/*
* MP3 bitstream Output interface for LAME
*
* Copyright (c) 1999-2000 Mark Taylor
* Copyright (c) 1999-2002 Takehiro Tominaga
*
* 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: bitstream.c,v 1.69.2.1 2005/11/20 14:08:24 bouvigne Exp $
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdlib.h>
#include <assert.h>
#include <stdio.h>
#include "tables.h"
#include "bitstream.h"
#include "quantize.h"
#include "quantize_pvt.h"
#include "version.h"
#include "VbrTag.h"
#include "machine.h"
#include "gain_analysis.h"
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif
/* unsigned int is at least this large: */
/* we work with ints, so when doing bit manipulation, we limit
* ourselves to MAX_LENGTH-2 just to be on the safe side */
#define MAX_LENGTH 32
#ifdef DEBUG
static int hoge, hogege;
#endif
/***********************************************************************
* compute bitsperframe and mean_bits for a layer III frame
**********************************************************************/
int getframebits(const lame_global_flags * gfp)
{
lame_internal_flags *gfc=gfp->internal_flags;
int bit_rate;
/* get bitrate in kbps [?] */
if (gfc->bitrate_index)
bit_rate = bitrate_table[gfp->version][gfc->bitrate_index];
else
bit_rate = gfp->brate;
assert ( bit_rate <= 550 );
/* main encoding routine toggles padding on and off */
/* one Layer3 Slot consists of 8 bits */
return 8 * ((gfp->version+1)*72000*bit_rate / gfp->out_samplerate
+ gfc->padding);
}
void putheader_bits(lame_internal_flags *gfc)
{
Bit_stream_struc *bs;
bs = &gfc->bs;
#ifdef DEBUG
hoge += gfc->sideinfo_len * 8;
hogege += gfc->sideinfo_len * 8;
#endif
memcpy(&bs->buf[bs->buf_byte_idx], gfc->header[gfc->w_ptr].buf,
gfc->sideinfo_len);
bs->buf_byte_idx += gfc->sideinfo_len;
bs->totbit += gfc->sideinfo_len * 8;
gfc->w_ptr = (gfc->w_ptr + 1) & (MAX_HEADER_BUF - 1);
}
/*write j bits into the bit stream */
inline static void
putbits2(lame_internal_flags *gfc, int val, int j)
{
Bit_stream_struc *bs;
bs = &gfc->bs;
assert(j < MAX_LENGTH-2);
while (j > 0) {
int k;
if (bs->buf_bit_idx == 0) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx++;
assert(bs->buf_byte_idx < BUFFER_SIZE);
assert(gfc->header[gfc->w_ptr].write_timing >= bs->totbit);
if (gfc->header[gfc->w_ptr].write_timing == bs->totbit) {
putheader_bits(gfc);
}
bs->buf[bs->buf_byte_idx] = 0;
}
k = Min(j, bs->buf_bit_idx);
j -= k;
bs->buf_bit_idx -= k;
assert (j < MAX_LENGTH); /* 32 too large on 32 bit machines */
assert (bs->buf_bit_idx < MAX_LENGTH);
bs->buf[bs->buf_byte_idx] |= ((val >> j) << bs->buf_bit_idx);
bs->totbit += k;
}
}
/*write j bits into the bit stream, ignoring frame headers */
inline static void
putbits_noheaders(lame_internal_flags *gfc, int val, int j)
{
Bit_stream_struc *bs;
bs = &gfc->bs;
assert(j < MAX_LENGTH-2);
while (j > 0) {
int k;
if (bs->buf_bit_idx == 0) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx++;
assert(bs->buf_byte_idx < BUFFER_SIZE);
bs->buf[bs->buf_byte_idx] = 0;
}
k = Min(j, bs->buf_bit_idx);
j -= k;
bs->buf_bit_idx -= k;
assert (j < MAX_LENGTH); /* 32 too large on 32 bit machines */
assert (bs->buf_bit_idx < MAX_LENGTH);
bs->buf[bs->buf_byte_idx] |= ((val >> j) << bs->buf_bit_idx);
bs->totbit += k;
}
}
/*
Some combinations of bitrate, Fs, and stereo make it impossible to stuff
out a frame using just main_data, due to the limited number of bits to
indicate main_data_length. In these situations, we put stuffing bits into
the ancillary data...
