- MAD_F(0x12492492), /* 2^3 / (2^3 - 1) == 1.14285714285714 */
- MAD_F(0x11111111), /* 2^4 / (2^4 - 1) == 1.06666666666667 */
- MAD_F(0x10842108), /* 2^5 / (2^5 - 1) == 1.03225806451613 */
- MAD_F(0x10410410), /* 2^6 / (2^6 - 1) == 1.01587301587302 */
- MAD_F(0x10204081), /* 2^7 / (2^7 - 1) == 1.00787401574803 */
- MAD_F(0x10101010), /* 2^8 / (2^8 - 1) == 1.00392156862745 */
- MAD_F(0x10080402), /* 2^9 / (2^9 - 1) == 1.00195694716243 */
- MAD_F(0x10040100), /* 2^10 / (2^10 - 1) == 1.00097751710655 */
- MAD_F(0x10020040), /* 2^11 / (2^11 - 1) == 1.00048851978505 */
- MAD_F(0x10010010), /* 2^12 / (2^12 - 1) == 1.00024420024420 */
- MAD_F(0x10008004), /* 2^13 / (2^13 - 1) == 1.00012208521548 */
- MAD_F(0x10004001), /* 2^14 / (2^14 - 1) == 1.00006103888177 */
- MAD_F(0x10002000) /* 2^15 / (2^15 - 1) == 1.00003051850948 */
-};
-
-/*
- * NAME: I_sample()
- * DESCRIPTION: decode one requantized Layer I sample from a bitstream
- */
-static
-mad_fixed_t I_sample(struct mad_bitptr *ptr, unsigned int nb)
-{
- mad_fixed_t sample;
-
- sample = mad_bit_read(ptr, nb);
-
- /* invert most significant bit, extend sign, then scale to fixed format */
-
- sample ^= 1 << (nb - 1);
- sample |= -(sample & (1 << (nb - 1)));
-
- sample <<= MAD_F_FRACBITS - (nb - 1);
-
- /* requantize the sample */
-
- /* s'' = (2^nb / (2^nb - 1)) * (s''' + 2^(-nb + 1)) */
-
- sample += MAD_F_ONE >> (nb - 1);
-
- return mad_f_mul(sample, linear_table[nb - 2]);
-
- /* s' = factor * s'' */
- /* (to be performed by caller) */
-}
-
-/*
- * NAME: layer->I()
- * DESCRIPTION: decode a single Layer I frame
- */
-int mad_layer_I(struct mad_stream *stream, struct mad_frame *frame)
-{
- struct mad_header *header = &frame->header;
- unsigned int nch, bound, ch, s, sb, nb;
- unsigned char allocation[2][32], scalefactor[2][32];
-
- nch = MAD_NCHANNELS(header);
-
- bound = 32;
- if (header->mode == MAD_MODE_JOINT_STEREO) {
- header->flags |= MAD_FLAG_I_STEREO;
- bound = 4 + header->mode_extension * 4;
- }
-
- /* check CRC word */
-
- if (header->flags & MAD_FLAG_PROTECTION) {
- header->crc_check =
- mad_bit_crc(stream->ptr, 4 * (bound * nch + (32 - bound)),
- header->crc_check);
-
- if (header->crc_check != header->crc_target &&
- !(frame->options & MAD_OPTION_IGNORECRC)) {
- stream->error = MAD_ERROR_BADCRC;
- return -1;
- }
- }
-
- /* decode bit allocations */
-
- for (sb = 0; sb < bound; ++sb) {
- for (ch = 0; ch < nch; ++ch) {
- nb = mad_bit_read(&stream->ptr, 4);
-
- if (nb == 15) {
- stream->error = MAD_ERROR_BADBITALLOC;
- return -1;
- }
-
- allocation[ch][sb] = nb ? nb + 1 : 0;
- }
- }
-
- for (sb = bound; sb < 32; ++sb) {
- nb = mad_bit_read(&stream->ptr, 4);
-
- if (nb == 15) {
- stream->error = MAD_ERROR_BADBITALLOC;
- return -1;
- }
-
- allocation[0][sb] =
- allocation[1][sb] = nb ? nb + 1 : 0;
- }
-
- /* decode scalefactors */
-
- for (sb = 0; sb < 32; ++sb) {
- for (ch = 0; ch < nch; ++ch) {
- if (allocation[ch][sb]) {
- scalefactor[ch][sb] = mad_bit_read(&stream->ptr, 6);
-
-# if defined(OPT_STRICT)
- /*
- * Scalefactor index 63 does not appear in Table B.1 of
- * ISO/IEC 11172-3. Nonetheless, other implementations accept it,
- * so we only reject it if OPT_STRICT is defined.
