487 lines
16 KiB
C
487 lines
16 KiB
C
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/*
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* WMA compatible codec
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* Copyright (c) 2002-2007 The FFmpeg Project
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "libavutil/attributes.h"
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#include "avcodec.h"
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#include "internal.h"
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#include "sinewin.h"
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#include "wma.h"
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#include "wma_common.h"
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#include "wma_freqs.h"
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#include "wmadata.h"
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/* XXX: use same run/length optimization as mpeg decoders */
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// FIXME maybe split decode / encode or pass flag
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static av_cold int init_coef_vlc(VLC *vlc, uint16_t **prun_table,
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float **plevel_table, uint16_t **pint_table,
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const CoefVLCTable *vlc_table)
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{
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int n = vlc_table->n;
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const uint8_t *table_bits = vlc_table->huffbits;
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const uint32_t *table_codes = vlc_table->huffcodes;
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const uint16_t *levels_table = vlc_table->levels;
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uint16_t *run_table, *level_table, *int_table;
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float *flevel_table;
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int i, l, j, k, level;
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init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
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run_table = av_malloc_array(n, sizeof(uint16_t));
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level_table = av_malloc_array(n, sizeof(uint16_t));
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flevel_table = av_malloc_array(n, sizeof(*flevel_table));
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int_table = av_malloc_array(n, sizeof(uint16_t));
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if (!run_table || !level_table || !flevel_table || !int_table) {
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av_freep(&run_table);
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av_freep(&level_table);
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av_freep(&flevel_table);
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av_freep(&int_table);
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return AVERROR(ENOMEM);
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}
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i = 2;
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level = 1;
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k = 0;
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while (i < n) {
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int_table[k] = i;
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l = levels_table[k++];
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for (j = 0; j < l; j++) {
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run_table[i] = j;
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level_table[i] = level;
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flevel_table[i] = level;
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i++;
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}
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level++;
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}
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*prun_table = run_table;
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*plevel_table = flevel_table;
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*pint_table = int_table;
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av_free(level_table);
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return 0;
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}
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av_cold int ff_wma_init(AVCodecContext *avctx, int flags2)
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{
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WMACodecContext *s = avctx->priv_data;
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int i, ret;
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float bps1, high_freq;
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volatile float bps;
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int sample_rate1;
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int coef_vlc_table;
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if (avctx->sample_rate <= 0 || avctx->sample_rate > 50000 ||
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avctx->channels <= 0 || avctx->channels > 2 ||
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avctx->bit_rate <= 0)
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return -1;
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if (avctx->codec->id == AV_CODEC_ID_WMAV1)
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s->version = 1;
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else
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s->version = 2;
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/* compute MDCT block size */
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s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
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s->version, 0);
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s->next_block_len_bits = s->frame_len_bits;
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s->prev_block_len_bits = s->frame_len_bits;
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s->block_len_bits = s->frame_len_bits;
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s->frame_len = 1 << s->frame_len_bits;
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if (s->use_variable_block_len) {
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int nb_max, nb;
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nb = ((flags2 >> 3) & 3) + 1;
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if ((avctx->bit_rate / avctx->channels) >= 32000)
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nb += 2;
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nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
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if (nb > nb_max)
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nb = nb_max;
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s->nb_block_sizes = nb + 1;
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} else
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s->nb_block_sizes = 1;
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/* init rate dependent parameters */
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s->use_noise_coding = 1;
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high_freq = avctx->sample_rate * 0.5;
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/* if version 2, then the rates are normalized */
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sample_rate1 = avctx->sample_rate;
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if (s->version == 2) {
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if (sample_rate1 >= 44100)
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sample_rate1 = 44100;
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else if (sample_rate1 >= 22050)
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sample_rate1 = 22050;
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else if (sample_rate1 >= 16000)
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sample_rate1 = 16000;
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else if (sample_rate1 >= 11025)
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sample_rate1 = 11025;
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else if (sample_rate1 >= 8000)
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sample_rate1 = 8000;
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}
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bps = (float) avctx->bit_rate /
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(float) (avctx->channels * avctx->sample_rate);
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s->byte_offset_bits = av_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
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if (s->byte_offset_bits + 3 > MIN_CACHE_BITS) {
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av_log(avctx, AV_LOG_ERROR, "byte_offset_bits %d is too large\n", s->byte_offset_bits);
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return AVERROR_PATCHWELCOME;
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}
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/* compute high frequency value and choose if noise coding should
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* be activated */
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bps1 = bps;
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if (avctx->channels == 2)
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bps1 = bps * 1.6;
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if (sample_rate1 == 44100) {
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if (bps1 >= 0.61)
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s->use_noise_coding = 0;
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else
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high_freq = high_freq * 0.4;
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} else if (sample_rate1 == 22050) {
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if (bps1 >= 1.16)
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s->use_noise_coding = 0;
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else if (bps1 >= 0.72)
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high_freq = high_freq * 0.7;
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else
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high_freq = high_freq * 0.6;
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} else if (sample_rate1 == 16000) {
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if (bps > 0.5)
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high_freq = high_freq * 0.5;
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else
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high_freq = high_freq * 0.3;
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} else if (sample_rate1 == 11025)
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high_freq = high_freq * 0.7;
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else if (sample_rate1 == 8000) {
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if (bps <= 0.625)
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high_freq = high_freq * 0.5;
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else if (bps > 0.75)
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s->use_noise_coding = 0;
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else
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high_freq = high_freq * 0.65;
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} else {
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if (bps >= 0.8)
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high_freq = high_freq * 0.75;
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else if (bps >= 0.6)
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high_freq = high_freq * 0.6;
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else
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high_freq = high_freq * 0.5;
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}
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ff_dlog(s->avctx, "flags2=0x%x\n", flags2);
