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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 576 | serge | 1 | /* |
| 2 | layer2.c: the layer 2 decoder, root of mpg123 |
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| 3 | |||
| 4 | copyright 1994-2006 by the mpg123 project - free software under the terms of the LGPL 2.1 |
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| 5 | see COPYING and AUTHORS files in distribution or http://mpg123.de |
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| 6 | initially written by Michael Hipp |
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| 7 | |||
| 8 | mpg123 started as mp2 decoder a long time ago... |
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| 9 | */ |
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| 10 | |||
| 11 | #include "mpg123.h" |
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| 12 | #include "l2tables.h" |
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| 13 | |||
| 14 | static int grp_3tab[32 * 3] = { 0, }; /* used: 27 */ |
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| 15 | static int grp_5tab[128 * 3] = { 0, }; /* used: 125 */ |
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| 16 | static int grp_9tab[1024 * 3] = { 0, }; /* used: 729 */ |
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| 17 | |||
| 18 | real muls[27][64]; /* also used by layer 1 */ |
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| 19 | |||
| 20 | void init_layer2(void) |
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| 21 | { |
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| 22 | static double mulmul[27] = { |
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| 23 | 0.0 , -2.0/3.0 , 2.0/3.0 , |
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| 24 | 2.0/7.0 , 2.0/15.0 , 2.0/31.0, 2.0/63.0 , 2.0/127.0 , 2.0/255.0 , |
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| 25 | 2.0/511.0 , 2.0/1023.0 , 2.0/2047.0 , 2.0/4095.0 , 2.0/8191.0 , |
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| 26 | 2.0/16383.0 , 2.0/32767.0 , 2.0/65535.0 , |
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| 27 | -4.0/5.0 , -2.0/5.0 , 2.0/5.0, 4.0/5.0 , |
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| 28 | -8.0/9.0 , -4.0/9.0 , -2.0/9.0 , 2.0/9.0 , 4.0/9.0 , 8.0/9.0 }; |
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| 29 | static int base[3][9] = { |
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| 30 | { 1 , 0, 2 , } , |
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| 31 | { 17, 18, 0 , 19, 20 , } , |
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| 32 | { 21, 1, 22, 23, 0, 24, 25, 2, 26 } }; |
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| 33 | int i,j,k,l,len; |
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| 34 | real *table; |
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| 35 | static int tablen[3] = { 3 , 5 , 9 }; |
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| 36 | static int *itable,*tables[3] = { grp_3tab , grp_5tab , grp_9tab }; |
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| 37 | |||
| 38 | for(i=0;i<3;i++) |
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| 39 | { |
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| 40 | itable = tables[i]; |
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| 41 | len = tablen[i]; |
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| 42 | for(j=0;j |
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| 43 | for(k=0;k |
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| 44 | for(l=0;l |
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| 45 | { |
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| 46 | *itable++ = base[i][l]; |
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| 47 | *itable++ = base[i][k]; |
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| 48 | *itable++ = base[i][j]; |
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| 49 | } |
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| 50 | } |
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| 51 | |||
| 52 | for(k=0;k<27;k++) |
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| 53 | { |
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| 54 | double m=mulmul[k]; |
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| 55 | table = muls[k]; |
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| 56 | #ifdef USE_MMX |
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| 57 | if(!param.down_sample) |
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| 58 | for(j=3,i=0;i<63;i++,j--) |
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| 59 | *table++ = 16384 * m * pow(2.0,(double) j / 3.0); |
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| 60 | else |
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| 61 | #endif |
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| 62 | for(j=3,i=0;i<63;i++,j--) |
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| 63 | *table++ = m * pow_test(2.0,(double) j / 3.0); |
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| 64 | *table++ = 0.0; |
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| 65 | } |
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| 66 | } |
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| 67 | |||
| 68 | |||
| 69 | void II_step_one(unsigned int *bit_alloc,int *scale,struct frame *fr) |
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| 70 | { |
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| 71 | int stereo = fr->stereo-1; |
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| 72 | int sblimit = fr->II_sblimit; |
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| 73 | int jsbound = fr->jsbound; |
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| 74 | int sblimit2 = fr->II_sblimit< |
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| 75 | struct al_table *alloc1 = fr->alloc; |
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| 76 | int i; |
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| 77 | static unsigned int scfsi_buf[64]; |
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| 78 | unsigned int *scfsi,*bita; |
