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-rw-r--r--libtoolame-dab/encode_new.c1188
1 files changed, 1188 insertions, 0 deletions
diff --git a/libtoolame-dab/encode_new.c b/libtoolame-dab/encode_new.c
new file mode 100644
index 0000000..2e797c9
--- /dev/null
+++ b/libtoolame-dab/encode_new.c
@@ -0,0 +1,1188 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include "common.h"
+#include "options.h"
+#include "bitstream.h"
+#include "availbits.h"
+#include "encode_new.h"
+
+#define NUMTABLES 5
+int vbrstats_new[15] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+
+/* There are really only 9 distinct lines in the allocation tables
+ each member of this table is an index into */
+/* step_index[linenumber][index] */
+static int step_index[9][16] = {
+ /*0*/ {0, 1, 3, 5, 6, 7, 8, 9,10,11,12,13,14,15,16,17},
+ /*1*/ {0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,17},
+ /*2*/ {0, 1, 2, 3, 4, 5, 6,17, 0, 0, 0, 0, 0, 0, 0, 0},
+ /*3*/ {0, 1, 2, 17,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+ /*4*/ {0, 1, 2, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,16},
+ /*5*/ {0, 1, 2, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0},
+ /* From ISO13818 Table B.1 */
+ /*6*/ {0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15},
+ /*7*/ {0, 1, 2, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0},
+ /*8*/ {0, 1, 2, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+};
+
+static int nbal[9] = {4, 4, 3, 2, 4, 3, 4, 3, 2};
+
+
+/* 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 */
+/* The number of steps allowed */
+static int steps[18] = {0, 3, 5, 7, 9, 15, 31, 63, 127, 255, 511, 1023, 2047, 4095, 8191, 16383, 32767, 65535};
+/* The power of 2 just under the steps value */
+static int steps2n[18]={0, 2, 4, 4, 8, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768};
+/* The bits per codeword from TableB.4 */
+static int bits[18] = {0, 5, 7, 3, 10, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+/* Samples per codeword Table B.4 Page 53 */
+//static int group[18] = {0, 3, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1};
+static int group[18] = {0, 1, 1, 3, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3};
+
+/* nbal */
+
+/* The sblimits of the 5 allocation tables
+ 4 tables for MPEG-1
+ 1 table for MPEG-2 LSF */
+static int table_sblimit[5] = {27, 30, 8, 12, 30};
+
+/* Each table contains a list of allowable quantization steps.
+ There are only 9 distinct lists of steps.
+ This table gives the index of which of the 9 lists is being used
+ A "-1" entry means that it is above the sblimit for this table */
+static int line[5][SBLIMIT] = {
+ /*00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 */
+ {0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3,-1,-1,-1,-1,-1},
+ {0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3,-1,-1},
+ {4, 4, 5, 5, 5, 5, 5, 5,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1},
+ {4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1},
+ /* LSF Table */
+ {6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}
+};
+
+/* This is ISO11172 Table B.1 */
+double scalefactor[64] = { /* Equation for nth element = 2 / (cuberoot(2) ^ n) */
+ 2.00000000000000, 1.58740105196820, 1.25992104989487,
+ 1.00000000000000, 0.79370052598410, 0.62996052494744, 0.50000000000000,
+ 0.39685026299205, 0.31498026247372, 0.25000000000000, 0.19842513149602,
+ 0.15749013123686, 0.12500000000000, 0.09921256574801, 0.07874506561843,
+ 0.06250000000000, 0.04960628287401, 0.03937253280921, 0.03125000000000,
+ 0.02480314143700, 0.01968626640461, 0.01562500000000, 0.01240157071850,
+ 0.00984313320230, 0.00781250000000, 0.00620078535925, 0.00492156660115,
+ 0.00390625000000, 0.00310039267963, 0.00246078330058, 0.00195312500000,
+ 0.00155019633981, 0.00123039165029, 0.00097656250000, 0.00077509816991,
+ 0.00061519582514, 0.00048828125000, 0.00038754908495, 0.00030759791257,
+ 0.00024414062500, 0.00019377454248, 0.00015379895629, 0.00012207031250,
+ 0.00009688727124, 0.00007689947814, 0.00006103515625, 0.00004844363562,
+ 0.00003844973907, 0.00003051757813, 0.00002422181781, 0.00001922486954,
+ 0.00001525878906, 0.00001211090890, 0.00000961243477, 0.00000762939453,
+ 0.00000605545445, 0.00000480621738, 0.00000381469727, 0.00000302772723,
+ 0.00000240310869, 0.00000190734863, 0.00000151386361, 0.00000120155435,
+ 1E-20
+};
+
+/* ISO11172 Table C.5 Layer II Signal to Noise Raios
+ MFC FIX find a reference for these in terms of bits->SNR value
+ Index into table is the steps index
+ index steps SNR
+ 0 0 0.00
+ 1 3 7.00
+ 2 5 11.00
+ 3 7 16.00
+ 4 9 20.84
+ etc
+*/
+static double SNR[18] = { 0.00, 7.00, 11.00, 16.00, 20.84,
+ 25.28, 31.59, 37.75, 43.84,
+ 49.89, 55.93, 61.96, 67.98, 74.01,
+ 80.03, 86.05, 92.01, 98.01
+};
+
+int tablenum=0;
+
+int encode_init(frame_info *frame) {
+ int ws, bsp, br_per_ch, sfrq;
+
+ bsp = frame->header->bitrate_index;