*/
inline static void
drain_into_ancillary(lame_global_flags *gfp, int remainingBits)
{
lame_internal_flags *gfc=gfp->internal_flags;
int i;
assert(remainingBits >= 0);
if (remainingBits >= 8) {
putbits2(gfc,0x4c,8);
remainingBits -= 8;
}
if (remainingBits >= 8) {
putbits2(gfc,0x41,8);
remainingBits -= 8;
}
if (remainingBits >= 8) {
putbits2(gfc,0x4d,8);
remainingBits -= 8;
}
if (remainingBits >= 8) {
putbits2(gfc,0x45,8);
remainingBits -= 8;
}
if (remainingBits >= 32) {
const char *version = get_lame_short_version ();
if (remainingBits >= 32)
for (i=0; i<(int)strlen(version) && remainingBits >=8 ; ++i) {
remainingBits -= 8;
putbits2(gfc,version[i],8);
}
}
for (; remainingBits >= 1; remainingBits -= 1 ) {
putbits2(gfc, gfc->ancillary_flag, 1 );
gfc->ancillary_flag ^= !gfp->disable_reservoir;
}
assert (remainingBits == 0);
}
/*write N bits into the header */
inline static void
writeheader(lame_internal_flags *gfc,int val, int j)
{
int ptr = gfc->header[gfc->h_ptr].ptr;
while (j > 0) {
int k = Min(j, 8 - (ptr & 7));
j -= k;
assert (j < MAX_LENGTH); /* >> 32 too large for 32 bit machines */
gfc->header[gfc->h_ptr].buf[ptr >> 3]
|= ((val >> j)) << (8 - (ptr & 7) - k);
ptr += k;
}
gfc->header[gfc->h_ptr].ptr = ptr;
}
static int
CRC_update(int value, int crc)
{
int i;
value <<= 8;
for (i = 0; i < 8; i++) {
value <<= 1;
crc <<= 1;
if (((crc ^ value) & 0x10000))
crc ^= CRC16_POLYNOMIAL;
}
return crc;
}
void
CRC_writeheader(lame_internal_flags *gfc, char *header)
{
int crc = 0xffff; /* (jo) init crc16 for error_protection */
int i;
crc = CRC_update(((unsigned char*)header)[2], crc);
crc = CRC_update(((unsigned char*)header)[3], crc);
for (i = 6; i < gfc->sideinfo_len; i++) {
crc = CRC_update(((unsigned char*)header)[i], crc);
}
header[4] = crc >> 8;
header[5] = crc & 255;
}
inline static void
encodeSideInfo2(lame_global_flags *gfp,int bitsPerFrame)
{
lame_internal_flags *gfc=gfp->internal_flags;
III_side_info_t *l3_side;
int gr, ch;
l3_side = &gfc->l3_side;
gfc->header[gfc->h_ptr].ptr = 0;
memset(gfc->header[gfc->h_ptr].buf, 0, gfc->sideinfo_len);
if (gfp->out_samplerate < 16000)
writeheader(gfc,0xffe, 12);
else
writeheader(gfc,0xfff, 12);
writeheader(gfc,(gfp->version), 1);
writeheader(gfc,4 - 3, 2);
writeheader(gfc,(!gfp->error_protection), 1);
writeheader(gfc,(gfc->bitrate_index), 4);
writeheader(gfc,(gfc->samplerate_index), 2);
writeheader(gfc,(gfc->padding), 1);
writeheader(gfc,(gfp->extension), 1);
writeheader(gfc,(gfp->mode), 2);
writeheader(gfc,(gfc->mode_ext), 2);
writeheader(gfc,(gfp->copyright), 1);
writeheader(gfc,(gfp->original), 1);
writeheader(gfc,(gfp->emphasis), 2);
if (gfp->error_protection) {
writeheader(gfc,0, 16); /* dummy */
}
if (gfp->version == 1) {
/* MPEG1 */
assert(l3_side->main_data_begin >= 0);
writeheader(gfc,(l3_side->main_data_begin), 9);
if (gfc->channels_out == 2)
writeheader(gfc,l3_side->private_bits, 3);
else
writeheader(gfc,l3_side->private_bits, 5);