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| 79 | int sc,step; |
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| 80 | |||
| 81 | bita = bit_alloc; |
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| 82 | if(stereo) |
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| 83 | { |
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| 84 | for (i=jsbound;i;i--,alloc1+=(1< |
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| 85 | { |
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| 86 | *bita++ = (char) getbits(step=alloc1->bits); |
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| 87 | *bita++ = (char) getbits(step); |
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| 88 | } |
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| 89 | for (i=sblimit-jsbound;i;i--,alloc1+=(1< |
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| 90 | { |
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| 91 | bita[0] = (char) getbits(step=alloc1->bits); |
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| 92 | bita[1] = bita[0]; |
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| 93 | bita+=2; |
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| 94 | } |
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| 95 | bita = bit_alloc; |
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| 96 | scfsi=scfsi_buf; |
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| 97 | for (i=sblimit2;i;i--) |
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| 98 | if (*bita++) |
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| 99 | *scfsi++ = (char) getbits_fast(2); |
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| 100 | } |
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| 101 | else /* mono */ |
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| 102 | { |
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| 103 | for (i=sblimit;i;i--,alloc1+=(1< |
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| 104 | *bita++ = (char) getbits(step=alloc1->bits); |
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| 105 | bita = bit_alloc; |
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| 106 | scfsi=scfsi_buf; |
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| 107 | for (i=sblimit;i;i--) |
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| 108 | if (*bita++) |
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| 109 | *scfsi++ = (char) getbits_fast(2); |
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| 110 | } |
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| 111 | |||
| 112 | bita = bit_alloc; |
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| 113 | scfsi=scfsi_buf; |
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| 114 | for (i=sblimit2;i;i--) |
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| 115 | if (*bita++) |
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| 116 | switch (*scfsi++) |
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| 117 | { |
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| 118 | case 0: |
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| 119 | *scale++ = getbits_fast(6); |
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| 120 | *scale++ = getbits_fast(6); |
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| 121 | *scale++ = getbits_fast(6); |
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| 122 | break; |
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| 123 | case 1 : |
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| 124 | *scale++ = sc = getbits_fast(6); |
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| 125 | *scale++ = sc; |
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| 126 | *scale++ = getbits_fast(6); |
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| 127 | break; |
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| 128 | case 2: |
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| 129 | *scale++ = sc = getbits_fast(6); |
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| 130 | *scale++ = sc; |
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| 131 | *scale++ = sc; |
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| 132 | break; |
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| 133 | default: /* case 3 */ |
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| 134 | *scale++ = getbits_fast(6); |
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| 135 | *scale++ = sc = getbits_fast(6); |
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| 136 | *scale++ = sc; |
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| 137 | break; |
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| 138 | } |
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| 139 | |||
| 140 | } |
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| 141 | |||
| 142 | void II_step_two(unsigned int *bit_alloc,real fraction[2][4][SBLIMIT],int *scale,struct frame *fr,int x1) |
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| 143 | { |
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| 144 | int i,j,k,ba; |
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| 145 | int stereo = fr->stereo; |
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| 146 | int sblimit = fr->II_sblimit; |
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| 147 | int jsbound = fr->jsbound; |
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| 148 | struct al_table *alloc2,*alloc1 = fr->alloc; |
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| 149 | unsigned int *bita=bit_alloc; |
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| 150 | int d1,step; |
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| 151 | |||
| 152 | for (i=0;i |
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| 153 | { |
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| 154 | step = alloc1->bits; |
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| 155 | for (j=0;j |
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| 156 | { |
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| 157 | if ( (ba=*bita++) ) |
