/* * WMA compatible decoder * Copyright (c) 2002 The FFmpeg Project * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * WMA compatible decoder. * This decoder handles Microsoft Windows Media Audio data, versions 1 & 2. * WMA v1 is identified by audio format 0x160 in Microsoft media files * (ASF/AVI/WAV). WMA v2 is identified by audio format 0x161. * * To use this decoder, a calling application must supply the extra data * bytes provided with the WMA data. These are the extra, codec-specific * bytes at the end of a WAVEFORMATEX data structure. Transmit these bytes * to the decoder using the extradata[_size] fields in AVCodecContext. There * should be 4 extra bytes for v1 data and 6 extra bytes for v2 data. */ #include "avcodec.h" #include "wma.h" #undef NDEBUG #include <assert.h> #define EXPVLCBITS 8 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS) #define HGAINVLCBITS 9 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS) static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len); #ifdef TRACE static void dump_shorts(WMACodecContext *s, const char *name, const short *tab, int n) { int i; tprintf(s->avctx, "%s[%d]:\n", name, n); for(i=0;i<n;i++) { if ((i & 7) == 0) tprintf(s->avctx, "%4d: ", i); tprintf(s->avctx, " %5d.0", tab[i]); if ((i & 7) == 7) tprintf(s->avctx, "\n"); } } static void dump_floats(WMACodecContext *s, const char *name, int prec, const float *tab, int n) { int i; tprintf(s->avctx, "%s[%d]:\n", name, n); for(i=0;i<n;i++) { if ((i & 7) == 0) tprintf(s->avctx, "%4d: ", i); tprintf(s->avctx, " %8.*f", prec, tab[i]); if ((i & 7) == 7) tprintf(s->avctx, "\n"); } if ((i & 7) != 0) tprintf(s->avctx, "\n"); } #endif static int wma_decode_init(AVCodecContext * avctx) { WMACodecContext *s = avctx->priv_data; int i, flags2; uint8_t *extradata; s->avctx = avctx; /* extract flag infos */ flags2 = 0; extradata = avctx->extradata; if (avctx->codec->id == CODEC_ID_WMAV1 && avctx->extradata_size >= 4) { flags2 = AV_RL16(extradata+2); } else if (avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 6) { flags2 = AV_RL16(extradata+4); } // for(i=0; i<avctx->extradata_size; i++) // av_log(NULL, AV_LOG_ERROR, "%02X ", extradata[i]); s->use_exp_vlc = flags2 & 0x0001; s->use_bit_reservoir = flags2 & 0x0002; s->use_variable_block_len = flags2 & 0x0004; if(avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 8){ if(AV_RL16(extradata+4)==0xd && s->use_variable_block_len){ av_log(avctx, AV_LOG_WARNING, "Disabling use_variable_block_len, if this fails contact the ffmpeg developers and send us the file\n"); s->use_variable_block_len= 0; // this fixes issue1503 } } if(avctx->channels > MAX_CHANNELS){ av_log(avctx, AV_LOG_ERROR, "Invalid number of channels (%d)\n", avctx->channels); return -1; } if(ff_wma_init(avctx, flags2)<0) return -1; /* init MDCT */ for(i = 0; i < s->nb_block_sizes; i++) ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1, 1.0); if (s->use_noise_coding) { init_vlc(&s->hgain_vlc, HGAINVLCBITS, sizeof(ff_wma_hgain_huffbits), ff_wma_hgain_huffbits, 1, 1, ff_wma_hgain_huffcodes, 2, 2, 0); } if (s->use_exp_vlc) { init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_aac_scalefactor_bits), //FIXME move out of context ff_aac_scalefactor_bits, 1, 1, ff_aac_scalefactor_code, 4, 4, 0); } else { wma_lsp_to_curve_init(s, s->frame_len); } avctx->sample_fmt = AV_SAMPLE_FMT_S16; avcodec_get_frame_defaults(&s->frame); avctx->coded_frame = &s->frame; return 0; } /** * compute x^-0.25 with an