Libav
ra288.c
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1 /*
2  * RealAudio 2.0 (28.8K)
3  * Copyright (c) 2003 The FFmpeg project
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
23 #include "libavutil/float_dsp.h"
24 #include "libavutil/internal.h"
25 
26 #define BITSTREAM_READER_LE
27 #include "avcodec.h"
28 #include "celp_filters.h"
29 #include "get_bits.h"
30 #include "internal.h"
31 #include "lpc.h"
32 #include "ra288.h"
33 
34 #define MAX_BACKWARD_FILTER_ORDER 36
35 #define MAX_BACKWARD_FILTER_LEN 40
36 #define MAX_BACKWARD_FILTER_NONREC 35
37 
38 #define RA288_BLOCK_SIZE 5
39 #define RA288_BLOCKS_PER_FRAME 32
40 
41 typedef struct RA288Context {
43  DECLARE_ALIGNED(32, float, sp_lpc)[FFALIGN(36, 16)];
44  DECLARE_ALIGNED(32, float, gain_lpc)[FFALIGN(10, 16)];
45 
49  float sp_hist[111];
50 
52  float sp_rec[37];
53 
57  float gain_hist[38];
58 
60  float gain_rec[11];
61 } RA288Context;
62 
64 {
65  RA288Context *ractx = avctx->priv_data;
66 
67  avctx->channels = 1;
70 
72 
73  return 0;
74 }
75 
76 static void convolve(float *tgt, const float *src, int len, int n)
77 {
78  for (; n >= 0; n--)
79  tgt[n] = avpriv_scalarproduct_float_c(src, src - n, len);
80 
81 }
82 
83 static void decode(RA288Context *ractx, float gain, int cb_coef)
84 {
85  int i;
86  double sumsum;
87  float sum, buffer[5];
88  float *block = ractx->sp_hist + 70 + 36; // current block
89  float *gain_block = ractx->gain_hist + 28;
90 
91  memmove(ractx->sp_hist + 70, ractx->sp_hist + 75, 36*sizeof(*block));
92 
93  /* block 46 of G.728 spec */
94  sum = 32.0;
95  for (i=0; i < 10; i++)
96  sum -= gain_block[9-i] * ractx->gain_lpc[i];
97 
98  /* block 47 of G.728 spec */
99  sum = av_clipf(sum, 0, 60);
100 
101  /* block 48 of G.728 spec */
102  /* exp(sum * 0.1151292546497) == pow(10.0,sum/20) */
103  sumsum = exp(sum * 0.1151292546497) * gain * (1.0/(1<<23));
104 
105  for (i=0; i < 5; i++)
106  buffer[i] = codetable[cb_coef][i] * sumsum;
107 
108  sum = avpriv_scalarproduct_float_c(buffer, buffer, 5) * ((1 << 24) / 5.0);
109 
110  sum = FFMAX(sum, 1);
111 
112  /* shift and store */
113  memmove(gain_block, gain_block + 1, 9 * sizeof(*gain_block));
114 
115  gain_block[9] = 10 * log10(sum) - 32;
116 
117  ff_celp_lp_synthesis_filterf(block, ractx->sp_lpc, buffer, 5, 36);
118 }
119 
132 static void do_hybrid_window(RA288Context *ractx,
133  int order, int n, int non_rec, float *out,
134  float *hist, float *out2, const float *window)
135 {
136  int i;
137  float buffer1[MAX_BACKWARD_FILTER_ORDER + 1];
138  float buffer2[MAX_BACKWARD_FILTER_ORDER + 1];
142 
143  ractx->fdsp.vector_fmul(work, window, hist, FFALIGN(order + n + non_rec, 16));
144 
145  convolve(buffer1, work + order , n , order);
146  convolve(buffer2, work + order + n, non_rec, order);
147 
148  for (i=0; i <= order; i++) {
149  out2[i] = out2[i] * 0.5625 + buffer1[i];
150  out [i] = out2[i] + buffer2[i];
151  }
152 
153  /* Multiply by the white noise correcting factor (WNCF). */