- */
- if (scalefactor[ch][sb] == 63) {
- stream->error = MAD_ERROR_BADSCALEFACTOR;
- return -1;
- }
-# endif
- }
- }
- }
-
- /* decode samples */
-
- for (s = 0; s < 12; ++s) {
- for (sb = 0; sb < bound; ++sb) {
- for (ch = 0; ch < nch; ++ch) {
- nb = allocation[ch][sb];
- frame->sbsample[ch][s][sb] = nb ?
- mad_f_mul(I_sample(&stream->ptr, nb),
- sf_table[scalefactor[ch][sb]]) : 0;
- }
- }
-
- for (sb = bound; sb < 32; ++sb) {
- if ((nb = allocation[0][sb])) {
- mad_fixed_t sample;
-
- sample = I_sample(&stream->ptr, nb);
-
- for (ch = 0; ch < nch; ++ch) {
- frame->sbsample[ch][s][sb] =
- mad_f_mul(sample, sf_table[scalefactor[ch][sb]]);
- }
- }
- else {
- for (ch = 0; ch < nch; ++ch)
- frame->sbsample[ch][s][sb] = 0;
- }
- }
- }
-
- return 0;
-}
-
-/* --- Layer II ------------------------------------------------------------ */
-
-/* possible quantization per subband table */
-static
-struct {
- unsigned int sblimit;
- unsigned char const offsets[30];
-} const sbquant_table[5] = {
- /* ISO/IEC 11172-3 Table B.2a */
- { 27, { 7, 7, 7, 6, 6, 6, 6, 6, 6, 6, 6, 3, 3, 3, 3, 3, /* 0 */
- 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0 } },
- /* ISO/IEC 11172-3 Table B.2b */
- { 30, { 7, 7, 7, 6, 6, 6, 6, 6, 6, 6, 6, 3, 3, 3, 3, 3, /* 1 */
- 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0 } },
- /* ISO/IEC 11172-3 Table B.2c */
- { 8, { 5, 5, 2, 2, 2, 2, 2, 2 } }, /* 2 */
- /* ISO/IEC 11172-3 Table B.2d */
- { 12, { 5, 5, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 } }, /* 3 */
- /* ISO/IEC 13818-3 Table B.1 */
- { 30, { 4, 4, 4, 4, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, /* 4 */
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 } }
-};
-
-/* bit allocation table */
-static
-struct {
- unsigned short nbal;
- unsigned short offset;
-} const bitalloc_table[8] = {
- { 2, 0 }, /* 0 */
- { 2, 3 }, /* 1 */
- { 3, 3 }, /* 2 */
- { 3, 1 }, /* 3 */
- { 4, 2 }, /* 4 */
- { 4, 3 }, /* 5 */
- { 4, 4 }, /* 6 */
- { 4, 5 } /* 7 */
-};
-
-/* offsets into quantization class table */
-static
-unsigned char const offset_table[6][15] = {
- { 0, 1, 16 }, /* 0 */
- { 0, 1, 2, 3, 4, 5, 16 }, /* 1 */
- { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 }, /* 2 */
- { 0, 1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, /* 3 */
- { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 16 }, /* 4 */
- { 0, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 } /* 5 */
-};
-
-/* quantization class table */
-static
-struct quantclass {
- unsigned short nlevels;
- unsigned char group;
- unsigned char bits;
- mad_fixed_t C;
- mad_fixed_t D;
-} const qc_table[17] = {
-# include "qc_table.dat"
-};
-
-/*
- * NAME: II_samples()
- * DESCRIPTION: decode three requantized Layer II samples from a bitstream
- */
-static
-void II_samples(struct mad_bitptr *ptr,
- struct quantclass const *quantclass,
- mad_fixed_t output[3])
-{
- unsigned int nb, s, sample[3];
-
