mirror of
https://github.com/FFmpeg/FFmpeg.git
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1012 lines
31 KiB
C
1012 lines
31 KiB
C
/*
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* IMC compatible decoder
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* Copyright (c) 2002-2004 Maxim Poliakovski
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* Copyright (c) 2006 Benjamin Larsson
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* Copyright (c) 2006 Konstantin Shishkov
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*
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* This file is part of Libav.
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*
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* Libav 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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* Libav 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 Libav; 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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/**
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* @file
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* IMC - Intel Music Coder
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* A mdct based codec using a 256 points large transform
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* divided into 32 bands with some mix of scale factors.
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* Only mono is supported.
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*
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*/
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#include <math.h>
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#include <stddef.h>
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#include <stdio.h>
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#include "libavutil/channel_layout.h"
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#include "libavutil/float_dsp.h"
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#include "libavutil/internal.h"
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#include "avcodec.h"
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#include "get_bits.h"
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#include "dsputil.h"
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#include "fft.h"
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#include "internal.h"
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#include "sinewin.h"
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#include "imcdata.h"
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#define IMC_BLOCK_SIZE 64
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#define IMC_FRAME_ID 0x21
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#define BANDS 32
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#define COEFFS 256
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typedef struct IMCChannel {
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float old_floor[BANDS];
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float flcoeffs1[BANDS];
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float flcoeffs2[BANDS];
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float flcoeffs3[BANDS];
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float flcoeffs4[BANDS];
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float flcoeffs5[BANDS];
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float flcoeffs6[BANDS];
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float CWdecoded[COEFFS];
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int bandWidthT[BANDS]; ///< codewords per band
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int bitsBandT[BANDS]; ///< how many bits per codeword in band
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int CWlengthT[COEFFS]; ///< how many bits in each codeword
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int levlCoeffBuf[BANDS];
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int bandFlagsBuf[BANDS]; ///< flags for each band
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int sumLenArr[BANDS]; ///< bits for all coeffs in band
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int skipFlagRaw[BANDS]; ///< skip flags are stored in raw form or not
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int skipFlagBits[BANDS]; ///< bits used to code skip flags
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int skipFlagCount[BANDS]; ///< skipped coeffients per band
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int skipFlags[COEFFS]; ///< skip coefficient decoding or not
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int codewords[COEFFS]; ///< raw codewords read from bitstream
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float last_fft_im[COEFFS];
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int decoder_reset;
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} IMCChannel;
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typedef struct {
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IMCChannel chctx[2];
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/** MDCT tables */
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//@{
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float mdct_sine_window[COEFFS];
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float post_cos[COEFFS];
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float post_sin[COEFFS];
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float pre_coef1[COEFFS];
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float pre_coef2[COEFFS];
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//@}
