From 84ed36da85b65b3b135f4dc06589454190fd4572 Mon Sep 17 00:00:00 2001 From: Kostya Shishkov Date: Mon, 30 Oct 2006 13:48:48 +0000 Subject: IMC decoder Originally committed as revision 6839 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/imc.c | 816 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 816 insertions(+) create mode 100644 libavcodec/imc.c (limited to 'libavcodec/imc.c') diff --git a/libavcodec/imc.c b/libavcodec/imc.c new file mode 100644 index 0000000000..a7045ef3e1 --- /dev/null +++ b/libavcodec/imc.c @@ -0,0 +1,816 @@ +/* + * 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.c IMC - Intel Music Coder + * A mdct based codec using a 256 points large transform + * divied into 32 bands with some mix of scale factors. + * Only mono is supported. + * + */ + + +#include +#include +#include + +#define ALT_BITSTREAM_READER +#include "avcodec.h" +#include "bitstream.h" +#include "dsputil.h" + +#include "imcdata.h" + +#define IMC_FRAME_ID 0x21 +#define BANDS 32 +#define COEFFS 256 + +typedef struct { + 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]; + + /** MDCT tables */ + //@{ + float mdct_sine_window[COEFFS]; + float post_cos[COEFFS]; + float post_sin[COEFFS]; + float pre_coef1[COEFFS]; + float pre_coef2[COEFFS]; + float last_fft_im[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 sqrt_tab[30]; + GetBitContext gb; + VLC huffman_vlc[4][4]; + float flcf1, flcf2; + int decoder_reset; + float one_div_log2; + + DSPContext dsp; + FFTContext fft; + DECLARE_ALIGNED_16(FFTComplex, samples[COEFFS/2]); + DECLARE_ALIGNED_16(float, out_samples[COEFFS]); +} IMCContext; + + +static int imc_decode_init(AVCodecContext * avctx) +{ + int i, j; + IMCContext *q = avctx->priv_data; + double r1, r2; + + q->decoder_reset = 1; + + for(i = 0; i < BANDS; i++) + q->old_floor[i] = 1.0; + + /* Build mdct window, a simple sine window normalized with sqrt(2) */ + for(i = 0; i < COEFFS; i++) + q->mdct_sine_window[i] = sin((i + 0.5) / 512.0 * M_PI) * sqrt(2.0); + for(i = 0; i < COEFFS/2; i++){ + q->post_cos[i] = cos(i / 256.0 * M_PI); + q->post_sin[i] = 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); + } + + q->last_fft_im[i] = 0; + } + q->flcf1 = log2(10) * 0.05703125; + q->flcf2 = log2(10) * 0.25; + + /* 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++) { + init_vlc (&q->huffman_vlc[i][j], 9, imc_huffman_sizes[i], + imc_huffman_lens[i][j], 1, 1, + imc_huffman_bits[i][j], 2, 2, 0); + } + } + q->one_div_log2 = 1/log(2); + + ff_fft_init(&q->fft, 7, 1); + dsputil_init(&q->dsp, avctx); + 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 < 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) * imc_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 > 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) * imc_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] = &q->huffman_vlc[s][0]; + hufftab[1] = &q->huffman_vlc[s][1]; + hufftab[2] = &q->huffman_vlc[s][2]; + hufftab[3] = &q->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 / pow (2, levlCoeffBuf[0] * q->flcf1); + flcoeffs2[0] = log2(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 += q->flcf2 * level; + 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) * q->flcf2 + flcoeffs2[i]; + } else { + flcoeffs1[i] = old_floor[i]; + } + } +} + +/** + * Perform bit allocation depending on bits available + */ +static int bit_allocation (IMCContext* q, 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, q->flcoeffs1[i]); + + for(i = 0; i < BANDS-1; i++) { + q->flcoeffs4[i] = q->flcoeffs3[i] - log2(q->flcoeffs5[i]); + } + q->flcoeffs4[BANDS - 1] = limit; + + highest = highest * 0.25; + + for(i = 0; i < BANDS; i++) { + indx = -1; + if ((band_tab[i+1] - band_tab[i]) == q->bandWidthT[i]) + indx = 0; + + if ((band_tab[i+1] - band_tab[i]) > q->bandWidthT[i]) + indx = 1; + + if (((band_tab[i+1] - band_tab[i])/2) >= q->bandWidthT[i]) + indx = 2; + + if (indx == -1) + return -1; + + q->flcoeffs4[i] = q->flcoeffs4[i] + xTab[(indx*2 + (q->flcoeffs1[i] < highest)) * 2 + flag]; + } + + if (stream_format_code & 0x2) { + q->flcoeffs4[0] = limit; + q->flcoeffs4[1] = limit; + q->flcoeffs4[2] = limit; + q->flcoeffs4[3] = limit; + } + + for(i = (stream_format_code & 0x2)?4:0; i < BANDS-1; i++) { + iacc += q->bandWidthT[i]; + summa += q->bandWidthT[i] * q->flcoeffs4[i]; + } + q->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 = clip((int)((q->flcoeffs4[j] * 0.5) - summa + 0.5), 0, 6); + + q->bitsBandT[j] = cwlen; + summer += q->bandWidthT[j] * cwlen; + + if (cwlen > 0) + iacc += q->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++) + q->CWlengthT[j] = q->bitsBandT[i]; + } + + if (freebits > summer) { + for(i = 0; i < BANDS; i++) { + workT[i] = (q->bitsBandT[i] == 6) ? -1.e20 : (q->bitsBandT[i] * -2 + q->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 (++(q->bitsBandT[found_indx]) == 6) + workT[found_indx] = -1.e20; + + for(j = band_tab[found_indx]; j < band_tab[found_indx+1] && (freebits > summer); j++){ + q->CWlengthT[j]++; + summer++; + } + } + }while (freebits > summer); + } + if (freebits < summer) { + for(i = 0; i < BANDS; i++) { + workT[i] = q->bitsBandT[i] ? (q->bitsBandT[i] * -2 + q->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 (!(--q->bitsBandT[low_indx])) + workT[low_indx] = 1.e20; + + for(j = band_tab[low_indx]; j < band_tab[low_indx+1] && (freebits < summer); j++){ + if(q->CWlengthT[j] > 0){ + q->CWlengthT[j]--; + summer--; + } + } + } + } + return 0; +} + +static void imc_get_skip_coeff(IMCContext* q) { + int i, j; + + memset(q->skipFlagBits, 0, sizeof(q->skipFlagBits)); + memset(q->skipFlagCount, 0, sizeof(q->skipFlagCount)); + for(i = 0; i < BANDS; i++) { + if (!q->bandFlagsBuf[i] || !q->bandWidthT[i]) + continue; + + if (!q->skipFlagRaw[i]) { + q->skipFlagBits[i] = band_tab[i+1] - band_tab[i]; + + for(j = band_tab[i]; j < band_tab[i+1]; j++) { + if ((q->skipFlags[j] = get_bits(&q->gb,1))) + q->skipFlagCount[i]++; + } + } else { + for(j = band_tab[i]; j < (band_tab[i+1]-1); j += 2) { + if(!get_bits1(&q->gb)){//0 + q->skipFlagBits[i]++; + q->skipFlags[j]=1; + q->skipFlags[j+1]=1; + q->skipFlagCount[i] += 2; + }else{ + if(get_bits1(&q->gb)){//11 + q->skipFlagBits[i] +=2; + q->skipFlags[j]=0; + q->skipFlags[j+1]=1; + q->skipFlagCount[i]++; + }else{ + q->skipFlagBits[i] +=3; + q->skipFlags[j+1]=0; + if(!get_bits1(&q->gb)){//100 + q->skipFlags[j]=1; + q->skipFlagCount[i]++; + }else{//101 + q->skipFlags[j]=0; + } + } + } + } + + if (j < band_tab[i+1]) { + q->skipFlagBits[i]++; + if ((q->skipFlags[j] = get_bits(&q->gb,1))) + q->skipFlagCount[i]++; + } + } + } +} + +/** + * Increase highest' band coefficient sizes as some bits won't be used + */ +static void imc_adjust_bit_allocation (IMCContext* q, 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] = (q->bitsBandT[i] == 6) ? -1.e20 : (q->bitsBandT[i] * -2 + q->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 (++(q->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 (!q->skipFlags[j] && (q->CWlengthT[j] < 6)) { + q->CWlengthT[j]++; + corrected++; + } + } + } + } +} + +void imc_imdct256(IMCContext *q) { + int i; + float re, im; + + /* prerotation */ + for(i=0; i < COEFFS/2; i++){ + q->samples[i].re = -(q->pre_coef1[i] * q->CWdecoded[COEFFS-1-i*2]) - + (q->pre_coef2[i] * q->CWdecoded[i*2]); + q->samples[i].im = (q->pre_coef2[i] * q->CWdecoded[COEFFS-1-i*2]) - + (q->pre_coef1[i] * q->CWdecoded[i*2]); + } + + /* FFT */ + ff_fft_permute(&q->fft, q->samples); + ff_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]); + q->out_samples[i*2] = (q->mdct_sine_window[COEFFS-1-i*2] * q->last_fft_im[i]) + (q->mdct_sine_window[i*2] * re); + q->out_samples[COEFFS-1-i*2] = (q->mdct_sine_window[i*2] * q->last_fft_im[i]) - (q->mdct_sine_window[COEFFS-1-i*2] * re); + q->last_fft_im[i] = im; + } +} + +static int inverse_quant_coeff (IMCContext* q, 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++) { + q->CWdecoded[j] = 0; + cw_len = q->CWlengthT[j]; + + if (cw_len <= 0 || q->skipFlags[j]) + continue; + + max_size = 1 << cw_len; + middle_value = max_size >> 1; + + if (q->codewords[j] >= max_size || q->codewords[j] < 0) + return -1; + + if (cw_len >= 4){ + quantizer = imc_quantizer2[(stream_format_code & 2) >> 1]; + if (q->codewords[j] >= middle_value) + q->CWdecoded[j] = quantizer[q->codewords[j] - 8] * q->flcoeffs6[i]; + else + q->CWdecoded[j] = -quantizer[max_size - q->codewords[j] - 8 - 1] * q->flcoeffs6[i]; + }else{ + quantizer = imc_quantizer1[((stream_format_code & 2) >> 1) | (q->bandFlagsBuf[i] << 1)]; + if (q->codewords[j] >= middle_value) + q->CWdecoded[j] = quantizer[q->codewords[j] - 1] * q->flcoeffs6[i]; + else + q->CWdecoded[j] = -quantizer[max_size - 2 - q->codewords[j]] * q->flcoeffs6[i]; + } + } + } + return 0; +} + + +static int imc_get_coeffs (IMCContext* q) { + int i, j, cw_len, cw; + + for(i = 0; i < BANDS; i++) { + if(!q->sumLenArr[i]) continue; + if (q->bandFlagsBuf[i] || q->bandWidthT[i]) { + for(j = band_tab[i]; j < band_tab[i+1]; j++) { + cw_len = q->CWlengthT[j]; + cw = 0; + + if (get_bits_count(&q->gb) + cw_len > 512){ +//av_log(NULL,0,"Band %i coeff %i cw_len %i\n",i,j,cw_len); + return -1; + } + + if(cw_len && (!q->bandFlagsBuf[i] || !q->skipFlags[j])) + cw = get_bits(&q->gb, cw_len); + + q->codewords[j] = cw; + } + } + } + return 0; +} + +static int imc_decode_frame(AVCodecContext * avctx, + void *data, int *data_size, + uint8_t * buf, int buf_size) +{ + + IMCContext *q = avctx->priv_data; + + int stream_format_code; + int imc_hdr, i, j; + int flag; + int bits, summer; + int counter, bitscount; + uint16_t *buf16 = (uint16_t *) buf; + + /* FIXME: input should not be modified */ + for(i = 0; i < FFMIN(buf_size, avctx->block_align) / 2; i++) + buf16[i] = bswap_16(buf16[i]); + + init_get_bits(&q->gb, buf, 512); + + /* Check the frame header */ + imc_hdr = get_bits(&q->gb, 9); + if (imc_hdr != IMC_FRAME_ID) { + av_log(avctx, AV_LOG_ERROR, "imc frame header check failed!\n"); + av_log(avctx, AV_LOG_ERROR, "got %x instead of 0x21.\n", imc_hdr); + return -1; + } + stream_format_code = get_bits(&q->gb, 3); + + if(stream_format_code & 1){ + av_log(avctx, AV_LOG_ERROR, "Stream code format %X is not supported\n", stream_format_code); + return -1; + } + +// av_log(avctx, AV_LOG_DEBUG, "stream_format_code = %d\n", stream_format_code); + + if (stream_format_code & 0x04) + q->decoder_reset = 1; + + if(q->decoder_reset) { + memset(q->out_samples, 0, sizeof(q->out_samples)); + for(i = 0; i < BANDS; i++)q->old_floor[i] = 1.0; + for(i = 0; i < COEFFS; i++)q->CWdecoded[i] = 0; + q->decoder_reset = 0; + } + + flag = get_bits1(&q->gb); + imc_read_level_coeffs(q, stream_format_code, q->levlCoeffBuf); + + if (stream_format_code & 0x4) + imc_decode_level_coefficients(q, q->levlCoeffBuf, q->flcoeffs1, q->flcoeffs2); + else + imc_decode_level_coefficients2(q, q->levlCoeffBuf, q->old_floor, q->flcoeffs1, q->flcoeffs2); + + memcpy(q->old_floor, q->flcoeffs1, 32 * sizeof(float)); + + counter = 0; + for (i=0 ; ilevlCoeffBuf[i] == 16) { + q->bandWidthT[i] = 0; + counter++; + } else + q->bandWidthT[i] = band_tab[i+1] - band_tab[i]; + } + memset(q->bandFlagsBuf, 0, BANDS * sizeof(int)); + for(i = 0; i < BANDS-1; i++) { + if (q->bandWidthT[i]) + q->bandFlagsBuf[i] = get_bits1(&q->gb); + } + + imc_calculate_coeffs(q, q->flcoeffs1, q->flcoeffs2, q->bandWidthT, q->flcoeffs3, q->flcoeffs5); + + bitscount = 0; + /* first 4 bands will be assigned 5 bits per coefficient */ + if (stream_format_code & 0x2) { + bitscount += 15; + + q->bitsBandT[0] = 5; + q->CWlengthT[0] = 5; + q->CWlengthT[1] = 5; + q->CWlengthT[2] = 5; + for(i = 1; i < 4; i++){ + bits = (q->levlCoeffBuf[i] == 16) ? 0 : 5; + q->bitsBandT[i] = bits; + for(j = band_tab[i]; j < band_tab[i+1]; j++) { + q->CWlengthT[j] = bits; + bitscount += bits; + } + } + } + + if(bit_allocation (q, stream_format_code, 512 - bitscount - get_bits_count(&q->gb), flag) < 0) { + av_log(avctx, AV_LOG_ERROR, "Bit allocations failed\n"); + q->decoder_reset = 1; + return -1; + } + + for(i = 0; i < BANDS; i++) { + q->sumLenArr[i] = 0; + q->skipFlagRaw[i] = 0; + for(j = band_tab[i]; j < band_tab[i+1]; j++) + q->sumLenArr[i] += q->CWlengthT[j]; + if (q->bandFlagsBuf[i]) + if( (((band_tab[i+1] - band_tab[i]) * 1.5) > q->sumLenArr[i]) && (q->sumLenArr[i] > 0)) + q->skipFlagRaw[i] = 1; + } + + imc_get_skip_coeff(q); + + for(i = 0; i < BANDS; i++) { + q->flcoeffs6[i] = q->flcoeffs1[i]; + /* band has flag set and at least one coded coefficient */ + if (q->bandFlagsBuf[i] && (band_tab[i+1] - band_tab[i]) != q->skipFlagCount[i]){ + q->flcoeffs6[i] *= q->sqrt_tab[band_tab[i+1] - band_tab[i]] / + q->sqrt_tab[(band_tab[i+1] - band_tab[i] - q->skipFlagCount[i])]; + } + } + + /* calculate bits left, bits needed and adjust bit allocation */ + bits = summer = 0; + + for(i = 0; i < BANDS; i++) { + if (q->bandFlagsBuf[i]) { + for(j = band_tab[i]; j < band_tab[i+1]; j++) { + if(q->skipFlags[j]) { + summer += q->CWlengthT[j]; + q->CWlengthT[j] = 0; + } + } + bits += q->skipFlagBits[i]; + summer -= q->skipFlagBits[i]; + } + } + imc_adjust_bit_allocation(q, summer); + + for(i = 0; i < BANDS; i++) { + q->sumLenArr[i] = 0; + + for(j = band_tab[i]; j < band_tab[i+1]; j++) + if (!q->skipFlags[j]) + q->sumLenArr[i] += q->CWlengthT[j]; + } + + memset(q->codewords, 0, sizeof(q->codewords)); + + if(imc_get_coeffs(q) < 0) { + av_log(avctx, AV_LOG_ERROR, "Read coefficients failed\n"); + q->decoder_reset = 1; + return 0; + } + + if(inverse_quant_coeff(q, stream_format_code) < 0) { + av_log(avctx, AV_LOG_ERROR, "Inverse quantization of coefficients failed\n"); + q->decoder_reset = 1; + return 0; + } + + memset(q->skipFlags, 0, sizeof(q->skipFlags)); + + imc_imdct256(q); + + q->dsp.float_to_int16(data, q->out_samples, COEFFS); + + *data_size = COEFFS * sizeof(int16_t); + + return avctx->block_align; +} + + +static int imc_decode_close(AVCodecContext * avctx) +{ + IMCContext *q = avctx->priv_data; + + ff_fft_end(&q->fft); + return 0; +} + + +AVCodec imc_decoder = { + .name = "imc", + .type = CODEC_TYPE_AUDIO, + .id = CODEC_ID_IMC, + .priv_data_size = sizeof(IMCContext), + .init = imc_decode_init, + .close = imc_decode_close, + .decode = imc_decode_frame, +}; -- cgit v1.2.3