+ br_per_ch = bitrate[frame->header->version][bsp] / frame->nch;
+ ws = frame->header->sampling_frequency;
+ sfrq = s_freq[frame->header->version][ws];
+ /* decision rules refer to per-channel bitrates (kbits/sec/chan) */
+ if (frame->header->version == MPEG_AUDIO_ID) { /* MPEG-1 */
+ if ((sfrq == 48 && br_per_ch >= 56)
+ || (br_per_ch >= 56 && br_per_ch <= 80))
+ tablenum = 0;
+ else if (sfrq != 48 && br_per_ch >= 96)
+ tablenum = 1;
+ else if (sfrq != 32 && br_per_ch <= 48)
+ tablenum = 2;
+ else
+ tablenum = 3;
+ } else { /* MPEG-2 LSF */
+ tablenum = 4;
+ }
+ fprintf(stdout,"encode_init: using tablenum %i with sblimit %i\n",tablenum, table_sblimit[tablenum]);
+
+#define DUMPTABLESx
+#ifdef DUMPTABLES
+ {
+ int tablenumber,j,sblimit, sb;
+ fprintf(stdout,"Tables B.21,b,c,d from ISO11172 and the LSF table from ISO13818\n");
+ for (tablenumber=0;tablenumber<NUMTABLES;tablenumber++) {
+ /* Print Table Header */
+ fprintf(stdout,"Tablenum %i\n",tablenumber);
+ fprintf(stdout,"sb nbal ");
+ for (j=0;j<16;j++)
+ fprintf(stdout,"%6i ",j);
+ fprintf(stdout,"\n");
+ fprintf(stdout,"-----------------------------------------------------------------------------------------------------------------------\n");
+
+ sblimit = table_sblimit[tablenumber];
+ for (sb=0;sb<SBLIMIT;sb++) {
+ int thisline = line[tablenumber][sb];
+ fprintf(stdout,"%2i %4i ",sb,nbal[thisline]);
+ if (nbal[thisline] != 0)
+ for (j=0; j<(1<<nbal[thisline]); j++)
+ fprintf(stdout,"%6i ", steps[ step_index[thisline][j] ]);
+ fprintf(stdout,"\n");
+ }
+ fprintf(stdout,"\n");
+ }
+ exit(0);
+ }
+#endif
+ return (table_sblimit[tablenum]);
+}
+
+/*
+ scale_factor_calc
+ pick_scale
+ if JOINTSTEREO
+ combine_LR
+ scale_factor_calc
+ use psy model to determine SMR
+ transmission pattern
+ main_bit_allocation
+ if (error protection)
+ calc CRC
+ encode_info
+ if (error_protection)
+ encode_CRC
+ encode_bit_alloc
+ encode_scale
+ subband_quantization
+ sample_encoding
+*/
+
+
+void scalefactor_calc_new (double sb_sample[][3][SCALE_BLOCK][SBLIMIT],
+ unsigned int sf_index[][3][SBLIMIT], int nch,
+ int sblimit)
+{
+ /* Optimized to use binary search instead of linear scan through the
+ scalefactor table; guarantees to find scalefactor in only 5
+ jumps/comparisons and not in {0 (lin. best) to 63 (lin. worst)}.
+ Scalefactors for subbands > sblimit are no longer computed.
+ Uses a single sblimit-loop.
+ Patrick De Smet Oct 1999. */
+ int ch, gr;
+ /* Using '--' loops to avoid possible "cmp value + bne/beq" compiler */
+ /* inefficiencies. Below loops should compile to "bne/beq" only code */
+ for (ch = nch; ch--;)
+ for (gr = 3; gr--;) {
+ int sb;
+ for (sb = sblimit; sb--;) {
+ int j;
+ unsigned int l;
+ register double temp;
+ unsigned int scale_fac;
+ /* Determination of max. over each set of 12 subband samples: */
+ /* PDS TODO: maybe this could/should ??!! be integrated into */
+ /* the subband filtering routines? */
+ register double cur_max = fabs (sb_sample[ch][gr][SCALE_BLOCK - 1][sb]);
+ for (j = SCALE_BLOCK - 1; j--;) {
+ if ((temp = fabs (sb_sample[ch][gr][j][sb])) > cur_max)
+ cur_max = temp;
+ }
+ /* PDS: binary search in the scalefactor table: */
+ /* This is the real speed up: */
+ for (l = 16, scale_fac = 32; l; l >>= 1) {
+ if (cur_max <= scalefactor[scale_fac])
+ scale_fac += l;
+ else
+ scale_fac -= l;
+ }
+ if (cur_max > scalefactor[scale_fac])
+ scale_fac--;
+ sf_index[ch][gr][sb] = scale_fac;
+ /* There is a direct way of working out the index, if the
+ maximum value is known but since
+ it involves a log it isn't really speedy.
+ Items in the scalefactor[] table are calculated by:
+ the n'th entry = 2 / (cuberoot(2) ^ n)
+ And so using a bit of maths you get:
+ index = (int)(log(2.0/cur_max) / LNCUBEROOTTWO);
+ fprintf(stdout,"cur_max %.14lf scalefactorindex %i multiple %.14lf\n",cur_max, scale_fac, scalefactor[scale_fac]);
+ */
+ }
+ }
+}
+double mod (double a)
+{
+ return (a > 0) ? a : -a;
+}
+
+/* Combine L&R channels into a mono joint stereo channel */
+void combine_LR_new (double sb_sample[2][3][SCALE_BLOCK][SBLIMIT],
+ double joint_sample[3][SCALE_BLOCK][SBLIMIT], int sblimit) {
+ int sb, sample, gr;
+
+ for (sb = 0; sb < sblimit; ++sb)
+ for (sample = 0; sample < SCALE_BLOCK; ++sample)
+ for (gr = 0; gr < 3; ++gr)
+ joint_sample[gr][sample][sb] =
+ .5 * (sb_sample[0][gr][sample][sb] + sb_sample[1][gr][sample][sb]);
+}
+
+/* PURPOSE:For each subband, puts the smallest scalefactor of the 3
+ associated with a frame into #max_sc#. This is used
+ used by Psychoacoustic Model I.
+ Someone in dist10 source code's history, somebody wrote the following:
+ "(I would recommend changin max_sc to min_sc)"
+
+ In psy model 1, the *maximum* out of the scale picked here and
+ the maximum SPL within each subband is selected. So I'd think that
+ a maximum here makes heaps of sense.
+
+ MFC FIX: Feb 2003 - is this only needed for psy model 1?