154  *out *= 257.0 / 256.0;
155 }
156 
160 static void backward_filter(RA288Context *ractx,
161  float *hist, float *rec, const float *window,
162  float *lpc, const float *tab,
163  int order, int n, int non_rec, int move_size)
164 {
165  float temp[MAX_BACKWARD_FILTER_ORDER+1];
166 
167  do_hybrid_window(ractx, order, n, non_rec, temp, hist, rec, window);
168 
169  if (!compute_lpc_coefs(temp, order, lpc, 0, 1, 1))
170  ractx->fdsp.vector_fmul(lpc, lpc, tab, FFALIGN(order, 16));
171 
172  memmove(hist, hist + n, move_size*sizeof(*hist));
173 }
174 
175 static int ra288_decode_frame(AVCodecContext * avctx, void *data,
176  int *got_frame_ptr, AVPacket *avpkt)
177 {
178  AVFrame *frame = data;
179  const uint8_t *buf = avpkt->data;
180  int buf_size = avpkt->size;
181  float *out;
182  int i, ret;
183  RA288Context *ractx = avctx->priv_data;
184  GetBitContext gb;
185 
186  if (buf_size < avctx->block_align) {
187  av_log(avctx, AV_LOG_ERROR,
188  "Error! Input buffer is too small [%d<%d]\n",
189  buf_size, avctx->block_align);
190  return AVERROR_INVALIDDATA;
191  }
192 
193  /* get output buffer */
195  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
196  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
197  return ret;
198  }
199  out = (float *)frame->data[0];
200 
201  init_get_bits(&gb, buf, avctx->block_align * 8);
202 
203  for (i=0; i < RA288_BLOCKS_PER_FRAME; i++) {
204  float gain = amptable[get_bits(&gb, 3)];
205  int cb_coef = get_bits(&gb, 6 + (i&1));
206 
207  decode(ractx, gain, cb_coef);
208 
209  memcpy(out, &ractx->sp_hist[70 + 36], RA288_BLOCK_SIZE * sizeof(*out));
210  out += RA288_BLOCK_SIZE;
211 
212  if ((i & 7) == 3) {
213  backward_filter(ractx, ractx->sp_hist, ractx->sp_rec, syn_window,
214  ractx->sp_lpc, syn_bw_tab, 36, 40, 35, 70);
215 
216  backward_filter(ractx, ractx->gain_hist, ractx->gain_rec, gain_window,
217  ractx->gain_lpc, gain_bw_tab, 10, 8, 20, 28);
218  }
219  }
220 
221  *got_frame_ptr = 1;
222 
223  return avctx->block_align;
224 }
225 
227  .name = "real_288",
228  .long_name = NULL_IF_CONFIG_SMALL("RealAudio 2.0 (28.8K)"),
229  .type = AVMEDIA_TYPE_AUDIO,
230  .id = AV_CODEC_ID_RA_288,
231  .priv_data_size = sizeof(RA288Context),
234  .capabilities = AV_CODEC_CAP_DR1,
235 };
float sp_lpc[FFALIGN(36, 16)]
LPC coefficients for speech data (spec: A)
Definition: ra288.c:43
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
void ff_celp_lp_synthesis_filterf(float *out, const float *filter_coeffs, const float *in, int buffer_length, int filter_length)
LP synthesis filter.
Definition: celp_filters.c:83
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
float gain_lpc[FFALIGN(10, 16)]
LPC coefficients for gain (spec: GB)
Definition: ra288.c:44
static void backward_filter(RA288Context *ractx, float *hist, float *rec, const float *window, float *lpc, const float *tab, int order, int n, int non_rec, int move_size)
Backward synthesis filter, find the LPC coefficients from past speech data.
