FFmpeg: libavcodec/atrac3plusdec.c Source File

FFmpeg
atrac3plusdec.c
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1 /*
2  * ATRAC3+ compatible decoder
3  *
4  * Copyright (c) 2010-2013 Maxim Poliakovski
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Sony ATRAC3+ compatible decoder.
26  *
27  * Container formats used to store its data:
28  * RIFF WAV (.at3) and Sony OpenMG (.oma, .aa3).
29  *
30  * Technical description of this codec can be found here:
31  * http://wiki.multimedia.cx/index.php?title=ATRAC3plus
32  *
33  * Kudos to Benjamin Larsson and Michael Karcher
34  * for their precious technical help!
35  */
36 
37 #include <stdint.h>
38 #include <string.h>
39 
40 #include "libavutil/channel_layout.h"
41 #include "libavutil/float_dsp.h"
42 #include "avcodec.h"
43 #include "get_bits.h"
44 #include "internal.h"
45 #include "atrac.h"
46 #include "atrac3plus.h"
47 
48  typedef struct ATRAC3PContext {
49   GetBitContext gb;
50   AVFloatDSPContext *fdsp;
51 
52   DECLARE_ALIGNED(32, float, samples)[2][ATRAC3P_FRAME_SAMPLES]; ///< quantized MDCT spectrum
53   DECLARE_ALIGNED(32, float, mdct_buf)[2][ATRAC3P_FRAME_SAMPLES]; ///< output of the IMDCT
54   DECLARE_ALIGNED(32, float, time_buf)[2][ATRAC3P_FRAME_SAMPLES]; ///< output of the gain compensation
55   DECLARE_ALIGNED(32, float, outp_buf)[2][ATRAC3P_FRAME_SAMPLES];
56 
57   AtracGCContext gainc_ctx; ///< gain compensation context
58   FFTContext mdct_ctx;
59   FFTContext ipqf_dct_ctx; ///< IDCT context used by IPQF
60 
61   Atrac3pChanUnitCtx *ch_units; ///< global channel units
62 
63   int num_channel_blocks; ///< number of channel blocks
64   uint8_t channel_blocks[5]; ///< channel configuration descriptor
65   uint64_t my_channel_layout; ///< current channel layout
66 } ATRAC3PContext;
67 
68  static av_cold int atrac3p_decode_close(AVCodecContext *avctx)
69 {
70  ATRAC3PContext *ctx = avctx->priv_data;
71 
72  av_freep(&ctx->ch_units);
73  av_freep(&ctx->fdsp);
74 
75  return 0;
76 }
77 
78  static av_cold int set_channel_params(ATRAC3PContext *ctx,
79  AVCodecContext *avctx)
80 {
81  memset(ctx->channel_blocks, 0, sizeof(ctx->channel_blocks));
82 
83  switch (avctx->channels) {
84  case 1:
85  if (avctx->channel_layout != AV_CH_FRONT_LEFT)
86  avctx->channel_layout = AV_CH_LAYOUT_MONO;
87 
88  ctx->num_channel_blocks = 1;
89  ctx->channel_blocks[0] = CH_UNIT_MONO;
90  break;
91  case 2:
92  avctx->channel_layout = AV_CH_LAYOUT_STEREO;
93  ctx->num_channel_blocks = 1;
94  ctx->channel_blocks[0] = CH_UNIT_STEREO;
95  break;
96  case 3:
97  avctx->channel_layout = AV_CH_LAYOUT_SURROUND;
98  ctx->num_channel_blocks = 2;
99  ctx->channel_blocks[0] = CH_UNIT_STEREO;
100  ctx->channel_blocks[1] = CH_UNIT_MONO;
101  break;
102  case 4:
103  avctx->channel_layout = AV_CH_LAYOUT_4POINT0;
104  ctx->num_channel_blocks = 3;
105  ctx->channel_blocks[0] = CH_UNIT_STEREO;
106  ctx->channel_blocks[1] = CH_UNIT_MONO;
107  ctx->channel_blocks[2] = CH_UNIT_MONO;
108  break;
109  case 6:
110  avctx->channel_layout = AV_CH_LAYOUT_5POINT1_BACK;
111  ctx->num_channel_blocks = 4;
112  ctx->channel_blocks[0] = CH_UNIT_STEREO;
113  ctx->channel_blocks[1] = CH_UNIT_MONO;
114  ctx->channel_blocks[2] = CH_UNIT_STEREO;
115  ctx->channel_blocks[3] = CH_UNIT_MONO;
116  break;
117  case 7:
118  avctx->channel_layout = AV_CH_LAYOUT_6POINT1_BACK;
119  ctx->num_channel_blocks = 5;