for (ch = 0; ch < gfc->channels_out; ch++) {
int band;
for (band = 0; band < 4; band++) {
writeheader(gfc,l3_side->scfsi[ch][band], 1);
}
}
for (gr = 0; gr < 2; gr++) {
for (ch = 0; ch < gfc->channels_out; ch++) {
gr_info *gi = &l3_side->tt[gr][ch];
writeheader(gfc,gi->part2_3_length+gi->part2_length, 12);
writeheader(gfc,gi->big_values / 2, 9);
writeheader(gfc,gi->global_gain, 8);
writeheader(gfc,gi->scalefac_compress, 4);
if (gi->block_type != NORM_TYPE) {
writeheader(gfc, 1, 1); /* window_switching_flag */
writeheader(gfc,gi->block_type, 2);
writeheader(gfc,gi->mixed_block_flag, 1);
if (gi->table_select[0] == 14)
gi->table_select[0] = 16;
writeheader(gfc,gi->table_select[0], 5);
if (gi->table_select[1] == 14)
gi->table_select[1] = 16;
writeheader(gfc,gi->table_select[1], 5);
writeheader(gfc,gi->subblock_gain[0], 3);
writeheader(gfc,gi->subblock_gain[1], 3);
writeheader(gfc,gi->subblock_gain[2], 3);
} else {
writeheader(gfc, 0, 1); /* window_switching_flag */
if (gi->table_select[0] == 14)
gi->table_select[0] = 16;
writeheader(gfc,gi->table_select[0], 5);
if (gi->table_select[1] == 14)
gi->table_select[1] = 16;
writeheader(gfc,gi->table_select[1], 5);
if (gi->table_select[2] == 14)
gi->table_select[2] = 16;
writeheader(gfc,gi->table_select[2], 5);
assert(gi->region0_count < 16U);
assert(gi->region1_count < 8U);
writeheader(gfc,gi->region0_count, 4);
writeheader(gfc,gi->region1_count, 3);
}
writeheader(gfc,gi->preflag, 1);
writeheader(gfc,gi->scalefac_scale, 1);
writeheader(gfc,gi->count1table_select, 1);
}
}
} else {
/* MPEG2 */
assert(l3_side->main_data_begin >= 0);
writeheader(gfc,(l3_side->main_data_begin), 8);
writeheader(gfc,l3_side->private_bits, gfc->channels_out);
gr = 0;
for (ch = 0; ch < gfc->channels_out; ch++) {
gr_info *gi = &l3_side->tt[gr][ch];
writeheader(gfc,gi->part2_3_length+gi->part2_length, 12);
writeheader(gfc,gi->big_values / 2, 9);
writeheader(gfc,gi->global_gain, 8);
writeheader(gfc,gi->scalefac_compress, 9);
if (gi->block_type != NORM_TYPE) {
writeheader(gfc, 1, 1); /* window_switching_flag */
writeheader(gfc,gi->block_type, 2);
writeheader(gfc,gi->mixed_block_flag, 1);
if (gi->table_select[0] == 14)
gi->table_select[0] = 16;
writeheader(gfc,gi->table_select[0], 5);
if (gi->table_select[1] == 14)
gi->table_select[1] = 16;
writeheader(gfc,gi->table_select[1], 5);
writeheader(gfc,gi->subblock_gain[0], 3);
writeheader(gfc,gi->subblock_gain[1], 3);
writeheader(gfc,gi->subblock_gain[2], 3);
} else {
writeheader(gfc, 0, 1); /* window_switching_flag */
if (gi->table_select[0] == 14)
gi->table_select[0] = 16;
writeheader(gfc,gi->table_select[0], 5);
if (gi->table_select[1] == 14)
gi->table_select[1] = 16;
writeheader(gfc,gi->table_select[1], 5);
if (gi->table_select[2] == 14)
gi->table_select[2] = 16;
writeheader(gfc,gi->table_select[2], 5);
assert(gi->region0_count < 16U);
assert(gi->region1_count < 8U);
writeheader(gfc,gi->region0_count, 4);
writeheader(gfc,gi->region1_count, 3);
}
