yading@10: /*
yading@10:  * WMA compatible codec
yading@10:  * Copyright (c) 2002-2007 The FFmpeg Project
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "sinewin.h"
yading@10: #include "wma.h"
yading@10: #include "wma_common.h"
yading@10: #include "wmadata.h"
yading@10: 
yading@10: #undef NDEBUG
yading@10: #include <assert.h>
yading@10: 
yading@10: /* XXX: use same run/length optimization as mpeg decoders */
yading@10: //FIXME maybe split decode / encode or pass flag
yading@10: static void init_coef_vlc(VLC *vlc, uint16_t **prun_table,
yading@10:                           float **plevel_table, uint16_t **pint_table,
yading@10:                           const CoefVLCTable *vlc_table)
yading@10: {
yading@10:     int n = vlc_table->n;
yading@10:     const uint8_t  *table_bits   = vlc_table->huffbits;
yading@10:     const uint32_t *table_codes  = vlc_table->huffcodes;
yading@10:     const uint16_t *levels_table = vlc_table->levels;
yading@10:     uint16_t *run_table, *level_table, *int_table;
yading@10:     float *flevel_table;
yading@10:     int i, l, j, k, level;
yading@10: 
yading@10:     init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
yading@10: 
yading@10:     run_table   = av_malloc(n * sizeof(uint16_t));
yading@10:     level_table = av_malloc(n * sizeof(uint16_t));
yading@10:     flevel_table= av_malloc(n * sizeof(*flevel_table));
yading@10:     int_table   = av_malloc(n * sizeof(uint16_t));
yading@10:     i = 2;
yading@10:     level = 1;
yading@10:     k = 0;
yading@10:     while (i < n) {
yading@10:         int_table[k] = i;
yading@10:         l = levels_table[k++];
yading@10:         for (j = 0; j < l; j++) {
yading@10:             run_table[i]   = j;
yading@10:             level_table[i] = level;
yading@10:             flevel_table[i]= level;
yading@10:             i++;
yading@10:         }
yading@10:         level++;
yading@10:     }
yading@10:     *prun_table   = run_table;
yading@10:     *plevel_table = flevel_table;
yading@10:     *pint_table   = int_table;
yading@10:     av_free(level_table);
yading@10: }
yading@10: 
yading@10: int ff_wma_init(AVCodecContext *avctx, int flags2)
yading@10: {
yading@10:     WMACodecContext *s = avctx->priv_data;
yading@10:     int i;
yading@10:     float bps1, high_freq;
yading@10:     volatile float bps;
yading@10:     int sample_rate1;
yading@10:     int coef_vlc_table;
yading@10: 
yading@10:     if (   avctx->sample_rate <= 0 || avctx->sample_rate > 50000
yading@10:         || avctx->channels    <= 0 || avctx->channels    > 2
yading@10:         || avctx->bit_rate    <= 0)
yading@10:         return -1;
yading@10: 
yading@10:     ff_fmt_convert_init(&s->fmt_conv, avctx);
yading@10:     avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
yading@10: 
yading@10:     if (avctx->codec->id == AV_CODEC_ID_WMAV1) {
yading@10:         s->version = 1;
yading@10:     } else {
yading@10:         s->version = 2;
yading@10:     }
yading@10: 
yading@10:     /* compute MDCT block size */
yading@10:     s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
yading@10:                                                   s->version, 0);
yading@10:     s->next_block_len_bits = s->frame_len_bits;
yading@10:     s->prev_block_len_bits = s->frame_len_bits;
yading@10:     s->block_len_bits      = s->frame_len_bits;
yading@10: 
yading@10:     s->frame_len = 1 << s->frame_len_bits;
yading@10:     if (s->use_variable_block_len) {
yading@10:         int nb_max, nb;
yading@10:         nb = ((flags2 >> 3) & 3) + 1;
yading@10:         if ((avctx->bit_rate / avctx->channels) >= 32000)
yading@10:             nb += 2;
yading@10:         nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
yading@10:         if (nb > nb_max)
yading@10:             nb = nb_max;
yading@10:         s->nb_block_sizes = nb + 1;
yading@10:     } else {
yading@10:         s->nb_block_sizes = 1;
yading@10:     }
yading@10: 
yading@10:     /* init rate dependent parameters */
yading@10:     s->use_noise_coding = 1;
yading@10:     high_freq = avctx->sample_rate * 0.5;
yading@10: 