120  ctx->channel_blocks[0] = CH_UNIT_STEREO;
121  ctx->channel_blocks[1] = CH_UNIT_MONO;
122  ctx->channel_blocks[2] = CH_UNIT_STEREO;
123  ctx->channel_blocks[3] = CH_UNIT_MONO;
124  ctx->channel_blocks[4] = CH_UNIT_MONO;
125  break;
126  case 8:
127  avctx->channel_layout = AV_CH_LAYOUT_7POINT1;
128  ctx->num_channel_blocks = 5;
129  ctx->channel_blocks[0] = CH_UNIT_STEREO;
130  ctx->channel_blocks[1] = CH_UNIT_MONO;
131  ctx->channel_blocks[2] = CH_UNIT_STEREO;
132  ctx->channel_blocks[3] = CH_UNIT_STEREO;
133  ctx->channel_blocks[4] = CH_UNIT_MONO;
134  break;
135  default:
136  av_log(avctx, AV_LOG_ERROR,
137  "Unsupported channel count: %d!\n", avctx->channels);
138  return AVERROR_INVALIDDATA;
139  }
140 
141  return 0;
142 }
143 
144  static av_cold int atrac3p_decode_init(AVCodecContext *avctx)
145 {
146  ATRAC3PContext *ctx = avctx->priv_data;
147  int i, ch, ret;
148 
149  if (!avctx->block_align) {
150  av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
151  return AVERROR(EINVAL);
152  }
153 
154  ff_atrac3p_init_vlcs();
155 
156  /* initialize IPQF */
157  ff_mdct_init(&ctx->ipqf_dct_ctx, 5, 1, 32.0 / 32768.0);
158 
159  ff_atrac3p_init_imdct(avctx, &ctx->mdct_ctx);
160 
161  ff_atrac_init_gain_compensation(&ctx->gainc_ctx, 6, 2);
162 
163  ff_atrac3p_init_wave_synth();
164 
165  if ((ret = set_channel_params(ctx, avctx)) < 0)
166  return ret;
167 
168  ctx->my_channel_layout = avctx->channel_layout;
169 
170  ctx->ch_units = av_mallocz_array(ctx->num_channel_blocks, sizeof(*ctx->ch_units));
171  ctx->fdsp = avpriv_float_dsp_alloc(avctx->flags & CODEC_FLAG_BITEXACT);
172 
173  if (!ctx->ch_units || !ctx->fdsp) {
174  atrac3p_decode_close(avctx);
175  return AVERROR(ENOMEM);
176  }
177 
178  for (i = 0; i < ctx->num_channel_blocks; i++) {
179  for (ch = 0; ch < 2; ch++) {
180  ctx->ch_units[i].channels[ch].ch_num = ch;
181  ctx->ch_units[i].channels[ch].wnd_shape = &ctx->ch_units[i].channels[ch].wnd_shape_hist[0][0];
182  ctx->ch_units[i].channels[ch].wnd_shape_prev = &ctx->ch_units[i].channels[ch].wnd_shape_hist[1][0];
183  ctx->ch_units[i].channels[ch].gain_data = &ctx->ch_units[i].channels[ch].gain_data_hist[0][0];
184  ctx->ch_units[i].channels[ch].gain_data_prev = &ctx->ch_units[i].channels[ch].gain_data_hist[1][0];
185  ctx->ch_units[i].channels[ch].tones_info = &ctx->ch_units[i].channels[ch].tones_info_hist[0][0];
186  ctx->ch_units[i].channels[ch].tones_info_prev = &ctx->ch_units[i].channels[ch].tones_info_hist[1][0];
187  }
188 
189  ctx->ch_units[i].waves_info = &ctx->ch_units[i].wave_synth_hist[0];
190  ctx->ch_units[i].waves_info_prev = &ctx->ch_units[i].wave_synth_hist[1];
191  }
192 
193  avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
194 
195  return 0;
196 }
197 
198  static void decode_residual_spectrum(Atrac3pChanUnitCtx *ctx,
199  float out[2][ATRAC3P_FRAME_SAMPLES],
200  int num_channels,
201  AVCodecContext *avctx)
202 {
203  int i, sb, ch, qu, nspeclines, RNG_index;
204  float *dst, q;
205  int16_t *src;
206  /* calculate RNG table index for each subband */
207  int sb_RNG_index[ATRAC3P_SUBBANDS] = { 0 };
208 
209  if (ctx->mute_flag) {
210  for (ch = 0; ch < num_channels; ch++)
211  memset(out[ch], 0, ATRAC3P_FRAME_SAMPLES * sizeof(*out[ch]));
212  return;
213  }
214 
215  for (qu = 0, RNG_index = 0; qu < ctx->used_quant_units; qu++)