writeheader(gfc,gi->scalefac_scale, 1);
writeheader(gfc,gi->count1table_select, 1);
}
}
if (gfp->error_protection) {
/* (jo) error_protection: add crc16 information to header */
CRC_writeheader(gfc, gfc->header[gfc->h_ptr].buf);
}
{
int old = gfc->h_ptr;
assert(gfc->header[old].ptr == gfc->sideinfo_len * 8);
gfc->h_ptr = (old + 1) & (MAX_HEADER_BUF - 1);
gfc->header[gfc->h_ptr].write_timing =
gfc->header[old].write_timing + bitsPerFrame;
if (gfc->h_ptr == gfc->w_ptr) {
/* yikes! we are out of header buffer space */
ERRORF(gfc,"Error: MAX_HEADER_BUF too small in bitstream.c \n");
}
}
}
inline static int
huffman_coder_count1(lame_internal_flags *gfc, gr_info *gi)
{
/* Write count1 area */
const struct huffcodetab *h = &ht[gi->count1table_select + 32];
int i,bits=0;
#ifdef DEBUG
int gegebo = gfc->bs.totbit;
#endif
int *ix = &gi->l3_enc[gi->big_values];
FLOAT *xr = &gi->xr[gi->big_values];
assert(gi->count1table_select < 2);
for (i = (gi->count1 - gi->big_values) / 4; i > 0; --i) {
int huffbits = 0;
int p = 0, v;
v = ix[0];
if (v) {
p += 8;
if (xr[0] < 0)
huffbits++;
assert(v <= 1u);
}
v = ix[1];
if (v) {
p += 4;
huffbits *= 2;
if (xr[1] < 0)
huffbits++;
assert(v <= 1u);
}
v = ix[2];
if (v) {
p += 2;
huffbits *= 2;
if (xr[2] < 0)
huffbits++;
assert(v <= 1u);
}
v = ix[3];
if (v) {
p++;
huffbits *= 2;
if (xr[3] < 0)
huffbits++;
assert(v <= 1u);
}
ix += 4;
xr += 4;
putbits2(gfc, huffbits + h->table[p], h->hlen[p]);
bits += h->hlen[p];
}
#ifdef DEBUG
DEBUGF(gfc,"count1: real: %ld counted:%d (bigv %d count1len %d)\n",
gfc->bs.totbit -gegebo, gi->count1bits, gi->big_values, gi->count1);
#endif
return bits;
}
/*
Implements the pseudocode of page 98 of the IS
*/
inline static int
Huffmancode( lame_internal_flags* const gfc, const int tableindex,
int start, int end, gr_info *gi)
{
const struct huffcodetab* h = &ht[tableindex];
int index, bits = 0;
assert(tableindex < 32u);
if (!tableindex)
return bits;
for (index = start; index < end; index += 2) {
int cbits = 0;
int xbits = 0;
int linbits = h->xlen;
int xlen = h->xlen;
int ext = 0;
int x1 = gi->l3_enc[index];
int x2 = gi->l3_enc[index+1];
if (x1 != 0) {
if (gi->xr[index] < 0)
ext++;
cbits--;
}
if (tableindex > 15) {
/* use ESC-words */
if (x1 > 14) {
int linbits_x1 = x1 - 15;
assert ( linbits_x1 <= h->linmax );
ext |= linbits_x1 << 1;
xbits = linbits;
x1 = 15;
}
if (x2 > 14) {
int linbits_x2 = x2 - 15;
assert ( linbits_x2 <= h->linmax );
ext <<= linbits;
ext |= linbits_x2;
xbits += linbits;
x2 = 15;
}
xlen = 16;
}
if (x2 != 0) {
ext <<= 1;
if (gi->xr[index+1] < 0)
ext++;
cbits--;
}
assert ( (x1|x2) < 16u );
x1 = x1 * xlen + x2;
xbits -= cbits;
cbits += h->hlen [x1];
assert ( cbits <= MAX_LENGTH );
assert ( xbits <= MAX_LENGTH );
putbits2(gfc, h->table [x1], cbits );
putbits2(gfc, ext, xbits );
bits += cbits + xbits;
}
return bits;
}
/*
Note the discussion of huffmancodebits() on pages 28
and 29 of the IS, as well as the definitions of the side
information on pages 26 and 27.