exponent and mantissa table. We use linear * interpolation to reduce the mantissa table size at a small speed * expense (linear interpolation approximately doubles the number of * bits of precision). */ static inline float pow_m1_4(WMACodecContext *s, float x) { union { float f; unsigned int v; } u, t; unsigned int e, m; float a, b; u.f = x; e = u.v >> 23; m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1); /* build interpolation scale: 1 <= t < 2. */ t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23); a = s->lsp_pow_m_table1[m]; b = s->lsp_pow_m_table2[m]; return s->lsp_pow_e_table[e] * (a + b * t.f); } static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len) { float wdel, a, b; int i, e, m; wdel = M_PI / frame_len; for(i=0;i<frame_len;i++) s->lsp_cos_table[i] = 2.0f * cos(wdel * i); /* tables for x^-0.25 computation */ for(i=0;i<256;i++) { e = i - 126; s->lsp_pow_e_table[i] = pow(2.0, e * -0.25); } /* NOTE: these two tables are needed to avoid two operations in pow_m1_4 */ b = 1.0; for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) { m = (1 << LSP_POW_BITS) + i; a = (float)m * (0.5 / (1 << LSP_POW_BITS)); a = pow(a, -0.25); s->lsp_pow_m_table1[i] = 2 * a - b; s->lsp_pow_m_table2[i] = b - a; b = a; } } /** * NOTE: We use the same code as Vorbis here * @todo optimize it further with SSE/3Dnow */ static void wma_lsp_to_curve(WMACodecContext *s, float *out, float *val_max_ptr, int n, float *lsp) { int i, j; float p, q, w, v, val_max; val_max = 0; for(i=0;i<n;i++) { p = 0.5f; q = 0.5f; w = s->lsp_cos_table[i]; for(j=1;j<NB_LSP_COEFS;j+=2){ q *= w - lsp[j - 1]; p *= w - lsp[j]; } p *= p * (2.0f - w); q *= q * (2.0f + w); v = p + q; v = pow_m1_4(s, v); if (v > val_max) val_max = v; out[i] = v; } *val_max_ptr = val_max; } /** * decode exponents coded with LSP coefficients (same idea as Vorbis) */ static void decode_exp_lsp(WMACodecContext *s, int ch) { float lsp_coefs[NB_LSP_COEFS]; int val, i; for(i = 0; i < NB_LSP_COEFS; i++) { if (i == 0 || i >= 8) val = get_bits(&s->gb, 3); else val = get_bits(&s->gb, 4); lsp_coefs[i] = ff_wma_lsp_codebook[i][val]; } wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch], s->block_len, lsp_coefs); } /** pow(10, i / 16.0) for i in -60..95 */ static const float pow_tab[] = { 1.7782794100389e-04, 2.0535250264571e-04, 2.3713737056617e-04, 2.7384196342644e-04, 3.1622776601684e-04, 3.6517412725484e-04, 4.2169650342858e-04, 4.8696752516586e-04, 5.6234132519035e-04, 6.4938163157621e-04, 7.4989420933246e-04, 8.6596432336006e-04, 1.0000000000000e-03, 1.1547819846895e-03, 1.3335214321633e-03, 1.5399265260595e-03, 1.7782794100389e-03, 2.0535250264571e-03, 2.3713737056617e-03, 2.7384196342644e-03, 3.1622776601684e-03, 3.6517412725484e-03, 4.2169650342858e-03, 4.8696752516586e-03, 5.6234132519035e-03, 6.4938163157621e-03, 7.4989420933246e-03, 8.6596432336006e-03, 1.0000000000000e-02, 1.1547819846895e-02, 1.3335214321633e-02, 1.5399265260595e-02, 1.7782794100389e-02, 2.0535250264571e-02, 2.3713737056617e-02, 2.7384196342644e-02, 3.1622776601684e-02, 3.6517412725484e-02, 4.2169650342858e-02, 4.8696752516586e-02, 5.6234132519035e-02, 6.4938163157621e-02, 7.4989420933246e-02, 8.6596432336007e-02, 1.0000000000000e-01, 1.1547819846895e-01, 1.3335214321633e-01, 1.5399265260595e-01, 1.7782794100389e-01, 2.0535250264571e-01, 2.3713737056617e-01, 2.7384196342644e-01, 3.1622776601684e-01, 3.6517412725484e-01, 4.2169650342858e-01, 4.8696752516586e-01, 5.6234132519035e-01, 