216  RNG_index += ctx->channels[0].qu_sf_idx[qu] +
217  ctx->channels[1].qu_sf_idx[qu];
218 
219  for (sb = 0; sb < ctx->num_coded_subbands; sb++, RNG_index += 128)
220  sb_RNG_index[sb] = RNG_index & 0x3FC;
221 
222  /* inverse quant and power compensation */
223  for (ch = 0; ch < num_channels; ch++) {
224  /* clear channel's residual spectrum */
225  memset(out[ch], 0, ATRAC3P_FRAME_SAMPLES * sizeof(*out[ch]));
226 
227  for (qu = 0; qu < ctx->used_quant_units; qu++) {
228  src = &ctx->channels[ch].spectrum[ff_atrac3p_qu_to_spec_pos[qu]];
229  dst = &out[ch][ff_atrac3p_qu_to_spec_pos[qu]];
230  nspeclines = ff_atrac3p_qu_to_spec_pos[qu + 1] -
231  ff_atrac3p_qu_to_spec_pos[qu];
232 
233  if (ctx->channels[ch].qu_wordlen[qu] > 0) {
234  q = ff_atrac3p_sf_tab[ctx->channels[ch].qu_sf_idx[qu]] *
235  ff_atrac3p_mant_tab[ctx->channels[ch].qu_wordlen[qu]];
236  for (i = 0; i < nspeclines; i++)
237  dst[i] = src[i] * q;
238  }
239  }
240 
241  for (sb = 0; sb < ctx->num_coded_subbands; sb++)
242  ff_atrac3p_power_compensation(ctx, ch, &out[ch][0],
243  sb_RNG_index[sb], sb);
244  }
245 
246  if (ctx->unit_type == CH_UNIT_STEREO) {
247  for (sb = 0; sb < ctx->num_coded_subbands; sb++) {
248  if (ctx->swap_channels[sb]) {
249  for (i = 0; i < ATRAC3P_SUBBAND_SAMPLES; i++)
250  FFSWAP(float, out[0][sb * ATRAC3P_SUBBAND_SAMPLES + i],
251  out[1][sb * ATRAC3P_SUBBAND_SAMPLES + i]);
252  }
253 
254  /* flip coefficients' sign if requested */
255  if (ctx->negate_coeffs[sb])
256  for (i = 0; i < ATRAC3P_SUBBAND_SAMPLES; i++)
257  out[1][sb * ATRAC3P_SUBBAND_SAMPLES + i] = -(out[1][sb * ATRAC3P_SUBBAND_SAMPLES + i]);
258  }
259  }
260 }
261 
262  static void reconstruct_frame(ATRAC3PContext *ctx, Atrac3pChanUnitCtx *ch_unit,
263  int num_channels, AVCodecContext *avctx)
264 {
265  int ch, sb;
266 
267  for (ch = 0; ch < num_channels; ch++) {
268  for (sb = 0; sb < ch_unit->num_subbands; sb++) {
269  /* inverse transform and windowing */
270  ff_atrac3p_imdct(ctx->fdsp, &ctx->mdct_ctx,
271  &ctx->samples[ch][sb * ATRAC3P_SUBBAND_SAMPLES],
272  &ctx->mdct_buf[ch][sb * ATRAC3P_SUBBAND_SAMPLES],
273  (ch_unit->channels[ch].wnd_shape_prev[sb] << 1) +
274  ch_unit->channels[ch].wnd_shape[sb], sb);
275 
276  /* gain compensation and overlapping */
277  ff_atrac_gain_compensation(&ctx->gainc_ctx,
278  &ctx->mdct_buf[ch][sb * ATRAC3P_SUBBAND_SAMPLES],
279  &ch_unit->prev_buf[ch][sb * ATRAC3P_SUBBAND_SAMPLES],
280  &ch_unit->channels[ch].gain_data_prev[sb],
281  &ch_unit->channels[ch].gain_data[sb],
282  ATRAC3P_SUBBAND_SAMPLES,
283  &ctx->time_buf[ch][sb * ATRAC3P_SUBBAND_SAMPLES]);
284  }
285 
286  /* zero unused subbands in both output and overlapping buffers */
287  memset(&ch_unit->prev_buf[ch][ch_unit->num_subbands * ATRAC3P_SUBBAND_SAMPLES],
288  0,
289  (ATRAC3P_SUBBANDS - ch_unit->num_subbands) *
290  ATRAC3P_SUBBAND_SAMPLES *
291  sizeof(ch_unit->prev_buf[ch][ch_unit->num_subbands * ATRAC3P_SUBBAND_SAMPLES]));
292  memset(&ctx->time_buf[ch][ch_unit->num_subbands * ATRAC3P_SUBBAND_SAMPLES],
293  0,
294  (ATRAC3P_SUBBANDS - ch_unit->num_subbands) *
295  ATRAC3P_SUBBAND_SAMPLES *
296  sizeof(ctx->time_buf[ch][ch_unit->num_subbands * ATRAC3P_SUBBAND_SAMPLES]));
297 
298  /* resynthesize and add tonal signal */
299  if (ch_unit->waves_info->tones_present ||
300  ch_unit->waves_info_prev->tones_present) {
