FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
ac3enc_fixed.c
Go to the documentation of this file.
1 /*
2  * The simplest AC-3 encoder
3  * Copyright (c) 2000 Fabrice Bellard
4  * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
5  * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /**
25  * @file
26  * fixed-point AC-3 encoder.
27  */
28 
29 #define FFT_FLOAT 0
30 #undef CONFIG_AC3ENC_FLOAT
31 #include "internal.h"
32 #include "audiodsp.h"
33 #include "ac3enc.h"
34 #include "eac3enc.h"
35 
36 #define AC3ENC_TYPE AC3ENC_TYPE_AC3_FIXED
37 #include "ac3enc_opts_template.c"
38 
39 static const AVClass ac3enc_class = {
40  .class_name = "Fixed-Point AC-3 Encoder",
41  .item_name = av_default_item_name,
42  .option = ac3_options,
43  .version = LIBAVUTIL_VERSION_INT,
44 };
45 
46 /*
47  * Normalize the input samples to use the maximum available precision.
48  * This assumes signed 16-bit input samples.
49  */
51 {
53  v = 14 - av_log2(v);
54  if (v > 0)
56  /* +6 to right-shift from 31-bit to 25-bit */
57  return v + 6;
58 }
59 
60 
61 /*
62  * Scale MDCT coefficients to 25-bit signed fixed-point.
63  */
65 {
66  int blk, ch;
67 
68  for (blk = 0; blk < s->num_blocks; blk++) {
69  AC3Block *block = &s->blocks[blk];
70  for (ch = 1; ch <= s->channels; ch++) {
72  block->coeff_shift[ch]);
73  }
74  }
75 }
76 
77 static void sum_square_butterfly(AC3EncodeContext *s, int64_t sum[4],
78  const int32_t *coef0, const int32_t *coef1,
79  int len)
80 {
81  s->ac3dsp.sum_square_butterfly_int32(sum, coef0, coef1, len);
82 }
83 
84 /*
85  * Clip MDCT coefficients to allowable range.
86  */
88  unsigned int len)
89 {
90  adsp->vector_clip_int32(coef, coef, COEF_MIN, COEF_MAX, len);
91 }
92 
93 
94 /*
95  * Calculate a single coupling coordinate.
96  */
97 static CoefType calc_cpl_coord(CoefSumType energy_ch, CoefSumType energy_cpl)
98 {
99  if (energy_cpl <= COEF_MAX) {
100  return 1048576;
101  } else {
102  uint64_t coord = energy_ch / (energy_cpl >> 24);
103  uint32_t coord32 = FFMIN(coord, 1073741824);
104  coord32 = ff_sqrt(coord32) << 9;
105  return FFMIN(coord32, COEF_MAX);
106  }
107 }
108 
109 
110 #include "ac3enc_template.c"
111 
112 
113 /**
114  * Finalize MDCT and free allocated memory.
115  *
116  * @param s AC-3 encoder private context
117  */
119 {
120  ff_mdct_end(&s->mdct);
121 }
122 
123 
124 /**
125  * Initialize MDCT tables.
126  *
127  * @param s AC-3 encoder private context
128  * @return 0 on success, negative error code on failure
129  */
131 {
132  int ret = ff_mdct_init(&s->mdct, 9, 0, -1.0);
134  return ret;
135 }
136 
137 
139 {
140  AC3EncodeContext *s = avctx->priv_data;
141  s->fixed_point = 1;
142  return ff_ac3_encode_init(avctx);
143 }
144 
145 
147  .name = "ac3_fixed",
148  .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
149  .type = AVMEDIA_TYPE_AUDIO,
150  .id = AV_CODEC_ID_AC3,
151  .priv_data_size = sizeof(AC3EncodeContext),
153  .encode2 = ff_ac3_fixed_encode_frame,
154  .close = ff_ac3_encode_close,
155  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16P,
157  .priv_class = &ac3enc_class,
158  .channel_layouts = ff_ac3_channel_layouts,
159  .defaults = ac3_defaults,
160 };
void(* ac3_rshift_int32)(int32_t *src, unsigned int len, unsigned int shift)
Right-shift each value in an array of int32_t by a specified amount.
Definition: ac3dsp.h:76
void(* vector_clip_int32)(int32_t *dst, const int32_t *src, int32_t min, int32_t max, unsigned int len)
Clip each element in an array of int32_t to a given minimum and maximum value.
