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gsmdec_template.c
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1 /*
2  * gsm 06.10 decoder
3  * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * GSM decoder
25  */
26 
27 #include "get_bits.h"
28 #include "gsm.h"
29 #include "gsmdec_data.h"
30 
31 static const int requant_tab[4][8] = {
32  { 0 },
33  { 0, 7 },
34  { 0, 2, 5, 7 },
35  { 0, 1, 2, 3, 4, 5, 6, 7 }
36 };
37 
38 static void apcm_dequant_add(GetBitContext *gb, int16_t *dst, const int *frame_bits)
39 {
40  int i, val;
41  int maxidx = get_bits(gb, 6);
42  const int16_t *tab = ff_gsm_dequant_tab[maxidx];
43  for (i = 0; i < 13; i++) {
44  val = get_bits(gb, frame_bits[i]);
45  dst[3*i] += tab[requant_tab[frame_bits[i]][val]];
46  }
47 }
48 
49 static inline int gsm_mult(int a, int b)
50 {
51  return (a * b + (1 << 14)) >> 15;
52 }
53 
54 static void long_term_synth(int16_t *dst, int lag, int gain_idx)
55 {
56  int i;
57  const int16_t *src = dst - lag;
58  uint16_t gain = ff_gsm_long_term_gain_tab[gain_idx];
59  for (i = 0; i < 40; i++)
60  dst[i] = gsm_mult(gain, src[i]);
61 }
62 
63 static inline int decode_log_area(int coded, int factor, int offset)
64 {
65  coded <<= 10;
66  coded -= offset;
67  return gsm_mult(coded, factor) << 1;
68 }
69 
70 static av_noinline int get_rrp(int filtered)
71 {
72  int abs = FFABS(filtered);
73  if (abs < 11059) abs <<= 1;
74  else if (abs < 20070) abs += 11059;
75  else abs = (abs >> 2) + 26112;
76  return filtered < 0 ? -abs : abs;
77 }
78 
79 static int filter_value(int in, int rrp[8], int v[9])
80 {
81  int i;
82  for (i = 7; i >= 0; i--) {
83  in -= gsm_mult(rrp[i], v[i]);
84  v[i + 1] = v[i] + gsm_mult(rrp[i], in);
85  }
86  v[0] = in;
87  return in;
88 }
89 
90 static void short_term_synth(GSMContext *ctx, int16_t *dst, const int16_t *src)
91 {
92  int i;
93  int rrp[8];
94  int *lar = ctx->lar[ctx->lar_idx];
95  int *lar_prev = ctx->lar[ctx->lar_idx ^ 1];
96  for (i = 0; i < 8; i++)
97  rrp[i] = get_rrp((lar_prev[i] >> 2) + (lar_prev[i] >> 1) + (lar[i] >> 2));
98  for (i = 0; i < 13; i++)
99  dst[i] = filter_value(src[i], rrp, ctx->v);
100 
101  for (i = 0; i < 8; i++)
102  rrp[i] = get_rrp((lar_prev[i] >> 1) + (lar [i] >> 1));
103  for (i = 13; i < 27; i++)
104  dst[i] = filter_value(src[i], rrp, ctx->v);
105 
106  for (i = 0; i < 8; i++)
107  rrp[i] = get_rrp((lar_prev[i] >> 2) + (lar [i] >> 1) + (lar[i] >> 2));
108  for (i = 27; i < 40; i++)
109  dst[i] = filter_value(src[i], rrp, ctx->v);
110 
111  for (i = 0; i < 8; i++)
112  rrp[i] = get_rrp(lar[i]);
113  for (i = 40; i < 160; i++)
114  dst[i] = filter_value(src[i], rrp, ctx->v);
115 
116  ctx->lar_idx ^= 1;
117 }
118 
119 static int postprocess(int16_t *data, int msr)
120 {
121  int i;
122  for (i = 0; i < 160; i++) {
123  msr = av_clip_int16(data[i] + gsm_mult(msr, 28180));
124  data[i] = av_clip_int16(msr << 1) & ~7;
125  }
126  return msr;
127 }
128 
129 static int gsm_decode_block(AVCodecContext *avctx, int16_t *samples,
130  GetBitContext *gb, int mode)
