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Diffstat (limited to 'ffmpeg/libavcodec/imc.c')
| -rw-r--r-- | ffmpeg/libavcodec/imc.c | 1025 |
1 files changed, 1025 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/imc.c b/ffmpeg/libavcodec/imc.c new file mode 100644 index 0000000..eb7c255 --- /dev/null +++ b/ffmpeg/libavcodec/imc.c @@ -0,0 +1,1025 @@ +/* + * IMC compatible decoder + * Copyright (c) 2002-2004 Maxim Poliakovski + * Copyright (c) 2006 Benjamin Larsson + * Copyright (c) 2006 Konstantin Shishkov + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * IMC - Intel Music Coder + * A mdct based codec using a 256 points large transform + * divided into 32 bands with some mix of scale factors. + * Only mono is supported. + * + */ + + +#include <math.h> +#include <stddef.h> +#include <stdio.h> + +#include "libavutil/channel_layout.h" +#include "libavutil/float_dsp.h" +#include "libavutil/internal.h" +#include "libavutil/libm.h" +#include "avcodec.h" +#include "get_bits.h" +#include "dsputil.h" +#include "fft.h" +#include "internal.h" +#include "sinewin.h" + +#include "imcdata.h" + +#define IMC_BLOCK_SIZE 64 +#define IMC_FRAME_ID 0x21 +#define BANDS 32 +#define COEFFS 256 + +typedef struct IMCChannel { + float old_floor[BANDS]; + float flcoeffs1[BANDS]; + float flcoeffs2[BANDS]; + float flcoeffs3[BANDS]; + float flcoeffs4[BANDS]; + float flcoeffs5[BANDS]; + float flcoeffs6[BANDS]; + float CWdecoded[COEFFS]; + + int bandWidthT[BANDS]; ///< codewords per band + int bitsBandT[BANDS]; ///< how many bits per codeword in band + int CWlengthT[COEFFS]; ///< how many bits in each codeword + int levlCoeffBuf[BANDS]; + int bandFlagsBuf[BANDS]; ///< flags for each band + int sumLenArr[BANDS]; ///< bits for all coeffs in band + int skipFlagRaw[BANDS]; ///< skip flags are stored in raw form or not + int skipFlagBits[BANDS]; ///< bits used to code skip flags + int skipFlagCount[BANDS]; ///< skipped coeffients per band + int skipFlags[COEFFS]; ///< skip coefficient decoding or not + int codewords[COEFFS]; ///< raw codewords read from bitstream + + float last_fft_im[COEFFS]; + + int decoder_reset; +} IMCChannel; + +typedef struct { + IMCChannel chctx[2]; + + /** MDCT tables */ + //@{ + float mdct_sine_window[COEFFS]; + float post_cos[COEFFS]; + float post_sin[COEFFS]; + float pre_coef1[COEFFS]; + float pre_coef2[COEFFS]; + //@} + + float sqrt_tab[30]; + GetBitContext gb; + + DSPContext dsp; + AVFloatDSPContext fdsp; + FFTContext fft; + DECLARE_ALIGNED(32, FFTComplex, samples)[COEFFS / 2]; + float *out_samples; + + int8_t cyclTab[32], cyclTab2[32]; + float weights1[31], weights2[31]; +} IMCContext; + +static VLC huffman_vlc[4][4]; + +#define VLC_TABLES_SIZE 9512 + +static const int vlc_offsets[17] = { + 0, 640, 1156, 1732, 2308, 2852, 3396, 3924, + 4452, 5220, 5860, 6628, 7268, 7908, 8424, 8936, VLC_TABLES_SIZE +}; + +static VLC_TYPE vlc_tables[VLC_TABLES_SIZE][2]; + +static inline double freq2bark(double freq) +{ + return 3.5 * atan((freq / 7500.0) * (freq / 7500.0)) + 13.0 * atan(freq * 0.00076); +} + +static av_cold void iac_generate_tabs(IMCContext *q, int sampling_rate) +{ + double freqmin[32], freqmid[32], freqmax[32]; + double scale = sampling_rate / (256.0 * 2.0 * 2.0); + double nyquist_freq = sampling_rate * 0.5; + double freq, bark, prev_bark = 0, tf, tb; + int i, j; + + for (i = 0; i < 32; i++) { + freq = (band_tab[i] + band_tab[i + 1] - 1) * scale; + bark = freq2bark(freq); + + if (i > 0) { + tb = bark - prev_bark; + q->weights1[i - 1] = pow(10.0, -1.0 * tb); + q->weights2[i - 1] = pow(10.0, -2.7 * tb); + } + prev_bark = bark; + + freqmid[i] = freq; + + tf = freq; + while (tf < nyquist_freq) { + tf += 0.5; + tb = freq2bark(tf); + if (tb > bark + 0.5) + break; + } + freqmax[i] = tf; + + tf = freq; + while (tf > 0.0) { + tf -= 0.5; + tb = freq2bark(tf); + if (tb <= bark - 0.5) + break; + } + freqmin[i] = tf; + } + + for (i = 0; i < 32; i++) { + freq = freqmax[i]; + for (j = 31; j > 0 && freq <= freqmid[j]; j--); + q->cyclTab[i] = j + 1; + + freq = freqmin[i]; + for (j = 0; j < 32 && freq >= freqmid[j]; j++); + q->cyclTab2[i] = j - 1; + } +} + +static av_cold int imc_decode_init(AVCodecContext *avctx) +{ + int i, j, ret; + IMCContext *q = avctx->priv_data; + double r1, r2; + + if (avctx->codec_id == AV_CODEC_ID_IMC) + avctx->channels = 1; + + if (avctx->channels > 2) { + avpriv_request_sample(avctx, "Number of channels > 2"); + return AVERROR_PATCHWELCOME; + } + + for (j = 0; j < avctx->channels; j++) { + q->chctx[j].decoder_reset = 1; + + for (i = 0; i < BANDS; i++) + q->chctx[j].old_floor[i] = 1.0; + + for (i = 0; i < COEFFS / 2; i++) + q->chctx[j].last_fft_im[i] = 0; + } + + /* Build mdct window, a simple sine window normalized with sqrt(2) */ + ff_sine_window_init(q->mdct_sine_window, COEFFS); + for (i = 0; i < COEFFS; i++) + q->mdct_sine_window[i] *= sqrt(2.0); + for (i = 0; i < COEFFS / 2; i++) { + q->post_cos[i] = (1.0f / 32768) * cos(i / 256.0 * M_PI); + q->post_sin[i] = (1.0f / 32768) * sin(i / 256.0 * M_PI); + + r1 = sin((i * 4.0 + 1.0) / 1024.0 * M_PI); + r2 = cos((i * 4.0 + 1.0) / 1024.0 * M_PI); + + if (i & 0x1) { + q->pre_coef1[i] = (r1 + r2) * sqrt(2.0); + q->pre_coef2[i] = -(r1 - r2) * sqrt(2.0); + } else { + q->pre_coef1[i] = -(r1 + r2) * sqrt(2.0); + q->pre_coef2[i] = (r1 - r2) * sqrt(2.0); + } + } + + /* Generate a square root table */ + + for (i = 0; i < 30; i++) + q->sqrt_tab[i] = sqrt(i); + + /* initialize the VLC tables */ + for (i = 0; i < 4 ; i++) { + for (j = 0; j < 4; j++) { + huffman_vlc[i][j].table = &vlc_tables[vlc_offsets[i * 4 + j]]; + huffman_vlc[i][j].table_allocated = vlc_offsets[i * 4 + j + 1] - vlc_offsets[i * 4 + j]; + init_vlc(&huffman_vlc[i][j], 9, imc_huffman_sizes[i], + imc_huffman_lens[i][j], 1, 1, + imc_huffman_bits[i][j], 2, 2, INIT_VLC_USE_NEW_STATIC); + } + } + + if (avctx->codec_id == AV_CODEC_ID_IAC) { + iac_generate_tabs(q, avctx->sample_rate); + } else { + memcpy(q->cyclTab, cyclTab, sizeof(cyclTab)); + memcpy(q->cyclTab2, cyclTab2, sizeof(cyclTab2)); + memcpy(q->weights1, imc_weights1, sizeof(imc_weights1)); + memcpy(q->weights2, imc_weights2, sizeof(imc_weights2)); + } + + if ((ret = ff_fft_init(&q->fft, 7, 