yading@10:     /* if version 2, then the rates are normalized */
yading@10:     sample_rate1 = avctx->sample_rate;
yading@10:     if (s->version == 2) {
yading@10:         if (sample_rate1 >= 44100) {
yading@10:             sample_rate1 = 44100;
yading@10:         } else if (sample_rate1 >= 22050) {
yading@10:             sample_rate1 = 22050;
yading@10:         } else if (sample_rate1 >= 16000) {
yading@10:             sample_rate1 = 16000;
yading@10:         } else if (sample_rate1 >= 11025) {
yading@10:             sample_rate1 = 11025;
yading@10:         } else if (sample_rate1 >= 8000) {
yading@10:             sample_rate1 = 8000;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     bps = (float)avctx->bit_rate / (float)(avctx->channels * avctx->sample_rate);
yading@10:     s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
yading@10:     if (s->byte_offset_bits + 3 > MIN_CACHE_BITS) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "byte_offset_bits %d is too large\n", s->byte_offset_bits);
yading@10:         return AVERROR_PATCHWELCOME;
yading@10:     }
yading@10: 
yading@10:     /* compute high frequency value and choose if noise coding should
yading@10:        be activated */
yading@10:     bps1 = bps;
yading@10:     if (avctx->channels == 2)
yading@10:         bps1 = bps * 1.6;
yading@10:     if (sample_rate1 == 44100) {
yading@10:         if (bps1 >= 0.61) {
yading@10:             s->use_noise_coding = 0;
yading@10:         } else {
yading@10:             high_freq = high_freq * 0.4;
yading@10:         }
yading@10:     } else if (sample_rate1 == 22050) {
yading@10:         if (bps1 >= 1.16) {
yading@10:             s->use_noise_coding = 0;
yading@10:         } else if (bps1 >= 0.72) {
yading@10:             high_freq = high_freq * 0.7;
yading@10:         } else {
yading@10:             high_freq = high_freq * 0.6;
yading@10:         }
yading@10:     } else if (sample_rate1 == 16000) {
yading@10:         if (bps > 0.5) {
yading@10:             high_freq = high_freq * 0.5;
yading@10:         } else {
yading@10:             high_freq = high_freq * 0.3;
yading@10:         }
yading@10:     } else if (sample_rate1 == 11025) {
yading@10:         high_freq = high_freq * 0.7;
yading@10:     } else if (sample_rate1 == 8000) {
yading@10:         if (bps <= 0.625) {
yading@10:             high_freq = high_freq * 0.5;
yading@10:         } else if (bps > 0.75) {
yading@10:             s->use_noise_coding = 0;
yading@10:         } else {
yading@10:             high_freq = high_freq * 0.65;
yading@10:         }
yading@10:     } else {
yading@10:         if (bps >= 0.8) {
yading@10:             high_freq = high_freq * 0.75;
yading@10:         } else if (bps >= 0.6) {
yading@10:             high_freq = high_freq * 0.6;
yading@10:         } else {
yading@10:             high_freq = high_freq * 0.5;
yading@10:         }
yading@10:     }
yading@10:     av_dlog(s->avctx, "flags2=0x%x\n", flags2);
yading@10:     av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
yading@10:             s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate,
yading@10:             avctx->block_align);
yading@10:     av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
yading@10:             bps, bps1, high_freq, s->byte_offset_bits);
yading@10:     av_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
yading@10:             s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
yading@10: 
yading@10:     /* compute the scale factor band sizes for each MDCT block size */
yading@10:     {
yading@10:         int a, b, pos, lpos, k, block_len, i, j, n;
yading@10:         const uint8_t *table;
yading@10: 
yading@10:         if (s->version == 1) {
yading@10:             s->coefs_start = 3;
yading@10:         } else {
yading@10:             s->coefs_start = 0;
yading@10:         }
yading@10:         for (k = 0; k < s->nb_block_sizes; k++) {
yading@10:             block_len = s->frame_len >> k;
yading@10: 
yading@10:             if (s->version == 1) {
yading@10:                 lpos = 0;