6.4938163157621e-01, 7.4989420933246e-01, 8.6596432336007e-01, 1.0000000000000e+00, 1.1547819846895e+00, 1.3335214321633e+00, 1.5399265260595e+00, 1.7782794100389e+00, 2.0535250264571e+00, 2.3713737056617e+00, 2.7384196342644e+00, 3.1622776601684e+00, 3.6517412725484e+00, 4.2169650342858e+00, 4.8696752516586e+00, 5.6234132519035e+00, 6.4938163157621e+00, 7.4989420933246e+00, 8.6596432336007e+00, 1.0000000000000e+01, 1.1547819846895e+01, 1.3335214321633e+01, 1.5399265260595e+01, 1.7782794100389e+01, 2.0535250264571e+01, 2.3713737056617e+01, 2.7384196342644e+01, 3.1622776601684e+01, 3.6517412725484e+01, 4.2169650342858e+01, 4.8696752516586e+01, 5.6234132519035e+01, 6.4938163157621e+01, 7.4989420933246e+01, 8.6596432336007e+01, 1.0000000000000e+02, 1.1547819846895e+02, 1.3335214321633e+02, 1.5399265260595e+02, 1.7782794100389e+02, 2.0535250264571e+02, 2.3713737056617e+02, 2.7384196342644e+02, 3.1622776601684e+02, 3.6517412725484e+02, 4.2169650342858e+02, 4.8696752516586e+02, 5.6234132519035e+02, 6.4938163157621e+02, 7.4989420933246e+02, 8.6596432336007e+02, 1.0000000000000e+03, 1.1547819846895e+03, 1.3335214321633e+03, 1.5399265260595e+03, 1.7782794100389e+03, 2.0535250264571e+03, 2.3713737056617e+03, 2.7384196342644e+03, 3.1622776601684e+03, 3.6517412725484e+03, 4.2169650342858e+03, 4.8696752516586e+03, 5.6234132519035e+03, 6.4938163157621e+03, 7.4989420933246e+03, 8.6596432336007e+03, 1.0000000000000e+04, 1.1547819846895e+04, 1.3335214321633e+04, 1.5399265260595e+04, 1.7782794100389e+04, 2.0535250264571e+04, 2.3713737056617e+04, 2.7384196342644e+04, 3.1622776601684e+04, 3.6517412725484e+04, 4.2169650342858e+04, 4.8696752516586e+04, 5.6234132519035e+04, 6.4938163157621e+04, 7.4989420933246e+04, 8.6596432336007e+04, 1.0000000000000e+05, 1.1547819846895e+05, 1.3335214321633e+05, 1.5399265260595e+05, 1.7782794100389e+05, 2.0535250264571e+05, 2.3713737056617e+05, 2.7384196342644e+05, 3.1622776601684e+05, 3.6517412725484e+05, 4.2169650342858e+05, 4.8696752516586e+05, 5.6234132519035e+05, 6.4938163157621e+05, 7.4989420933246e+05, 8.6596432336007e+05, }; /** * decode exponents coded with VLC codes */ static int decode_exp_vlc(WMACodecContext *s, int ch) { int last_exp, n, code; const uint16_t *ptr; float v, max_scale; uint32_t *q, *q_end, iv; const float *ptab = pow_tab + 60; const uint32_t *iptab = (const uint32_t*)ptab; ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits]; q = (uint32_t *)s->exponents[ch]; q_end = q + s->block_len; max_scale = 0; if (s->version == 1) { last_exp = get_bits(&s->gb, 5) + 10; v = ptab[last_exp]; iv = iptab[last_exp]; max_scale = v; n = *ptr++; switch (n & 3) do { case 0: *q++ = iv; case 3: *q++ = iv; case 2: *q++ = iv; case 1: *q++ = iv; } while ((n -= 4) > 0); }else last_exp = 36; while (q < q_end) { code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX); if (code < 0){ av_log(s->avctx, AV_LOG_ERROR, "Exponent vlc invalid\n"); return -1; } /* NOTE: this offset is the same as MPEG4 AAC ! */ last_exp += code - 60; if ((unsigned)last_exp + 60 > FF_ARRAY_ELEMS(pow_tab)) { av_log(s->avctx, AV_LOG_ERROR, "Exponent out of range: %d\n", last_exp); return -1; } v = ptab[last_exp]; iv = iptab[last_exp]; if (v > max_scale) max_scale = v; n = *ptr++; switch (n & 3) do { case 0: *q++ = iv; case 3: *q++ = iv; case 2: *q++ = iv; case 1: *q++ = iv; } while ((n -= 4) > 0); } s->max_exponent[ch] = max_scale; return 0; } /** * Apply MDCT window and add into output. * * We ensure that when the windows