Definition: audiodsp.h:46
const char * s
Definition: avisynth_c.h:768
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
#define AC3_MAX_COEFS
Definition: ac3.h:35
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
static av_cold int ac3_fixed_encode_init(AVCodecContext *avctx)
Definition: ac3enc_fixed.c:138
#define AC3_WINDOW_SIZE
Definition: ac3.h:39
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
int av_log2(unsigned v)
Definition: intmath.c:26
#define COEF_MIN
Definition: ac3enc.h:67
#define blk(i)
Definition: sha.c:185
AVCodec.
Definition: avcodec.h:3408
static int16_t block[64]
Definition: dct.c:115
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define av_cold
Definition: attributes.h:82
int(* ac3_max_msb_abs_int16)(const int16_t *src, int len)
Calculate the maximum MSB of the absolute value of each element in an array of int16_t.
Definition: ac3dsp.h:54
av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
Finalize encoding and free any memory allocated by the encoder.
Definition: ac3enc.c:2017
const int16_t ff_ac3_window[AC3_WINDOW_SIZE/2]
Definition: ac3tab.c:153
AC3DSPContext ac3dsp
AC-3 optimized functions.
Definition: ac3enc.h:170
#define ff_sqrt
Definition: mathops.h:206
int64_t CoefSumType
Definition: ac3enc.h:72
CoefType ** mdct_coef
MDCT coefficients.
Definition: ac3enc.h:134
const uint64_t ff_ac3_channel_layouts[19]
List of supported channel layouts.
Definition: ac3enc.c:81
int channels
total number of channels (nchans)
Definition: ac3enc.h:194
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3415
int fixed_point
indicates if fixed-point encoder is being used
Definition: ac3enc.h:176
#define ff_mdct_init
Definition: fft.h:169
Data for a single audio block.
Definition: ac3enc.h:133
#define FFMIN(a, b)
Definition: common.h:96
AudioDSPContext adsp
Definition: ac3enc.h:167
av_cold int ff_ac3_fixed_mdct_init(AC3EncodeContext *s)
Initialize MDCT tables.
Definition: ac3enc_fixed.c:130
int32_t
av_cold void ff_ac3_fixed_mdct_end(AC3EncodeContext *s)
Finalize MDCT and free allocated memory.
Definition: ac3enc_fixed.c:118
FFTContext mdct
FFT context for MDCT calculation.
Definition: ac3enc.h:171
static void scale_coefficients(AC3EncodeContext *s)
Definition: ac3enc_fixed.c:64
const SampleType * mdct_window
MDCT window function array.
Definition: ac3enc.h:172
static void clip_coefficients(AudioDSPContext *adsp, int32_t *coef, unsigned int len)
Definition: ac3enc_fixed.c:87
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
static CoefType calc_cpl_coord(CoefSumType energy_ch, CoefSumType energy_cpl)
Definition: ac3enc_fixed.c:97
main external API structure.
Definition: avcodec.h:1518
Describe the class of an AVClass context structure.
Definition: log.h:67
int ff_ac3_fixed_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
static const AVCodecDefault ac3_defaults[]
AC-3 encoder private context.
Definition: ac3enc.h:162
AC3Block blocks[AC3_MAX_BLOCKS]
per-block info
Definition: ac3enc.h:174
SampleType * windowed_samples
Definition: ac3enc.h:236
int num_blocks
number of blocks per frame
Definition: ac3enc.h:185
uint8_t coeff_shift[AC3_MAX_CHANNELS]
fixed-point coefficient shift values
Definition: ac3enc.h:144
#define COEF_MAX
Definition: ac3enc.h:68
AC-3 encoder float/fixed template.
common internal api header.
AVCodec ff_ac3_fixed_encoder
Definition: ac3enc_fixed.c:146
#define ff_mdct_end
Definition: fft.h:170
static const AVClass ac3enc_class
Definition: ac3enc_fixed.c:39
void(* ac3_lshift_int16)(int16_t *src, unsigned int len, unsigned int shift)
Left-shift each value in an array of int16_t by a specified amount.
Definition: ac3dsp.h:65
static const AVOption ac3_options[]
AVCodecContext * avctx
parent AVCodecContext
Definition: ac3enc.h:165
void * priv_data
Definition: avcodec.h:1545
int len
static int normalize_samples(AC3EncodeContext *s)
Definition: ac3enc_fixed.c:50
AC-3 encoder & E-AC-3 encoder common header.
void(* sum_square_butterfly_int32)(int64_t sum[4], const int32_t *coef0, const int32_t *coef1, int len)
Definition: ac3dsp.h:129
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:701
signed 16 bits, planar
Definition: samplefmt.h:67
static void sum_square_butterfly(AC3EncodeContext *s, int64_t sum[4], const int32_t *coef0, const int32_t *coef1, int len)
Definition: ac3enc_fixed.c:77
int32_t CoefType
Definition: ac3enc.h:71
E-AC-3 encoder.