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float sqrt_tab[30];
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GetBitContext gb;
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DSPContext dsp;
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AVFloatDSPContext fdsp;
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FFTContext fft;
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DECLARE_ALIGNED(32, FFTComplex, samples)[COEFFS / 2];
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float *out_samples;
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int8_t cyclTab[32], cyclTab2[32];
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float weights1[31], weights2[31];
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} IMCContext;
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static VLC huffman_vlc[4][4];
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#define VLC_TABLES_SIZE 9512
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static const int vlc_offsets[17] = {
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0, 640, 1156, 1732, 2308, 2852, 3396, 3924,
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4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE
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};
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static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2];
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static inline double freq2bark(double freq)
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{
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return 3.5 * atan((freq / 7500.0) * (freq / 7500.0)) + 13.0 * atan(freq * 0.00076);
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}
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static av_cold void iac_generate_tabs(IMCContext *q, int sampling_rate)
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{
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double freqmin[32], freqmid[32], freqmax[32];
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double scale = sampling_rate / (256.0 * 2.0 * 2.0);
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double nyquist_freq = sampling_rate * 0.5;
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double freq, bark, prev_bark = 0, tf, tb;
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int i, j;
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for (i = 0; i < 32; i++) {
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freq = (band_tab[i] + band_tab[i + 1] - 1) * scale;
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bark = freq2bark(freq);
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if (i > 0) {
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tb = bark - prev_bark;
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q->weights1[i - 1] = pow(10.0, -1.0 * tb);
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q->weights2[i - 1] = pow(10.0, -2.7 * tb);
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}
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prev_bark = bark;
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freqmid[i] = freq;
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tf = freq;
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while (tf < nyquist_freq) {
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tf += 0.5;
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tb = freq2bark(tf);
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if (tb > bark + 0.5)
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break;
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}
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freqmax[i] = tf;
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tf = freq;
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while (tf > 0.0) {
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tf -= 0.5;
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tb = freq2bark(tf);
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if (tb <= bark - 0.5)
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break;
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}
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freqmin[i] = tf;
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}
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for (i = 0; i < 32; i++) {
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freq = freqmax[i];
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for (j = 31; j > 0 && freq <= freqmid[j]; j--);
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q->cyclTab[i] = j + 1;
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freq = freqmin[i];
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for (j = 0; j < 32 && freq >= freqmid[j]; j++);
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q->cyclTab2[i] = j - 1;
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}
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}
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static av_cold int imc_decode_init(AVCodecContext *avctx)
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{
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int i, j, ret;
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IMCContext *q = avctx->priv_data;
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double r1, r2;
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if (avctx->codec_id == AV_CODEC_ID_IMC)
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avctx->channels = 1;
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if (avctx->channels > 2) {
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avpriv_request_sample(avctx, "Number of channels > 2");
