From dbb0f96f0ff776f6ccbdc11a6c285142850df831 Mon Sep 17 00:00:00 2001 From: Benjamin Larsson Date: Thu, 10 Sep 2009 18:47:02 +0000 Subject: [PATCH] Initial commit of the atrac1 decoder, not hooked up yet Originally committed as revision 19811 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/atrac1.c | 402 ++++++++++++++++++++++++++++++++++++++++ libavcodec/atrac1data.h | 62 +++++++ 2 files changed, 464 insertions(+) create mode 100644 libavcodec/atrac1.c create mode 100644 libavcodec/atrac1data.h diff --git a/libavcodec/atrac1.c b/libavcodec/atrac1.c new file mode 100644 index 0000000000..6d6abe6a4f --- /dev/null +++ b/libavcodec/atrac1.c @@ -0,0 +1,402 @@ +/* + * Atrac 1 compatible decoder + * Copyright (c) 2009 Maxim Poliakovski + * Copyright (c) 2009 Benjamin Larsson + * + * 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 libavcodec/atrac1.c + * Atrac 1 compatible decoder. + * This decoder handles raw ATRAC1 data. + */ + +/* Many thanks to Tim Craig for all the help! */ + +#include +#include +#include + +#include "avcodec.h" +#include "get_bits.h" +#include "dsputil.h" + +#include "atrac.h" +#include "atrac1data.h" + +#define AT1_MAX_BFU 52 ///< max number of block floating units in a sound unit +#define AT1_SU_SIZE 212 ///< number of bytes in a sound unit +#define AT1_SU_SAMPLES 512 ///< number of samples in a sound unit +#define AT1_FRAME_SIZE AT1_SU_SIZE * 2 +#define AT1_SU_MAX_BITS AT1_SU_SIZE * 8 +#define AT1_MAX_CHANNELS 2 + +#define AT1_QMF_BANDS 3 +#define IDX_LOW_BAND 0 +#define IDX_MID_BAND 1 +#define IDX_HIGH_BAND 2 + +/** + * Sound unit struct, one unit is used per channel + */ +typedef struct { + int log2_block_count[AT1_QMF_BANDS]; ///< log2 number of blocks in a band + int num_bfus; ///< number of Block Floating Units + int idwls[AT1_MAX_BFU]; ///< the word length indexes for each BFU + int idsfs[AT1_MAX_BFU]; ///< the scalefactor indexes for each BFU + float* spectrum[2]; + DECLARE_ALIGNED_16(float,spec1[AT1_SU_SAMPLES]); ///< mdct buffer + DECLARE_ALIGNED_16(float,spec2[AT1_SU_SAMPLES]); ///< mdct buffer + DECLARE_ALIGNED_16(float,fst_qmf_delay[46]); ///< delay line for the 1st stacked QMF filter + DECLARE_ALIGNED_16(float,snd_qmf_delay[46]); ///< delay line for the 2nd stacked QMF filter + DECLARE_ALIGNED_16(float,last_qmf_delay[256+23]); ///< delay line for the last stacked QMF filter +} AT1SUCtx; + +/** + * The atrac1 context, holds all needed parameters for decoding + */ +typedef struct { + AT1SUCtx SUs[AT1_MAX_CHANNELS]; ///< channel sound unit + DECLARE_ALIGNED_16(float,spec[AT1_SU_SAMPLES]); ///< the mdct spectrum buffer + DECLARE_ALIGNED_16(float,short_buf[64]); ///< buffer for the short mode + DECLARE_ALIGNED_16(float, low[256]); + DECLARE_ALIGNED_16(float, mid[256]); + DECLARE_ALIGNED_16(float,high[512]); + float* bands[3]; + float out_samples[AT1_MAX_CHANNELS][AT1_SU_SAMPLES]; + MDCTContext mdct_ctx[3]; + int channels; + DSPContext dsp; +} AT1Ctx; + +static float *short_window; +static float *mid_window; +DECLARE_ALIGNED_16(static float, long_window[256]); +static float *window_per_band[3]; + +/** size of the transform in samples in the long mode for each QMF band */ +static const uint16_t samples_per_band[3] = {128, 128, 256}; +static const uint8_t mdct_long_nbits[3] = {7, 7, 8}; + + +static void at1_imdct(AT1Ctx *q, float *spec, float *out, int