yading@10:                 for (i = 0; i < 25; i++) {
yading@10:                     a = ff_wma_critical_freqs[i];
yading@10:                     b = avctx->sample_rate;
yading@10:                     pos = ((block_len * 2 * a) + (b >> 1)) / b;
yading@10:                     if (pos > block_len)
yading@10:                         pos = block_len;
yading@10:                     s->exponent_bands[0][i] = pos - lpos;
yading@10:                     if (pos >= block_len) {
yading@10:                         i++;
yading@10:                         break;
yading@10:                     }
yading@10:                     lpos = pos;
yading@10:                 }
yading@10:                 s->exponent_sizes[0] = i;
yading@10:             } else {
yading@10:                 /* hardcoded tables */
yading@10:                 table = NULL;
yading@10:                 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
yading@10:                 if (a < 3) {
yading@10:                     if (avctx->sample_rate >= 44100) {
yading@10:                         table = exponent_band_44100[a];
yading@10:                     } else if (avctx->sample_rate >= 32000) {
yading@10:                         table = exponent_band_32000[a];
yading@10:                     } else if (avctx->sample_rate >= 22050) {
yading@10:                         table = exponent_band_22050[a];
yading@10:                     }
yading@10:                 }
yading@10:                 if (table) {
yading@10:                     n = *table++;
yading@10:                     for (i = 0; i < n; i++)
yading@10:                         s->exponent_bands[k][i] = table[i];
yading@10:                     s->exponent_sizes[k] = n;
yading@10:                 } else {
yading@10:                     j = 0;
yading@10:                     lpos = 0;
yading@10:                     for (i = 0; i < 25; i++) {
yading@10:                         a = ff_wma_critical_freqs[i];
yading@10:                         b = avctx->sample_rate;
yading@10:                         pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
yading@10:                         pos <<= 2;
yading@10:                         if (pos > block_len)
yading@10:                             pos = block_len;
yading@10:                         if (pos > lpos)
yading@10:                             s->exponent_bands[k][j++] = pos - lpos;
yading@10:                         if (pos >= block_len)
yading@10:                             break;
yading@10:                         lpos = pos;
yading@10:                     }
yading@10:                     s->exponent_sizes[k] = j;
yading@10:                 }
yading@10:             }
yading@10: 
yading@10:             /* max number of coefs */
yading@10:             s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
yading@10:             /* high freq computation */
yading@10:             s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
yading@10:                                           avctx->sample_rate + 0.5);
yading@10:             n = s->exponent_sizes[k];
yading@10:             j = 0;
yading@10:             pos = 0;
yading@10:             for (i = 0; i < n; i++) {
yading@10:                 int start, end;
yading@10:                 start = pos;
yading@10:                 pos += s->exponent_bands[k][i];
yading@10:                 end = pos;
yading@10:                 if (start < s->high_band_start[k])
yading@10:                     start = s->high_band_start[k];
yading@10:                 if (end > s->coefs_end[k])
yading@10:                     end = s->coefs_end[k];
yading@10:                 if (end > start)
yading@10:                     s->exponent_high_bands[k][j++] = end - start;
yading@10:             }
yading@10:             s->exponent_high_sizes[k] = j;
yading@10: #if 0
yading@10:             tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
yading@10:                     s->frame_len >> k,
yading@10:                     s->coefs_end[k],
yading@10:                     s->high_band_start[k],
yading@10:                     s->exponent_high_sizes[k]);