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return AVERROR_PATCHWELCOME;
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}
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for (j = 0; j < avctx->channels; j++) {
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q->chctx[j].decoder_reset = 1;
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for (i = 0; i < BANDS; i++)
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q->chctx[j].old_floor[i] = 1.0;
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for (i = 0; i < COEFFS / 2; i++)
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q->chctx[j].last_fft_im[i] = 0;
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}
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/* Build mdct window, a simple sine window normalized with sqrt(2) */
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ff_sine_window_init(q->mdct_sine_window, COEFFS);
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for (i = 0; i < COEFFS; i++)
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q->mdct_sine_window[i] *= sqrt(2.0);
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for (i = 0; i < COEFFS / 2; i++) {
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q->post_cos[i] = (1.0f / 32768) * cos(i / 256.0 * M_PI);
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q->post_sin[i] = (1.0f / 32768) * sin(i / 256.0 * M_PI);
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r1 = sin((i * 4.0 + 1.0) / 1024.0 * M_PI);
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r2 = cos((i * 4.0 + 1.0) / 1024.0 * M_PI);
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if (i & 0x1) {
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q->pre_coef1[i] = (r1 + r2) * sqrt(2.0);
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q->pre_coef2[i] = -(r1 - r2) * sqrt(2.0);
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} else {
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q->pre_coef1[i] = -(r1 + r2) * sqrt(2.0);
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q->pre_coef2[i] = (r1 - r2) * sqrt(2.0);
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}
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}
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/* Generate a square root table */
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for (i = 0; i < 30; i++)
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q->sqrt_tab[i] = sqrt(i);
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/* initialize the VLC tables */
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for (i = 0; i < 4 ; i++) {
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for (j = 0; j < 4; j++) {
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huffman_vlc[i][j].table = &vlc_tables[vlc_offsets[i * 4 + j]];
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huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j];
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init_vlc(&huffman_vlc[i][j], 9, imc_huffman_sizes[i],
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imc_huffman_lens[i][j], 1, 1,
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imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC);
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}
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}
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if (avctx->codec_id == AV_CODEC_ID_IAC) {
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iac_generate_tabs(q, avctx->sample_rate);
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} else {
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memcpy(q->cyclTab, cyclTab, sizeof(cyclTab));
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memcpy(q->cyclTab2, cyclTab2, sizeof(cyclTab2));
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memcpy(q->weights1, imc_weights1, sizeof(imc_weights1));
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memcpy(q->weights2, imc_weights2, sizeof(imc_weights2));
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}
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if ((ret = ff_fft_init(&q->fft, 7, 1))) {
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av_log(avctx, AV_LOG_INFO, "FFT init failed\n");
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return ret;
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}
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ff_dsputil_init(&q->dsp, avctx);
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avpriv_float_dsp_init(&q->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
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avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
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avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO
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: AV_CH_LAYOUT_STEREO;
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return 0;
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}
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static void imc_calculate_coeffs(IMCContext *q, float *flcoeffs1,
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float *flcoeffs2, int *bandWidthT,
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float *flcoeffs3, float *flcoeffs5)
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{
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float workT1[BANDS];
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float workT2[BANDS];
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float workT3[BANDS];
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float snr_limit = 1.e-30;
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float accum = 0.0;