nbits, int rev_spec) +{ + MDCTContext* mdct_context; + int transf_size = 1 << nbits; + + mdct_context = &q->mdct_ctx[nbits - 5 - (nbits>6)]; + + if (rev_spec) { + int i; + for (i=0 ; ilog2_block_count[band_num]; + + /* number of mdct blocks in the current QMF band: 1 - for long mode */ + /* 4 for short mode(low/middle bands) and 8 for short mode(high band)*/ + num_blocks = 1 << log2_block_count; + + /* mdct block size in samples: 128 (long mode, low & mid bands), */ + /* 256 (long mode, high band) and 32 (short mode, all bands) */ + block_size = band_samples >> log2_block_count; + + /* calc transform size in bits according to the block_size_mode */ + nbits = mdct_long_nbits[band_num] - log2_block_count; + + if (nbits!=5 && nbits!=7 && nbits!=8) + return -1; + + if (num_blocks == 1) { + at1_imdct(q, &q->spec[pos], &su->spectrum[0][ref_pos], nbits, band_num); + pos += block_size; // move to the next mdct block in the spectrum + } else { + /* calc start position for the 1st short block: 96(128) or 112(256) */ + start_pos = (band_samples * (num_blocks - 1)) >> (log2_block_count + 1); + memset(&su->spectrum[0][ref_pos], 0, sizeof(float) * (band_samples * 2)); + + for (; num_blocks!=0 ; num_blocks--) { + /* use hardcoded nbits for the short mode */ + at1_imdct(q, &q->spec[pos], q->short_buf, 5, band_num); + + /* overlap and window between short blocks */ + q->dsp.vector_fmul_window(&su->spectrum[0][ref_pos+start_pos], + &su->spectrum[0][ref_pos+start_pos],q->short_buf,short_window, 0, 16); + start_pos += 32; // use hardcoded block_size + pos += 32; + } + } + + /* overlap and window with the previous frame and output the result */ + q->dsp.vector_fmul_window(q->bands[band_num], &su->spectrum[1][ref_pos+band_samples/2], + &su->spectrum[0][ref_pos], window_per_band[band_num], 0, band_samples/2); + + ref_pos += band_samples; + } + + /* Swap buffers so the mdct overlap works */ + FFSWAP(float*, su->spectrum[0], su->spectrum[1]); + + return 0; +} + + +static int at1_parse_block_size_mode(GetBitContext* gb, int log2_block_count[AT1_QMF_BANDS]) +{ + int log2_block_count_tmp, i; + + for(i=0 ; i<2 ; i++) { + /* low and mid band */ + log2_block_count_tmp = get_bits(gb, 2); + if (log2_block_count_tmp & 1) + return -1; + log2_block_count[i] = 2 - log2_block_count_tmp; + } + + /* high band */ + log2_block_count_tmp = get_bits(gb, 2); + if (log2_block_count_tmp != 0 && log2_block_count_tmp != 3) + return -1; + log2_block_count[IDX_HIGH_BAND] = 3 - log2_block_count_tmp; + + skip_bits(gb, 2); + return 0; +} + + +static int at1_unpack_dequant(GetBitContext* gb, AT1SUCtx* su, float spec[AT1_SU_SAMPLES]) +{ + int bits_used, band_num, bfu_num, i; + + /* parse the info byte (2nd byte) telling how much BFUs were coded */ + su->num_bfus = bfu_amount_tab1[get_bits(gb, 3)]; + + /* calc number of consumed bits: + num_BFUs * (idwl(4bits) + idsf(6bits)) + log2_block_count(8bits) + info_byte(8bits) + + info_byte_copy(8bits) + log2_block_count_copy(8bits) */ + bits_used = su->num_bfus * 10 + 32 + + bfu_amount_tab2[get_bits(gb, 2)] + + (bfu_amount_tab3[get_bits(gb, 3)] << 1); + + /* get word length index (idwl) for each BFU */ + for (i=0 ; inum_bfus ; i++) + su->idwls[i] = get_bits(gb, 4); + + /* get scalefactor index (idsf) for each BFU */ + for (i=0 ; inum_bfus ; i++) + su->idsfs[i] = get_bits(gb, 6); + + /* zero idwl/idsf for empty