yading@10:             for (j = 0; j < s->exponent_high_sizes[k]; j++)
yading@10:                 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
yading@10:             tprintf(s->avctx, "\n");
yading@10: #endif
yading@10:         }
yading@10:     }
yading@10: 
yading@10: #ifdef TRACE
yading@10:     {
yading@10:         int i, j;
yading@10:         for (i = 0; i < s->nb_block_sizes; i++) {
yading@10:             tprintf(s->avctx, "%5d: n=%2d:",
yading@10:                     s->frame_len >> i,
yading@10:                     s->exponent_sizes[i]);
yading@10:             for (j = 0; j < s->exponent_sizes[i]; j++)
yading@10:                 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
yading@10:             tprintf(s->avctx, "\n");
yading@10:         }
yading@10:     }
yading@10: #endif
yading@10: 
yading@10:     /* init MDCT windows : simple sinus window */
yading@10:     for (i = 0; i < s->nb_block_sizes; i++) {
yading@10:         ff_init_ff_sine_windows(s->frame_len_bits - i);
yading@10:         s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
yading@10:     }
yading@10: 
yading@10:     s->reset_block_lengths = 1;
yading@10: 
yading@10:     if (s->use_noise_coding) {
yading@10: 
yading@10:         /* init the noise generator */
yading@10:         if (s->use_exp_vlc) {
yading@10:             s->noise_mult = 0.02;
yading@10:         } else {
yading@10:             s->noise_mult = 0.04;
yading@10:         }
yading@10: 
yading@10: #ifdef TRACE
yading@10:         for (i = 0; i < NOISE_TAB_SIZE; i++)
yading@10:             s->noise_table[i] = 1.0 * s->noise_mult;
yading@10: #else
yading@10:         {
yading@10:             unsigned int seed;
yading@10:             float norm;
yading@10:             seed = 1;
yading@10:             norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
yading@10:             for (i = 0; i < NOISE_TAB_SIZE; i++) {
yading@10:                 seed = seed * 314159 + 1;
yading@10:                 s->noise_table[i] = (float)((int)seed) * norm;
yading@10:             }
yading@10:         }
yading@10: #endif
yading@10:     }
yading@10: 
yading@10:     /* choose the VLC tables for the coefficients */
yading@10:     coef_vlc_table = 2;
yading@10:     if (avctx->sample_rate >= 32000) {
yading@10:         if (bps1 < 0.72) {
yading@10:             coef_vlc_table = 0;
yading@10:         } else if (bps1 < 1.16) {
yading@10:             coef_vlc_table = 1;
yading@10:         }
yading@10:     }
yading@10:     s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2    ];
yading@10:     s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
yading@10:     init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
yading@10:                   s->coef_vlcs[0]);
yading@10:     init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
yading@10:                   s->coef_vlcs[1]);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: int ff_wma_total_gain_to_bits(int total_gain)
yading@10: {
yading@10:          if (total_gain < 15) return 13;
yading@10:     else if (total_gain < 32) return 12;
yading@10:     else if (total_gain < 40) return 11;
yading@10:     else if (total_gain < 45) return 10;
yading@10:     else                      return  9;
yading@10: }
yading@10: 
yading@10: int ff_wma_end(AVCodecContext *avctx)
yading@10: {
yading@10:     WMACodecContext *s = avctx->priv_data;
yading@10:     int i;
yading@10: 
yading@10:     for (i = 0; i < s->nb_block_sizes; i++)
yading@10:         ff_mdct_end(&s->mdct_ctx[i]);
yading@10: 
yading@10:     if (s->use_exp_vlc) {
yading@10:         ff_free_vlc(&s->exp_vlc);
yading@10:     }
yading@10:     if (s->use_noise_coding) {
yading@10:         ff_free_vlc(&s->hgain_vlc);
yading@10:     }
yading@10:     for (i = 0; i < 2; i++) {
yading@10:         ff_free_vlc(&s->coef_vlc[i]);
yading@10:         av_free(s->run_table[i]);
yading@10:         av_free(s->level_table[i]);
yading@10:         av_free(s->int_table[i]);
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decode an uncompressed coefficient.