Definition: ra288.c:160
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:228
#define MAX_BACKWARD_FILTER_ORDER
Definition: ra288.c:34
int size
Definition: avcodec.h:1347
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:58
static void decode(RA288Context *ractx, float gain, int cb_coef)
Definition: ra288.c:83
AVCodec.
Definition: avcodec.h:3120
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2189
static const float amptable[8]
Definition: ra288.h:28
AVFloatDSPContext fdsp
Definition: ra288.c:42
static int16_t block[64]
Definition: dct.c:97
float avpriv_scalarproduct_float_c(const float *v1, const float *v2, int len)
Return the scalar product of two vectors.
Definition: float_dsp.c:104
static char buffer[20]
Definition: seek.c:32
float sp_hist[111]
speech data history (spec: SB).
Definition: ra288.c:49
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2160
uint8_t
#define av_cold
Definition: attributes.h:66
#define MAX_BACKWARD_FILTER_NONREC
Definition: ra288.c:36
void(* vector_fmul)(float *dst, const float *src0, const float *src1, int len)
Calculate the product of two vectors of floats and store the result in a vector of floats...
Definition: float_dsp.h:38
float gain_hist[38]
log-gain history (spec: SBLG).
Definition: ra288.c:57
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:1346
bitstream reader API header.
#define FFALIGN(x, a)
Definition: macros.h:48
#define src
Definition: vp8dsp.c:254
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:148
#define MAX_BACKWARD_FILTER_LEN
Definition: ra288.c:35
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1503
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
static void convolve(float *tgt, const float *src, int len, int n)
Definition: ra288.c:76
#define FFMAX(a, b)
Definition: common.h:64
static const float syn_window[FFALIGN(111, 16)]
Definition: ra288.h:100
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2203
AVCodec ff_ra_288_decoder
Definition: ra288.c:226
common internal API header
audio channel layout utility functions
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:788
#define RA288_BLOCKS_PER_FRAME
Definition: ra288.c:39
static const float gain_window[FFALIGN(38, 16)]
Definition: ra288.h:122
static const float syn_bw_tab[FFALIGN(36, 16)]
synthesis bandwidth broadening table
Definition: ra288.h:133
static const int16_t codetable[128][5]
Definition: ra288.h:33
Libavcodec external API header.
float sp_rec[37]
speech part of the gain autocorrelation (spec: REXP)
Definition: ra288.c:52
static int compute_lpc_coefs(const LPC_TYPE *autoc, int max_order, LPC_TYPE *lpc, int lpc_stride, int fail, int normalize)
Levinson-Durbin recursion.
Definition: lpc.h:150
main external API structure.
Definition: avcodec.h:1409
static void do_hybrid_window(RA288Context *ractx, int order, int n, int non_rec, float *out, float *hist, float *out2, const float *window)
Hybrid window filtering, see blocks 36 and 49 of the G.728 specification.
Definition: ra288.c:132
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:589
static const float gain_bw_tab[FFALIGN(10, 16)]
gain bandwidth broadening table
Definition: ra288.h:143
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:362
#define RA288_BLOCK_SIZE
Definition: ra288.c:38
av_cold void avpriv_float_dsp_init(AVFloatDSPContext *fdsp, int bit_exact)
Initialize a float DSP context.
Definition: float_dsp.c:115
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
static av_cold int ra288_decode_init(AVCodecContext *avctx)
Definition: ra288.c:63
static int ra288_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: ra288.c:175
common internal api header.
#define LOCAL_ALIGNED(a, t, v,...)
Definition: internal.h:100
float gain_rec[11]
recursive part of the gain autocorrelation (spec: REXPLG)
Definition: ra288.c:60
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:582
void * priv_data
Definition: avcodec.h:1451
int len
int channels
number of audio channels
Definition: avcodec.h:2153
static const struct twinvq_data tab
FILE * out
Definition: movenc.c:54
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1323
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:184
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:838