From 42fcb6c47ca2eaf50405a865ee2639fa5ebdc4c9 Mon Sep 17 00:00:00 2001
From: Rostislav Pehlivanov <atomnuker@gmail.com>
Date: Wed, 1 Feb 2017 03:13:06 +0000
Subject: [PATCH] imdct15: rename to mdct15 and add a forward transform
Handles strides (needed for Opus transients), does pre-reindexing and folding
without needing a copy.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
---
configure | 6 +--
libavcodec/Makefile | 2 +-
libavcodec/aac.h | 4 +-
libavcodec/aacdec.c | 2 +-
libavcodec/aacdec_template.c | 4 +-
libavcodec/{imdct15.c => mdct15.c} | 90 +++++++++++++++++++++++++++++++-------
libavcodec/{imdct15.h => mdct15.h} | 28 +++++++-----
libavcodec/opus_celt.c | 10 ++---
8 files changed, 105 insertions(+), 41 deletions(-)
rename libavcodec/{imdct15.c => mdct15.c} (73%)
rename libavcodec/{imdct15.h => mdct15.h} (66%)
@@ -2107,7 +2107,7 @@ CONFIG_EXTRA="
huffyuvencdsp
idctdsp
iirfilter
- imdct15
+ mdct15
intrax8
iso_media
ividsp
@@ -2349,7 +2349,7 @@ vc1dsp_select="h264chroma qpeldsp startcode"
rdft_select="fft"
# decoders / encoders
-aac_decoder_select="imdct15 mdct sinewin"
+aac_decoder_select="mdct15 mdct sinewin"
aac_fixed_decoder_select="mdct sinewin"
aac_encoder_select="audio_frame_queue iirfilter lpc mdct sinewin"
aac_latm_decoder_select="aac_decoder aac_latm_parser"
@@ -2491,7 +2491,7 @@ nellymoser_encoder_select="audio_frame_queue mdct sinewin"
nuv_decoder_select="idctdsp lzo"
on2avc_decoder_select="mdct"
opus_decoder_deps="swresample"
-opus_decoder_select="imdct15"
+opus_decoder_select="mdct15"
png_decoder_select="zlib"
png_encoder_select="llvidencdsp zlib"
prores_decoder_select="blockdsp idctdsp"
@@ -84,7 +84,7 @@ OBJS-$(CONFIG_HUFFYUVDSP) += huffyuvdsp.o
OBJS-$(CONFIG_HUFFYUVENCDSP) += huffyuvencdsp.o
OBJS-$(CONFIG_IDCTDSP) += idctdsp.o simple_idct.o jrevdct.o
OBJS-$(CONFIG_IIRFILTER) += iirfilter.o
-OBJS-$(CONFIG_IMDCT15) += imdct15.o
+OBJS-$(CONFIG_MDCT15) += mdct15.o
OBJS-$(CONFIG_INTRAX8) += intrax8.o intrax8dsp.o
OBJS-$(CONFIG_IVIDSP) += ivi_dsp.o
OBJS-$(CONFIG_JNI) += ffjni.o jni.o
@@ -36,7 +36,7 @@
#include "libavutil/fixed_dsp.h"
#include "avcodec.h"
#if !USE_FIXED
-#include "imdct15.h"
+#include "mdct15.h"
#endif
#include "fft.h"
#include "mpeg4audio.h"
@@ -327,7 +327,7 @@ struct AACContext {
#if USE_FIXED
AVFixedDSPContext *fdsp;
#else
- IMDCT15Context *mdct480;
+ MDCT15Context *mdct480;
AVFloatDSPContext *fdsp;
#endif /* USE_FIXED */
int random_state;
@@ -42,7 +42,7 @@
#include "internal.h"
#include "get_bits.h"
#include "fft.h"
-#include "imdct15.h"
+#include "mdct15.h"
#include "lpc.h"
#include "kbdwin.h"
#include "sinewin.h"
@@ -1185,7 +1185,7 @@ static av_cold int aac_decode_init(AVCodecContext *avctx)
AAC_RENAME_32(ff_mdct_init)(&ac->mdct_small, 8, 1, 1.0 / RANGE15(128.0));
AAC_RENAME_32(ff_mdct_init)(&ac->mdct_ltp, 11, 0, RANGE15(-2.0));