*/
static int
ShortHuffmancodebits(lame_internal_flags *gfc, gr_info *gi)
{
int bits;
int region1Start;
region1Start = 3*gfc->scalefac_band.s[3];
if (region1Start > gi->big_values)
region1Start = gi->big_values;
/* short blocks do not have a region2 */
bits = Huffmancode(gfc, gi->table_select[0], 0, region1Start, gi);
bits += Huffmancode(gfc, gi->table_select[1], region1Start, gi->big_values, gi);
return bits;
}
static int
LongHuffmancodebits(lame_internal_flags *gfc, gr_info *gi)
{
int i, bigvalues, bits;
int region1Start, region2Start;
bigvalues = gi->big_values;
assert(0 <= bigvalues && bigvalues <= 576);
i = gi->region0_count + 1;
assert(i < 23);
region1Start = gfc->scalefac_band.l[i];
i += gi->region1_count + 1;
assert(i < 23);
region2Start = gfc->scalefac_band.l[i];
if (region1Start > bigvalues)
region1Start = bigvalues;
if (region2Start > bigvalues)
region2Start = bigvalues;
bits =Huffmancode(gfc, gi->table_select[0], 0, region1Start, gi);
bits +=Huffmancode(gfc, gi->table_select[1], region1Start, region2Start, gi);
bits +=Huffmancode(gfc, gi->table_select[2], region2Start, bigvalues, gi);
return bits;
}
inline static int
writeMainData ( lame_global_flags * const gfp)
{
int gr, ch, sfb,data_bits,tot_bits=0;
lame_internal_flags *gfc=gfp->internal_flags;
III_side_info_t *l3_side;
l3_side = &gfc->l3_side;
if (gfp->version == 1) {
/* MPEG 1 */
for (gr = 0; gr < 2; gr++) {
for (ch = 0; ch < gfc->channels_out; ch++) {
gr_info *gi = &l3_side->tt[gr][ch];
int slen1 = slen1_tab[gi->scalefac_compress];
int slen2 = slen2_tab[gi->scalefac_compress];
data_bits=0;
#ifdef DEBUG
hogege = gfc->bs.totbit;
#endif
for (sfb = 0; sfb < gi->sfbdivide; sfb++) {
if (gi->scalefac[sfb] == -1)
continue; /* scfsi is used */
putbits2(gfc, gi->scalefac[sfb], slen1);
data_bits += slen1;
}
for (; sfb < gi->sfbmax; sfb++) {
if (gi->scalefac[sfb] == -1)
continue; /* scfsi is used */
putbits2(gfc, gi->scalefac[sfb], slen2);
data_bits += slen2;
}
assert(data_bits == gi->part2_length);
if (gi->block_type == SHORT_TYPE) {
data_bits += ShortHuffmancodebits(gfc, gi);
} else {
data_bits += LongHuffmancodebits(gfc, gi);
}
data_bits += huffman_coder_count1(gfc, gi);
#ifdef DEBUG
DEBUGF(gfc,"<%ld> ", gfc->bs.totbit-hogege);
#endif
/* does bitcount in quantize.c agree with actual bit count?*/
assert(data_bits == gi->part2_3_length + gi->part2_length);
tot_bits += data_bits;
} /* for ch */
} /* for gr */
} else {
/* MPEG 2 */
gr = 0;
for (ch = 0; ch < gfc->channels_out; ch++) {
gr_info *gi = &l3_side->tt[gr][ch];
int i, sfb_partition, scale_bits=0;
assert(gi->sfb_partition_table);
data_bits = 0;
#ifdef DEBUG
hogege = gfc->bs.totbit;
#endif
sfb = 0;
sfb_partition = 0;
if (gi->block_type == SHORT_TYPE) {
for (; sfb_partition < 4; sfb_partition++) {
int sfbs = gi->sfb_partition_table[sfb_partition] / 3;
int slen = gi->slen[sfb_partition];
for (i = 0; i < sfbs; i++, sfb++) {
putbits2(gfc, Max(gi->scalefac[sfb*3+0], 0U), slen);
putbits2(gfc, Max(gi->scalefac[sfb*3+1], 0U), slen);
putbits2(gfc, Max(gi->scalefac[sfb*3+2], 0U), slen);
scale_bits += 3*slen;
}
}
data_bits += ShortHuffmancodebits(gfc, gi);
} else {
for (; sfb_partition < 4; sfb_partition++) {
int sfbs = gi->sfb_partition_table[sfb_partition];
int slen = gi->slen[sfb_partition];
for (i = 0; i < sfbs; i++, sfb++) {
putbits2(gfc, Max(gi->scalefac[sfb], 0U), slen);
scale_bits += slen;
}
}
data_bits +=LongHuffmancodebits(gfc, gi);
}
data_bits +=huffman_coder_count1(gfc, gi);
#ifdef DEBUG
DEBUGF(gfc,"<%ld> ", gfc->bs.totbit-hogege);
#endif
/* does bitcount in quantize.c agree with actual bit count?*/
assert(data_bits==gi->part2_3_length);
assert(scale_bits==gi->part2_length);
tot_bits += scale_bits + data_bits;
} /* for ch */
} /* for gf */
return tot_bits;
} /* main_data */
/* compute the number of bits required to flush all mp3 frames
currently in the buffer. This should be the same as the
reservoir size. Only call this routine between frames - i.e.
