static int decode_init(AVCodecContext * avctx) { MPADecodeContext *s = avctx->priv_data; static int init=0; int i, j, k; #if defined(USE_HIGHPRECISION) && defined(CONFIG_AUDIO_NONSHORT) avctx->sample_fmt= SAMPLE_FMT_S32; #else avctx->sample_fmt= SAMPLE_FMT_S16; #endif if(avctx->antialias_algo != FF_AA_FLOAT) s->compute_antialias= compute_antialias_integer; else s->compute_antialias= compute_antialias_float; if (!init && !avctx->parse_only) { /* scale factors table for layer 1/2 */ for(i=0;i<64;i++) { int shift, mod; /* 1.0 (i = 3) is normalized to 2 ^ FRAC_BITS */ shift = (i / 3); mod = i % 3; scale_factor_modshift[i] = mod | (shift << 2); } /* scale factor multiply for layer 1 */ for(i=0;i<15;i++) { int n, norm; n = i + 2; norm = ((int64_t_C(1) << n) * FRAC_ONE) / ((1 << n) - 1); scale_factor_mult[i][0] = MULL(FIXR(1.0 * 2.0), norm); scale_factor_mult[i][1] = MULL(FIXR(0.7937005259 * 2.0), norm); scale_factor_mult[i][2] = MULL(FIXR(0.6299605249 * 2.0), norm); dprintf("%d: norm=%x s=%x %x %x\n", i, norm, scale_factor_mult[i][0], scale_factor_mult[i][1], scale_factor_mult[i][2]); } ff_mpa_synth_init(window); /* huffman decode tables */ for(i=1;i<16;i++) { const HuffTable *h = &mpa_huff_tables[i]; int xsize, x, y; unsigned int n; uint8_t tmp_bits [256]; uint16_t tmp_codes[256]; memset(tmp_bits , 0, sizeof(tmp_bits )); memset(tmp_codes, 0, sizeof(tmp_codes)); xsize = h->xsize; n = xsize * xsize; j = 0; for(x=0;x<xsize;x++) { for(y=0;y<xsize;y++){ tmp_bits [(x << 4) | y]= h->bits [j ]; tmp_codes[(x << 4) | y]= h->codes[j++]; } } /* XXX: fail test */ init_vlc(&huff_vlc[i], 7, 256, tmp_bits, 1, 1, tmp_codes, 2, 2, 1); } for(i=0;i<2;i++) { init_vlc(&huff_quad_vlc[i], i == 0 ? 7 : 4, 16, mpa_quad_bits[i], 1, 1, mpa_quad_codes[i], 1, 1, 1); } for(i=0;i<9;i++) { k = 0; for(j=0;j<22;j++) { band_index_long[i][j] = k; k += band_size_long[i][j]; } band_index_long[i][22] = k; } /* compute n ^ (4/3) and store it in mantissa/exp format */ table_4_3_exp= av_mallocz_static(TABLE_4_3_SIZE * sizeof(table_4_3_exp[0])); if(!table_4_3_exp) return -1; table_4_3_value= av_mallocz_static(TABLE_4_3_SIZE * sizeof(table_4_3_value[0])); if(!table_4_3_value) return -1; int_pow_init(); for(i=1;i<TABLE_4_3_SIZE;i++) { double f, fm; int e, m; f = pow((double)(i/4), 4.0 / 3.0) * pow(2, (i&3)*0.25); fm = frexp(f, &e); m = (uint32_t)(fm*(1LL<<31) + 0.5); e+= FRAC_BITS - 31 + 5; /* normalized to FRAC_BITS */ table_4_3_value[i] = m; // av_log(NULL, AV_LOG_DEBUG, "%d %d %f\n", i, m, pow((double)i, 4.0 / 3.0)); table_4_3_exp[i] = -e; } for(i=0; i<512*16; i++){ int exponent= (i>>4)-400; double f= pow(i&15, 4.0 / 3.0) * pow(2, exponent*0.25 + FRAC_BITS + 5); expval_table[exponent+400][i&15]= lrintf(f); if((i&15)==1) exp_table[exponent+400]= lrintf(f); } for(i=0;i<7;i++) { float f; int v; if (i != 6) { f = tan((double)i * M_PI / 12.0); v = FIXR(f / (1.0 + f)); } else { v = FIXR(1.0); } is_table[0][i] = v; is_table[1][6 - i] = v; } /* invalid values */ for(i=7;i<16;i++) is_table[0][i] = is_table[1][i] = 0.0; for(i=0;i<16;i++) { double f; int e, k; for(j=0;j<2;j++) { e = -(j + 1) * ((i + 1) >> 1); f = pow(2.0, e / 4.0); k = i & 1; is_table_lsf[j][k ^ 1][i] = FIXR(f); is_table_lsf[j][k][i] = FIXR(1.0); dprintf("is_table_lsf %d %d: %x %x\n", i, j, is_table_lsf[j][0][i], is_table_lsf[j][1][i]); } } for(i=0;i<8;i++) { float ci, cs, ca; ci = ci_table[i]; cs = 1.0 / sqrt(1.0 + ci * ci); ca = cs * ci; csa_table[i][0] = FIXHR(cs/4); csa_table[i][1] = FIXHR(ca/4); csa_table[i][2] = FIXHR(ca/4) + FIXHR(cs/4); csa_table[i][3] = FIXHR(ca/4) - FIXHR(cs/4); csa_table_float[i][0] = cs; csa_table_float[i][1] = ca; csa_table_float[i][2] = ca + cs; csa_table_float[i][3] = ca - cs; // printf("%d %d %d %d\n", FIX(cs), FIX(cs-1), FIX(ca), FIX(cs)-FIX(ca)); // av_log(NULL, AV_LOG_DEBUG,"%f %f %f %f\n", cs, ca, ca+cs, ca-cs); } /* compute mdct windows */ for(i=0;i<36;i++) { for(j=0; j<4; j++){ double d; if(j==2 && i%3 != 1) continue; d= sin(M_PI * (i + 0.5) / 36.0); if(j==1){ if (i>=30) d= 0; else if(i>=24) d= sin(M_PI * (i - 18 + 0.5) / 12.0); else if(i>=18) d= 1; }else if(j==3){ if (i< 6) d= 0; else if(i< 12) d= sin(M_PI * (i - 6 + 0.5) / 12.0); else if(i< 18) d= 1; } //merge last stage of imdct into the window coefficients d*= 0.5 / cos(M_PI*(2*i + 19)/72); if(j==2) mdct_win[j][i/3] = FIXHR((d / (1<<5))); else mdct_win[j][i ] = FIXHR((d / (1<<5))); // av_log(NULL, AV_LOG_DEBUG, "%2d %d %f\n", i,j,d / (1<<5)); } } /* NOTE: we do frequency inversion adter the MDCT by changing the sign of the right window coefs */ for(j=0;j<4;j++) { for(i=0;i<36;i+=2) { mdct_win[j + 4][i] = mdct_win[j][i]; mdct_win[j + 4][i + 1] = -mdct_win[j][i + 1]; } } #if defined(DEBUG) for(j=0;j<8;j++) { av_log(avctx, AV_LOG_DEBUG, "win%d=\n", j); for(i=0;i<36;i++) av_log(avctx, AV_LOG_DEBUG, "%f, ", (double)mdct_win[j][i] / FRAC_ONE); av_log(avctx, AV_LOG_DEBUG, "\n"); } #endif init = 1; } s->inbuf_index = 0; s->inbuf = &s->inbuf1[s->inbuf_index][BACKSTEP_SIZE]; s->inbuf_ptr = s->inbuf; #ifdef DEBUG s->frame_count = 0; #endif if (avctx->codec_id == CODEC_ID_MP3ADU) s->adu_mode = 1; return 0; }