#if !USE_FIXED
- ret = ff_imdct15_init(&ac->mdct480, 5);
+ ret = ff_mdct15_init(&ac->mdct480, 1, 5, -1.0f);
if (ret < 0)
return ret;
#endif
@@ -3192,7 +3192,7 @@ static av_cold int aac_decode_close(AVCodecContext *avctx)
ff_mdct_end(&ac->mdct_ld);
ff_mdct_end(&ac->mdct_ltp);
#if !USE_FIXED
- ff_imdct15_uninit(&ac->mdct480);
+ ff_mdct15_uninit(&ac->mdct480);
#endif
av_freep(&ac->fdsp);
return 0;
similarity index 73%
rename from libavcodec/imdct15.c
rename to libavcodec/mdct15.c
@@ -33,7 +33,8 @@
#include "libavutil/attributes.h"
#include "libavutil/common.h"
-#include "imdct15.h"
+#include "avfft.h"
+#include "mdct15.h"
// complex c = a * b
#define CMUL3(cre, cim, are, aim, bre, bim) \
@@ -44,9 +45,9 @@ do { \
#define CMUL(c, a, b) CMUL3((c).re, (c).im, (a).re, (a).im, (b).re, (b).im)
-av_cold void ff_imdct15_uninit(IMDCT15Context **ps)
+av_cold void ff_mdct15_uninit(MDCT15Context **ps)
{
- IMDCT15Context *s = *ps;
+ MDCT15Context *s = *ps;
if (!s)
return;
@@ -61,10 +62,12 @@ av_cold void ff_imdct15_uninit(IMDCT15Context **ps)
av_freep(ps);
}
-static void imdct15_half(IMDCT15Context *s, float *dst, const float *src,
+static void mdct15(MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride);
+
+static void imdct15_half(MDCT15Context *s, float *dst, const float *src,
ptrdiff_t stride, float scale);
-static inline int init_pfa_reindex_tabs(IMDCT15Context *s)
+static inline int init_pfa_reindex_tabs(MDCT15Context *s)
{
int i, j;
const int b_ptwo = s->ptwo_fft.nbits; /* Bits for the power of two FFTs */
@@ -85,7 +88,7 @@ static inline int init_pfa_reindex_tabs(IMDCT15Context *s)
for (j = 0; j < 15; j++) {
const int q_pre = ((l_ptwo * j)/15 + i) >> b_ptwo;
const int q_post = (((j*inv_1)/15) + (i*inv_2)) >> b_ptwo;
- const int k_pre = 15*i + (j - q_pre*15)*l_ptwo;
+ const int k_pre = 15*i + ((j - q_pre*15) << b_ptwo);
const int k_post = i*inv_2*15 + j*inv_1 - 15*q_post*l_ptwo;
s->pfa_prereindex[i*15 + j] = k_pre;
s->pfa_postreindex[k_post] = l_ptwo*j + i;
@@ -95,9 +98,10 @@ static inline int init_pfa_reindex_tabs(IMDCT15Context *s)
return 0;
}
-av_cold int ff_imdct15_init(IMDCT15Context **ps, int N)
+av_cold int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale)
{
- IMDCT15Context *s;
+ MDCT15Context *s;
+ double alpha, theta;
int len2 = 15 * (1 << N);
int len = 2 * len2;
int i;
@@ -113,9 +117,11 @@ av_cold int ff_imdct15_init(IMDCT15Context **ps, int N)
s->fft_n = N - 1;
s->len4 = len2 / 2;
s->len2 = len2;
+ s->inverse = inverse;
+ s->mdct = mdct15;
s->imdct_half = imdct15_half;
- if (ff_fft_init(&s->ptwo_fft, N - 1, 1) < 0)
+ if (ff_fft_init(&s->ptwo_fft, N - 1, s->inverse) < 0)
goto fail;
if (init_pfa_reindex_tabs(s))
@@ -129,15 +135,20 @@ av_cold int ff_imdct15_init(IMDCT15Context **ps, int N)
if (!s->twiddle_exptab)
goto fail;