only after all headers and data have been added to the buffer
by format_bitstream().
Also compute total_bits_output =
size of mp3 buffer (including frame headers which may not
have yet been send to the mp3 buffer) +
number of bits needed to flush all mp3 frames.
total_bytes_output is the size of the mp3 output buffer if
lame_encode_flush_nogap() was called right now.
*/
int
compute_flushbits( const lame_global_flags * gfp, int *total_bytes_output )
{
lame_internal_flags *gfc=gfp->internal_flags;
int flushbits,remaining_headers;
int bitsPerFrame;
int last_ptr,first_ptr;
first_ptr=gfc->w_ptr; /* first header to add to bitstream */
last_ptr = gfc->h_ptr - 1; /* last header to add to bitstream */
if (last_ptr==-1) last_ptr=MAX_HEADER_BUF-1;
/* add this many bits to bitstream so we can flush all headers */
flushbits = gfc->header[last_ptr].write_timing - gfc->bs.totbit;
*total_bytes_output=flushbits;
if (flushbits >= 0) {
/* if flushbits >= 0, some headers have not yet been written */
/* reduce flushbits by the size of the headers */
remaining_headers= 1+last_ptr - first_ptr;
if (last_ptr < first_ptr)
remaining_headers= 1+last_ptr - first_ptr + MAX_HEADER_BUF;
flushbits -= remaining_headers*8*gfc->sideinfo_len;
}
/* finally, add some bits so that the last frame is complete
* these bits are not necessary to decode the last frame, but
* some decoders will ignore last frame if these bits are missing
*/
bitsPerFrame = getframebits(gfp);
flushbits += bitsPerFrame;
*total_bytes_output += bitsPerFrame;
/* round up: */
if (*total_bytes_output % 8)
*total_bytes_output = 1 + (*total_bytes_output/8);
else
*total_bytes_output = (*total_bytes_output/8);
*total_bytes_output += gfc->bs.buf_byte_idx + 1;
if (flushbits<0) {
#if 0
/* if flushbits < 0, this would mean that the buffer looks like:
* (data...) last_header (data...) (extra data that should not be here...)