+*/
+void find_sf_max (unsigned int sf_index[2][3][SBLIMIT], frame_info * frame,
+ double sf_max[2][SBLIMIT])
+{
+ int sb, gr, ch;
+ int lowest_sf_index;
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+
+ for (ch = 0; ch < nch; ch++)
+ for (sb = 0; sb < sblimit; sb++) {
+ for (gr = 1, lowest_sf_index = sf_index[ch][0][sb]; gr < 3; gr++)
+ if (lowest_sf_index > sf_index[ch][gr][sb])
+ lowest_sf_index = sf_index[ch][gr][sb];
+ sf_max[ch][sb] = multiple[lowest_sf_index];
+ }
+ for (sb = sblimit; sb < SBLIMIT; sb++)
+ sf_max[0][sb] = sf_max[1][sb] = 1E-20;
+}
+
+/* sf_transmission_pattern
+ PURPOSE:For a given subband, determines whether to send 1, 2, or
+ all 3 of the scalefactors, and fills in the scalefactor
+ select information accordingly
+
+ This is From ISO11172 Sect C.1.5.2.5 "coding of scalefactors"
+ and
+ Table C.4 "LayerII Scalefactors Transmission Pattern"
+*/
+void sf_transmission_pattern (unsigned int sf_index[2][3][SBLIMIT],
+ unsigned int sf_selectinfo[2][SBLIMIT],
+ frame_info * frame)
+{
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int dscf[2];
+ int class[2], i, j, k;
+ static int pattern[5][5] = { {0x123, 0x122, 0x122, 0x133, 0x123},
+ {0x113, 0x111, 0x111, 0x444, 0x113},
+ {0x111, 0x111, 0x111, 0x333, 0x113},
+ {0x222, 0x222, 0x222, 0x333, 0x123},
+ {0x123, 0x122, 0x122, 0x133, 0x123}
+ };
+
+ for (k = 0; k < nch; k++)
+ for (i = 0; i < sblimit; i++) {
+ dscf[0] = (sf_index[k][0][i] - sf_index[k][1][i]);
+ dscf[1] = (sf_index[k][1][i] - sf_index[k][2][i]);
+ for (j = 0; j < 2; j++) {
+ if (dscf[j] <= -3)
+ class[j] = 0;
+ else if (dscf[j] > -3 && dscf[j] < 0)
+ class[j] = 1;
+ else if (dscf[j] == 0)
+ class[j] = 2;
+ else if (dscf[j] > 0 && dscf[j] < 3)
+ class[j] = 3;
+ else
+ class[j] = 4;
+ }
+ switch (pattern[class[0]][class[1]]) {
+ case 0x123:
+ sf_selectinfo[k][i] = 0;
+ break;
+ case 0x122:
+ sf_selectinfo[k][i] = 3;
+ sf_index[k][2][i] = sf_index[k][1][i];
+ break;
+ case 0x133:
+ sf_selectinfo[k][i] = 3;
+ sf_index[k][1][i] = sf_index[k][2][i];
+ break;
+ case 0x113:
+ sf_selectinfo[k][i] = 1;
+ sf_index[k][1][i] = sf_index[k][0][i];
+ break;
+ case 0x111:
+ sf_selectinfo[k][i] = 2;
+ sf_index[k][1][i] = sf_index[k][2][i] = sf_index[k][0][i];
+ break;
+ case 0x222:
+ sf_selectinfo[k][i] = 2;
+ sf_index[k][0][i] = sf_index[k][2][i] = sf_index[k][1][i];
+ break;
+ case 0x333:
+ sf_selectinfo[k][i] = 2;
+ sf_index[k][0][i] = sf_index[k][1][i] = sf_index[k][2][i];
+ break;
+ case 0x444:
+ sf_selectinfo[k][i] = 2;
+ if (sf_index[k][0][i] > sf_index[k][2][i])
+ sf_index[k][0][i] = sf_index[k][2][i];
+ sf_index[k][1][i] = sf_index[k][2][i] = sf_index[k][0][i];
+ }
+ }
+}
+
+void write_header (frame_info * frame, Bit_stream_struc * bs)
+{
+ frame_header *header = frame->header;
+
+ putbits (bs, 0xfff, 12); /* syncword 12 bits */
+ put1bit (bs, header->version); /* ID 1 bit */
+ putbits (bs, 4 - header->lay, 2); /* layer 2 bits */
+ put1bit (bs, !header->error_protection); /* bit set => no err prot */
+ putbits (bs, header->bitrate_index, 4);
+ putbits (bs, header->sampling_frequency, 2);
+ put1bit (bs, header->padding);
+ put1bit (bs, header->extension); /* private_bit */
+ putbits (bs, header->mode, 2);
+ putbits (bs, header->mode_ext, 2);
+ put1bit (bs, header->copyright);
+ put1bit (bs, header->original);
+ putbits (bs, header->emphasis, 2);
+}
+
+/*************************************************************************
+ encode_bit_alloc (Layer II)
+
+ PURPOSE:Writes bit allocation information onto bitstream
+
+ 4,3,2, or 0 bits depending on the quantization table used.
+
+************************************************************************/
+void write_bit_alloc (unsigned int bit_alloc[2][SBLIMIT],
+ frame_info * frame, Bit_stream_struc * bs)
+{
+ int sb, ch;
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int jsbound = frame->jsbound;
+
+ for (sb = 0; sb < sblimit; sb++) {
+ if (sb < jsbound) {
+ for (ch = 0; ch < ((sb < jsbound) ? nch : 1); ch++)
+ putbits (bs, bit_alloc[ch][sb], nbal[ line[tablenum][sb] ]); // (*alloc)[sb][0].bits);
+ }
+ else
+ putbits (bs, bit_alloc[0][sb], nbal[ line[tablenum][sb] ]); //(*alloc)[sb][0].bits);
+ }
+}
+
+/************************************************************************
+ write_scalefactors
+
+ PURPOSE:The encoded scalar factor information is arranged and
+ queued into the output fifo to be transmitted.
+
+ The three scale factors associated with
+ a given subband and channel are transmitted in accordance
+ with the scfsi, which is transmitted first.