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| 158 | { |
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| 159 | k=(alloc2 = alloc1+ba)->bits; |
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| 160 | if( (d1=alloc2->d) < 0) |
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| 161 | { |
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| 162 | real cm=muls[k][scale[x1]]; |
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| 163 | fraction[j][0][i] = ((real) ((int)getbits(k) + d1)) * cm; |
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| 164 | fraction[j][1][i] = ((real) ((int)getbits(k) + d1)) * cm; |
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| 165 | fraction[j][2][i] = ((real) ((int)getbits(k) + d1)) * cm; |
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| 166 | } |
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| 167 | else |
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| 168 | { |
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| 169 | static int *table[] = { 0,0,0,grp_3tab,0,grp_5tab,0,0,0,grp_9tab }; |
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| 170 | unsigned int idx,*tab,m=scale[x1]; |
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| 171 | idx = (unsigned int) getbits(k); |
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| 172 | tab = (unsigned int *) (table[d1] + idx + idx + idx); |
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| 173 | fraction[j][0][i] = muls[*tab++][m]; |
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| 174 | fraction[j][1][i] = muls[*tab++][m]; |
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| 175 | fraction[j][2][i] = muls[*tab][m]; |
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| 176 | } |
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| 177 | scale+=3; |
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| 178 | } |
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| 179 | else |
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| 180 | fraction[j][0][i] = fraction[j][1][i] = fraction[j][2][i] = 0.0; |
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| 181 | } |
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| 182 | } |
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| 183 | |||
| 184 | for (i=jsbound;i |
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| 185 | { |
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| 186 | step = alloc1->bits; |
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| 187 | bita++; /* channel 1 and channel 2 bitalloc are the same */ |
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| 188 | if ( (ba=*bita++) ) |
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| 189 | { |
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| 190 | k=(alloc2 = alloc1+ba)->bits; |
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| 191 | if( (d1=alloc2->d) < 0) |
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| 192 | { |
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| 193 | real cm; |
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| 194 | cm=muls[k][scale[x1+3]]; |
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| 195 | fraction[1][0][i] = (fraction[0][0][i] = (real) ((int)getbits(k) + d1) ) * cm; |
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| 196 | fraction[1][1][i] = (fraction[0][1][i] = (real) ((int)getbits(k) + d1) ) * cm; |
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| 197 | fraction[1][2][i] = (fraction[0][2][i] = (real) ((int)getbits(k) + d1) ) * cm; |
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| 198 | cm=muls[k][scale[x1]]; |
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| 199 | fraction[0][0][i] *= cm; fraction[0][1][i] *= cm; fraction[0][2][i] *= cm; |
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| 200 | } |
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| 201 | else |
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| 202 | { |
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| 203 | static int *table[] = { 0,0,0,grp_3tab,0,grp_5tab,0,0,0,grp_9tab }; |
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| 204 | unsigned int idx,*tab,m1,m2; |
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| 205 | m1 = scale[x1]; m2 = scale[x1+3]; |
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| 206 | idx = (unsigned int) getbits(k); |
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| 207 | tab = (unsigned int *) (table[d1] + idx + idx + idx); |
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| 208 | fraction[0][0][i] = muls[*tab][m1]; fraction[1][0][i] = muls[*tab++][m2]; |
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| 209 | fraction[0][1][i] = muls[*tab][m1]; fraction[1][1][i] = muls[*tab++][m2]; |
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| 210 | fraction[0][2][i] = muls[*tab][m1]; fraction[1][2][i] = muls[*tab][m2]; |
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| 211 | } |
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| 212 | scale+=6; |
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| 213 | } |
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| 214 | else { |
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| 215 | fraction[0][0][i] = fraction[0][1][i] = fraction[0][2][i] = |
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| 216 | fraction[1][0][i] = fraction[1][1][i] = fraction[1][2][i] = 0.0; |
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| 217 | } |
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| 218 | /* |
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| 219 | should we use individual scalefac for channel 2 or |
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| 220 | is the current way the right one , where we just copy channel 1 to |
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| 221 | channel 2 ?? |
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| 222 | The current 'strange' thing is, that we throw away the scalefac |
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| 223 | values for the second channel ...!! |
