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/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stddef.h>
#include <string.h>
#include "libavutil/attributes.h"
#include "libavutil/macros.h"
#include "libavutil/mem.h"
#include "libavutil/tx.h"
#include "avfft.h"
typedef struct AVTXWrapper {
AVTXContext *ctx;
av_tx_fn fn;
AVTXContext *ctx2;
av_tx_fn fn2;
ptrdiff_t stride;
int len;
int inv;
float *tmp;
int out_of_place;
} AVTXWrapper;
/* FFT */
FFTContext *av_fft_init(int nbits, int inverse)
{
int ret;
float scale = 1.0f;
AVTXWrapper *s = av_mallocz(sizeof(*s));
if (!s)
return NULL;
ret = av_tx_init(&s->ctx, &s->fn, AV_TX_FLOAT_FFT, inverse, 1 << nbits,
&scale, AV_TX_INPLACE);
if (ret < 0) {
av_free(s);
return NULL;
}
return (FFTContext *)s;
}
void av_fft_permute(FFTContext *s, FFTComplex *z)
{
/* Empty */
}
void av_fft_calc(FFTContext *s, FFTComplex *z)
{
AVTXWrapper *w = (AVTXWrapper *)s;
w->fn(w->ctx, z, (void *)z, sizeof(AVComplexFloat));
}
av_cold void av_fft_end(FFTContext *s)
{
if (s) {
AVTXWrapper *w = (AVTXWrapper *)s;
av_tx_uninit(&w->ctx);
av_tx_uninit(&w->ctx2);
av_free(w);
}
}
FFTContext *av_mdct_init(int nbits, int inverse, double scale)
{
int ret;
float scale_f = scale;
AVTXWrapper *s = av_mallocz(sizeof(*s));
if (!s)
return NULL;
ret = av_tx_init(&s->ctx, &s->fn, AV_TX_FLOAT_MDCT, inverse, 1 << (nbits - 1), &scale_f, 0);
if (ret < 0) {
av_free(s);
return NULL;
}
if (inverse) {
ret = av_tx_init(&s->ctx2, &s->fn2, AV_TX_FLOAT_MDCT, inverse, 1 << (nbits - 1),
&scale_f, AV_TX_FULL_IMDCT);
if (ret < 0) {
av_tx_uninit(&s->ctx);
av_free(s);
return NULL;
}
}
return (FFTContext *)s;
}
void av_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
{
AVTXWrapper *w = (AVTXWrapper *)s;
w->fn2(w->ctx2, output, (void *)input, sizeof(float));
}
void av_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input)
{
AVTXWrapper *w = (AVTXWrapper *)s;
w->fn(w->ctx, output, (void *)input, sizeof(float));
}
void av_mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
{
AVTXWrapper *w = (AVTXWrapper *)s;
w->fn(w->ctx, output, (void *)input, sizeof(float));
}
av_cold void av_mdct_end(FFTContext *s)
{
if (s) {
AVTXWrapper *w = (AVTXWrapper *)s;
av_tx_uninit(&w->ctx2);
av_tx_uninit(&w->ctx);
av_free(w);
}
}
RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans)
{
int ret;
float scale = trans == IDFT_C2R ? 0.5f : 1.0f;
AVTXWrapper *s;
/* The other 2 modes are unconventional, do not form an orthogonal
* transform, have never been useful, and so they're not implemented. */
if (trans != IDFT_C2R && trans != DFT_R2C)
return NULL;
s = av_mallocz(sizeof(*s));
if (!s)
return NULL;
ret = av_tx_init(&s->ctx, &s->fn, AV_TX_FLOAT_RDFT, trans == IDFT_C2R,
1 << nbits, &scale, 0x0);
if (ret < 0) {
av_free(s);
return NULL;
}
s->stride = (trans == DFT_C2R) ? sizeof(float) : sizeof(AVComplexFloat);
s->len = 1 << nbits;
s->inv = trans == IDFT_C2R;
s->tmp = av_malloc((s->len + 2)*sizeof(float));
if (!s->tmp) {
av_tx_uninit(&s->ctx);
av_free(s);
return NULL;
}
return (RDFTContext *)s;
}
void av_rdft_calc(RDFTContext *s, FFTSample *data)
{
AVTXWrapper *w = (AVTXWrapper *)s;
float *src = w->inv ? w->tmp : (float *)data;
float *dst = w->inv ? (float *)data : w->tmp;
if (w->inv) {
memcpy(src, data, w->len*sizeof(float));
src[w->len] = src[1];
src[1] = 0.0f;
}
w->fn(w->ctx, dst, (void *)src, w->stride);
if (!w->inv) {
dst[1] = dst[w->len];
memcpy(data, dst, w->len*sizeof(float));
}
}
av_cold void av_rdft_end(RDFTContext *s)
{
if (s) {
AVTXWrapper *w = (AVTXWrapper *)s;
av_tx_uninit(&w->ctx);
av_free(w->tmp);
av_free(w);
}
}
DCTContext *av_dct_init(int nbits, enum DCTTransformType inverse)
{
int ret;
const float scale_map[] = {
[DCT_II] = 0.5f,
[DCT_III] = 1.0f / (1 << nbits),
[DCT_I] = 0.5f,
[DST_I] = 2.0f,
};
static const enum AVTXType type_map[] = {
[DCT_II] = AV_TX_FLOAT_DCT,
[DCT_III] = AV_TX_FLOAT_DCT,
[DCT_I] = AV_TX_FLOAT_DCT_I,
[DST_I] = AV_TX_FLOAT_DST_I,
};
AVTXWrapper *s = av_mallocz(sizeof(*s));
if (!s)
return NULL;
s->len = (1 << nbits);
s->out_of_place = (inverse == DCT_I) || (inverse == DST_I);
ret = av_tx_init(&s->ctx, &s->fn, type_map[inverse],
(inverse == DCT_III), 1 << (nbits - (inverse == DCT_III)),
&scale_map[inverse], s->out_of_place ? 0 : AV_TX_INPLACE);
if (ret < 0) {
av_free(s);
return NULL;
}
if (s->out_of_place) {
s->tmp = av_malloc((1 << (nbits + 1))*sizeof(float));
if (!s->tmp) {
av_tx_uninit(&s->ctx);
av_free(s);
return NULL;
}
}
return (DCTContext *)s;
}
void av_dct_calc(DCTContext *s, FFTSample *data)
{
AVTXWrapper *w = (AVTXWrapper *)s;
if (w->out_of_place) {
memcpy(w->tmp, data, w->len*sizeof(float));
w->fn(w->ctx, (void *)data, w->tmp, sizeof(float));
} else {
w->fn(w->ctx, data, (void *)data, sizeof(float));
}
}
av_cold void av_dct_end(DCTContext *s)
{
if (s) {
AVTXWrapper *w = (AVTXWrapper *)s;
av_tx_uninit(&w->ctx);
av_free(w->tmp);
av_free(w);
}
}