- if ((nb = quantclass->group)) {
- unsigned int c, nlevels;
-
- /* degrouping */
- c = mad_bit_read(ptr, quantclass->bits);
- nlevels = quantclass->nlevels;
-
- for (s = 0; s < 3; ++s) {
- sample[s] = c % nlevels;
- c /= nlevels;
- }
- }
- else {
- nb = quantclass->bits;
-
- for (s = 0; s < 3; ++s)
- sample[s] = mad_bit_read(ptr, nb);
- }
-
- for (s = 0; s < 3; ++s) {
- mad_fixed_t requantized;
-
- /* invert most significant bit, extend sign, then scale to fixed format */
-
- requantized = sample[s] ^ (1 << (nb - 1));
- requantized |= -(requantized & (1 << (nb - 1)));
-
- requantized <<= MAD_F_FRACBITS - (nb - 1);
-
- /* requantize the sample */
-
- /* s'' = C * (s''' + D) */
-
- output[s] = mad_f_mul(requantized + quantclass->D, quantclass->C);
-
- /* s' = factor * s'' */
- /* (to be performed by caller) */
- }
-}
-
-/*
- * NAME: layer->II()
- * DESCRIPTION: decode a single Layer II frame
- */
-int mad_layer_II(struct mad_stream *stream, struct mad_frame *frame)
-{
- struct mad_header *header = &frame->header;
- struct mad_bitptr start;
- unsigned int index, sblimit, nbal, nch, bound, gr, ch, s, sb;
- unsigned char const *offsets;
- unsigned char allocation[2][32], scfsi[2][32], scalefactor[2][32][3];
- mad_fixed_t samples[3];
-
- nch = MAD_NCHANNELS(header);
-
- if (header->flags & MAD_FLAG_LSF_EXT)
- index = 4;
- else if (header->flags & MAD_FLAG_FREEFORMAT)
- goto freeformat;
- else {
- unsigned long bitrate_per_channel;
-
- bitrate_per_channel = header->bitrate;
- if (nch == 2) {
- bitrate_per_channel /= 2;
-
-# if defined(OPT_STRICT)
- /*
- * ISO/IEC 11172-3 allows only single channel mode for 32, 48, 56, and
- * 80 kbps bitrates in Layer II, but some encoders ignore this
- * restriction. We enforce it if OPT_STRICT is defined.
- */
- if (bitrate_per_channel <= 28000 || bitrate_per_channel == 40000) {
- stream->error = MAD_ERROR_BADMODE;
- return -1;
- }
-# endif
- }
- else { /* nch == 1 */
- if (bitrate_per_channel > 192000) {
- /*
- * ISO/IEC 11172-3 does not allow single channel mode for 224, 256,
- * 320, or 384 kbps bitrates in Layer II.
- */
- stream->error = MAD_ERROR_BADMODE;
- return -1;
- }
- }
-
- if (bitrate_per_channel <= 48000)
- index = (header->samplerate == 32000) ? 3 : 2;
- else if (bitrate_per_channel <= 80000)
- index = 0;
- else {
- freeformat:
- index = (header->samplerate == 48000) ? 0 : 1;
- }
- }
-
- sblimit = sbquant_table[index].sblimit;
- offsets = sbquant_table[index].offsets;
-
- bound = 32;
- if (header->mode == MAD_MODE_JOINT_STEREO) {
- header->flags |= MAD_FLAG_I_STEREO;
- bound = 4 + header->mode_extension * 4;
- }
-
- if (bound > sblimit)
- bound = sblimit;
-
- start = stream->ptr;
-
- /* decode bit allocations */
-
- for (sb = 0; sb < bound; ++sb) {
- nbal = bitalloc_table[offsets[sb]].nbal;
-
- for (ch = 0; ch < nch; ++ch)
- allocation[ch][sb] = mad_bit_read(&stream->ptr, nbal);
- }
-
- for (sb = bound; sb < sblimit; ++sb) {