+
+************************************************************************/
+
+void write_scalefactors (unsigned int bit_alloc[2][SBLIMIT],
+ unsigned int sf_selectinfo[2][SBLIMIT],
+ unsigned int sf_index[2][3][SBLIMIT], frame_info * frame,
+ Bit_stream_struc * bs)
+{
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int sb, gr, ch;
+
+ /* Write out the scalefactor selection information */
+ for (sb = 0; sb < sblimit; sb++)
+ for (ch = 0; ch < nch; ch++)
+ if (bit_alloc[ch][sb])
+ putbits (bs, sf_selectinfo[ch][sb], 2);
+
+ for (sb = 0; sb < sblimit; sb++)
+ for (ch = 0; ch < nch; ch++)
+ if (bit_alloc[ch][sb]) /* above jsbound, bit_alloc[0][i] == ba[1][i] */
+ switch (sf_selectinfo[ch][sb]) {
+ case 0:
+ for (gr = 0; gr < 3; gr++)
+ putbits (bs, sf_index[ch][gr][sb], 6);
+ break;
+ case 1:
+ case 3:
+ putbits (bs, sf_index[ch][0][sb], 6);
+ putbits (bs, sf_index[ch][2][sb], 6);
+ break;
+ case 2:
+ putbits (bs, sf_index[ch][0][sb], 6);
+ }
+}
+
+
+/* ISO11172 Table C.6 Layer II quantization co-efficients */
+static double a[18] = {
+ 0,
+ 0.750000000, 0.625000000, 0.875000000, 0.562500000, 0.937500000,
+ 0.968750000, 0.984375000, 0.992187500, 0.996093750, 0.998046875,
+ 0.999023438, 0.999511719, 0.999755859, 0.999877930, 0.999938965,
+ 0.999969482, 0.999984741
+};
+
+static double b[18] = {
+ 0,
+ -0.250000000, -0.375000000, -0.125000000, -0.437500000, -0.062500000,
+ -0.031250000, -0.015625000, -0.007812500, -0.003906250, -0.001953125,
+ -0.000976563, -0.000488281, -0.000244141, -0.000122070, -0.000061035,
+ -0.000030518, -0.000015259
+};
+
+/************************************************************************
+ subband_quantization (Layer II)
+
+ PURPOSE:Quantizes subband samples to appropriate number of bits
+
+ SEMANTICS: Subband samples are divided by their scalefactors, which
+ makes the quantization more efficient. The scaled samples are
+ quantized by the function a*x+b, where a and b are functions of
+ the number of quantization levels. The result is then truncated
+ to the appropriate number of bits and the MSB is inverted.
+
+ Note that for fractional 2's complement, inverting the MSB for a
+ negative number x is equivalent to adding 1 to it.
+
+************************************************************************/
+void
+subband_quantization_new (unsigned int sf_index[2][3][SBLIMIT],
+ double sb_samples[2][3][SCALE_BLOCK][SBLIMIT],
+ unsigned int j_scale[3][SBLIMIT],
+ double j_samps[3][SCALE_BLOCK][SBLIMIT],
+ unsigned int bit_alloc[2][SBLIMIT],
+ unsigned int sbband[2][3][SCALE_BLOCK][SBLIMIT],
+ frame_info * frame)
+{
+ int sb, j, ch, gr, qnt_coeff_index, sig;
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int jsbound = frame->jsbound;
+ double d;
+
+ for (gr = 0; gr < 3; gr++)
+ for (j = 0; j < SCALE_BLOCK; j++)
+ for (sb = 0; sb < sblimit; sb++)
+ for (ch = 0; ch < ((sb < jsbound) ? nch : 1); ch++)
+
+ if (bit_alloc[ch][sb]) {
+ /* scale and quantize FLOATing point sample */
+ if (nch == 2 && sb >= jsbound) /* use j-stereo samples */
+ d = j_samps[gr][j][sb] / scalefactor[j_scale[gr][sb]];
+ else
+ d = sb_samples[ch][gr][j][sb] / scalefactor[sf_index[ch][gr][sb]];
+
+ /* Check that the wrong scale factor hasn't been chosen -
+ which would result in a scaled sample being > 1.0
+ This error shouldn't ever happen *unless* something went wrong in
+ scalefactor calc
+
+ if (mod (d) > 1.0)
+ fprintf (stderr, "Not scaled properly %d %d %d %d\n", ch, gr, j,
+ sb);
+ */
+
+ {
+ /* 'index' indicates which "step line" we are using */
+ int index = line[tablenum][sb];
+
+ /* Find the "step index" within that line */
+ qnt_coeff_index = step_index[index][bit_alloc[ch][sb]];
+ }
+ d = d * a[qnt_coeff_index] + b[qnt_coeff_index];
+
+ /* extract MSB N-1 bits from the FLOATing point sample */
+ if (d >= 0)
+ sig = 1;
+ else {
+ sig = 0;
+ d += 1.0;
+ }
+
+ sbband[ch][gr][j][sb] = (unsigned int) (d * (double)steps2n[qnt_coeff_index]);
+ /* tag the inverted sign bit to sbband at position N */
+ /* The bit inversion is a must for grouping with 3,5,9 steps
+ so it is done for all subbands */
+ if (sig)
+ sbband[ch][gr][j][sb] |= steps2n[qnt_coeff_index];
+ }
+
+ /* Set everything above the sblimit to 0 */
+ for (ch = 0; ch < nch; ch++)
+ for (gr = 0; gr < 3; gr++)
+ for (sb = 0; sb < SCALE_BLOCK; sb++)
+ for (j = sblimit; j < SBLIMIT; j++)
+ sbband[ch][gr][sb][j] = 0;
+}
+
+/************************************************************************
+ sample_encoding
+
+ PURPOSE:Put one frame of subband samples on to the bitstream
+
+ SEMANTICS: The number of bits allocated per sample is read from
+ the bit allocation information #bit_alloc#. Layer 2
+ supports writing grouped samples for quantization steps
+ that are not a power of 2.
+
+***********************************************************************/
+void write_samples_new (unsigned int sbband[2][3][SCALE_BLOCK][SBLIMIT],
+ unsigned int bit_alloc[2][SBLIMIT],
+ frame_info * frame, Bit_stream_struc * bs)
+{
+ unsigned int temp;
+ unsigned int sb, j, ch, gr, x, y;
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int jsbound = frame->jsbound;
+
+ for (gr = 0; gr < 3; gr++)
+ for (j = 0; j < SCALE_BLOCK; j += 3)
+ for (sb = 0; sb < sblimit; sb++)
+ for (ch = 0; ch < ((sb < jsbound) ? nch : 1); ch++)
+
+ if (bit_alloc[ch][sb]) {
+ int thisline = line[tablenum][sb];
+ int thisstep_index = step_index[thisline][bit_alloc[ch][sb]];
+ /* Check how many samples per codeword */
+ if (group[thisstep_index] == 3) {
+ /* Going to send 1 sample per codeword -> 3 samples */
+ for (x = 0; x < 3; x++) {
+ putbits (bs, sbband[ch][gr][j + x][sb], bits[thisstep_index]);
+ }
+ } else {
+ /* ISO11172 Sec C.1.5.2.8
+ If steps=3, 5 or 9, then three consecutive samples are coded
+ as one codeword i.e. only one value (V) is transmitted for this
+ triplet. If the 3 subband samples are x,y,z then
+ V = (steps*steps)*z + steps*y +x
+ */
+ y = steps[thisstep_index];
+ temp =
+ sbband[ch][gr][j][sb] + sbband[ch][gr][j + 1][sb] * y +
+ sbband[ch][gr][j + 2][sb] * y * y;
+ putbits (bs, temp, bits[thisstep_index]);
+ }
+ }
+}
+
+
+//#include "bit_alloc_new.c"
+/***************************************************************************************/
+/* Bit Allocation Routines */
+
+
+/************************************************************************
+*
+* bits_for_nonoise (Layer II)
+*
+* PURPOSE:Returns the number of bits required to produce a
+* mask-to-noise ratio better or equal to the noise/no_noise threshold.