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ff_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%"PRId64" block_align=%d\n",
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s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate,
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avctx->block_align);
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ff_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
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bps, bps1, high_freq, s->byte_offset_bits);
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ff_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
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s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
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/* compute the scale factor band sizes for each MDCT block size */
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{
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int a, b, pos, lpos, k, block_len, i, j, n;
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const uint8_t *table;
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if (s->version == 1)
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s->coefs_start = 3;
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else
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s->coefs_start = 0;
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for (k = 0; k < s->nb_block_sizes; k++) {
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block_len = s->frame_len >> k;
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if (s->version == 1) {
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lpos = 0;
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for (i = 0; i < 25; i++) {
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a = ff_wma_critical_freqs[i];
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b = avctx->sample_rate;
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pos = ((block_len * 2 * a) + (b >> 1)) / b;
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if (pos > block_len)
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pos = block_len;
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s->exponent_bands[0][i] = pos - lpos;
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if (pos >= block_len) {
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i++;
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break;
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}
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lpos = pos;
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}
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s->exponent_sizes[0] = i;
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} else {
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/* hardcoded tables */
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table = NULL;
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a = s->frame_len_bits - BLOCK_MIN_BITS - k;
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if (a < 3) {
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if (avctx->sample_rate >= 44100)
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table = exponent_band_44100[a];
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else if (avctx->sample_rate >= 32000)
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table = exponent_band_32000[a];
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else if (avctx->sample_rate >= 22050)
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table = exponent_band_22050[a];
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}
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if (table) {
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n = *table++;
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for (i = 0; i < n; i++)
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s->exponent_bands[k][i] = table[i];
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s->exponent_sizes[k] = n;
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} else {
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j = 0;
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lpos = 0;
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for (i = 0; i < 25; i++) {
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a = ff_wma_critical_freqs[i];
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b = avctx->sample_rate;
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pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
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pos <<= 2;
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if (pos > block_len)
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pos = block_len;
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if (pos > lpos)
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s->exponent_bands[k][j++] = pos - lpos;
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if (pos >= block_len)
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break;
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lpos = pos;
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}
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s->exponent_sizes[k] = j;
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}
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}
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/* max number of coefs */
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s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
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/* high freq computation */
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s->high_band_start[k] = (int) ((block_len * 2 * high_freq) /
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avctx->sample_rate + 0.5);
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n = s->exponent_sizes[k];
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j = 0;
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pos = 0;
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for (i = 0; i < n; i++) {
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int start, end;
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start = pos;
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pos += s->exponent_bands[k][i];
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end = pos;
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if (start < s->high_band_start[k])
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start = s->high_band_start[k];
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if (end > s->coefs_end[k])
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end = s->coefs_end[k];
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if (end > start)
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s->exponent_high_bands[k][j++] = end - start;
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}
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s->exponent_high_sizes[k] = j;
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}
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}
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#ifdef TRACE
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{
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int i, j;
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for (i = 0; i < s->nb_block_sizes; i++) {
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ff_tlog(s->avctx, "%5d: n=%2d:",
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s->frame_len >> i,
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s->exponent_sizes[i]);
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for (j = 0; j < s->exponent_sizes[i]; j++)
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ff_tlog(s->avctx, " %d", s->exponent_bands[i][j]);
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ff_tlog(s->avctx, "\n");
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}
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}
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#endif /* TRACE */
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/* init MDCT windows : simple sine window */
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for (i = 0; i < s->nb_block_sizes; i++) {
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ff_init_ff_sine_windows(s->frame_len_bits - i);
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s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
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}
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s->reset_block_lengths = 1;
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if (s->use_noise_coding) {
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/* init the noise generator */
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if (s->use_exp_vlc)
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s->noise_mult = 0.02;
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else
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s->noise_mult = 0.04;
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#ifdef TRACE
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for (i = 0; i < NOISE_TAB_SIZE; i++)
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s->noise_table[i] = 1.0 * s->noise_mult;
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#else
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{
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unsigned int seed;
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float norm;
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seed = 1;
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norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
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for (i = 0; i < NOISE_TAB_SIZE; i++) {
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seed = seed * 314159 + 1;
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s->noise_table[i] = (float) ((int) seed) * norm;
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}
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}
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#endif /* TRACE */
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}
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s->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT);
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if (!s->fdsp)
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return AVERROR(ENOMEM);
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/* choose the VLC tables for the coefficients */
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coef_vlc_table = 2;
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if (avctx->sample_rate >= 32000) {
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if (bps1 < 0.72)
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coef_vlc_table = 0;
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else if (bps1 < 1.16)
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coef_vlc_table = 1;
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}
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s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
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s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
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ret = init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
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&s->int_table[0], s->coef_vlcs[0]);
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||
|
|
if (ret < 0)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
return init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
|
||
|
|
&s->int_table[1], s->coef_vlcs[1]);
|
||
|
|
}
|
||
|
|
|
||
|
|
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_freep(&s->run_table[i]);
|
||
|
|
av_freep(&s->level_table[i]);
|
||
|
|
av_freep(&s->int_table[i]);
|
||
|
|
}
|
||
|
|
av_freep(&s->fdsp);
|
||
|
|
|
||
|
|
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 coefficients
|
||
|
|
* @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 & 0x80000000);
|
||
|
|
} 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 (%d > %d) in spectral RLE, ignoring\n",
|
||
|
|
offset,
|
||
|
|
num_coefs
|
||
|
|
);
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|