FFmpeg
tx.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "tx_priv.h"
20 
21 /* Calculates the modular multiplicative inverse, not fast, replace */
22 static av_always_inline int mulinv(int n, int m)
23 {
24  n = n % m;
25  for (int x = 1; x < m; x++)
26  if (((n * x) % m) == 1)
27  return x;
28  av_assert0(0); /* Never reached */
29 }
30 
31 /* Guaranteed to work for any n, m where gcd(n, m) == 1 */
33 {
34  int *in_map, *out_map;
35  const int n = s->n;
36  const int m = s->m;
37  const int inv = s->inv;
38  const int type = s->type;
39  const int len = n*m;
40  const int m_inv = mulinv(m, n);
41  const int n_inv = mulinv(n, m);
42  const int mdct = type == AV_TX_FLOAT_MDCT || type == AV_TX_DOUBLE_MDCT;
43 
44  if (!(s->pfatab = av_malloc(2*len*sizeof(*s->pfatab))))
45  return AVERROR(ENOMEM);
46 
47  in_map = s->pfatab;
48  out_map = s->pfatab + n*m;
49 
50  /* Ruritanian map for input, CRT map for output, can be swapped */
51  for (int j = 0; j < m; j++) {
52  for (int i = 0; i < n; i++) {
53  /* Shifted by 1 to simplify MDCTs */
54  in_map[j*n + i] = ((i*m + j*n) % len) << mdct;
55  out_map[(i*m*m_inv + j*n*n_inv) % len] = i*m + j;
56  }
57  }
58 
59  /* Change transform direction by reversing all ACs */
60  if (inv) {
61  for (int i = 0; i < m; i++) {
62  int *in = &in_map[i*n + 1]; /* Skip the DC */
63  for (int j = 0; j < ((n - 1) >> 1); j++)
64  FFSWAP(int, in[j], in[n - j - 2]);
65  }
66  }
67 
68  /* Our 15-point transform is also a compound one, so embed its input map */
69  if (n == 15) {
70  for (int k = 0; k < m; k++) {
71  int tmp[15];
72  memcpy(tmp, &in_map[k*15], 15*sizeof(*tmp));
73  for (int i = 0; i < 5; i++) {
74  for (int j = 0; j < 3; j++)
75  in_map[k*15 + i*3 + j] = tmp[(i*3 + j*5) % 15];
76  }
77  }
78  }
79 
80  return 0;
81 }
82 
84 {
85  const int m = s->m, inv = s->inv;
86 
87  if (!(s->revtab = av_malloc(m*sizeof(*s->revtab))))
88  return AVERROR(ENOMEM);
89 
90  /* Default */
91  for (int i = 0; i < m; i++) {
92  int k = -split_radix_permutation(i, m, inv) & (m - 1);
93  s->revtab[k] = i;
94  }
95 
96  return 0;
97 }
98 
100 {
101  if (!(*ctx))
102  return;
103 
104  av_free((*ctx)->pfatab);
105  av_free((*ctx)->exptab);
106  av_free((*ctx)->revtab);
107  av_free((*ctx)->tmp);
108 
109  av_freep(ctx);
110 }
111 
113  int inv, int len, const void *scale, uint64_t flags)
114 {
115  int err;
116  AVTXContext *s = av_mallocz(sizeof(*s));
117  if (!s)
118  return AVERROR(ENOMEM);
119 
120  switch (type) {
121  case AV_TX_FLOAT_FFT:
122  case AV_TX_FLOAT_MDCT:
123  if ((err = ff_tx_init_mdct_fft_float(s, tx, type, inv, len, scale, flags)))
124  goto fail;
125  break;
126  case AV_TX_DOUBLE_FFT:
127  case AV_TX_DOUBLE_MDCT:
128  if ((err = ff_tx_init_mdct_fft_double(s, tx, type, inv, len, scale, flags)))
129  goto fail;
130  break;
131  default:
132  err = AVERROR(EINVAL);
133  goto fail;
134  }
135 
136  *ctx = s;
137 
138  return 0;
139 
140 fail:
141  av_tx_uninit(&s);
142  *tx = NULL;
143  return err;
144 }
#define NULL
Definition: coverity.c:32
av_cold void av_tx_uninit(AVTXContext **ctx)
Frees a context and sets ctx to NULL, does nothing when ctx == NULL.
Definition: tx.c:99
int inv
Definition: tx_priv.h:63
int ff_tx_gen_compound_mapping(AVTXContext *s)
Definition: tx.c:32
GLint GLenum type
Definition: opengl_enc.c:104
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
static int split_radix_permutation(int i, int n, int inverse)
Definition: fft_template.c:147
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
int ff_tx_init_mdct_fft_float(AVTXContext *s, av_tx_fn *tx, enum AVTXType type, int inv, int len, const void *scale, uint64_t flags)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
void(* av_tx_fn)(AVTXContext *s, void *out, void *in, ptrdiff_t stride)
Function pointer to a function to perform the transform.
Definition: tx.h:68
AVTXType
Definition: tx.h:35
Same as AV_TX_FLOAT_FFT with a data type of AVComplexDouble.
Definition: tx.h:49
#define fail()
Definition: checkasm.h:120
Standard complex to complex FFT with sample data type AVComplexFloat.
Definition: tx.h:40
int * revtab
Definition: tx_priv.h:69
AVFormatContext * ctx
Definition: movenc.c:48
static av_always_inline int mulinv(int n, int m)
Definition: tx.c:22
#define s(width, name)
Definition: cbs_vp9.c:257
int n
Definition: avisynth_c.h:760
int * pfatab
Definition: tx_priv.h:68
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31))))#define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac){}void ff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map){AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;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);return NULL;}return ac;}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;}else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->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);return ac;}int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){int use_generic=1;int len=in->nb_samples;int p;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%d samples - audio_convert: %s to %s (dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
av_cold int av_tx_init(AVTXContext **ctx, av_tx_fn *tx, enum AVTXType type, int inv, int len, const void *scale, uint64_t flags)
Initialize a transform context with the given configuration Currently power of two lengths from 4 to ...
Definition: tx.c:112
int type
Definition: tx_priv.h:64
#define flags(name, subs,...)
Definition: cbs_av1.c:561
Standard MDCT with sample data type of float and a scale type of float.
Definition: tx.h:45
#define av_free(p)
int ff_tx_init_mdct_fft_double(AVTXContext *s, av_tx_fn *tx, enum AVTXType type, int inv, int len, const void *scale, uint64_t flags)
int len
Same as AV_TX_FLOAT_MDCT with data and scale type of double.
Definition: tx.h:53
#define av_freep(p)
#define av_always_inline
Definition: attributes.h:39
#define FFSWAP(type, a, b)
Definition: common.h:99
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
int ff_tx_gen_ptwo_revtab(AVTXContext *s)
Definition: tx.c:83
static uint8_t tmp[11]
Definition: aes_ctr.c:26