+*
+* SEMANTICS:
+* bbal = # bits needed for encoding bit allocation
+* bsel = # bits needed for encoding scalefactor select information
+* banc = # bits needed for ancillary data (header info included)
+*
+* For each subband and channel, will add bits until one of the
+* following occurs:
+* - Hit maximum number of bits we can allocate for that subband
+* - MNR is better than or equal to the minimum masking level
+* (NOISY_MIN_MNR)
+* Then the bits required for scalefactors, scfsi, bit allocation,
+* and the subband samples are tallied (#req_bits#) and returned.
+*
+* (NOISY_MIN_MNR) is the smallest MNR a subband can have before it is
+* counted as 'noisy' by the logic which chooses the number of JS
+* subbands.
+*
+* Joint stereo is supported.
+*
+************************************************************************/
+
+int bits_for_nonoise_new (double SMR[2][SBLIMIT],
+ unsigned int scfsi[2][SBLIMIT], frame_info * frame, float min_mnr,
+ unsigned int bit_alloc[2][SBLIMIT])
+{
+ int sb, ch, ba;
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int jsbound = frame->jsbound;
+ int req_bits = 0, bbal = 0, berr = 0, banc = 32;
+ int maxAlloc, sel_bits, sc_bits, smp_bits;
+ static int sfsPerScfsi[] = { 3, 2, 1, 2 }; /* lookup # sfs per scfsi */
+
+ /* MFC Feb 2003
+ This works out the basic number of bits just to get a valid (but empty)
+ frame.
+ This needs to be done for every frame, since a joint_stereo frame
+ will change the number of basic bits (depending on the sblimit in
+ the particular js mode that's been selected */
+
+ /* Make sure there's room for the error protection bits */
+ if (frame->header->error_protection)
+ berr = 16;
+ else
+ berr = 0;
+
+ /* Count the number of bits required to encode the quantization index for both
+ channels in each subband. If we're above the jsbound, then pretend we only
+ have one channel */
+ for (sb = 0; sb < jsbound; ++sb)
+ bbal += nch * nbal[ line[tablenum][sb] ]; //(*alloc)[sb][0].bits;
+ for (sb = jsbound; sb < sblimit; ++sb)
+ bbal += nbal[ line[tablenum][sb] ]; //(*alloc)[sb][0].bits;
+ req_bits = banc + bbal + berr;
+
+ for (sb = 0; sb < sblimit; ++sb)
+ for (ch = 0; ch < ((sb < jsbound) ? nch : 1); ++ch) {
+ int thisline = line[tablenum][sb];
+
+ /* How many possible steps are there to choose from ? */
+ maxAlloc = (1 << nbal[ line[tablenum][sb] ]) -1; //(*alloc)[sb][0].bits) - 1;
+ sel_bits = sc_bits = smp_bits = 0;
+ /* Keep choosing the next number of steps (and hence our SNR value)
+ until we have the required MNR value */
+ for (ba = 0; ba < maxAlloc - 1; ++ba) {
+ int thisstep_index = step_index[thisline][ba];
+ if ((SNR[thisstep_index] - SMR[ch][sb]) >= min_mnr)
+ break; /* we found enough bits */
+ }
+ if (nch == 2 && sb >= jsbound) /* check other JS channel */
+ for (; ba < maxAlloc - 1; ++ba) {
+ int thisstep_index = step_index[thisline][ba];
+ if ((SNR[thisstep_index] - SMR[1-ch][sb]) >= min_mnr)
+ break;
+ }
+ if (ba > 0) {
+ //smp_bits = SCALE_BLOCK * ((*alloc)[sb][ba].group * (*alloc)[sb][ba].bits);
+ int thisstep_index = step_index[thisline][ba];
+ smp_bits = SCALE_BLOCK * group[thisstep_index] * bits[thisstep_index];
+ /* scale factor bits required for subband */
+ sel_bits = 2;
+ sc_bits = 6 * sfsPerScfsi[scfsi[ch][sb]];
+ if (nch == 2 && sb >= jsbound) {
+ /* each new js sb has L+R scfsis */
+ sel_bits += 2;
+ sc_bits += 6 * sfsPerScfsi[scfsi[1 - ch][sb]];
+ }
+ req_bits += smp_bits + sel_bits + sc_bits;
+ }
+ bit_alloc[ch][sb] = ba;
+ }
+ return req_bits;
+}
+
+
+
+/************************************************************************
+*
+* main_bit_allocation (Layer II)
+*
+* PURPOSE:For joint stereo mode, determines which of the 4 joint
+* stereo modes is needed. Then calls *_a_bit_allocation(), which
+* allocates bits for each of the subbands until there are no more bits
+* left, or the MNR is at the noise/no_noise threshold.
+*
+* SEMANTICS:
+*
+* For joint stereo mode, joint stereo is changed to stereo if
+* there are enough bits to encode stereo at or better than the
+* no-noise threshold (NOISY_MIN_MNR). Otherwise, the system
+* iteratively allocates less bits by using joint stereo until one
+* of the following occurs:
+* - there are no more noisy subbands (MNR >= NOISY_MIN_MNR)
+* - mode_ext has been reduced to 0, which means that all but the
+* lowest 4 subbands have been converted from stereo to joint
+* stereo, and no more subbands may be converted
+*
+* This function calls *_bits_for_nonoise() and *_a_bit_allocation().