131 {
132  GSMContext *ctx = avctx->priv_data;
133  int i;
134  int16_t *ref_dst = ctx->ref_buf + 120;
135  int *lar = ctx->lar[ctx->lar_idx];
136  lar[0] = decode_log_area(get_bits(gb, 6), 13107, 1 << 15);
137  lar[1] = decode_log_area(get_bits(gb, 6), 13107, 1 << 15);
138  lar[2] = decode_log_area(get_bits(gb, 5), 13107, (1 << 14) + 2048*2);
139  lar[3] = decode_log_area(get_bits(gb, 5), 13107, (1 << 14) - 2560*2);
140  lar[4] = decode_log_area(get_bits(gb, 4), 19223, (1 << 13) + 94*2);
141  lar[5] = decode_log_area(get_bits(gb, 4), 17476, (1 << 13) - 1792*2);
142  lar[6] = decode_log_area(get_bits(gb, 3), 31454, (1 << 12) - 341*2);
143  lar[7] = decode_log_area(get_bits(gb, 3), 29708, (1 << 12) - 1144*2);
144 
145  for (i = 0; i < 4; i++) {
146  int lag = get_bits(gb, 7);
147  int gain_idx = get_bits(gb, 2);
148  int offset = get_bits(gb, 2);
149  lag = av_clip(lag, 40, 120);
150  long_term_synth(ref_dst, lag, gain_idx);
151  apcm_dequant_add(gb, ref_dst + offset, ff_gsm_apcm_bits[mode][i]);
152  ref_dst += 40;
153  }
154  memcpy(ctx->ref_buf, ctx->ref_buf + 160, 120 * sizeof(*ctx->ref_buf));
155  short_term_synth(ctx, samples, ctx->ref_buf + 120);
156  // for optimal speed this could be merged with short_term_synth,
157  // not done yet because it is a bit ugly
158  ctx->msr = postprocess(samples, ctx->msr);
159  return 0;
160 }
const char const char void * val
Definition: avisynth_c.h:634
float v
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static void short_term_synth(GSMContext *ctx, int16_t *dst, const int16_t *src)
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:260
const char * b
Definition: vf_curves.c:109
static const int requant_tab[4][8]
static av_noinline int get_rrp(int filtered)
static int gsm_mult(int a, int b)
int v[9]
Definition: gsmdec_data.h:34
mode
Definition: f_perms.c:27
static int decode_log_area(int coded, int factor, int offset)
bitstream reader API header.
static int gsm_decode_block(AVCodecContext *avctx, int16_t *samples, GetBitContext *gb, int mode)
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
const int16_t ff_gsm_dequant_tab[64][8]
Definition: gsmdec_data.c:29
static void long_term_synth(int16_t *dst, int lag, int gain_idx)
static int filter_value(int in, int rrp[8], int v[9])
#define FFABS(a)
Definition: common.h:61
static int postprocess(int16_t *data, int msr)
AVS_Value src
Definition: avisynth_c.h:482
main external API structure.
Definition: avcodec.h:1501
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
const uint16_t ff_gsm_long_term_gain_tab[4]
Definition: gsmdec_data.c:25
static void apcm_dequant_add(GetBitContext *gb, int16_t *dst, const int *frame_bits)
static const int factor[16]
Definition: vf_pp7.c:75
int16_t ref_buf[280]
Definition: gsmdec_data.h:33
int lar[2][8]
Definition: gsmdec_data.h:35
const int *const ff_gsm_apcm_bits[][4]
Definition: gsmdec_data.c:110
void * priv_data
Definition: avcodec.h:1543
static const struct twinvq_data tab
#define av_noinline
Definition: attributes.h:54