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int i, cnt2;
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for (i = 0; i < BANDS; i++) {
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flcoeffs5[i] = workT2[i] = 0.0;
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if (bandWidthT[i]) {
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workT1[i] = flcoeffs1[i] * flcoeffs1[i];
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flcoeffs3[i] = 2.0 * flcoeffs2[i];
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} else {
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workT1[i] = 0.0;
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flcoeffs3[i] = -30000.0;
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}
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workT3[i] = bandWidthT[i] * workT1[i] * 0.01;
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if (workT3[i] <= snr_limit)
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workT3[i] = 0.0;
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}
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for (i = 0; i < BANDS; i++) {
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for (cnt2 = i; cnt2 < q->cyclTab[i]; cnt2++)
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flcoeffs5[cnt2] = flcoeffs5[cnt2] + workT3[i];
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workT2[cnt2 - 1] = workT2[cnt2 - 1] + workT3[i];
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}
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for (i = 1; i < BANDS; i++) {
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accum = (workT2[i - 1] + accum) * q->weights1[i - 1];
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flcoeffs5[i] += accum;
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}
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for (i = 0; i < BANDS; i++)
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workT2[i] = 0.0;
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for (i = 0; i < BANDS; i++) {
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for (cnt2 = i - 1; cnt2 > q->cyclTab2[i]; cnt2--)
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flcoeffs5[cnt2] += workT3[i];
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workT2[cnt2+1] += workT3[i];
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}
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accum = 0.0;
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for (i = BANDS-2; i >= 0; i--) {
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accum = (workT2[i+1] + accum) * q->weights2[i];
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flcoeffs5[i] += accum;
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// there is missing code here, but it seems to never be triggered
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}
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}
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static void imc_read_level_coeffs(IMCContext *q, int stream_format_code,
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int *levlCoeffs)
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{
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int i;
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VLC *hufftab[4];
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int start = 0;
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const uint8_t *cb_sel;
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int s;
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s = stream_format_code >> 1;
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hufftab[0] = &huffman_vlc[s][0];
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hufftab[1] = &huffman_vlc[s][1];
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hufftab[2] = &huffman_vlc[s][2];
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hufftab[3] = &huffman_vlc[s][3];
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cb_sel = imc_cb_select[s];
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if (stream_format_code & 4)
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start = 1;
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if (start)
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levlCoeffs[0] = get_bits(&q->gb, 7);
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for (i = start; i < BANDS; i++) {
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levlCoeffs[i] = get_vlc2(&q->gb, hufftab[cb_sel[i]]->table,
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hufftab[cb_sel[i]]->bits, 2);
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if (levlCoeffs[i] == 17)
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levlCoeffs[i] += get_bits(&q->gb, 4);
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}
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}
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static void imc_decode_level_coefficients(IMCContext *q, int *levlCoeffBuf,
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float *flcoeffs1, float *flcoeffs2)
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{
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int i, level;
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float tmp, tmp2;
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// maybe some frequency division thingy
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flcoeffs1[0] = 20000.0 / pow (2, levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125
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flcoeffs2[0] = log2f(flcoeffs1[0]);
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tmp = flcoeffs1[0];
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tmp2 = flcoeffs2[0];
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for (i = 1; i < BANDS; i++) {
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level = levlCoeffBuf[i];
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if (level == 16) {
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flcoeffs1[i] = 1.0;
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flcoeffs2[i] = 0.0;
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} else {
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if (level < 17)
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level -= 7;
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else if (level <= 24)
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level -= 32;
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else
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level -= 16;
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tmp *= imc_exp_tab[15 + level];
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tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25
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flcoeffs1[i] = tmp;
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flcoeffs2[i] = tmp2;
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}
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}
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}
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static void imc_decode_level_coefficients2(IMCContext *q, int *levlCoeffBuf,
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float *old_floor, float *flcoeffs1,
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float *flcoeffs2)
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{
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int i;
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/* FIXME maybe flag_buf = noise coding and flcoeffs1 = new scale factors
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* and flcoeffs2 old scale factors
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* might be incomplete due to a missing table that is in the binary code
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*/
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for (i = 0; i < BANDS; i++) {
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flcoeffs1[i] = 0;
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if (levlCoeffBuf[i] < 16) {
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flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i];
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flcoeffs2[i] = (levlCoeffBuf[i] - 7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25
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} else {
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flcoeffs1[i] = old_floor[i];
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}
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}
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}
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/**
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* Perform bit allocation depending on bits available
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*/
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static int bit_allocation(IMCContext *q, IMCChannel *chctx,
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int stream_format_code, int freebits, int flag)
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{
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int i, j;
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const float limit = -1.e20;
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float highest = 0.0;
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int indx;
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int t1 = 0;
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int t2 = 1;
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float summa = 0.0;
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int iacc = 0;
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int summer = 0;
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int rres, cwlen;
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float lowest = 1.e10;
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int low_indx = 0;
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float workT[32];
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int flg;
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int found_indx = 0;
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for (i = 0; i < BANDS; i++)
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highest = FFMAX(highest, chctx->flcoeffs1[i]);
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for (i = 0; i < BANDS - 1; i++)
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chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log2f(chctx->flcoeffs5[i]);
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chctx->flcoeffs4[BANDS - 1] = limit;
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highest = highest * 0.25;
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for (i = 0; i < BANDS; i++) {
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indx = -1;
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if ((band_tab[i + 1] - band_tab[i]) == chctx->bandWidthT[i])
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indx = 0;
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if ((band_tab[i + 1] - band_tab[i]) > chctx->bandWidthT[i])
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indx = 1;
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if (((band_tab[i + 1] - band_tab[i]) / 2) >= chctx->bandWidthT[i])
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indx = 2;
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if (indx == -1)
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return AVERROR_INVALIDDATA;
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chctx->flcoeffs4[i] += xTab[(indx * 2 + (chctx->flcoeffs1[i] < highest)) * 2 + flag];
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}
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if (stream_format_code & 0x2) {
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chctx->flcoeffs4[0] = limit;
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chctx->flcoeffs4[1] = limit;
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chctx->flcoeffs4[2] = limit;
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chctx->flcoeffs4[3] = limit;
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}
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for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS - 1; i++) {
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iacc += chctx->bandWidthT[i];
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summa += chctx->bandWidthT[i] * chctx->flcoeffs4[i];
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}
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if (!iacc)
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return AVERROR_INVALIDDATA;
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chctx->bandWidthT[BANDS - 1] = 0;
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summa = (summa * 0.5 - freebits) / iacc;
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for (i = 0; i < BANDS / 2; i++) {
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rres = summer - freebits;
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if ((rres >= -8) && (rres <= 8))
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break;
|
|
|
|
summer = 0;
|
|
iacc = 0;
|
|
|
|
for (j = (stream_format_code & 0x2) ? 4 : 0; j < BANDS; j++) {
|
|
cwlen = av_clipf(((chctx->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6);
|
|
|
|
chctx->bitsBandT[j] = cwlen;
|
|
summer += chctx->bandWidthT[j] * cwlen;
|
|
|
|
if (cwlen > 0)
|
|
iacc += chctx->bandWidthT[j];
|
|
}
|
|
|
|
flg = t2;
|
|
t2 = 1;
|
|
if (freebits < summer)
|
|
t2 = -1;
|
|
if (i == 0)
|
|
flg = t2;
|
|
if (flg != t2)
|
|
t1++;
|
|
|
|
summa = (float)(summer - freebits) / ((t1 + 1) * iacc) + summa;
|
|
}
|
|
|
|
for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS; i++) {
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++)
|
|
chctx->CWlengthT[j] = chctx->bitsBandT[i];
|
|
}
|
|
|
|
if (freebits > summer) {
|
|
for (i = 0; i < BANDS; i++) {
|
|
workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
|
|
: (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
|
|
}
|
|
|
|
highest = 0.0;
|
|
|
|
do {
|
|
if (highest <= -1.e20)
|
|
break;
|
|
|
|
found_indx = 0;
|
|
highest = -1.e20;
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (workT[i] > highest) {
|
|
highest = workT[i];
|
|
found_indx = i;
|
|
}
|
|
}
|
|
|
|
if (highest > -1.e20) {
|
|
workT[found_indx] -= 2.0;
|
|
if (++chctx->bitsBandT[found_indx] == 6)
|
|
workT[found_indx] = -1.e20;
|
|
|
|
for (j = band_tab[found_indx]; j < band_tab[found_indx + 1] && (freebits > summer); j++) {
|
|
chctx->CWlengthT[j]++;
|
|
summer++;
|
|
}
|
|
}
|
|
} while (freebits > summer);
|
|
}
|
|
if (freebits < summer) {
|
|
for (i = 0; i < BANDS; i++) {
|
|
workT[i] = chctx->bitsBandT[i] ? (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] + 1.585)
|
|
: 1.e20;
|
|
}
|
|
if (stream_format_code & 0x2) {
|
|
workT[0] = 1.e20;
|
|
workT[1] = 1.e20;
|
|
workT[2] = 1.e20;
|
|
workT[3] = 1.e20;
|
|
}
|
|
while (freebits < summer) {
|
|
lowest = 1.e10;
|
|
low_indx = 0;
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (workT[i] < lowest) {
|
|
lowest = workT[i];
|
|
low_indx = i;
|
|
}
|
|
}
|
|
// if (lowest >= 1.e10)
|
|
// break;
|
|
workT[low_indx] = lowest + 2.0;
|
|
|
|
if (!--chctx->bitsBandT[low_indx])
|
|
workT[low_indx] = 1.e20;
|
|
|
|
for (j = band_tab[low_indx]; j < band_tab[low_indx+1] && (freebits < summer); j++) {
|
|
if (chctx->CWlengthT[j] > 0) {
|
|
chctx->CWlengthT[j]--;
|
|
summer--;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void imc_get_skip_coeff(IMCContext *q, IMCChannel *chctx)
|
|
{
|
|
int i, j;
|
|
|
|
memset(chctx->skipFlagBits, 0, sizeof(chctx->skipFlagBits));
|
|
memset(chctx->skipFlagCount, 0, sizeof(chctx->skipFlagCount));
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (!chctx->bandFlagsBuf[i] || !chctx->bandWidthT[i])
|
|
continue;
|
|
|
|
if (!chctx->skipFlagRaw[i]) {
|
|
chctx->skipFlagBits[i] = band_tab[i + 1] - band_tab[i];
|
|
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
|
|
chctx->skipFlags[j] = get_bits1(&q->gb);
|
|
if (chctx->skipFlags[j])
|
|
chctx->skipFlagCount[i]++;
|
|
}
|
|
} else {
|
|
for (j = band_tab[i]; j < band_tab[i + 1] - 1; j += 2) {
|
|
if (!get_bits1(&q->gb)) { // 0
|
|
chctx->skipFlagBits[i]++;
|
|
chctx->skipFlags[j] = 1;
|
|
chctx->skipFlags[j + 1] = 1;
|
|
chctx->skipFlagCount[i] += 2;
|
|
} else {
|
|
if (get_bits1(&q->gb)) { // 11
|
|
chctx->skipFlagBits[i] += 2;
|
|
chctx->skipFlags[j] = 0;
|
|
chctx->skipFlags[j + 1] = 1;
|
|
chctx->skipFlagCount[i]++;
|
|
} else {
|
|
chctx->skipFlagBits[i] += 3;
|
|
chctx->skipFlags[j + 1] = 0;
|
|
if (!get_bits1(&q->gb)) { // 100
|
|
chctx->skipFlags[j] = 1;
|
|
chctx->skipFlagCount[i]++;
|
|
} else { // 101
|
|
chctx->skipFlags[j] = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (j < band_tab[i + 1]) {
|
|
chctx->skipFlagBits[i]++;
|
|
if ((chctx->skipFlags[j] = get_bits1(&q->gb)))
|
|
chctx->skipFlagCount[i]++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Increase highest' band coefficient sizes as some bits won't be used
|
|
*/
|
|
static void imc_adjust_bit_allocation(IMCContext *q, IMCChannel *chctx,
|
|
int summer)
|
|
{
|
|
float workT[32];
|
|
int corrected = 0;
|
|
int i, j;
|
|
float highest = 0;
|
|
int found_indx = 0;
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
workT[i] = (chctx->bitsBandT[i] == 6) ? -1.e20
|
|
: (chctx->bitsBandT[i] * -2 + chctx->flcoeffs4[i] - 0.415);
|
|
}
|
|
|
|
while (corrected < summer) {
|
|
if (highest <= -1.e20)
|
|
break;
|
|
|
|
highest = -1.e20;
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (workT[i] > highest) {
|
|
highest = workT[i];
|
|
found_indx = i;
|
|
}
|
|
}
|
|
|
|
if (highest > -1.e20) {
|
|
workT[found_indx] -= 2.0;
|
|
if (++(chctx->bitsBandT[found_indx]) == 6)
|
|
workT[found_indx] = -1.e20;
|
|
|
|
for (j = band_tab[found_indx]; j < band_tab[found_indx+1] && (corrected < summer); j++) {
|
|
if (!chctx->skipFlags[j] && (chctx->CWlengthT[j] < 6)) {
|
|
chctx->CWlengthT[j]++;
|
|
corrected++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void imc_imdct256(IMCContext *q, IMCChannel *chctx, int channels)
|
|
{
|
|
int i;
|
|
float re, im;
|
|
float *dst1 = q->out_samples;
|
|
float *dst2 = q->out_samples + (COEFFS - 1);
|
|
|
|
/* prerotation */
|
|
for (i = 0; i < COEFFS / 2; i++) {
|
|
q->samples[i].re = -(q->pre_coef1[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
|
|
(q->pre_coef2[i] * chctx->CWdecoded[i * 2]);
|
|
q->samples[i].im = (q->pre_coef2[i] * chctx->CWdecoded[COEFFS - 1 - i * 2]) -
|
|
(q->pre_coef1[i] * chctx->CWdecoded[i * 2]);
|
|
}
|
|
|
|
/* FFT */
|
|
q->fft.fft_permute(&q->fft, q->samples);
|
|
q->fft.fft_calc(&q->fft, q->samples);
|
|
|
|
/* postrotation, window and reorder */
|
|
for (i = 0; i < COEFFS / 2; i++) {
|
|
re = ( q->samples[i].re * q->post_cos[i]) + (-q->samples[i].im * q->post_sin[i]);
|
|
im = (-q->samples[i].im * q->post_cos[i]) - ( q->samples[i].re * q->post_sin[i]);
|
|
*dst1 = (q->mdct_sine_window[COEFFS - 1 - i * 2] * chctx->last_fft_im[i])
|
|
+ (q->mdct_sine_window[i * 2] * re);
|
|
*dst2 = (q->mdct_sine_window[i * 2] * chctx->last_fft_im[i])
|
|
- (q->mdct_sine_window[COEFFS - 1 - i * 2] * re);
|
|
dst1 += 2;
|
|
dst2 -= 2;
|
|
chctx->last_fft_im[i] = im;
|
|
}
|
|
}
|
|
|
|
static int inverse_quant_coeff(IMCContext *q, IMCChannel *chctx,
|
|
int stream_format_code)
|
|
{
|
|
int i, j;
|
|
int middle_value, cw_len, max_size;
|
|
const float *quantizer;
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
|
|
chctx->CWdecoded[j] = 0;
|
|
cw_len = chctx->CWlengthT[j];
|
|
|
|
if (cw_len <= 0 || chctx->skipFlags[j])
|
|
continue;
|
|
|
|
max_size = 1 << cw_len;
|
|
middle_value = max_size >> 1;
|
|
|
|
if (chctx->codewords[j] >= max_size || chctx->codewords[j] < 0)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if (cw_len >= 4) {
|
|
quantizer = imc_quantizer2[(stream_format_code & 2) >> 1];
|
|
if (chctx->codewords[j] >= middle_value)
|
|
chctx->CWdecoded[j] = quantizer[chctx->codewords[j] - 8] * chctx->flcoeffs6[i];
|
|
else
|
|
chctx->CWdecoded[j] = -quantizer[max_size - chctx->codewords[j] - 8 - 1] * chctx->flcoeffs6[i];
|
|
}else{
|
|
quantizer = imc_quantizer1[((stream_format_code & 2) >> 1) | (chctx->bandFlagsBuf[i] << 1)];
|
|
if (chctx->codewords[j] >= middle_value)
|
|
chctx->CWdecoded[j] = quantizer[chctx->codewords[j] - 1] * chctx->flcoeffs6[i];
|
|
else
|
|
chctx->CWdecoded[j] = -quantizer[max_size - 2 - chctx->codewords[j]] * chctx->flcoeffs6[i];
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int imc_get_coeffs(IMCContext *q, IMCChannel *chctx)
|
|
{
|
|
int i, j, cw_len, cw;
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (!chctx->sumLenArr[i])
|
|
continue;
|
|
if (chctx->bandFlagsBuf[i] || chctx->bandWidthT[i]) {
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
|
|
cw_len = chctx->CWlengthT[j];
|
|
cw = 0;
|
|
|
|
if (get_bits_count(&q->gb) + cw_len > 512) {
|
|
av_dlog(NULL, "Band %i coeff %i cw_len %i\n", i, j, cw_len);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
if (cw_len && (!chctx->bandFlagsBuf[i] || !chctx->skipFlags[j]))
|
|
cw = get_bits(&q->gb, cw_len);
|
|
|
|
chctx->codewords[j] = cw;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int imc_decode_block(AVCodecContext *avctx, IMCContext *q, int ch)
|
|
{
|
|
int stream_format_code;
|
|
int imc_hdr, i, j, ret;
|
|
int flag;
|
|
int bits, summer;
|
|
int counter, bitscount;
|
|
IMCChannel *chctx = q->chctx + ch;
|
|
|
|
|
|
/* Check the frame header */
|
|
imc_hdr = get_bits(&q->gb, 9);
|
|
if (imc_hdr & 0x18) {
|
|
av_log(avctx, AV_LOG_ERROR, "frame header check failed!\n");
|
|
av_log(avctx, AV_LOG_ERROR, "got %X.\n", imc_hdr);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
stream_format_code = get_bits(&q->gb, 3);
|
|
|
|
if (stream_format_code & 1) {
|
|
avpriv_request_sample(avctx, "Stream format %X", stream_format_code);
|
|
return AVERROR_PATCHWELCOME;
|
|
}
|
|
|
|
if (stream_format_code & 0x04)
|
|
chctx->decoder_reset = 1;
|
|
|
|
if (chctx->decoder_reset) {
|
|
for (i = 0; i < BANDS; i++)
|
|
chctx->old_floor[i] = 1.0;
|
|
for (i = 0; i < COEFFS; i++)
|
|
chctx->CWdecoded[i] = 0;
|
|
chctx->decoder_reset = 0;
|
|
}
|
|
|
|
flag = get_bits1(&q->gb);
|
|
imc_read_level_coeffs(q, stream_format_code, chctx->levlCoeffBuf);
|
|
|
|
if (stream_format_code & 0x4)
|
|
imc_decode_level_coefficients(q, chctx->levlCoeffBuf,
|
|
chctx->flcoeffs1, chctx->flcoeffs2);
|
|
else
|
|
imc_decode_level_coefficients2(q, chctx->levlCoeffBuf, chctx->old_floor,
|
|
chctx->flcoeffs1, chctx->flcoeffs2);
|
|
|
|
memcpy(chctx->old_floor, chctx->flcoeffs1, 32 * sizeof(float));
|
|
|
|
counter = 0;
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (chctx->levlCoeffBuf[i] == 16) {
|
|
chctx->bandWidthT[i] = 0;
|
|
counter++;
|
|
} else
|
|
chctx->bandWidthT[i] = band_tab[i + 1] - band_tab[i];
|
|
}
|
|
memset(chctx->bandFlagsBuf, 0, BANDS * sizeof(int));
|
|
for (i = 0; i < BANDS - 1; i++) {
|
|
if (chctx->bandWidthT[i])
|
|
chctx->bandFlagsBuf[i] = get_bits1(&q->gb);
|
|
}
|
|
|
|
imc_calculate_coeffs(q, chctx->flcoeffs1, chctx->flcoeffs2, chctx->bandWidthT, chctx->flcoeffs3, chctx->flcoeffs5);
|
|
|
|
bitscount = 0;
|
|
/* first 4 bands will be assigned 5 bits per coefficient */
|
|
if (stream_format_code & 0x2) {
|
|
bitscount += 15;
|
|
|
|
chctx->bitsBandT[0] = 5;
|
|
chctx->CWlengthT[0] = 5;
|
|
chctx->CWlengthT[1] = 5;
|
|
chctx->CWlengthT[2] = 5;
|
|
for (i = 1; i < 4; i++) {
|
|
bits = (chctx->levlCoeffBuf[i] == 16) ? 0 : 5;
|
|
chctx->bitsBandT[i] = bits;
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
|
|
chctx->CWlengthT[j] = bits;
|
|
bitscount += bits;
|
|
}
|
|
}
|
|
}
|
|
if (avctx->codec_id == AV_CODEC_ID_IAC) {
|
|
bitscount += !!chctx->bandWidthT[BANDS - 1];
|
|
if (!(stream_format_code & 0x2))
|
|
bitscount += 16;
|
|
}
|
|
|
|
if ((ret = bit_allocation(q, chctx, stream_format_code,
|
|
512 - bitscount - get_bits_count(&q->gb),
|
|
flag)) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "Bit allocations failed\n");
|
|
chctx->decoder_reset = 1;
|
|
return ret;
|
|
}
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
chctx->sumLenArr[i] = 0;
|
|
chctx->skipFlagRaw[i] = 0;
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++)
|
|
chctx->sumLenArr[i] += chctx->CWlengthT[j];
|
|
if (chctx->bandFlagsBuf[i])
|
|
if ((((band_tab[i + 1] - band_tab[i]) * 1.5) > chctx->sumLenArr[i]) && (chctx->sumLenArr[i] > 0))
|
|
chctx->skipFlagRaw[i] = 1;
|
|
}
|
|
|
|
imc_get_skip_coeff(q, chctx);
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
chctx->flcoeffs6[i] = chctx->flcoeffs1[i];
|
|
/* band has flag set and at least one coded coefficient */
|
|
if (chctx->bandFlagsBuf[i] && (band_tab[i + 1] - band_tab[i]) != chctx->skipFlagCount[i]) {
|
|
chctx->flcoeffs6[i] *= q->sqrt_tab[ band_tab[i + 1] - band_tab[i]] /
|
|
q->sqrt_tab[(band_tab[i + 1] - band_tab[i] - chctx->skipFlagCount[i])];
|
|
}
|
|
}
|
|
|
|
/* calculate bits left, bits needed and adjust bit allocation */
|
|
bits = summer = 0;
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
if (chctx->bandFlagsBuf[i]) {
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++) {
|
|
if (chctx->skipFlags[j]) {
|
|
summer += chctx->CWlengthT[j];
|
|
chctx->CWlengthT[j] = 0;
|
|
}
|
|
}
|
|
bits += chctx->skipFlagBits[i];
|
|
summer -= chctx->skipFlagBits[i];
|
|
}
|
|
}
|
|
imc_adjust_bit_allocation(q, chctx, summer);
|
|
|
|
for (i = 0; i < BANDS; i++) {
|
|
chctx->sumLenArr[i] = 0;
|
|
|
|
for (j = band_tab[i]; j < band_tab[i + 1]; j++)
|
|
if (!chctx->skipFlags[j])
|
|
chctx->sumLenArr[i] += chctx->CWlengthT[j];
|
|
}
|
|
|
|
memset(chctx->codewords, 0, sizeof(chctx->codewords));
|
|
|
|
if (imc_get_coeffs(q, chctx) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "Read coefficients failed\n");
|
|
chctx->decoder_reset = 1;
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
if (inverse_quant_coeff(q, chctx, stream_format_code) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "Inverse quantization of coefficients failed\n");
|
|
chctx->decoder_reset = 1;
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
memset(chctx->skipFlags, 0, sizeof(chctx->skipFlags));
|
|
|
|
imc_imdct256(q, chctx, avctx->channels);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int imc_decode_frame(AVCodecContext *avctx, void *data,
|
|
int *got_frame_ptr, AVPacket *avpkt)
|
|
{
|
|
AVFrame *frame = data;
|
|
const uint8_t *buf = avpkt->data;
|
|
int buf_size = avpkt->size;
|
|
int ret, i;
|
|
|
|
IMCContext *q = avctx->priv_data;
|
|
|
|
LOCAL_ALIGNED_16(uint16_t, buf16, [IMC_BLOCK_SIZE / 2]);
|
|
|
|
if (buf_size < IMC_BLOCK_SIZE * avctx->channels) {
|
|
av_log(avctx, AV_LOG_ERROR, "frame too small!\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
/* get output buffer */
|
|
frame->nb_samples = COEFFS;
|
|
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
|
|
return ret;
|
|
}
|
|
|
|
for (i = 0; i < avctx->channels; i++) {
|
|
q->out_samples = (float *)frame->extended_data[i];
|
|
|
|
q->dsp.bswap16_buf(buf16, (const uint16_t*)buf, IMC_BLOCK_SIZE / 2);
|
|
|
|
init_get_bits(&q->gb, (const uint8_t*)buf16, IMC_BLOCK_SIZE * 8);
|
|
|
|
buf += IMC_BLOCK_SIZE;
|
|
|
|
if ((ret = imc_decode_block(avctx, q, i)) < 0)
|
|
return ret;
|
|
}
|
|
|
|
if (avctx->channels == 2) {
|
|
q->fdsp.butterflies_float((float *)frame->extended_data[0],
|
|
(float *)frame->extended_data[1], COEFFS);
|
|
}
|
|
|
|
*got_frame_ptr = 1;
|
|
|
|
return IMC_BLOCK_SIZE * avctx->channels;
|
|
}
|
|
|
|
|
|
static av_cold int imc_decode_close(AVCodecContext * avctx)
|
|
{
|
|
IMCContext *q = avctx->priv_data;
|
|
|
|
ff_fft_end(&q->fft);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
AVCodec ff_imc_decoder = {
|
|
.name = "imc",
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.id = AV_CODEC_ID_IMC,
|
|
.priv_data_size = sizeof(IMCContext),
|
|
.init = imc_decode_init,
|
|
.close = imc_decode_close,
|
|
.decode = imc_decode_frame,
|
|
.capabilities = CODEC_CAP_DR1,
|
|
.long_name = NULL_IF_CONFIG_SMALL("IMC (Intel Music Coder)"),
|
|
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
|
|
AV_SAMPLE_FMT_NONE },
|
|
};
|
|
|
|
AVCodec ff_iac_decoder = {
|
|
.name = "iac",
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.id = AV_CODEC_ID_IAC,
|
|
.priv_data_size = sizeof(IMCContext),
|
|
.init = imc_decode_init,
|
|
.close = imc_decode_close,
|
|
.decode = imc_decode_frame,
|
|
.capabilities = CODEC_CAP_DR1,
|
|
.long_name = NULL_IF_CONFIG_SMALL("IAC (Indeo Audio Coder)"),
|
|
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
|
|
AV_SAMPLE_FMT_NONE },
|
|
};
|