+*
+************************************************************************/
+void main_bit_allocation_new (double SMR[2][SBLIMIT],
+ unsigned int scfsi[2][SBLIMIT],
+ unsigned int bit_alloc[2][SBLIMIT], int *adb,
+ frame_info * frame, options * glopts)
+{
+ int noisy_sbs;
+ int mode, mode_ext, lay;
+ int rq_db; /* av_db = *adb; Not Used MFC Nov 99 */
+
+ /* these are the tables which specify the limits within which the VBR can vary
+ You can't vary outside these ranges, otherwise a new alloc table would have to
+ be loaded in the middle of encoding. This VBR hack is dodgy - the standard
+ says that LayerII decoders don't have to support a variable bitrate, but Layer3
+ decoders must do so. Hence, it is unlikely that a compliant layer2 decoder would be
+ written to dynmically change allocation tables. *BUT* a layer3 encoder might handle it
+ by default, meaning we could switch tables mid-encode and enjoy a wider range of bitrates
+ for the VBR encoding.
+ None of this needs to be done for LSF, since there is only *one* possible alloc table in LSF
+ MFC Feb 2003 */
+ int vbrlimits[2][3][2] = {
+ /* MONO */
+ { /* 44 */ {6, 10},
+ /* 48 */ {3, 10},
+ /* 32 */ {6, 10}},
+ /* STEREO */
+ { /* 44 */ {10, 14},
+ /* 48 */ {7, 14},
+ /* 32 */ {10, 14}}
+ };
+
+ static int init = 0;
+ static int lower = 10, upper = 10;
+ static int bitrateindextobits[15] =
+ { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ int guessindex = 0;
+
+ if (init == 0) {
+ int nch = 2;
+ int sfreq;
+ frame_header *header = frame->header;
+ init++;
+ if (header->version == 0) {
+ /* LSF: so can use any bitrate index from 1->15 */
+ lower = 1;
+ upper = 14;
+ } else {
+ if (frame->actual_mode == MPG_MD_MONO)
+ nch = 1;
+ sfreq = header->sampling_frequency;
+ lower = vbrlimits[nch-1][sfreq][0];
+ upper = vbrlimits[nch-1][sfreq][1];
+ }
+ if (glopts->verbosity > 2)
+ fprintf (stdout, "VBR bitrate index limits [%i -> %i]\n", lower, upper);
+
+ {
+ /* set up a conversion table for bitrateindex->bits for this version/sampl freq
+ This will be used to find the best bitrate to cope with the number of bits that
+ are needed (as determined by VBR_bits_for_nonoise) */
+ int brindex;
+ frame_header *header = frame->header;
+ for (brindex = lower; brindex <= upper; brindex++) {
+ bitrateindextobits[brindex] =
+ (int) (1152.0 / s_freq[header->version][header->sampling_frequency]) *
+ ((double) bitrate[header->version][brindex]);
+ }
+ }
+
+ }
+
+ if ((mode = frame->actual_mode) == MPG_MD_JOINT_STEREO) {
+ frame->header->mode = MPG_MD_STEREO;
+ frame->header->mode_ext = 0;
+ frame->jsbound = frame->sblimit;
+ if ((rq_db = bits_for_nonoise_new (SMR, scfsi, frame, 0, bit_alloc)) > *adb) {
+ frame->header->mode = MPG_MD_JOINT_STEREO;
+ mode_ext = 4; /* 3 is least severe reduction */
+ lay = frame->header->lay;
+ do {
+ --mode_ext;
+ frame->jsbound = js_bound (mode_ext);
+ rq_db = bits_for_nonoise_new (SMR, scfsi, frame, 0, bit_alloc);
+ }
+ while ((rq_db > *adb) && (mode_ext > 0));
+ frame->header->mode_ext = mode_ext;
+ } /* well we either eliminated noisy sbs or mode_ext == 0 */
+ }
+
+ /* decide on which bit allocation method to use */
+ if (glopts->vbr == FALSE) {
+ /* Just do the old bit allocation method */
+ noisy_sbs = a_bit_allocation_new (SMR, scfsi, bit_alloc, adb, frame);
+ } else {
+ /* do the VBR bit allocation method */
+ frame->header->bitrate_index = lower;
+ *adb = available_bits (frame->header, glopts);
+ {
+ int brindex;
+ int found = FALSE;
+
+ /* Work out how many bits are needed for there to be no noise (ie all MNR > VBRLEVEL) */
+ int req =
+ bits_for_nonoise_new (SMR, scfsi, frame, glopts->vbrlevel, bit_alloc);
+
+ /* Look up this value in the bitrateindextobits table to find what bitrate we should use for
+ this frame */
+ for (brindex = lower; brindex <= upper; brindex++) {
+ if (bitrateindextobits[brindex] > req) {
+ /* this method always *overestimates* the bits that are needed
+ i.e. it will usually guess right but
+ when it's wrong it'll guess a higher bitrate than actually required.
+ e.g. on "messages from earth" track 6, the guess was
+ wrong on 75/36341 frames. each time it guessed higher.
+ MFC Feb 2003 */
+ guessindex = brindex;
+ found = TRUE;
+ break;
+ }
+ }
+ /* Just for sanity */
+ if (found == FALSE)
+ guessindex = upper;
+ }
+
+ frame->header->bitrate_index = guessindex;
+ *adb = available_bits (frame->header, glopts);
+
+ /* update the statistics */
+ vbrstats_new[frame->header->bitrate_index]++;
+
+ if (glopts->verbosity > 2) {
+ /* print out the VBR stats every 1000th frame */
+ static int count = 0;
+ int i;
+ if ((count++ % 1000) == 0) {
+ for (i = 1; i < 15; i++)
+ fprintf (stdout, "%4i ", vbrstats_new[i]);
+ fprintf (stdout, "\n");
+ }
+
+ /* Print out *every* frames bitrateindex, bits required, and bits available at this bitrate */
+ if (glopts->verbosity > 5)
+ fprintf (stdout,
+ "> bitrate index %2i has %i bits available to encode the %i bits\n",
+ frame->header->bitrate_index, *adb,
+ bits_for_nonoise_new (SMR, scfsi, frame,
+ glopts->vbrlevel, bit_alloc));
+
+ }
+
+ noisy_sbs =
+ VBR_bit_allocation_new (SMR, scfsi, bit_alloc, adb, frame, glopts);
+ }
+}
+
+void VBR_maxmnr_new (double mnr[2][SBLIMIT], char used[2][SBLIMIT], int sblimit,
+ int nch, int *min_sb, int *min_ch, options * glopts)
+{
+ int sb, ch;
+ double small;
+
+ small = 999999.0;
+ *min_sb = -1;
+ *min_ch = -1;
+
+#define NEWBITx
+#ifdef NEWBIT
+ /* Keep going until all subbands have reached the MNR level that we specified */
+ for (ch=0;ch<nch;ch++)
+ for (sb=0;sb<sblimit;sb++)
+ if (mnr[ch][sb] < glopts->vbrlevel) {
+ *min_sb = sb;
+ *min_ch = ch;
+ //fprintf(stdout,".");
+ //fflush(stdout);
+ return;
+ }
+#endif
+
+ /* Then start adding bits to whichever is the min MNR */
+ for (ch = 0; ch < nch; ++ch)
+ for (sb = 0; sb < sblimit; sb++)
+ if (used[ch][sb] != 2 && small > mnr[ch][sb]) {
+ small = mnr[ch][sb];
+ *min_sb = sb;
+ *min_ch = ch;
+ }
+ //fprintf(stdout,"Min sb: %i\n",*min_sb);
+}
+/********************
+MFC Feb 2003
+VBR_bit_allocation is different to the normal a_bit_allocation in that
+it is known beforehand that there are definitely enough bits to do what we
+have to - i.e. a bitrate was specificially chosen in main_bit_allocation so
+that we have enough bits to encode what we have to.
