FFmpeg
tx.h
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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
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17  */
18 
19 #ifndef AVUTIL_TX_H
20 #define AVUTIL_TX_H
21 
22 #include <stdint.h>
23 #include <stddef.h>
24 
25 typedef struct AVTXContext AVTXContext;
26 
27 typedef struct AVComplexFloat {
28  float re, im;
30 
31 typedef struct AVComplexDouble {
32  double re, im;
34 
35 typedef struct AVComplexInt32 {
38 
39 enum AVTXType {
40  /**
41  * Standard complex to complex FFT with sample data type AVComplexFloat.
42  * Output is not 1/len normalized. Scaling currently unsupported.
43  * The stride parameter is ignored.
44  */
46 
47  /**
48  * Standard MDCT with sample data type of float and a scale type of
49  * float. Length is the frame size, not the window size (which is 2x frame)
50  * For forward transforms, the stride specifies the spacing between each
51  * sample in the output array in bytes. The input must be a flat array.
52  * For inverse transforms, the stride specifies the spacing between each
53  * sample in the input array in bytes. The output will be a flat array.
54  * Stride must be a non-zero multiple of sizeof(float).
55  * NOTE: the inverse transform is half-length, meaning the output will not
56  * contain redundant data. This is what most codecs work with.
57  */
59 
60  /**
61  * Same as AV_TX_FLOAT_FFT with a data type of AVComplexDouble.
62  */
64 
65  /**
66  * Same as AV_TX_FLOAT_MDCT with data and scale type of double.
67  * Stride must be a non-zero multiple of sizeof(double).
68  */
70 
71  /**
72  * Same as AV_TX_FLOAT_FFT with a data type of AVComplexInt32.
73  */
75 
76  /**
77  * Same as AV_TX_FLOAT_MDCT with data type of int32_t and scale type of float.
78  * Only scale values less than or equal to 1.0 are supported.
79  * Stride must be a non-zero multiple of sizeof(int32_t).
80  */
82 };
83 
84 /**
85  * Function pointer to a function to perform the transform.
86  *
87  * @note Using a different context than the one allocated during av_tx_init()
88  * is not allowed.
89  *
90  * @param s the transform context
91  * @param out the output array
92  * @param in the input array
93  * @param stride the input or output stride in bytes
94  *
95  * The out and in arrays must be aligned to the maximum required by the CPU
96  * architecture.
97  * The stride must follow the constraints the transform type has specified.
98  */
99 typedef void (*av_tx_fn)(AVTXContext *s, void *out, void *in, ptrdiff_t stride);
100 
101 /**
102  * Flags for av_tx_init()
103  */
104 enum AVTXFlags {
105  /**
106  * Performs an in-place transformation on the input. The output argument
107  * of av_tn_fn() MUST match the input. May be unsupported or slower for some
108  * transform types.
109  */
110  AV_TX_INPLACE = 1ULL << 0,
111 };
112 
113 /**
114  * Initialize a transform context with the given configuration
115  * (i)MDCTs with an odd length are currently not supported.
116  *
117  * @param ctx the context to allocate, will be NULL on error
118  * @param tx pointer to the transform function pointer to set
119  * @param type type the type of transform
120  * @param inv whether to do an inverse or a forward transform
121  * @param len the size of the transform in samples
122  * @param scale pointer to the value to scale the output if supported by type
123  * @param flags a bitmask of AVTXFlags or 0
124  *
125  * @return 0 on success, negative error code on failure
126  */
128  int inv, int len, const void *scale, uint64_t flags);
129 
130 /**
131  * Frees a context and sets ctx to NULL, does nothing when ctx == NULL
132  */
134 
135 #endif /* AVUTIL_TX_H */
stride
int stride
Definition: mace.c:144
AV_TX_DOUBLE_MDCT
@ AV_TX_DOUBLE_MDCT
Same as AV_TX_FLOAT_MDCT with data and scale type of double.
Definition: tx.h:69
out
FILE * out
Definition: movenc.c:54
AVTXContext
Definition: tx_priv.h:108
AVComplexDouble::im
double im
Definition: tx.h:32
AV_TX_DOUBLE_FFT
@ AV_TX_DOUBLE_FFT
Same as AV_TX_FLOAT_FFT with a data type of AVComplexDouble.
Definition: tx.h:63
AVComplexFloat
Definition: tx.h:27
av_tx_init
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 (i)MDCTs with an odd length are currently...
Definition: tx.c:160
AVComplexFloat::im
float im
Definition: tx.h:28
AVComplexInt32::re
int32_t re
Definition: tx.h:36
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
av_tx_fn
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:99
AV_TX_FLOAT_MDCT
@ AV_TX_FLOAT_MDCT
Standard MDCT with sample data type of float and a scale type of float.
Definition: tx.h:58
AVComplexInt32
Definition: tx.h:35
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_TX_INT32_MDCT
@ AV_TX_INT32_MDCT
Same as AV_TX_FLOAT_MDCT with data type of int32_t and scale type of float.
Definition: tx.h:81
AV_TX_FLOAT_FFT
@ AV_TX_FLOAT_FFT
Standard complex to complex FFT with sample data type AVComplexFloat.
Definition: tx.h:45
ctx
AVFormatContext * ctx
Definition: movenc.c:48
int32_t
int32_t
Definition: audio_convert.c:194
AV_TX_INPLACE
@ AV_TX_INPLACE
Performs an in-place transformation on the input.
Definition: tx.h:110
AVTXType
AVTXType
Definition: tx.h:39
AVComplexFloat::re
float re
Definition: tx.h:28
AV_TX_INT32_FFT
@ AV_TX_INT32_FFT
Same as AV_TX_FLOAT_FFT with a data type of AVComplexInt32.
Definition: tx.h:74
AVTXFlags
AVTXFlags
Flags for av_tx_init()
Definition: tx.h:104
in
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
Definition: audio_convert.c:326
av_tx_uninit
void av_tx_uninit(AVTXContext **ctx)
Frees a context and sets ctx to NULL, does nothing when ctx == NULL.
Definition: tx.c:146
len
int len
Definition: vorbis_enc_data.h:452
AVComplexDouble
Definition: tx.h:31
AVComplexDouble::re
double re
Definition: tx.h:32
AVComplexInt32::im
int32_t im
Definition: tx.h:36
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561