overlap their squared sum * is always 1 (MDCT reconstruction rule). */ static void wma_window(WMACodecContext *s, float *out) { float *in = s->output; int block_len, bsize, n; /* left part */ if (s->block_len_bits <= s->prev_block_len_bits) { block_len = s->block_len; bsize = s->frame_len_bits - s->block_len_bits; s->dsp.vector_fmul_add(out, in, s->windows[bsize], out, block_len); } else { block_len = 1 << s->prev_block_len_bits; n = (s->block_len - block_len) / 2; bsize = s->frame_len_bits - s->prev_block_len_bits; s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize], out+n, block_len); memcpy(out+n+block_len, in+n+block_len, n*sizeof(float)); } out += s->block_len; in += s->block_len; /* right part */ if (s->block_len_bits <= s->next_block_len_bits) { block_len = s->block_len; bsize = s->frame_len_bits - s->block_len_bits; s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len); } else { block_len = 1 << s->next_block_len_bits; n = (s->block_len - block_len) / 2; bsize = s->frame_len_bits - s->next_block_len_bits; memcpy(out, in, n*sizeof(float)); s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len); memset(out+n+block_len, 0, n*sizeof(float)); } } /** * @return 0 if OK. 1 if last block of frame. return -1 if * unrecorrable error. */ static int wma_decode_block(WMACodecContext *s) { int n, v, a, ch, bsize; int coef_nb_bits, total_gain; int nb_coefs[MAX_CHANNELS]; float mdct_norm; FFTContext *mdct; #ifdef TRACE tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num); #endif /* compute current block length */ if (s->use_variable_block_len) { n = av_log2(s->nb_block_sizes - 1) + 1; if (s->reset_block_lengths) { s->reset_block_lengths = 0; v = get_bits(&s->gb, n); if (v >= s->nb_block_sizes){ av_log(s->avctx, AV_LOG_ERROR, "prev_block_len_bits %d out of range\n", s->frame_len_bits - v); return -1; } s->prev_block_len_bits = s->frame_len_bits - v; v = get_bits(&s->gb, n); if (v >= s->nb_block_sizes){ av_log(s->avctx, AV_LOG_ERROR, "block_len_bits %d out of range\n", s->frame_len_bits - v); return -1; } s->block_len_bits = s->frame_len_bits - v; } else { /* update block lengths */ s->prev_block_len_bits = s->block_len_bits; s->block_len_bits = s->next_block_len_bits; } v = get_bits(&s->gb, n); if (v >= s->nb_block_sizes){ av_log(s->avctx, AV_LOG_ERROR, "next_block_len_bits %d out of range\n", s->frame_len_bits - v); return -1; } s->next_block_len_bits = s->frame_len_bits - v; } else { /* fixed block len */ s->next_block_len_bits = s->frame_len_bits; s->prev_block_len_bits = s->frame_len_bits; s->block_len_bits = s->frame_len_bits; } if (s->frame_len_bits - s->block_len_bits >= s->nb_block_sizes){ av_log(s->avctx, AV_LOG_ERROR, "block_len_bits not initialized to a valid value\n"); return -1; } /* now check if the block length is coherent with the frame length */ s->block_len = 1 << s->block_len_bits; if ((s->block_pos + s->block_len) > s->frame_len){ av_log(s->avctx, AV_LOG_ERROR, "frame_len overflow\n"); return -1; } if (s->nb_channels == 2) { s->ms_stereo = get_bits1(&s->gb); } v = 0; for(ch = 0; ch < s->nb_channels; ch++) { a = get_bits1(&s->gb); s->channel_coded[ch] = a; v |= a; } bsize = s->frame_len_bits - s->block_len_bits; /* if no channel coded, no need to go further */ /* XXX: fix potential framing problems */ if (!v) goto next; /* read total gain and extract corresponding number of bits for coef escape coding */ total_gain = 1; for(;;) { a = get_bits(&s->gb, 7); total_gain += a; if (a != 