BFUs */ + for (i = su->num_bfus; i < AT1_MAX_BFU; i++) + su->idwls[i] = su->idsfs[i] = 0; + + /* read in the spectral data and reconstruct MDCT spectrum of this channel */ + for (band_num=0 ; band_numidwls[bfu_num] + su->idwls[bfu_num]; + float scale_factor = sf_table[su->idsfs[bfu_num]]; + bits_used += word_len * num_specs; /* add number of bits consumed by current BFU */ + + /* check for bitstream overflow */ + if (bits_used > AT1_SU_MAX_BITS) + return -1; + + /* get the position of the 1st spec according to the block size mode */ + pos = su->log2_block_count[band_num] ? bfu_start_short[bfu_num] : bfu_start_long[bfu_num]; + + if (word_len) { + float max_quant = 1.0/(float)((1 << (word_len - 1)) - 1); + + for (i=0 ; i empty BFU, zero all specs in the emty BFU */ + memset(&spec[pos], 0, num_specs*sizeof(float)); + } + } + } + + return 0; +} + + +void at1_subband_synthesis(AT1Ctx *q, AT1SUCtx* su, float *pOut) +{ + float temp[256]; + float iqmf_temp[512 + 46]; + + /* combine low and middle bands */ + atrac_iqmf(q->bands[0], q->bands[1], 128, temp, su->fst_qmf_delay, iqmf_temp); + + /* delay the signal of the high band by 23 samples */ + memcpy( su->last_qmf_delay, &su->last_qmf_delay[256], sizeof(float)*23); + memcpy(&su->last_qmf_delay[23], q->bands[2], sizeof(float)*256); + + /* combine (low + middle) and high bands */ + atrac_iqmf(temp, su->last_qmf_delay, 256, pOut, su->snd_qmf_delay, iqmf_temp); +} + + +static int atrac1_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + int buf_size = avpkt->size; + AT1Ctx *q = avctx->priv_data; + int ch, ret, i; + GetBitContext gb; + float* samples = data; + + + if (buf_size < 212 * q->channels) { + av_log(q,AV_LOG_ERROR,"Not enought data to decode!\n"); + return -1; + } + + for (ch=0 ; chchannels ; ch++) { + AT1SUCtx* su = &q->SUs[ch]; + + init_get_bits(&gb, &buf[212*ch], 212*8); + + /* parse block_size_mode, 1st byte */ + ret = at1_parse_block_size_mode(&gb, su->log2_block_count); + if (ret < 0) + return ret; + + ret = at1_unpack_dequant(&gb, su, q->spec); + if (ret < 0) + return ret; + + ret = at1_imdct_block(su, q); + if (ret < 0) + return ret; + at1_subband_synthesis(q, su, q->out_samples[ch]); + } + + /* round, convert to 16bit and interleave */ + if (q->channels == 1) { + /* mono */ + q->dsp.vector_clipf(samples, q->out_samples[0], -32700./(1<<15), 32700./(1<<15), AT1_SU_SAMPLES); + } else { + /* stereo */ + for (i = 0; i < AT1_SU_SAMPLES; i++) { + samples[i*2] = av_clipf(q->out_samples[0][i], -32700./(1<<15), 32700./(1<<15)); + samples[i*2+1] = av_clipf(q->out_samples[1][i], -32700./(1<<15), 32700./(1<<15)); + } + } + + *data_size = q->channels * AT1_SU_SAMPLES * sizeof(*samples); + return avctx->block_align; +} + + +static av_cold void init_mdct_windows(void) +{ + int i; + + /** The mid and long windows uses the same sine window splitted + * in the middle and wrapped into zero/one regions as follows: + * + * region of "ones" + * ------------- + * / + * / 1st half + * / of the sine + * / window + * ---------/ + * zero region + * + * The mid and short windows are subsets of the long window. + */ + + /* Build "zero" region */ + memset(long_window, 0, sizeof(long_window)); + /* Build sine window region */ + short_window = &long_window[112]; + ff_sine_window_init(short_window,32); + /* Build "ones" region */ + for (i = 0; i < 112; i++) + long_window[144 + i] = 1.0f; + /* Save the mid window subset start */ + mid_window = &long_window[64]; + + /* Prepare the window table */ + window_per_band[0] = mid_window; + window_per_band[1] = mid_window; + window_per_band[2] = long_window; +} + +static av_cold int atrac1_decode_init(AVCodecContext *avctx) +{ + AT1Ctx *q = avctx->priv_data; + + avctx->sample_fmt = SAMPLE_FMT_FLT; + + q->channels = avctx->channels; + + /* Init the mdct transforms */ + ff_mdct_init(&q->mdct_ctx[0], 6, 1, -1.0/ (1<<15)); + ff_mdct_init(&q->mdct_ctx[1], 8, 1, -1.0/ (1<<15)); + ff_mdct_init(&q->mdct_ctx[2], 9, 1, -1.0/ (1<<15)); + init_mdct_windows(); + + atrac_generate_tables(); + + dsputil_init(&q->dsp, avctx); + + q->bands[0] = q->low; + q->bands[1] = q->mid; + q->bands[2] = q->high; + + /* Prepare the mdct overlap buffers */ + q->SUs[0].spectrum[0] = q->SUs[0].spec1; + q->SUs[0].spectrum[1] = q->SUs[0].spec2; + q->SUs[1].spectrum[0] = q->SUs[1].spec1; + q->SUs[1].spectrum[1] = q->SUs[1].spec2; + + return 0; +} + +AVCodec atrac1_decoder = { + .name = "atrac1", + .type = CODEC_TYPE_AUDIO, + .id = CODEC_ID_ATRAC1, + .priv_data_size = sizeof(AT1Ctx), + .init = atrac1_decode_init, + .close = NULL, + .decode = atrac1_decode_frame, + .long_name = NULL_IF_CONFIG_SMALL("Atrac 1 (Adaptive TRansform Acoustic Coding)"), +}; diff --git a/libavcodec/atrac1data.h b/libavcodec/atrac1data.h new file mode 100644 index 0000000000..77641f2678 --- /dev/null +++ b/libavcodec/atrac1data.h @@ -0,0 +1,62 @@ +/* + * Atrac 1 compatible decoder data + * Copyright (c) 2009 Maxim Poliakovski + * Copyright (c) 2009 Benjamin Larsson + * + * 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 libavcodec/atrac1data.h + * Atrac 1 compatible decoder data + */ + +#ifndef AVCODEC_ATRAC1DATA_H +#define AVCODEC_ATRAC1DATA_H + +static const uint8_t bfu_amount_tab1[8] = {20, 28, 32, 36, 40, 44, 48, 52}; +static const uint8_t bfu_amount_tab2[4] = { 0, 112, 176, 208}; +static const uint8_t bfu_amount_tab3[8] = { 0, 24, 36, 48, 72, 108, 132, 156}; + +/** number of BFUs in each QMF band */ +static const uint8_t bfu_bands_t[4] = {0, 20, 36, 52}; + +/** number of spectral lines in each BFU + * block floating unit = group of spectral frequencies having the + * same quantization parameters like word length and scale factor + */ +static const uint8_t specs_per_bfu[52] = { + 8, 8, 8, 8, 4, 4, 4, 4, 8, 8, 8, 8, 6, 6, 6, 6, 6, 6, 6, 6, // low band + 6, 6, 6, 6, 7, 7, 7, 7, 9, 9, 9, 9, 10, 10, 10, 10, // midle band + 12, 12, 12, 12, 12, 12, 12, 12, 20, 20, 20, 20, 20, 20, 20, 20 // high band +}; + +/** start position of each BFU in the MDCT spectrum for the long mode */ +static const uint16_t bfu_start_long[52] = { + 0, 8, 16, 24, 32, 36, 40, 44, 48, 56, 64, 72, 80, 86, 92, 98, 104, 110, 116, 122, + 128, 134, 140, 146, 152, 159, 166, 173, 180, 189, 198, 207, 216, 226, 236, 246, + 256, 268, 280, 292, 304, 316, 328, 340, 352, 372, 392, 412, 432, 452, 472, 492, +}; + +/** start position of each BFU in the MDCT spectrum for the short mode */ +static const uint16_t bfu_start_short[52] = { + 0, 32, 64, 96, 8, 40, 72, 104, 12, 44, 76, 108, 20, 52, 84, 116, 26, 58, 90, 122, + 128, 160, 192, 224, 134, 166, 198, 230, 141, 173, 205, 237, 150, 182, 214, 246, + 256, 288, 320, 352, 384, 416, 448, 480, 268, 300, 332, 364, 396, 428, 460, 492 +}; + +#endif /* AVCODEC_ATRAC1DATA_H */