301  for (sb = 0; sb < ch_unit->num_subbands; sb++)
302  if (ch_unit->channels[ch].tones_info[sb].num_wavs ||
303  ch_unit->channels[ch].tones_info_prev[sb].num_wavs) {
304  ff_atrac3p_generate_tones(ch_unit, ctx->fdsp, ch, sb,
305  &ctx->time_buf[ch][sb * 128]);
306  }
307  }
308 
309  /* subband synthesis and acoustic signal output */
310  ff_atrac3p_ipqf(&ctx->ipqf_dct_ctx, &ch_unit->ipqf_ctx[ch],
311  &ctx->time_buf[ch][0], &ctx->outp_buf[ch][0]);
312  }
313 
314  /* swap window shape and gain control buffers. */
315  for (ch = 0; ch < num_channels; ch++) {
316  FFSWAP(uint8_t *, ch_unit->channels[ch].wnd_shape,
317  ch_unit->channels[ch].wnd_shape_prev);
318  FFSWAP(AtracGainInfo *, ch_unit->channels[ch].gain_data,
319  ch_unit->channels[ch].gain_data_prev);
320  FFSWAP(Atrac3pWavesData *, ch_unit->channels[ch].tones_info,
321  ch_unit->channels[ch].tones_info_prev);
322  }
323 
324  FFSWAP(Atrac3pWaveSynthParams *, ch_unit->waves_info, ch_unit->waves_info_prev);
325 }
326 
327  static int atrac3p_decode_frame(AVCodecContext *avctx, void *data,
328  int *got_frame_ptr, AVPacket *avpkt)
329 {
330  ATRAC3PContext *ctx = avctx->priv_data;
331  AVFrame *frame = data;
332  int i, ret, ch_unit_id, ch_block = 0, out_ch_index = 0, channels_to_process;
333  float **samples_p = (float **)frame->extended_data;
334 
335  frame->nb_samples = ATRAC3P_FRAME_SAMPLES;
336  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
337  return ret;
338 
339  if ((ret = init_get_bits8(&ctx->gb, avpkt->data, avpkt->size)) < 0)
340  return ret;
341 
342  if (get_bits1(&ctx->gb)) {
343  av_log(avctx, AV_LOG_ERROR, "Invalid start bit!\n");
344  return AVERROR_INVALIDDATA;
345  }
346 
347  while (get_bits_left(&ctx->gb) >= 2 &&
348  (ch_unit_id = get_bits(&ctx->gb, 2)) != CH_UNIT_TERMINATOR) {
349  if (ch_unit_id == CH_UNIT_EXTENSION) {
350  avpriv_report_missing_feature(avctx, "Channel unit extension");
351  return AVERROR_PATCHWELCOME;
352  }
353  if (ch_block >= ctx->num_channel_blocks ||
354  ctx->channel_blocks[ch_block] != ch_unit_id) {
355  av_log(avctx, AV_LOG_ERROR,
356  "Frame data doesn't match channel configuration!\n");
357  return AVERROR_INVALIDDATA;
358  }
359 
360  ctx->ch_units[ch_block].unit_type = ch_unit_id;
361  channels_to_process = ch_unit_id + 1;
362 
363  if ((ret = ff_atrac3p_decode_channel_unit(&ctx->gb,
364  &ctx->ch_units[ch_block],
365  channels_to_process,
366  avctx)) < 0)
367  return ret;
368 
369  decode_residual_spectrum(&ctx->ch_units[ch_block], ctx->samples,
370  channels_to_process, avctx);
371  reconstruct_frame(ctx, &ctx->ch_units[ch_block],
372  channels_to_process, avctx);
373 
374  for (i = 0; i < channels_to_process; i++)
375  memcpy(samples_p[out_ch_index + i], ctx->outp_buf[i],
376  ATRAC3P_FRAME_SAMPLES * sizeof(**samples_p));
377 
378  ch_block++;
379  out_ch_index += channels_to_process;
380  }
381 
382  *got_frame_ptr = 1;
383 
384  return avctx->block_align;
385 }
386 
387  AVCodec ff_atrac3p_decoder = {
388  .name = "atrac3plus",
389  .long_name = NULL_IF_CONFIG_SMALL("ATRAC3+ (Adaptive TRansform Acoustic Coding 3+)"),
390  .type = AVMEDIA_TYPE_AUDIO,
391  .id = AV_CODEC_ID_ATRAC3P,
392  .priv_data_size = sizeof(ATRAC3PContext),
393  .init = atrac3p_decode_init,
394  .close = atrac3p_decode_close,
395  .decode = atrac3p_decode_frame,
396 };
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