1))) { + av_log(avctx, AV_LOG_INFO, "FFT init failed\n"); + return ret; + } + ff_dsputil_init(&q->dsp, avctx); + avpriv_float_dsp_init(&q->fdsp, avctx->flags & CODEC_FLAG_BITEXACT); + avctx->sample_fmt = AV_SAMPLE_FMT_FLTP; + avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO + : AV_CH_LAYOUT_STEREO; + + return 0; +} + +static void imc_calculate_coeffs(IMCContext *q, float *flcoeffs1, + float *flcoeffs2, int *bandWidthT, + float *flcoeffs3, float *flcoeffs5) +{ + float workT1[BANDS]; + float workT2[BANDS]; + float workT3[BANDS]; + float snr_limit = 1.e-30; + float accum = 0.0; + int i, cnt2; + + for (i = 0; i < BANDS; i++) { + flcoeffs5[i] = workT2[i] = 0.0; + if (bandWidthT[i]) { + workT1[i] = flcoeffs1[i] * flcoeffs1[i]; + flcoeffs3[i] = 2.0 * flcoeffs2[i]; + } else { + workT1[i] = 0.0; + flcoeffs3[i] = -30000.0; + } + workT3[i] = bandWidthT[i] * workT1[i] * 0.01; + if (workT3[i] <= snr_limit) + workT3[i] = 0.0; + } + + for (i = 0; i < BANDS; i++) { + for (cnt2 = i; cnt2 < q->cyclTab[i]; cnt2++) + flcoeffs5[cnt2] = flcoeffs5[cnt2] + workT3[i]; + workT2[cnt2 - 1] = workT2[cnt2 - 1] + workT3[i]; + } + + for (i = 1; i < BANDS; i++) { + accum = (workT2[i - 1] + accum) * q->weights1[i - 1]; + flcoeffs5[i] += accum; + } + + for (i = 0; i < BANDS; i++) + workT2[i] = 0.0; + + for (i = 0; i < BANDS; i++) { + for (cnt2 = i - 1; cnt2 > q->cyclTab2[i]; cnt2--) + flcoeffs5[cnt2] += workT3[i]; + workT2[cnt2+1] += workT3[i]; + } + + accum = 0.0; + + for (i = BANDS-2; i >= 0; i--) { + accum = (workT2[i+1] + accum) * q->weights2[i]; + flcoeffs5[i] += accum; + // there is missing code here, but it seems to never be triggered + } +} + + +static void imc_read_level_coeffs(IMCContext *q, int stream_format_code, + int *levlCoeffs) +{ + int i; + VLC *hufftab[4]; + int start = 0; + const uint8_t *cb_sel; + int s; + + s = stream_format_code >> 1; + hufftab[0] = &huffman_vlc[s][0]; + hufftab[1] = &huffman_vlc[s][1]; + hufftab[2] = &huffman_vlc[s][2]; + hufftab[3] = &huffman_vlc[s][3]; + cb_sel = imc_cb_select[s]; + + if (stream_format_code & 4) + start = 1; + if (start) + levlCoeffs[0] = get_bits(&q->gb, 7); + for (i = start; i < BANDS; i++) { + levlCoeffs[i] = get_vlc2(&q->gb, hufftab[cb_sel[i]]->table, + hufftab[cb_sel[i]]->bits, 2); + if (levlCoeffs[i] == 17) + levlCoeffs[i] += get_bits(&q->gb, 4); + } +} + +static void imc_decode_level_coefficients(IMCContext *q, int *levlCoeffBuf, + float *flcoeffs1, float *flcoeffs2) +{ + int i, level; + float tmp, tmp2; + // maybe some frequency division thingy + + flcoeffs1[0] = 20000.0 / exp2 (levlCoeffBuf[0] * 0.18945); // 0.18945 = log2(10) * 0.05703125 + flcoeffs2[0] = log2f(flcoeffs1[0]); + tmp = flcoeffs1[0]; + tmp2 = flcoeffs2[0]; + + for (i = 1; i < BANDS; i++) { + level = levlCoeffBuf[i]; + if (level == 16) { + flcoeffs1[i] = 1.0; + flcoeffs2[i] = 0.0; + } else { + if (level < 17) + level -= 7; + else if (level <= 24) + level -= 32; + else + level -= 16; + + tmp *= imc_exp_tab[15 + level]; + tmp2 += 0.83048 * level; // 0.83048 = log2(10) * 0.25 + flcoeffs1[i] = tmp; + flcoeffs2[i] = tmp2; + } + } +} + + +static void imc_decode_level_coefficients2(IMCContext *q, int *levlCoeffBuf, + float *old_floor, float *flcoeffs1, + float *flcoeffs2) +{ + int i; + /* FIXME maybe flag_buf = noise coding and flcoeffs1 = new scale factors + * and flcoeffs2 old scale factors + * might be incomplete due to a missing table that is in the binary code + */ + for (i = 0; i < BANDS; i++) { + flcoeffs1[i] = 0; + if (levlCoeffBuf[i] < 16) { + flcoeffs1[i] = imc_exp_tab2[levlCoeffBuf[i]] * old_floor[i]; + flcoeffs2[i] = (levlCoeffBuf[i] - 7) * 0.83048 + flcoeffs2[i]; // 0.83048 = log2(10) * 0.25 + } else { + flcoeffs1[i] = old_floor[i]; + } + } +} + +/** + * Perform bit allocation depending on bits available + */ +static int bit_allocation(IMCContext *q, IMCChannel *chctx, + int stream_format_code, int freebits, int flag) +{ + int i, j; + const float limit = -1.e20; + float highest = 0.0; + int indx; + int t1 = 0; + int t2 = 1; + float summa = 0.0; + int iacc = 0; + int summer = 0; + int rres, cwlen; + float lowest = 1.e10; + int low_indx = 0; + float workT[32]; + int flg; + int found_indx = 0; + + for (i = 0; i < BANDS; i++) + highest = FFMAX(highest, chctx->flcoeffs1[i]); + + for (i = 0; i < BANDS - 1; i++) + chctx->flcoeffs4[i] = chctx->flcoeffs3[i] - log2f(chctx->flcoeffs5[i]); + chctx->flcoeffs4[BANDS - 1] = limit; + + highest = highest * 0.25; + + for (i = 0; i < BANDS; i++) { + indx = -1; + if ((band_tab[i + 1] - band_tab[i]) == chctx->bandWidthT[i]) + indx = 0; + + if ((band_tab[i + 1] - band_tab[i]) > chctx->bandWidthT[i]) + indx = 1; + + if (((band_tab[i + 1] - band_tab[i]) / 2) >= chctx->bandWidthT[i]) + indx = 2; + + if (indx == -1) + return AVERROR_INVALIDDATA; + + chctx->flcoeffs4[i] += xTab[(indx * 2 + (chctx->flcoeffs1[i] < highest)) * 2 + flag]; + } + + if (stream_format_code & 0x2) { + chctx->flcoeffs4[0] = limit; + chctx->flcoeffs4[1] = limit; + chctx->flcoeffs4[2] = limit; + chctx->flcoeffs4[3] = limit; + } + + for (i = (stream_format_code & 0x2) ? 4 : 0; i < BANDS - 1; i++) { + iacc += chctx->bandWidthT[i]; + summa += chctx->bandWidthT[i] * chctx->flcoeffs4[i]; + } + chctx->bandWidthT[BANDS - 1] = 0; + summa = (summa * 0.5 - freebits) / iacc; + + + for (i = 0; i < BANDS / 2; i++) { + rres = summer - freebits; + if ((rres >= -8) && (rres <= 8)) + 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); + + for(i=0; i<BANDS; i++) { + if(chctx->flcoeffs1[i] > INT_MAX) { + av_log(avctx, AV_LOG_ERROR, "scalefactor out of range\n"); + return AVERROR_INVALIDDATA; + } + } + + 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) + 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; +} + +static av_cold void flush(AVCodecContext *avctx) +{ + IMCContext *q = avctx->priv_data; + + q->chctx[0].decoder_reset = + q->chctx[1].decoder_reset = 1; +} + +#if CONFIG_IMC_DECODER +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, + .flush = flush, + .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 }, +}; +#endif +#if CONFIG_IAC_DECODER +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, + .flush = flush, + .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 }, +}; +#endif |