yading@10:  * @param gb GetBitContext
yading@10:  * @return the decoded coefficient
yading@10:  */
yading@10: unsigned int ff_wma_get_large_val(GetBitContext* gb)
yading@10: {
yading@10:     /** consumes up to 34 bits */
yading@10:     int n_bits = 8;
yading@10:     /** decode length */
yading@10:     if (get_bits1(gb)) {
yading@10:         n_bits += 8;
yading@10:         if (get_bits1(gb)) {
yading@10:             n_bits += 8;
yading@10:             if (get_bits1(gb)) {
yading@10:                 n_bits += 7;
yading@10:             }
yading@10:         }
yading@10:     }
yading@10:     return get_bits_long(gb, n_bits);
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decode run level compressed coefficients.
yading@10:  * @param avctx codec context
yading@10:  * @param gb bitstream reader context
yading@10:  * @param vlc vlc table for get_vlc2
yading@10:  * @param level_table level codes
yading@10:  * @param run_table run codes
yading@10:  * @param version 0 for wma1,2 1 for wmapro
yading@10:  * @param ptr output buffer
yading@10:  * @param offset offset in the output buffer
yading@10:  * @param num_coefs number of input coefficents
yading@10:  * @param block_len input buffer length (2^n)
yading@10:  * @param frame_len_bits number of bits for escaped run codes
yading@10:  * @param coef_nb_bits number of bits for escaped level codes
yading@10:  * @return 0 on success, -1 otherwise
yading@10:  */
yading@10: int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
yading@10:                             VLC *vlc,
yading@10:                             const float *level_table, const uint16_t *run_table,
yading@10:                             int version, WMACoef *ptr, int offset,
yading@10:                             int num_coefs, int block_len, int frame_len_bits,
yading@10:                             int coef_nb_bits)
yading@10: {
yading@10:     int code, level, sign;
yading@10:     const uint32_t *ilvl = (const uint32_t*)level_table;
yading@10:     uint32_t *iptr = (uint32_t*)ptr;
yading@10:     const unsigned int coef_mask = block_len - 1;
yading@10:     for (; offset < num_coefs; offset++) {
yading@10:         code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
yading@10:         if (code > 1) {
yading@10:             /** normal code */
yading@10:             offset += run_table[code];
yading@10:             sign = get_bits1(gb) - 1;
yading@10:             iptr[offset & coef_mask] = ilvl[code] ^ sign<<31;
yading@10:         } else if (code == 1) {
yading@10:             /** EOB */
yading@10:             break;
yading@10:         } else {
yading@10:             /** escape */
yading@10:             if (!version) {
yading@10:                 level = get_bits(gb, coef_nb_bits);
yading@10:                 /** NOTE: this is rather suboptimal. reading
yading@10:                     block_len_bits would be better */
yading@10:                 offset += get_bits(gb, frame_len_bits);
yading@10:             } else {
yading@10:                 level = ff_wma_get_large_val(gb);
yading@10:                 /** escape decode */
yading@10:                 if (get_bits1(gb)) {
yading@10:                     if (get_bits1(gb)) {
yading@10:                         if (get_bits1(gb)) {
yading@10:                             av_log(avctx,AV_LOG_ERROR,
yading@10:                                 "broken escape sequence\n");
yading@10:                             return -1;
yading@10:                         } else
yading@10:                             offset += get_bits(gb, frame_len_bits) + 4;
yading@10:                     } else
yading@10:                         offset += get_bits(gb, 2) + 1;
yading@10:                 }
yading@10:             }
yading@10:             sign = get_bits1(gb) - 1;
yading@10:             ptr[offset & coef_mask] = (level^sign) - sign;
yading@10:         }
yading@10:     }
yading@10:     /** NOTE: EOB can be omitted */
yading@10:     if (offset > num_coefs) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");
yading@10:         return -1;
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }