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1  /*
2   * Copyright (C) 2016 foo86
3   *
4   * This file is part of FFmpeg.
5   *
6   * FFmpeg is free software; you can redistribute it and/or
7   * modify it under the terms of the GNU Lesser General Public
8   * License as published by the Free Software Foundation; either
9   * version 2.1 of the License, or (at your option) any later version.
10   *
11   * FFmpeg is distributed in the hope that it will be useful,
12   * but WITHOUT ANY WARRANTY; without even the implied warranty of
13   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   * Lesser General Public License for more details.
15   *
16   * You should have received a copy of the GNU Lesser General Public
17   * License along with FFmpeg; if not, write to the Free Software
18   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19   */
20  
21  #ifndef AVCODEC_DCA_CORE_H
22  #define AVCODEC_DCA_CORE_H
23  
24  #include "libavutil/float_dsp.h"
25  #include "libavutil/fixed_dsp.h"
26  #include "libavutil/mem_internal.h"
27  
28  #include "avcodec.h"
29  #include "get_bits.h"
30  #include "dca.h"
31  #include "dca_exss.h"
32  #include "dcadsp.h"
33  #include "dcadct.h"
34  #include "dcamath.h"
35  #include "dcahuff.h"
36  #include "fft.h"
37  #include "synth_filter.h"
38  
39  #define DCA_CHANNELS            7
40  #define DCA_SUBBANDS            32
41  #define DCA_SUBBANDS_X96        64
42  #define DCA_SUBFRAMES           16
43  #define DCA_SUBBAND_SAMPLES     8
44  #define DCA_PCMBLOCK_SAMPLES    32
45  #define DCA_LFE_HISTORY         8
46  #define DCA_ABITS_MAX           26
47  
48  #define DCA_CORE_CHANNELS_MAX       6
49  #define DCA_DMIX_CHANNELS_MAX       4
50  #define DCA_XXCH_CHANNELS_MAX       2
51  #define DCA_EXSS_CHANNELS_MAX       8
52  #define DCA_EXSS_CHSETS_MAX         4
53  
54  #define DCA_FILTER_MODE_X96     0x01
55  #define DCA_FILTER_MODE_FIXED   0x02
56  
57  enum DCACoreAudioMode {
58      DCA_AMODE_MONO,             // Mode 0: A (mono)
59      DCA_AMODE_MONO_DUAL,        // Mode 1: A + B (dual mono)
60      DCA_AMODE_STEREO,           // Mode 2: L + R (stereo)
61      DCA_AMODE_STEREO_SUMDIFF,   // Mode 3: (L+R) + (L-R) (sum-diff)
62      DCA_AMODE_STEREO_TOTAL,     // Mode 4: LT + RT (left and right total)
63      DCA_AMODE_3F,               // Mode 5: C + L + R
64      DCA_AMODE_2F1R,             // Mode 6: L + R + S
65      DCA_AMODE_3F1R,             // Mode 7: C + L + R + S
66      DCA_AMODE_2F2R,             // Mode 8: L + R + SL + SR
67      DCA_AMODE_3F2R,             // Mode 9: C + L + R + SL + SR
68  
69      DCA_AMODE_COUNT
70  };
71  
72  enum DCACoreExtAudioType {
73      DCA_EXT_AUDIO_XCH   = 0,
74      DCA_EXT_AUDIO_X96   = 2,
75      DCA_EXT_AUDIO_XXCH  = 6
76  };
77  
78  enum DCACoreLFEFlag {
79      DCA_LFE_FLAG_NONE,
80      DCA_LFE_FLAG_128,
81      DCA_LFE_FLAG_64,
82      DCA_LFE_FLAG_INVALID
83  };
84  
85  typedef struct DCADSPData {
86      union {
87          struct {
88              DECLARE_ALIGNED(32, float, hist1)[1024];
89              DECLARE_ALIGNED(32, float, hist2)[64];
90          } flt;
91          struct {
92              DECLARE_ALIGNED(32, int32_t, hist1)[1024];
93              DECLARE_ALIGNED(32, int32_t, hist2)[64];
94          } fix;
95      } u;
96      int offset;
97  } DCADSPData;
98  
99  typedef struct DCACoreDecoder {
100      AVCodecContext  *avctx;
101      GetBitContext   gb;
102      GetBitContext   gb_in;
103  
104      // Bit stream header
105      int     crc_present;        ///< CRC present flag
106      int     npcmblocks;         ///< Number of PCM sample blocks
107      int     frame_size;         ///< Primary frame byte size
108      int     audio_mode;         ///< Audio channel arrangement
109      int     sample_rate;        ///< Core audio sampling frequency
110      int     bit_rate;           ///< Transmission bit rate
111      int     drc_present;        ///< Embedded dynamic range flag
112      int     ts_present;         ///< Embedded time stamp flag
113      int     aux_present;        ///< Auxiliary data flag
114      int     ext_audio_type;     ///< Extension audio descriptor flag
115      int     ext_audio_present;  ///< Extended coding flag
116      int     sync_ssf;           ///< Audio sync word insertion flag
117      int     lfe_present;        ///< Low frequency effects flag
118      int     predictor_history;  ///< Predictor history flag switch
119      int     filter_perfect;     ///< Multirate interpolator switch
120      int     source_pcm_res;     ///< Source PCM resolution
121      int     es_format;          ///< Extended surround (ES) mastering flag
122      int     sumdiff_front;      ///< Front sum/difference flag
123      int     sumdiff_surround;   ///< Surround sum/difference flag
124  
125      // Primary audio coding header
126      int         nsubframes;     ///< Number of subframes
127      int         nchannels;      ///< Number of primary audio channels (incl. extension channels)
128      int         ch_mask;        ///< Speaker layout mask (incl. LFE and extension channels)
129      int8_t      nsubbands[DCA_CHANNELS];                ///< Subband activity count
130      int8_t      subband_vq_start[DCA_CHANNELS];         ///< High frequency VQ start subband
131      int8_t      joint_intensity_index[DCA_CHANNELS];    ///< Joint intensity coding index
132      int8_t      transition_mode_sel[DCA_CHANNELS];      ///< Transient mode code book
133      int8_t      scale_factor_sel[DCA_CHANNELS];         ///< Scale factor code book
134      int8_t      bit_allocation_sel[DCA_CHANNELS];       ///< Bit allocation quantizer select
135      int8_t      quant_index_sel[DCA_CHANNELS][DCA_CODE_BOOKS];  ///< Quantization index codebook select
136      int32_t     scale_factor_adj[DCA_CHANNELS][DCA_CODE_BOOKS]; ///< Scale factor adjustment
137  
138      // Primary audio coding side information
139      int8_t      nsubsubframes[DCA_SUBFRAMES];   ///< Subsubframe count for each subframe
140      int8_t      prediction_mode[DCA_CHANNELS][DCA_SUBBANDS_X96];            ///< Prediction mode
141      int16_t     prediction_vq_index[DCA_CHANNELS][DCA_SUBBANDS_X96];        ///< Prediction coefficients VQ address
142      int8_t      bit_allocation[DCA_CHANNELS][DCA_SUBBANDS_X96];             ///< Bit allocation index
143      int8_t      transition_mode[DCA_SUBFRAMES][DCA_CHANNELS][DCA_SUBBANDS]; ///< Transition mode
144      int32_t     scale_factors[DCA_CHANNELS][DCA_SUBBANDS][2];               ///< Scale factors (2x for transients and X96)
145      int8_t      joint_scale_sel[DCA_CHANNELS];                              ///< Joint subband codebook select
146      int32_t     joint_scale_factors[DCA_CHANNELS][DCA_SUBBANDS_X96];        ///< Scale factors for joint subband coding
147  
148      // Auxiliary data
149      int     prim_dmix_embedded; ///< Auxiliary dynamic downmix flag
150      int     prim_dmix_type;     ///< Auxiliary primary channel downmix type
151      int     prim_dmix_coeff[DCA_DMIX_CHANNELS_MAX * DCA_CORE_CHANNELS_MAX]; ///< Dynamic downmix code coefficients
152  
153      // Core extensions
154      int     ext_audio_mask;     ///< Bit mask of fully decoded core extensions
155  
156      // XCH extension data
157      int     xch_pos;    ///< Bit position of XCH frame in core substream
158  
159      // XXCH extension data
160      int     xxch_crc_present;       ///< CRC presence flag for XXCH channel set header
161      int     xxch_mask_nbits;        ///< Number of bits for loudspeaker mask
162      int     xxch_core_mask;         ///< Core loudspeaker activity mask
163      int     xxch_spkr_mask;         ///< Loudspeaker layout mask
164      int     xxch_dmix_embedded;     ///< Downmix already performed by encoder
165      int     xxch_dmix_scale_inv;    ///< Downmix scale factor
166      int     xxch_dmix_mask[DCA_XXCH_CHANNELS_MAX];  ///< Downmix channel mapping mask
167      int     xxch_dmix_coeff[DCA_XXCH_CHANNELS_MAX * DCA_CORE_CHANNELS_MAX];     ///< Downmix coefficients
168      int     xxch_pos;   ///< Bit position of XXCH frame in core substream
169  
170      // X96 extension data
171      int     x96_rev_no;         ///< X96 revision number
172      int     x96_crc_present;    ///< CRC presence flag for X96 channel set header