- nbal = bitalloc_table[offsets[sb]].nbal;
-
- allocation[0][sb] =
- allocation[1][sb] = mad_bit_read(&stream->ptr, nbal);
- }
-
- /* decode scalefactor selection info */
-
- for (sb = 0; sb < sblimit; ++sb) {
- for (ch = 0; ch < nch; ++ch) {
- if (allocation[ch][sb])
- scfsi[ch][sb] = mad_bit_read(&stream->ptr, 2);
- }
- }
-
- /* check CRC word */
-
- if (header->flags & MAD_FLAG_PROTECTION) {
- header->crc_check =
- mad_bit_crc(start, mad_bit_length(&start, &stream->ptr),
- header->crc_check);
-
- if (header->crc_check != header->crc_target &&
- !(frame->options & MAD_OPTION_IGNORECRC)) {
- stream->error = MAD_ERROR_BADCRC;
- return -1;
- }
- }
-
- /* decode scalefactors */
-
- for (sb = 0; sb < sblimit; ++sb) {
- for (ch = 0; ch < nch; ++ch) {
- if (allocation[ch][sb]) {
- scalefactor[ch][sb][0] = mad_bit_read(&stream->ptr, 6);
-
- switch (scfsi[ch][sb]) {
- case 2:
- scalefactor[ch][sb][2] =
- scalefactor[ch][sb][1] =
- scalefactor[ch][sb][0];
- break;
-
- case 0:
- scalefactor[ch][sb][1] = mad_bit_read(&stream->ptr, 6);
- /* fall through */
-
- case 1:
- case 3:
- scalefactor[ch][sb][2] = mad_bit_read(&stream->ptr, 6);
- }
-
- if (scfsi[ch][sb] & 1)
- scalefactor[ch][sb][1] = scalefactor[ch][sb][scfsi[ch][sb] - 1];
-
-# if defined(OPT_STRICT)
- /*
- * Scalefactor index 63 does not appear in Table B.1 of
- * ISO/IEC 11172-3. Nonetheless, other implementations accept it,
- * so we only reject it if OPT_STRICT is defined.
- */
- if (scalefactor[ch][sb][0] == 63 ||
- scalefactor[ch][sb][1] == 63 ||
- scalefactor[ch][sb][2] == 63) {
- stream->error = MAD_ERROR_BADSCALEFACTOR;
- return -1;
- }
-# endif
- }
- }
- }
-
- /* decode samples */
-
- for (gr = 0; gr < 12; ++gr) {
- for (sb = 0; sb < bound; ++sb) {
- for (ch = 0; ch < nch; ++ch) {
- if ((index = allocation[ch][sb])) {
- index = offset_table[bitalloc_table[offsets[sb]].offset][index - 1];
-
- II_samples(&stream->ptr, &qc_table[index], samples);
-
- for (s = 0; s < 3; ++s) {
- frame->sbsample[ch][3 * gr + s][sb] =
- mad_f_mul(samples[s], sf_table[scalefactor[ch][sb][gr / 4]]);
- }
- }
- else {
- for (s = 0; s < 3; ++s)
- frame->sbsample[ch][3 * gr + s][sb] = 0;
- }
- }
- }
-
- for (sb = bound; sb < sblimit; ++sb) {
- if ((index = allocation[0][sb])) {
- index = offset_table[bitalloc_table[offsets[sb]].offset][index - 1];
-
- II_samples(&stream->ptr, &qc_table[index], samples);
-
- for (ch = 0; ch < nch; ++ch) {
- for (s = 0; s < 3; ++s) {
- frame->sbsample[ch][3 * gr + s][sb] =
- mad_f_mul(samples[s], sf_table[scalefactor[ch][sb][gr / 4]]);
- }
- }
- }
- else {
- for (ch = 0; ch < nch; ++ch) {
- for (s = 0; s < 3; ++s)
- frame->sbsample[ch][3 * gr + s][sb] = 0;
- }
- }
- }
-
- for (ch = 0; ch < nch; ++ch) {
- for (s = 0; s < 3; ++s) {
- for (sb = sblimit; sb < 32; ++sb)
- frame->sbsample[ch][3 * gr + s][sb] = 0;
- }
- }
- }
-
- return 0;
-}
-
-# ifdef _MSC_VER
-# pragma warning(pop)
-# endif
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