+ theta = 0.125f + (scale < 0 ? s->len4 : 0);
+ scale = sqrt(fabs(scale));
for (i = 0; i < s->len4; i++) {
- s->twiddle_exptab[i].re = cos(2 * M_PI * (i + 0.125f + s->len4) / len);
- s->twiddle_exptab[i].im = sin(2 * M_PI * (i + 0.125f + s->len4) / len);
+ alpha = 2 * M_PI * (i + theta) / len;
+ s->twiddle_exptab[i].re = cos(alpha) * scale;
+ s->twiddle_exptab[i].im = sin(alpha) * scale;
}
/* 15-point FFT exptab */
for (i = 0; i < 19; i++) {
if (i < 15) {
double theta = (2.0f * M_PI * i) / 15.0f;
+ if (!s->inverse)
+ theta *= -1;
s->exptab[i].re = cos(theta);
s->exptab[i].im = sin(theta);
} else { /* Wrap around to simplify fft15 */
@@ -152,15 +163,17 @@ av_cold int ff_imdct15_init(IMDCT15Context **ps, int N)
s->exptab[20].im = sin(1.0f * M_PI / 5.0f);
/* Invert the phase for an inverse transform, do nothing for a forward transform */
- s->exptab[19].im *= -1;
- s->exptab[20].im *= -1;
+ if (s->inverse) {
+ s->exptab[19].im *= -1;
+ s->exptab[20].im *= -1;
+ }
*ps = s;
return 0;
fail:
- ff_imdct15_uninit(&s);
+ ff_mdct15_uninit(&s);
return AVERROR(ENOMEM);
}
@@ -211,8 +224,7 @@ static inline void fft5(const FFTComplex exptab[2], FFTComplex *out,
out[4].im = in[0].im + z0[3].im;
}
-static inline void fft15(const FFTComplex exptab[22], FFTComplex *out,
- const FFTComplex *in, size_t stride)
+static void fft15(const FFTComplex exptab[22], FFTComplex *out, const FFTComplex *in, size_t stride)
{
int k;
FFTComplex tmp1[5], tmp2[5], tmp3[5];
@@ -241,7 +253,51 @@ static inline void fft15(const FFTComplex exptab[22], FFTComplex *out,
}
}
-static void imdct15_half(IMDCT15Context *s, float *dst, const float *src,
+static void mdct15(MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride)
+{
+ int i, j;
+ const int len4 = s->len4, len3 = len4 * 3, len8 = len4 >> 1;
+ const int l_ptwo = 1 << s->ptwo_fft.nbits;
+ FFTComplex fft15in[15];
+
+ /* Folding and pre-reindexing */
+ for (i = 0; i < l_ptwo; i++) {
+ for (j = 0; j < 15; j++) {
+ float re, im;
+ const int k = s->pfa_prereindex[i*15 + j];
+ if (k < len8) {
+ re = -src[2*k+len3] - src[len3-1-2*k];
+ im = -src[len4+2*k] + src[len4-1-2*k];
+ } else {
+ re = src[2*k-len4] - src[1*len3-1-2*k];
+ im = -src[2*k+len4] - src[5*len4-1-2*k];
+ }
+ CMUL3(fft15in[j].re, fft15in[j].im, re, im, s->twiddle_exptab[k].re, -s->twiddle_exptab[k].im);
+ }
+ fft15(s->exptab, s->tmp + s->ptwo_fft.revtab[i], fft15in, l_ptwo);
+ }
+
+ /* Then a 15xN FFT (where N is a power of two) */
+ for (i = 0; i < 15; i++)
+ s->ptwo_fft.fft_calc(&s->ptwo_fft, s->tmp + l_ptwo*i);
+
+ /* Reindex again, apply twiddles and output */
+ for (i = 0; i < len8; i++) {
+ float re0, im0, re1, im1;
+ const int i0 = len8 + i, i1 = len8 - i - 1;
+ const int s0 = s->pfa_postreindex[i0], s1 = s->pfa_postreindex[i1];
+