*/
DEBUGF(gfc,"last header write_timing = %i \n",gfc->header[last_ptr].write_timing);
DEBUGF(gfc,"first header write_timing = %i \n",gfc->header[first_ptr].write_timing);
DEBUGF(gfc,"bs.totbit: %i \n",gfc->bs.totbit);
DEBUGF(gfc,"first_ptr, last_ptr %i %i \n",first_ptr,last_ptr);
DEBUGF(gfc,"remaining_headers = %i \n",remaining_headers);
DEBUGF(gfc,"bitsperframe: %i \n",bitsPerFrame);
DEBUGF(gfc,"sidelen: %i \n",gfc->sideinfo_len);
#endif
ERRORF(gfc,"strange error flushing buffer ... \n");
}
return flushbits;
}
void
flush_bitstream(lame_global_flags *gfp)
{
lame_internal_flags *gfc=gfp->internal_flags;
III_side_info_t *l3_side;
int nbytes;
int flushbits;
int last_ptr,first_ptr;
first_ptr=gfc->w_ptr; /* first header to add to bitstream */
last_ptr = gfc->h_ptr - 1; /* last header to add to bitstream */
if (last_ptr==-1) last_ptr=MAX_HEADER_BUF-1;
l3_side = &gfc->l3_side;
if ((flushbits = compute_flushbits(gfp,&nbytes)) < 0) return;
drain_into_ancillary(gfp, flushbits);
/* check that the 100% of the last frame has been written to bitstream */
assert (gfc->header[last_ptr].write_timing + getframebits(gfp)
== gfc->bs.totbit);
/* we have padded out all frames with ancillary data, which is the
same as filling the bitreservoir with ancillary data, so : */
gfc->ResvSize=0;
l3_side->main_data_begin = 0;
/* save the ReplayGain value */
if (gfc->findReplayGain) {
FLOAT RadioGain = (FLOAT) GetTitleGain(gfc->rgdata);
assert(RadioGain != GAIN_NOT_ENOUGH_SAMPLES);
gfc->RadioGain = (int) floor( RadioGain * 10.0 + 0.5 ); /* round to nearest */
}
/* find the gain and scale change required for no clipping */
if (gfc->findPeakSample) {
gfc->noclipGainChange = (int) ceil(log10(gfc->PeakSample / 32767.0) *20.0*10.0); /* round up */
if (gfc->noclipGainChange > 0) { /* clipping occurs */
if (gfp->scale == 1.0 || gfp->scale == 0.0)
gfc->noclipScale = floor( (32767.0 / gfc->PeakSample) * 100.0 ) / 100.0; /* round down */
else
/* the user specified his own scaling factor. We could suggest
* the scaling factor of (32767.0/gfp->PeakSample)*(gfp->scale)
* but it's usually very inaccurate. So we'd rather not advice him
* on the scaling factor. */
gfc->noclipScale = -1;
}
else /* no clipping */
gfc->noclipScale = -1;
}
}
void add_dummy_byte ( lame_global_flags* const gfp, unsigned char val )
{
lame_internal_flags *gfc = gfp->internal_flags;
int i;
putbits_noheaders(gfc, val, 8);
for (i=0 ; i< MAX_HEADER_BUF ; ++i)
gfc->header[i].write_timing += 8;
}
/*
format_bitstream()
This is called after a frame of audio has been quantized and coded.
It will write the encoded audio to the bitstream. Note that
from a layer3 encoder's perspective the bit stream is primarily
a series of main_data() blocks, with header and side information
inserted at the proper locations to maintain framing. (See Figure A.7
in the IS).
*/
int
format_bitstream(lame_global_flags *gfp)
{
lame_internal_flags *gfc=gfp->internal_flags;
int bits,nbytes;
III_side_info_t *l3_side;
int bitsPerFrame;
l3_side = &gfc->l3_side;
bitsPerFrame = getframebits(gfp);
drain_into_ancillary(gfp, l3_side->resvDrain_pre);
encodeSideInfo2(gfp,bitsPerFrame);
bits = 8*gfc->sideinfo_len;
bits+=writeMainData(gfp);
drain_into_ancillary(gfp, l3_side->resvDrain_post);
bits += l3_side->resvDrain_post;
l3_side->main_data_begin += (bitsPerFrame-bits)/8;
/* compare number of bits needed to clear all buffered mp3 frames
* with what we think the resvsize is: */
if (compute_flushbits(gfp,&nbytes) != gfc->ResvSize) {
ERRORF(gfc,"Internal buffer inconsistency. flushbits <> ResvSize");
}
/* compare main_data_begin for the next frame with what we
* think the resvsize is: */
if ((l3_side->main_data_begin * 8) != gfc->ResvSize ) {
ERRORF(gfc,"bit reservoir error: \n"
"l3_side->main_data_begin: %i \n"
"Resvoir size: %i \n"
"resv drain (post) %i \n"
"resv drain (pre) %i \n"
"header and sideinfo: %i \n"
"data bits: %i \n"
"total bits: %i (remainder: %i) \n"
"bitsperframe: %i \n",
8*l3_side->main_data_begin,
gfc->ResvSize,
l3_side->resvDrain_post,
l3_side->resvDrain_pre,
8*gfc->sideinfo_len,
bits-l3_side->resvDrain_post-8*gfc->sideinfo_len,
bits, bits % 8,
bitsPerFrame
);
ERRORF(gfc,"This is a fatal error. It has several possible causes:");
ERRORF(gfc,"90% LAME compiled with buggy version of gcc using advanced optimizations");
ERRORF(gfc," 9% Your system is overclocked");
ERRORF(gfc," 1% bug in LAME encoding library");
gfc->ResvSize = l3_side->main_data_begin*8;
};
assert(gfc->bs.totbit % 8 == 0);
if (gfc->bs.totbit > 1000000000 ) {
/* to avoid totbit overflow, (at 8h encoding at 128kbs) lets reset bit counter*/
int i;
for (i=0 ; i< MAX_HEADER_BUF ; ++i)
gfc->header[i].write_timing -= gfc->bs.totbit;
gfc->bs.totbit=0;
}
return 0;
}
/* copy data out of the internal MP3 bit buffer into a user supplied
unsigned char buffer.