+This function should take that into account and just greedily assign
+the bits, rather than fussing over the minimum MNR subband - we know
+each subband gets its required bits, why quibble?
+This function doesn't chew much CPU, so I haven't made any attempt
+to do this yet.
+*********************/
+int VBR_bit_allocation_new (double SMR[2][SBLIMIT],
+ unsigned int scfsi[2][SBLIMIT],
+ unsigned int bit_alloc[2][SBLIMIT], int *adb,
+ frame_info * frame, options *glopts)
+{
+ int sb, min_ch, min_sb, oth_ch, ch, increment, scale, seli, ba;
+ int bspl, bscf, bsel, ad, bbal = 0;
+ double mnr[2][SBLIMIT];
+ char used[2][SBLIMIT];
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int jsbound = frame->jsbound;
+ //al_table *alloc = frame->alloc;
+ static char init = 0;
+ static int banc = 32, berr = 0;
+ static int sfsPerScfsi[] = { 3, 2, 1, 2 }; /* lookup # sfs per scfsi */
+
+ int thisstep_index;
+
+ if (!init) {
+ init = 1;
+ if (frame->header->error_protection)
+ berr = 16; /* added 92-08-11 shn */
+ }
+
+ /* No need to worry about jsbound here as JS is disabled for VBR mode */
+ for (sb = 0; sb < sblimit; sb++)
+ bbal += nch * nbal[ line[tablenum][sb] ];
+ *adb -= bbal + berr + banc;
+ ad = *adb;
+
+ for (sb = 0; sb < sblimit; sb++)
+ for (ch = 0; ch < nch; ch++) {
+ mnr[ch][sb] = SNR[0] - SMR[ch][sb];
+ bit_alloc[ch][sb] = 0;
+ used[ch][sb] = 0;
+ }
+ bspl = bscf = bsel = 0;
+
+ do {
+ /* locate the subband with minimum SMR */
+ VBR_maxmnr_new (mnr, used, sblimit, nch, &min_sb, &min_ch, glopts);
+
+ if (min_sb > -1) { /* there was something to find */
+ int thisline = line[tablenum][min_sb]; {
+ /* find increase in bit allocation in subband [min] */
+ int nextstep_index = step_index[thisline][bit_alloc[min_ch][min_sb]+1];
+ increment = SCALE_BLOCK * group[nextstep_index] * bits[nextstep_index];
+ }
+ if (used[min_ch][min_sb]) {
+ /* If we've already increased the limit on this ch/sb, then
+ subtract the last thing that we added */
+ thisstep_index = step_index[thisline][bit_alloc[min_ch][min_sb]];
+ increment -= SCALE_BLOCK * group[thisstep_index] * bits[thisstep_index];
+ }
+
+ /* scale factor bits required for subband [min] */
+ oth_ch = 1 - min_ch; /* above js bound, need both chans */
+ if (used[min_ch][min_sb])
+ scale = seli = 0;
+ else { /* this channel had no bits or scfs before */
+ seli = 2;
+ scale = 6 * sfsPerScfsi[scfsi[min_ch][min_sb]];
+ if (nch == 2 && min_sb >= jsbound) {
+ /* each new js sb has L+R scfsis */
+ seli += 2;
+ scale += 6 * sfsPerScfsi[scfsi[oth_ch][min_sb]];
+ }
+ }
+
+ /* check to see enough bits were available for */
+ /* increasing resolution in the minimum band */
+ if (ad >= bspl + bscf + bsel + seli + scale + increment) {
+ /* Then there are enough bits to have another go at allocating */
+ ba = ++bit_alloc[min_ch][min_sb]; /* next up alloc */
+ bspl += increment; /* bits for subband sample */
+ bscf += scale; /* bits for scale factor */
+ bsel += seli; /* bits for scfsi code */
+ used[min_ch][min_sb] = 1; /* subband has bits */
+ thisstep_index = step_index[thisline][ba];
+ mnr[min_ch][min_sb] = SNR[thisstep_index] - SMR[min_ch][min_sb];
+ /* Check if this min_sb subband has been fully allocated max bits */
+ if (ba >= (1 << nbal[ line[tablenum][min_sb] ]) -1 ) //(*alloc)[min_sb][0].bits) - 1)
+ used[min_ch][min_sb] = 2; /* don't let this sb get any more bits */
+ } else
+ used[min_ch][min_sb] = 2; /* can't increase this alloc */
+ }
+ }
+ while (min_sb > -1); /* until could find no channel */
+
+ /* Calculate the number of bits left */
+ ad -= bspl + bscf + bsel;
+ *adb = ad;
+ for (ch = 0; ch < nch; ch++)
+ for (sb = sblimit; sb < SBLIMIT; sb++)
+ bit_alloc[ch][sb] = 0;
+
+ return 0;
+}
+
+
+
+/************************************************************************
+*
+* a_bit_allocation (Layer II)
+*
+* PURPOSE:Adds bits to the subbands with the lowest mask-to-noise
+* ratios, until the maximum number of bits for the subband has
+* been allocated.
