35 # define RSCALE(x) (x)
37 # define RSCALE(x) ((x) >> 1)
49 memset(s, 0,
sizeof(*s));
76 theta = 1.0 / 8.0 + (scale < 0 ? n4 : 0);
77 scale = sqrt(fabs(scale));
79 alpha = 2 * M_PI * (i + theta) / n;
80 s->
tcos[i*tstep] =
FIX15(-cos(alpha) * scale);
81 s->
tsin[i*tstep] =
FIX15(-sin(alpha) * scale);
97 int k, n8, n4, n2, n, j;
98 const uint16_t *revtab = s->
revtab;
111 in2 = input + n2 - 1;
112 for(k = 0; k < n4; k++) {
114 CMUL(z[j].
re, z[j].
im, *in2, *in1, tcos[k], tsin[k]);
121 for(k = 0; k < n8; k++) {
123 CMUL(r0, i1, z[n8-k-1].
im, z[n8-k-1].
re, tsin[n8-k-1], tcos[n8-k-1]);
124 CMUL(r1, i0, z[n8+k ].
im, z[n8+k ].
re, tsin[n8+k ], tcos[n8+k ]);
146 for(k = 0; k < n4; k++) {
147 output[k] = -output[n2-k-1];
148 output[n-k-1] = output[n2+k];
159 int i, j, n, n8, n4, n2, n3;
161 const uint16_t *revtab = s->
revtab;
174 re =
RSCALE(-input[2*i+n3] - input[n3-1-2*i]);
175 im =
RSCALE(-input[n4+2*i] + input[n4-1-2*i]);
177 CMUL(x[j].re, x[j].im, re, im, -tcos[i], tsin[i]);
179 re =
RSCALE( input[2*i] - input[n2-1-2*i]);
180 im =
RSCALE(-input[n2+2*i] - input[ n-1-2*i]);
182 CMUL(x[j].re, x[j].im, re, im, -tcos[n8 + i], tsin[n8 + i]);
190 CMUL(i1, r0, x[n8-i-1].re, x[n8-i-1].im, -tsin[n8-i-1], -tcos[n8-i-1]);
191 CMUL(i0, r1, x[n8+i ].re, x[n8+i ].im, -tsin[n8+i ], -tcos[n8+i ]);
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
av_cold int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale)
init MDCT or IMDCT computation.
void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input)
Compute the middle half of the inverse MDCT of size N = 2^nbits, thus excluding the parts that can be...
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
#define FF_MDCT_PERM_NONE
#define CMUL(dre, dim, are, aim, bre, bim)
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=av_sample_fmt_is_planar(in_fmt);out_planar=av_sample_fmt_is_planar(out_fmt);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_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_dlog(ac->avr,"%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-> out
void ff_mdct_calc_c(FFTContext *s, FFTSample *out, const FFTSample *input)
Compute MDCT of size N = 2^nbits.
av_cold void ff_mdct_end(FFTContext *s)
#define FF_MDCT_PERM_INTERLEAVE
static const uint16_t scale[4]
common internal and external API header
void(* fft_calc)(struct FFTContext *s, FFTComplex *z)
Do a complex FFT with the parameters defined in ff_fft_init().
static uint32_t inverse(uint32_t v)
find multiplicative inverse modulo 2 ^ 32
void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input)
Compute inverse MDCT of size N = 2^nbits.