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| 224 | -> changed .. now we use the scalefac values of channel one !! |
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| 225 | */ |
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| 226 | } |
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| 227 | |||
| 228 | if(sblimit > (fr->down_sample_sblimit) ) |
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| 229 | sblimit = fr->down_sample_sblimit; |
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| 230 | |||
| 231 | for(i=sblimit;i |
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| 232 | for (j=0;j |
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| 233 | fraction[j][0][i] = fraction[j][1][i] = fraction[j][2][i] = 0.0; |
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| 234 | |||
| 235 | } |
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| 236 | |||
| 237 | static void II_select_table(struct frame *fr) |
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| 238 | { |
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| 239 | static int translate[3][2][16] = |
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| 240 | { { { 0,2,2,2,2,2,2,0,0,0,1,1,1,1,1,0 } , |
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| 241 | { 0,2,2,0,0,0,1,1,1,1,1,1,1,1,1,0 } } , |
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| 242 | { { 0,2,2,2,2,2,2,0,0,0,0,0,0,0,0,0 } , |
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| 243 | { 0,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0 } } , |
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| 244 | { { 0,3,3,3,3,3,3,0,0,0,1,1,1,1,1,0 } , |
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| 245 | { 0,3,3,0,0,0,1,1,1,1,1,1,1,1,1,0 } } }; |
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| 246 | |||
| 247 | int table,sblim; |
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| 248 | static struct al_table *tables[5] = |
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| 249 | { alloc_0, alloc_1, alloc_2, alloc_3 , alloc_4 }; |
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| 250 | static int sblims[5] = { 27 , 30 , 8, 12 , 30 }; |
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| 251 | |||
| 252 | if(fr->sampling_frequency >= 3) /* Or equivalent: (fr->lsf == 1) */ |
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| 253 | table = 4; |
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| 254 | else |
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| 255 | table = translate[fr->sampling_frequency][2-fr->stereo][fr->bitrate_index]; |
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| 256 | sblim = sblims[table]; |
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| 257 | |||
| 258 | fr->alloc = tables[table]; |
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| 259 | fr->II_sblimit = sblim; |
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| 260 | } |
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| 261 | |||
| 262 | |||
| 263 | int do_layer2(struct frame *fr,byte *pcm_sample,int *pcm_point) |
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| 264 | { |
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| 265 | int clip=0; |
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| 266 | int i,j; |
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| 267 | int stereo = fr->stereo; |
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| 268 | real fraction[2][4][SBLIMIT]; /* pick_table clears unused subbands */ |
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| 269 | unsigned int bit_alloc[64]; |
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| 270 | int scale[192]; |
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| 271 | int single = fr->single; |
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| 272 | |||
| 273 | II_select_table(fr); |
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| 274 | fr->jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ? |
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| 275 | (fr->mode_ext<<2)+4 : fr->II_sblimit; |
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| 276 | |||
| 277 | if (fr->jsbound > fr->II_sblimit) { |
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| 278 | fr->jsbound=fr->II_sblimit; |
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| 279 | } |
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| 280 | |||
| 281 | if(stereo == 1 || single == 3) |
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| 282 | single = 0; |
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| 283 | |||
| 284 | II_step_one(bit_alloc, scale, fr); |
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| 285 | |||
| 286 | for (i=0;i |
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| 287 | { |
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| 288 | II_step_two(bit_alloc,fraction,scale,fr,i>>2); |
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| 289 | for (j=0;j<3;j++) |
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| 290 | { |
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| 291 | if(single >= 0) |
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| 292 | { |
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| 293 | clip += (fr->synth_mono) (fraction[single][j],pcm_sample,pcm_point); |
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| 294 | } |
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| 295 | else { |
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| 296 | int p1=*pcm_point; |
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| 297 | clip += (fr->synth) (fraction[0][j],0,pcm_sample, &p1); |
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| 298 | clip += (fr->synth) (fraction[1][j],1,pcm_sample,pcm_point); |
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| 299 | } |
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| 300 | } |
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| 301 | } |
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| 302 | |||
| 303 | return clip; |
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| 304 | } |
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| 305 | |||
| 306 |