+*
+* SEMANTICS:
+* 1. Find the subband and channel with the smallest MNR (#min_sb#,
+* and #min_ch#)
+* 2. Calculate the increase in bits needed if we increase the bit
+* allocation to the next higher level
+* 3. If there are enough bits available for increasing the resolution
+* in #min_sb#, #min_ch#, and the subband has not yet reached its
+* maximum allocation, update the bit allocation, MNR, and bits
+ available accordingly
+* 4. Repeat until there are no more bits left, or no more available
+* subbands. (A subband is still available until the maximum
+* number of bits for the subband has been allocated, or there
+* aren't enough bits to go to the next higher resolution in the
+ subband.)
+*
+************************************************************************/
+
+void maxmnr_new (double mnr[2][SBLIMIT], char used[2][SBLIMIT], int sblimit,
+ int nch, int *min_sb, int *min_ch)
+{
+ int sb, ch;
+ double small;
+
+ small = 999999.0;
+ *min_sb = -1;
+ *min_ch = -1;
+ for (ch = 0; ch < nch; ++ch)
+ for (sb = 0; sb < sblimit; sb++)
+ if (used[ch][sb] != 2 && small > mnr[ch][sb]) {
+ small = mnr[ch][sb];
+ *min_sb = sb;
+ *min_ch = ch;
+ }
+}
+int a_bit_allocation_new (double SMR[2][SBLIMIT],
+ unsigned int scfsi[2][SBLIMIT],
+ unsigned int bit_alloc[2][SBLIMIT], int *adb,
+ frame_info * frame)
+{
+ int sb, min_ch, min_sb, oth_ch, ch, increment, scale, seli, ba;
+ int bspl, bscf, bsel, ad, bbal = 0;
+ double mnr[2][SBLIMIT];
+ char used[2][SBLIMIT];
+ int nch = frame->nch;
+ int sblimit = frame->sblimit;
+ int jsbound = frame->jsbound;
+ //al_table *alloc = frame->alloc;
+ static char init = 0;
+ static int banc = 32, berr = 0;
+ static int sfsPerScfsi[] = { 3, 2, 1, 2 }; /* lookup # sfs per scfsi */
+
+ int thisstep_index;
+
+ if (!init) {
+ init = 1;
+ if (frame->header->error_protection)
+ berr = 16; /* added 92-08-11 shn */
+ }
+
+ for (sb = 0; sb < jsbound; sb++)
+ bbal += nch * nbal[ line[tablenum][sb] ]; //(*alloc)[sb][0].bits;
+ for (sb = jsbound; sb < sblimit; sb++)
+ bbal += nbal[ line[tablenum][sb] ]; //(*alloc)[sb][0].bits;
+ *adb -= bbal + berr + banc;
+ ad = *adb;
+
+ for (sb = 0; sb < sblimit; sb++)
+ for (ch = 0; ch < nch; ch++) {
+ mnr[ch][sb] = SNR[0] - SMR[ch][sb];
+ bit_alloc[ch][sb] = 0;
+ used[ch][sb] = 0;
+ }
+ bspl = bscf = bsel = 0;
+
+ do {
+ /* locate the subband with minimum SMR */
+ maxmnr_new (mnr, used, sblimit, nch, &min_sb, &min_ch);
+
+ if (min_sb > -1) { /* there was something to find */
+ int thisline = line[tablenum][min_sb]; {
+ /* find increase in bit allocation in subband [min] */
+ int nextstep_index = step_index[thisline][bit_alloc[min_ch][min_sb]+1];
+ increment = SCALE_BLOCK * group[nextstep_index] * bits[nextstep_index];
+ }
+ if (used[min_ch][min_sb]) {
+ /* If we've already increased the limit on this ch/sb, then
+ subtract the last thing that we added */
+ thisstep_index = step_index[thisline][bit_alloc[min_ch][min_sb]];
+ increment -= SCALE_BLOCK * group[thisstep_index] * bits[thisstep_index];
+ }
+
+ /* scale factor bits required for subband [min] */
+ oth_ch = 1 - min_ch; /* above js bound, need both chans */
+ if (used[min_ch][min_sb])
+ scale = seli = 0;
+ else { /* this channel had no bits or scfs before */
+ seli = 2;
+ scale = 6 * sfsPerScfsi[scfsi[min_ch][min_sb]];
+ if (nch == 2 && min_sb >= jsbound) {
+ /* each new js sb has L+R scfsis */
+ seli += 2;
+ scale += 6 * sfsPerScfsi[scfsi[oth_ch][min_sb]];
+ }
+ }
+
+ /* check to see enough bits were available for */
+ /* increasing resolution in the minimum band */
+ if (ad >= bspl + bscf + bsel + seli + scale + increment) {
+ /* Then there are enough bits to have another go at allocating */
+ ba = ++bit_alloc[min_ch][min_sb]; /* next up alloc */
+ bspl += increment; /* bits for subband sample */
+ bscf += scale; /* bits for scale factor */
+ bsel += seli; /* bits for scfsi code */
+ used[min_ch][min_sb] = 1; /* subband has bits */
+ thisstep_index = step_index[thisline][ba];
+ mnr[min_ch][min_sb] = SNR[thisstep_index] - SMR[min_ch][min_sb];
+ /* Check if this min_sb subband has been fully allocated max bits */
+ if (ba >= (1 << nbal[ line[tablenum][min_sb] ]) -1 ) //(*alloc)[min_sb][0].bits) - 1)
+ used[min_ch][min_sb] = 2; /* don't let this sb get any more bits */
+ } else
+ used[min_ch][min_sb] = 2; /* can't increase this alloc */
+
+ if (min_sb >= jsbound && nch == 2) {
+ /* above jsbound, alloc applies L+R */
+ ba = bit_alloc[oth_ch][min_sb] = bit_alloc[min_ch][min_sb];
+ used[oth_ch][min_sb] = used[min_ch][min_sb];
+ thisstep_index = step_index[thisline][ba];
+ mnr[oth_ch][min_sb] = SNR[thisstep_index] - SMR[oth_ch][min_sb];
+ //mnr[oth_ch][min_sb] = SNR[(*alloc)[min_sb][ba].quant + 1] - SMR[oth_ch][min_sb];
+ }
+
+ }
+ }
+ while (min_sb > -1); /* until could find no channel */
+
+ /* Calculate the number of bits left */
+ ad -= bspl + bscf + bsel;
+ *adb = ad;
+ for (ch = 0; ch < nch; ch++)
+ for (sb = sblimit; sb < SBLIMIT; sb++)
+ bit_alloc[ch][sb] = 0;
+
+ return 0;
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-16 02:32:53 +0000