mp3data=0 indicates data in buffer is an id3tags and VBR tags
mp3data=1 data is real mp3 frame data.
*/
int copy_buffer(lame_internal_flags *gfc,unsigned char *buffer,int size,int mp3data)
{
Bit_stream_struc *bs=&gfc->bs;
int minimum = bs->buf_byte_idx + 1;
if (minimum <= 0) return 0;
if (size!=0 && minimum>size) return -1; /* buffer is too small */
memcpy(buffer,bs->buf,minimum);
bs->buf_byte_idx = -1;
bs->buf_bit_idx = 0;
if (mp3data) {
UpdateMusicCRC(&gfc->nMusicCRC,buffer,minimum);
#ifdef DECODE_ON_THE_FLY
if (gfc->decode_on_the_fly) { /* decode the frame */
sample_t pcm_buf[2][1152];
int mp3_in = minimum;
int samples_out = -1;
int i;
/* re-synthesis to pcm. Repeat until we get a samples_out=0 */
while(samples_out != 0) {
samples_out=lame_decode1_unclipped(buffer,mp3_in,pcm_buf[0],pcm_buf[1]);
/* samples_out = 0: need more data to decode
* samples_out = -1: error. Lets assume 0 pcm output
* samples_out = number of samples output */
/* set the lenght of the mp3 input buffer to zero, so that in the
* next iteration of the loop we will be querying mpglib about
* buffered data */
mp3_in = 0;
if (samples_out==-1) {
/* error decoding. Not fatal, but might screw up
* the ReplayGain tag. What should we do? Ignore for now */
samples_out=0;
}
if (samples_out>0) {
/* process the PCM data */
/* this should not be possible, and indicates we have
* overflown the pcm_buf buffer */
assert(samples_out <= 1152);
if (gfc->findPeakSample) {
for (i=0; i<samples_out; i++) {
if (pcm_buf[0][i] > gfc->PeakSample)
gfc->PeakSample = pcm_buf[0][i];
else if (-pcm_buf[0][i] > gfc->PeakSample)
gfc->PeakSample = -pcm_buf[0][i];
}
if (gfc->channels_out > 1)
for (i=0; i<samples_out; i++) {
if (pcm_buf[1][i] > gfc->PeakSample)
gfc->PeakSample = pcm_buf[1][i];
else if (-pcm_buf[1][i] > gfc->PeakSample)
gfc->PeakSample = -pcm_buf[1][i];
}
}
if (gfc->findReplayGain)
if (AnalyzeSamples(gfc->rgdata, pcm_buf[0], pcm_buf[1], samples_out, gfc->channels_out) == GAIN_ANALYSIS_ERROR)
return -6;
} /* if (samples_out>0) */
} /* while (samples_out!=0) */
} /* if (gfc->decode_on_the_fly) */
#endif
} /* if (mp3data) */
return minimum;
}
void init_bit_stream_w(lame_internal_flags *gfc)
{
gfc->bs.buf = (unsigned char *) malloc(BUFFER_SIZE);
gfc->bs.buf_size = BUFFER_SIZE;
gfc->h_ptr = gfc->w_ptr = 0;
gfc->header[gfc->h_ptr].write_timing = 0;
gfc->bs.buf_byte_idx = -1;
gfc->bs.buf_bit_idx = 0;
gfc->bs.totbit = 0;
}
/* end of bitstream.c */
root