diff options
Diffstat (limited to 'ffmpeg1/libavcodec/wma.c')
| -rw-r--r-- | ffmpeg1/libavcodec/wma.c | 488 |
1 files changed, 488 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/wma.c b/ffmpeg1/libavcodec/wma.c new file mode 100644 index 0000000..1e6ca61 --- /dev/null +++ b/ffmpeg1/libavcodec/wma.c @@ -0,0 +1,488 @@ +/* + * WMA compatible codec + * Copyright (c) 2002-2007 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 + */ + +#include "avcodec.h" +#include "sinewin.h" +#include "wma.h" +#include "wma_common.h" +#include "wmadata.h" + +#undef NDEBUG +#include <assert.h> + +/* XXX: use same run/length optimization as mpeg decoders */ +//FIXME maybe split decode / encode or pass flag +static void init_coef_vlc(VLC *vlc, uint16_t **prun_table, + float **plevel_table, uint16_t **pint_table, + const CoefVLCTable *vlc_table) +{ + int n = vlc_table->n; + const uint8_t *table_bits = vlc_table->huffbits; + const uint32_t *table_codes = vlc_table->huffcodes; + const uint16_t *levels_table = vlc_table->levels; + uint16_t *run_table, *level_table, *int_table; + float *flevel_table; + int i, l, j, k, level; + + init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0); + + run_table = av_malloc(n * sizeof(uint16_t)); + level_table = av_malloc(n * sizeof(uint16_t)); + flevel_table= av_malloc(n * sizeof(*flevel_table)); + int_table = av_malloc(n * sizeof(uint16_t)); + i = 2; + level = 1; + k = 0; + while (i < n) { + int_table[k] = i; + l = levels_table[k++]; + for (j = 0; j < l; j++) { + run_table[i] = j; + level_table[i] = level; + flevel_table[i]= level; + i++; + } + level++; + } + *prun_table = run_table; + *plevel_table = flevel_table; + *pint_table = int_table; + av_free(level_table); +} + +int ff_wma_init(AVCodecContext *avctx, int flags2) +{ + WMACodecContext *s = avctx->priv_data; + int i; + float bps1, high_freq; + volatile float bps; + int sample_rate1; + int coef_vlc_table; + + if ( avctx->sample_rate <= 0 || avctx->sample_rate > 50000 + || avctx->channels <= 0 || avctx->channels > 2 + || avctx->bit_rate <= 0) + return -1; + + ff_fmt_convert_init(&s->fmt_conv, avctx); + avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT); + + if (avctx->codec->id == AV_CODEC_ID_WMAV1) { + s->version = 1; + } else { + s->version = 2; + } + + /* compute MDCT block size */ + s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate, + s->version, 0); + 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; + + s->frame_len = 1 << s->frame_len_bits; + if (s->use_variable_block_len) { + int nb_max, nb; + nb = ((flags2 >> 3) & 3) + 1; + if ((avctx->bit_rate / avctx->channels) >= 32000) + nb += 2; + nb_max = s->frame_len_bits - BLOCK_MIN_BITS; + if (nb > nb_max) + nb = nb_max; + s->nb_block_sizes = nb + 1; + } else { + s->nb_block_sizes = 1; + } + + /* init rate dependent parameters */ + s->use_noise_coding = 1; + high_freq = avctx->sample_rate * 0.5; + + /* if version 2, then the rates are normalized */ + sample_rate1 = avctx->sample_rate; + if (s->version == 2) { + if (sample_rate1 >= 44100) { + sample_rate1 = 44100; + } else if (sample_rate1 >= 22050) { + sample_rate1 = 22050; + } else if (sample_rate1 >= 16000) { + sample_rate1 = 16000; + } else if (sample_rate1 >= 11025) { + sample_rate1 = 11025; + } else if (sample_rate1 >= 8000) { + sample_rate1 = 8000; + } + } + + bps = (float)avctx->bit_rate / (float)(avctx->channels * avctx->sample_rate); + s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2; + if (s->byte_offset_bits + 3 > MIN_CACHE_BITS) { + av_log(avctx, AV_LOG_ERROR, "byte_offset_bits %d is too large\n", s->byte_offset_bits); + return AVERROR_PATCHWELCOME; + } + + /* compute high frequency value and choose if noise coding should + be activated */ + bps1 = bps; + if (avctx->channels == 2) + bps1 = bps * 1.6; + if (sample_rate1 == 44100) { + if (bps1 >= 0.61) { + s->use_noise_coding = 0; + } else { + high_freq = high_freq * 0.4; + } + } else if (sample_rate1 == 22050) { + if (bps1 >= 1.16) { + s->use_noise_coding = 0; + } else if (bps1 >= 0.72) { + high_freq = high_freq * 0.7; + } else { + high_freq = high_freq * 0.6; + } + } else if (sample_rate1 == 16000) { + if (bps > 0.5) { + high_freq = high_freq * 0.5; + } else { + high_freq = high_freq * 0.3; + } + } else if (sample_rate1 == 11025) { + high_freq = high_freq * 0.7; + } else if (sample_rate1 == 8000) { + if (bps <= 0.625) { + high_freq = high_freq * 0.5; + } else if (bps > 0.75) { + s->use_noise_coding = 0; + } else { + high_freq = high_freq * 0.65; + } + } else { + if (bps >= 0.8) { + high_freq = high_freq * 0.75; + } else if (bps >= 0.6) { + high_freq = high_freq * 0.6; + } else { + high_freq = high_freq * 0.5; + } + } + av_dlog(s->avctx, "flags2=0x%x\n", flags2); + av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n", + s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate, + avctx->block_align); + av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n", + bps, bps1, high_freq, s->byte_offset_bits); + av_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n", + s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes); + + /* compute the scale factor band sizes for each MDCT block size */ + { + int a, b, pos, lpos, k, block_len, i, j, n; + const uint8_t *table; + + if (s->version == 1) { + s->coefs_start = 3; + } else { + s->coefs_start = 0; + } + for (k = 0; k < s->nb_block_sizes; k++) { + block_len = s->frame_len >> k; + + if (s->version == 1) { + lpos = 0; + for (i = 0; i < 25; i++) { + a = ff_wma_critical_freqs[i]; + b = avctx->sample_rate; + pos = ((block_len * 2 * a) + (b >> 1)) / b; + if (pos > block_len) + pos = block_len; + s->exponent_bands[0][i] = pos - lpos; + if (pos >= block_len) { + i++; + break; + } + lpos = pos; + } + s->exponent_sizes[0] = i; + } else { + /* hardcoded tables */ + table = NULL; + a = s->frame_len_bits - BLOCK_MIN_BITS - k; + if (a < 3) { + if (avctx->sample_rate >= 44100) { + table = exponent_band_44100[a]; + } else if (avctx->sample_rate >= 32000) { + table = exponent_band_32000[a]; + } else if (avctx->sample_rate >= 22050) { + table = exponent_band_22050[a]; + } + } + if (table) { + n = *table++; + for (i = 0; i < n; i++) + s->exponent_bands[k][i] = table[i]; + s->exponent_sizes[k] = n; + } else { + j = 0; + lpos = 0; + for (i = 0; i < 25; i++) { + a = ff_wma_critical_freqs[i]; + b = avctx->sample_rate; + pos = ((block_len * 2 * a) + (b << 1)) / (4 * b); + pos <<= 2; + if (pos > block_len) + pos = block_len; + if (pos > lpos) + s->exponent_bands[k][j++] = pos - lpos; + if (pos >= block_len) + break; + lpos = pos; + } + s->exponent_sizes[k] = j; + } + } + + /* max number of coefs */ + s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k; + /* high freq computation */ + s->high_band_start[k] = (int)((block_len * 2 * high_freq) / + avctx->sample_rate + 0.5); + n = s->exponent_sizes[k]; + j = 0; + pos = 0; + for (i = 0; i < n; i++) { + int start, end; + start = pos; + pos += s->exponent_bands[k][i]; + end = pos; + if (start < s->high_band_start[k]) + start = s->high_band_start[k]; + if (end > s->coefs_end[k]) + end = s->coefs_end[k]; + if (end > start) + s->exponent_high_bands[k][j++] = end - start; + } + s->exponent_high_sizes[k] = j; +#if 0 + tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ", + s->frame_len >> k, + s->coefs_end[k], + s->high_band_start[k], + s->exponent_high_sizes[k]); + for (j = 0; j < s->exponent_high_sizes[k]; j++) + tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]); + tprintf(s->avctx, "\n"); +#endif + } + } + +#ifdef TRACE + { + int i, j; + for (i = 0; i < s->nb_block_sizes; i++) { + tprintf(s->avctx, "%5d: n=%2d:", + s->frame_len >> i, + s->exponent_sizes[i]); + for (j = 0; j < s->exponent_sizes[i]; j++) + tprintf(s->avctx, " %d", s->exponent_bands[i][j]); + tprintf(s->avctx, "\n"); + } + } +#endif + + /* init MDCT windows : simple sinus window */ + for (i = 0; i < s->nb_block_sizes; i++) { + ff_init_ff_sine_windows(s->frame_len_bits - i); + s->windows[i] = ff_sine_windows[s->frame_len_bits - i]; + } + + s->reset_block_lengths = 1; + + if (s->use_noise_coding) { + + /* init the noise generator */ + if (s->use_exp_vlc) { + s->noise_mult = 0.02; + } else { + s->noise_mult = 0.04; + } + +#ifdef TRACE + for (i = 0; i < NOISE_TAB_SIZE; i++) + s->noise_table[i] = 1.0 * s->noise_mult; +#else + { + unsigned int seed; + float norm; + seed = 1; + norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult; + for (i = 0; i < NOISE_TAB_SIZE; i++) { + seed = seed * 314159 + 1; + s->noise_table[i] = (float)((int)seed) * norm; + } + } +#endif + } + + /* choose the VLC tables for the coefficients */ + coef_vlc_table = 2; + if (avctx->sample_rate >= 32000) { + if (bps1 < 0.72) { + coef_vlc_table = 0; + } else if (bps1 < 1.16) { + coef_vlc_table = 1; + } + } + s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ]; + s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1]; + init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0], + s->coef_vlcs[0]); + init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1], + s->coef_vlcs[1]); + + return 0; +} + +int ff_wma_total_gain_to_bits(int total_gain) +{ + if (total_gain < 15) return 13; + else if (total_gain < 32) return 12; + else if (total_gain < 40) return 11; + else if (total_gain < 45) return 10; + else return 9; +} + +int ff_wma_end(AVCodecContext *avctx) +{ + WMACodecContext *s = avctx->priv_data; + int i; + + for (i = 0; i < s->nb_block_sizes; i++) + ff_mdct_end(&s->mdct_ctx[i]); + + if (s->use_exp_vlc) { + ff_free_vlc(&s->exp_vlc); + } + if (s->use_noise_coding) { + ff_free_vlc(&s->hgain_vlc); + } + for (i = 0; i < 2; i++) { + ff_free_vlc(&s->coef_vlc[i]); + av_free(s->run_table[i]); + av_free(s->level_table[i]); + av_free(s->int_table[i]); + } + + return 0; +} + +/** + * Decode an uncompressed coefficient. + * @param gb GetBitContext + * @return the decoded coefficient + */ +unsigned int ff_wma_get_large_val(GetBitContext* gb) +{ + /** consumes up to 34 bits */ + int n_bits = 8; + /** decode length */ + if (get_bits1(gb)) { + n_bits += 8; + if (get_bits1(gb)) { + n_bits += 8; + if (get_bits1(gb)) { + n_bits += 7; + } + } + } + return get_bits_long(gb, n_bits); +} + +/** + * Decode run level compressed coefficients. + * @param avctx codec context + * @param gb bitstream reader context + * @param vlc vlc table for get_vlc2 + * @param level_table level codes + * @param run_table run codes + * @param version 0 for wma1,2 1 for wmapro + * @param ptr output buffer + * @param offset offset in the output buffer + * @param num_coefs number of input coefficents + * @param block_len input buffer length (2^n) + * @param frame_len_bits number of bits for escaped run codes + * @param coef_nb_bits number of bits for escaped level codes + * @return 0 on success, -1 otherwise + */ +int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb, + VLC *vlc, + const float *level_table, const uint16_t *run_table, + int version, WMACoef *ptr, int offset, + int num_coefs, int block_len, int frame_len_bits, + int coef_nb_bits) +{ + int code, level, sign; + const uint32_t *ilvl = (const uint32_t*)level_table; + uint32_t *iptr = (uint32_t*)ptr; + const unsigned int coef_mask = block_len - 1; + for (; offset < num_coefs; offset++) { + code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX); + if (code > 1) { + /** normal code */ + offset += run_table[code]; + sign = get_bits1(gb) - 1; + iptr[offset & coef_mask] = ilvl[code] ^ sign<<31; + } else if (code == 1) { + /** EOB */ + break; + } else { + /** escape */ + if (!version) { + level = get_bits(gb, coef_nb_bits); + /** NOTE: this is rather suboptimal. reading + block_len_bits would be better */ + offset += get_bits(gb, frame_len_bits); + } else { + level = ff_wma_get_large_val(gb); + /** escape decode */ + if (get_bits1(gb)) { + if (get_bits1(gb)) { + if (get_bits1(gb)) { + av_log(avctx,AV_LOG_ERROR, + "broken escape sequence\n"); + return -1; + } else + offset += get_bits(gb, frame_len_bits) + 4; + } else + offset += get_bits(gb, 2) + 1; + } + } + sign = get_bits1(gb) - 1; + ptr[offset & coef_mask] = (level^sign) - sign; + } + } + /** NOTE: EOB can be omitted */ + if (offset > num_coefs) { + av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n"); + return -1; + } + + return 0; +} |