173      int     x96_nchannels;      ///< Number of primary channels in X96 extension
174      int     x96_high_res;       ///< X96 high resolution flag
175      int     x96_subband_start;  ///< First encoded subband in X96 extension
176      int     x96_rand;           ///< Random seed for generating samples for unallocated X96 subbands
177      int     x96_pos;            ///< Bit position of X96 frame in core substream
178  
179      // Sample buffers
180      unsigned int    x96_subband_size;
181      int32_t         *x96_subband_buffer;    ///< X96 subband sample buffer base
182      int32_t         *x96_subband_samples[DCA_CHANNELS][DCA_SUBBANDS_X96];   ///< X96 subband samples
183  
184      unsigned int    subband_size;
185      int32_t         *subband_buffer;    ///< Subband sample buffer base
186      int32_t         *subband_samples[DCA_CHANNELS][DCA_SUBBANDS];   ///< Subband samples
187      int32_t         *lfe_samples;    ///< Decimated LFE samples
188  
189      // DSP contexts
190      DCADSPData              dcadsp_data[DCA_CHANNELS];    ///< FIR history buffers
191      DCADSPContext           *dcadsp;
192      DCADCTContext           dcadct;
193      FFTContext              imdct[2];
194      SynthFilterContext      synth;
195      AVFloatDSPContext       *float_dsp;
196      AVFixedDSPContext       *fixed_dsp;
197  
198      // PCM output data
199      unsigned int    output_size;
200      void            *output_buffer;                         ///< PCM output buffer base
201      int32_t         *output_samples[DCA_SPEAKER_COUNT];     ///< PCM output for fixed point mode
202      int32_t         output_history_lfe_fixed;               ///< LFE PCM history for X96 filter
203      float           output_history_lfe_float;               ///< LFE PCM history for X96 filter
204  
205      int     ch_remap[DCA_SPEAKER_COUNT];   ///< Channel to speaker map
206      int     request_mask;   ///< Requested channel layout (for stereo downmix)
207  
208      int     npcmsamples;    ///< Number of PCM samples per channel
209      int     output_rate;    ///< Output sample rate (1x or 2x header rate)
210  
211      int     filter_mode;    ///< Previous filtering mode for detecting changes
212  } DCACoreDecoder;
213  
ff_dca_core_map_spkr(DCACoreDecoder * core,int spkr)214  static inline int ff_dca_core_map_spkr(DCACoreDecoder *core, int spkr)
215  {
216      if (core->ch_mask & (1U << spkr))
217          return spkr;
218      if (spkr == DCA_SPEAKER_Lss && (core->ch_mask & DCA_SPEAKER_MASK_Ls))
219          return DCA_SPEAKER_Ls;
220      if (spkr == DCA_SPEAKER_Rss && (core->ch_mask & DCA_SPEAKER_MASK_Rs))
221          return DCA_SPEAKER_Rs;
222      return -1;
223  }
224  
ff_dca_core_dequantize(int32_t * output,const int32_t * input,int32_t step_size,int32_t scale,int residual,int len)225  static inline void ff_dca_core_dequantize(int32_t *output, const int32_t *input,
226                                            int32_t step_size, int32_t scale, int residual, int len)
227  {
228      // Account for quantizer step size
229      int64_t step_scale = (int64_t)step_size * scale;
230      int n, shift = 0;
231  
232      // Limit scale factor resolution to 22 bits
233      if (step_scale > (1 << 23)) {
234          shift = av_log2(step_scale >> 23) + 1;
235          step_scale >>= shift;
236      }
237  
238      // Scale the samples
239      if (residual) {
240          for (n = 0; n < len; n++)
241              output[n] += clip23(norm__(input[n] * step_scale, 22 - shift));
242      } else {
243          for (n = 0; n < len; n++)
244              output[n]  = clip23(norm__(input[n] * step_scale, 22 - shift));
245      }
246  }
247  
248  int ff_dca_core_parse(DCACoreDecoder *s, const uint8_t *data, int size);
249  int ff_dca_core_parse_exss(DCACoreDecoder *s, const uint8_t *data, DCAExssAsset *asset);
250  int ff_dca_core_filter_fixed(DCACoreDecoder *s, int x96_synth);
251  int ff_dca_core_filter_frame(DCACoreDecoder *s, AVFrame *frame);
252  av_cold void ff_dca_core_flush(DCACoreDecoder *s);
253  av_cold int ff_dca_core_init(DCACoreDecoder *s);
254  av_cold void ff_dca_core_close(DCACoreDecoder *s);
255  
256  #endif
257