127) break; } coef_nb_bits= ff_wma_total_gain_to_bits(total_gain); /* compute number of coefficients */ n = s->coefs_end[bsize] - s->coefs_start; for(ch = 0; ch < s->nb_channels; ch++) nb_coefs[ch] = n; /* complex coding */ if (s->use_noise_coding) { for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { int i, n, a; n = s->exponent_high_sizes[bsize]; for(i=0;i<n;i++) { a = get_bits1(&s->gb); s->high_band_coded[ch][i] = a; /* if noise coding, the coefficients are not transmitted */ if (a) nb_coefs[ch] -= s->exponent_high_bands[bsize][i]; } } } for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { int i, n, val, code; n = s->exponent_high_sizes[bsize]; val = (int)0x80000000; for(i=0;i<n;i++) { if (s->high_band_coded[ch][i]) { if (val == (int)0x80000000) { val = get_bits(&s->gb, 7) - 19; } else { code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX); if (code < 0){ av_log(s->avctx, AV_LOG_ERROR, "hgain vlc invalid\n"); return -1; } val += code - 18; } s->high_band_values[ch][i] = val; } } } } } /* exponents can be reused in short blocks. */ if ((s->block_len_bits == s->frame_len_bits) || get_bits1(&s->gb)) { for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { if (s->use_exp_vlc) { if (decode_exp_vlc(s, ch) < 0) return -1; } else { decode_exp_lsp(s, ch); } s->exponents_bsize[ch] = bsize; } } } /* parse spectral coefficients : just RLE encoding */ for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { int tindex; WMACoef* ptr = &s->coefs1[ch][0]; /* special VLC tables are used for ms stereo because there is potentially less energy there */ tindex = (ch == 1 && s->ms_stereo); memset(ptr, 0, s->block_len * sizeof(WMACoef)); ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex], s->level_table[tindex], s->run_table[tindex], 0, ptr, 0, nb_coefs[ch], s->block_len, s->frame_len_bits, coef_nb_bits); } if (s->version == 1 && s->nb_channels >= 2) { align_get_bits(&s->gb); } } /* normalize */ { int n4 = s->block_len / 2; mdct_norm = 1.0 / (float)n4; if (s->version == 1) { mdct_norm *= sqrt(n4); } } /* finally compute the MDCT coefficients */ for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { WMACoef *coefs1; float *coefs, *exponents, mult, mult1, noise; int i, j, n, n1, last_high_band, esize; float exp_power[HIGH_BAND_MAX_SIZE]; coefs1 = s->coefs1[ch]; exponents = s->exponents[ch]; esize = s->exponents_bsize[ch]; mult = pow(10, total_gain * 0.05) / s->max_exponent[ch]; mult *= mdct_norm; coefs = s->coefs[ch]; if (s->use_noise_coding) { mult1 = mult; /* very low freqs : noise */ for(i = 0;i < s->coefs_start; i++) { *coefs++ = s->noise_table[s->noise_index] * exponents[i<<bsize>>esize] * mult1; s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); } n1 = s->exponent_high_sizes[bsize]; /* compute power of high bands */ exponents = s->exponents[ch] + (s->high_band_start[bsize]<<bsize>>esize); last_high_band = 0; /* avoid warning */ for(j=0;j<n1;j++) { n = s->exponent_high_bands[s->frame_len_bits - s->block_len_bits][j]; if (s->high_band_coded[ch][j]) { float e2, v; e2 = 0; for(i = 0;i < n; i++) { v = exponents[i<<bsize>>esize]; e2 += v * v; } exp_power[j] = e2 / n; last_high_band = j; tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n); } exponents += n<<bsize>>esize; } /* main freqs and high freqs */ exponents = s->exponents[ch] + (s->coefs_start<<bsize>>esize); for(j=-1;j<n1;j++) { if (j < 0) { n = s->high_band_start[bsize] - s->coefs_start; } else { n = s->exponent_high_bands[s->frame_len_bits - s->block_len_bits][j]; } if (j >= 0 && s->high_band_coded[ch][j]) { /* use noise with specified power */ mult1 = sqrt(exp_power[j] / exp_power[last_high_band]); /* XXX: use a table */ mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05); mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult); mult1 *= mdct_norm; for(i = 0;i < n; i++) { noise = s->noise_table[s->noise_index]; s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); *coefs++ = noise * exponents[i<<bsize>>esize] * mult1; } exponents += n<<bsize>>esize; } else { /* coded values + small noise */ for(i = 0;i < n; i++) { noise = s->noise_table[s->noise_index]; s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); *coefs++ = ((*coefs1++) + noise) * exponents[i<<bsize>>esize] * mult; } exponents += n<<bsize>>esize; } } /* very high freqs : noise */ n = s->block_len - s->coefs_end[bsize]; mult1 = mult * exponents[((-1<<bsize))>>esize]; for(i = 0; i < n; i++) { *coefs++ = s->noise_table[s->noise_index] * mult1; s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1); } } else { /* XXX: optimize more */ for(i = 0;i < s->coefs_start; i++) *coefs++ = 0.0; n = nb_coefs[ch]; for(i = 0;i < n; i++) { *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult; } n = s->block_len - s->coefs_end[bsize]; for(i = 0;i < n; i++) *coefs++ = 0.0; } } } #ifdef TRACE for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len); dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len); } } #endif if (s->ms_stereo && s->channel_coded[1]) { /* nominal case for ms stereo: we do it before mdct */ /* no need to optimize this case because it should almost never happen */ if (!s->channel_coded[0]) { tprintf(s->avctx, "rare ms-stereo case happened\n"); memset(s->coefs[0], 0, sizeof(float) * s->block_len); s->channel_coded[0] = 1; } s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len); } next: mdct = &s->mdct_ctx[bsize]; for(ch = 0; ch < s->nb_channels; ch++) { int n4, index; n4 = s->block_len / 2; if(s->channel_coded[ch]){ mdct->imdct_calc(mdct, s->output, s->coefs[ch]); }else if(!(s->ms_stereo && ch==1)) memset(s->output, 0, sizeof(s->output)); /* multiply by the window and add in the frame */ index = (s->frame_len / 2) + s->block_pos - n4; wma_window(s, &s->frame_out[ch][index]); } /* update block number */ s->block_num++; s->block_pos += s->block_len; if (s->block_pos >= s->frame_len) return 1; else return 0; } /* decode a frame of frame_len samples */ static int wma_decode_frame(WMACodecContext *s, int16_t *samples) { int ret, n, ch, incr; const float *output[MAX_CHANNELS]; #ifdef TRACE tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len); #endif /* read each block */ s->block_num = 0; s->block_pos = 0; for(;;) { ret = wma_decode_block(s); if (ret < 0) return -1; if (ret) break; } /* convert frame to integer */ n = s->frame_len; incr = s->nb_channels; for (ch = 0; ch < MAX_CHANNELS; ch++) output[ch] = s->frame_out[ch]; s->fmt_conv.float_to_int16_interleave(samples, output, n, incr); for (ch = 0; ch < incr; ch++) { /* prepare for next block */ memmove(&s->frame_out[ch][0], &s->frame_out[ch][n], n * sizeof(float)); } #ifdef TRACE dump_shorts(s, "samples", samples, n * s->nb_channels); #endif return 0; } static int wma_decode_superframe(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; WMACodecContext *s = avctx->priv_data; int nb_frames, bit_offset, i, pos, len, ret; uint8_t *q; int16_t *samples; tprintf(avctx, "***decode_superframe:\n"); if(buf_size==0){ s->last_superframe_len = 0; return 0; } if (buf_size < s->block_align) return AVERROR(EINVAL); if(s->block_align) buf_size = s->block_align; init_get_bits(&s->gb, buf, buf_size*8); if (s->use_bit_reservoir) { /* read super frame header */ skip_bits(&s->gb, 4); /* super frame index */ nb_frames = get_bits(&s->gb, 4) - (s->last_superframe_len <= 0); } else { nb_frames = 1; } /* get output buffer */ s->frame.nb_samples = nb_frames * s->frame_len; if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return ret; } samples = (int16_t *)s->frame.data[0]; if (s->use_bit_reservoir) { bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3); if (s->last_superframe_len > 0) { // printf("skip=%d\n", s->last_bitoffset); /* add bit_offset bits to last frame */ if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) > MAX_CODED_SUPERFRAME_SIZE) goto fail; q = s->last_superframe + s->last_superframe_len; len = bit_offset; while (len > 7) { *q++ = (get_bits)(&s->gb, 8); len -= 8; } if (len > 0) { *q++ = (get_bits)(&s->gb, len) << (8 - len); } /* XXX: bit_offset bits into last frame */ init_get_bits(&s->gb, s->last_superframe, MAX_CODED_SUPERFRAME_SIZE*8); /* skip unused bits */ if (s->last_bitoffset > 0) skip_bits(&s->gb, s->last_bitoffset); /* this frame is stored in the last superframe and in the current one */ if (wma_decode_frame(s, samples) < 0) goto fail; samples += s->nb_channels * s->frame_len; nb_frames--; } /* read each frame starting from bit_offset */ pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3; init_get_bits(&s->gb, buf + (pos >> 3), (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3))*8); len = pos & 7; if (len > 0) skip_bits(&s->gb, len); s->reset_block_lengths = 1; for(i=0;i<nb_frames;i++) { if (wma_decode_frame(s, samples) < 0) goto fail; samples += s->nb_channels * s->frame_len; } /* we copy the end of the frame in the last frame buffer */ pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7); s->last_bitoffset = pos & 7; pos >>= 3; len = buf_size - pos; if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) { av_log(s->avctx, AV_LOG_ERROR, "len %d invalid\n", len); goto fail; } s->last_superframe_len = len; memcpy(s->last_superframe, buf + pos, len); } else { /* single frame decode */ if (wma_decode_frame(s, samples) < 0) goto fail; samples += s->nb_channels * s->frame_len; } //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d outbytes:%d eaten:%d\n", s->frame_len_bits, s->block_len_bits, s->frame_len, s->block_len, (int8_t *)samples - (int8_t *)data, s->block_align); *got_frame_ptr = 1; *(AVFrame *)data = s->frame; return buf_size; fail: /* when error, we reset the bit reservoir */ s->last_superframe_len = 0; return -1; } static av_cold void flush(AVCodecContext *avctx) { WMACodecContext *s = avctx->priv_data; s->last_bitoffset= s->last_superframe_len= 0; } AVCodec ff_wmav1_decoder = { .name = "wmav1", .type = AVMEDIA_TYPE_AUDIO, .id = CODEC_ID_WMAV1, .priv_data_size = sizeof(WMACodecContext), .init = wma_decode_init, .close = ff_wma_end, .decode = wma_decode_superframe, .flush = flush, .capabilities = CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"), }; AVCodec ff_wmav2_decoder = { .name = "wmav2", .type = AVMEDIA_TYPE_AUDIO, .id = CODEC_ID_WMAV2, .priv_data_size = sizeof(WMACodecContext), .init = wma_decode_init, .close = ff_wma_end, .decode = wma_decode_superframe, .flush = flush, .capabilities = CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"), };