uint8_t pi<< 24) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_U8,(uint64_t)((*(constuint8_t *) pi-0x80U))<< 56) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_S16,(uint64_t)(*(constint16_t *) pi)<< 48) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_S32,(uint64_t)(*(constint32_t *) pi)<< 32) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S64,(*(constint64_t *) pi >>56)+0x80) CONV_FUNC(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S64,*(constint64_t *) pi *(1.0f/(INT64_C(1)<< 63))) CONV_FUNC(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S64,*(constint64_t *) pi *(1.0/(INT64_C(1)<< 63))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_FLT, llrintf(*(constfloat *) pi *(INT64_C(1)<< 63))) CONV_FUNC(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31)))) CONV_FUNC(AV_SAMPLE_FMT_S64, int64_t, AV_SAMPLE_FMT_DBL, llrint(*(constdouble *) pi *(INT64_C(1)<< 63)))#defineFMT_PAIR_FUNC(out, in) staticconv_func_type *constfmt_pair_to_conv_functions[AV_SAMPLE_FMT_NB *AV_SAMPLE_FMT_NB]={FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_U8), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_S16), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_S32), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_FLT), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_DBL), FMT_PAIR_FUNC(AV_SAMPLE_FMT_U8, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_S64), FMT_PAIR_FUNC(AV_SAMPLE_FMT_S64, AV_SAMPLE_FMT_S64),};staticvoidcpy1(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, len);}staticvoidcpy2(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, 2 *len);}staticvoidcpy4(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, 4 *len);}staticvoidcpy8(uint8_t **dst, constuint8_t **src, intlen){memcpy(*dst,*src, 8 *len);}AudioConvert *swri_audio_convert_alloc(enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, constint *ch_map, intflags){AudioConvert *ctx;conv_func_type *f=fmt_pair_to_conv_functions[av_get_packed_sample_fmt(out_fmt)+AV_SAMPLE_FMT_NB *av_get_packed_sample_fmt(in_fmt)];if(!f) returnNULL;ctx=av_mallocz(sizeof(*ctx));if(!ctx) returnNULL;if(channels==1){in_fmt=av_get_planar_sample_fmt(in_fmt);out_fmt=av_get_planar_sample_fmt(out_fmt);}ctx->channels=channels;ctx->conv_f=f;ctx->ch_map=ch_map;if(in_fmt==AV_SAMPLE_FMT_U8||in_fmt==AV_SAMPLE_FMT_U8P) memset(ctx->silence, 0x80, sizeof(ctx->silence));if(out_fmt==in_fmt &&!ch_map){switch(av_get_bytes_per_sample(in_fmt)){case1:ctx->simd_f=cpy1;break;case2:ctx->simd_f=cpy2;break;case4:ctx->simd_f=cpy4;break;case8:ctx->simd_f=cpy8;break;}}if(HAVE_X86ASM &&1) swri_audio_convert_init_x86(ctx, out_fmt, in_fmt, channels);if(ARCH_ARM) swri_audio_convert_init_arm(ctx, out_fmt, in_fmt, channels);if(ARCH_AARCH64) swri_audio_convert_init_aarch64(ctx, out_fmt, in_fmt, channels);returnctx;}voidswri_audio_convert_free(AudioConvert **ctx){av_freep(ctx);}intswri_audio_convert(AudioConvert *ctx, AudioData *out, AudioData *in, intlen){intch;intoff=0;constintos=(out->planar?1:out->ch_count)*out->bps;unsignedmisaligned=0;av_assert0(ctx->channels==out->ch_count);if(ctx->in_simd_align_mask){intplanes=in->planar?in->ch_count:1;unsignedm=0;for(ch=0;ch< planes;ch++) m|=(intptr_t) in->ch[ch];misaligned|=m &ctx->in_simd_align_mask;}if(ctx->out_simd_align_mask){intplanes=out->planar?out->ch_count:1;unsignedm=0;for(ch=0;ch< planes;ch++) m|=(intptr_t) out->ch[ch];misaligned|=m &ctx->out_simd_align_mask;}if(ctx->simd_f &&!ctx->ch_map &&!misaligned){off=len &~15;av_assert1(off >=0);av_assert1(off<=len);av_assert2(ctx->channels==SWR_CH_MAX||!in->ch[ctx->channels]);if(off >0){if(out->planar==in->planar){intplanes=out->planar?out->ch_count:1;for(ch=0;ch< planes;ch++){ctx->simd_f(out-> ch ch
Definition: audioconvert.c:56
av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
Definition: ac3enc.c:2425