+ CMUL3(im1, re0, s->tmp[s1].re, s->tmp[s1].im, s->twiddle_exptab[i1].im, s->twiddle_exptab[i1].re);
+ CMUL3(im0, re1, s->tmp[s0].re, s->tmp[s0].im, s->twiddle_exptab[i0].im, s->twiddle_exptab[i0].re);
+
+ dst[2*i1*stride ] = re0;
+ dst[2*i1*stride + stride] = im0;
+ dst[2*i0*stride ] = re1;
+ dst[2*i0*stride + stride] = im1;
+ }
+}
+
+static void imdct15_half(MDCT15Context *s, float *dst, const float *src,
ptrdiff_t stride, float scale)
{
FFTComplex fft15in[15];
similarity index 66%
rename from libavcodec/imdct15.h
rename to libavcodec/mdct15.h
@@ -1,4 +1,6 @@
/*
+ * Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.com>
+ *
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
@@ -16,17 +18,18 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#ifndef AVCODEC_IMDCT15_H
-#define AVCODEC_IMDCT15_H
+#ifndef AVCODEC_MDCT15_H
+#define AVCODEC_MDCT15_H
#include <stddef.h>
#include "fft.h"
-typedef struct IMDCT15Context {
+typedef struct MDCT15Context {
int fft_n;
int len2;
int len4;
+ int inverse;
int *pfa_prereindex;
int *pfa_postreindex;
@@ -40,20 +43,25 @@ typedef struct IMDCT15Context {
FFTComplex exptab[21];
/**
+ * Calculate a full 2N -> N MDCT
+ */
+ void (*mdct)(struct MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride);
+
+ /**
* Calculate the middle half of the iMDCT
*/
- void (*imdct_half)(struct IMDCT15Context *s, float *dst, const float *src,
+ void (*imdct_half)(struct MDCT15Context *s, float *dst, const float *src,
ptrdiff_t src_stride, float scale);
-} IMDCT15Context;
+} MDCT15Context;
/**
- * Init an iMDCT of the length 2 * 15 * (2^N)
+ * Init an (i)MDCT of the length 2 * 15 * (2^N)
*/
-int ff_imdct15_init(IMDCT15Context **s, int N);
+int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale);
/**
- * Free an iMDCT.
+ * Frees a context
*/
-void ff_imdct15_uninit(IMDCT15Context **s);
+void ff_mdct15_uninit(MDCT15Context **ps);
-#endif /* AVCODEC_IMDCT15_H */
+#endif /* AVCODEC_MDCT15_H */
@@ -29,7 +29,7 @@
#include "libavutil/float_dsp.h"
#include "libavutil/libm.h"
-#include "imdct15.h"
+#include "mdct15.h"
#include "opus.h"
#include "opustab.h"
@@ -63,7 +63,7 @@ typedef struct CeltFrame {
struct CeltContext {
// constant values that do not change during context lifetime
AVCodecContext *avctx;
- IMDCT15Context *imdct[4];
+ MDCT15Context *imdct[4];
AVFloatDSPContext *dsp;
int output_channels;
@@ -1596,7 +1596,7 @@ int ff_celt_decode_frame(CeltContext *s, OpusRangeCoder *rc,
int silence = 0;
int transient = 0;
int anticollapse = 0;
- IMDCT15Context *imdct;
+ MDCT15Context *imdct;
float imdct_scale = 1.0;
if (coded_channels != 1 && coded_channels != 2) {
@@ -1792,7 +1792,7 @@ void ff_celt_free(CeltContext **ps)
return;
for (i = 0; i < FF_ARRAY_ELEMS(s->imdct); i++)
- ff_imdct15_uninit(&s->imdct[i]);
+ ff_mdct15_uninit(&s->imdct[i]);
av_freep(&s->dsp);
av_freep(ps);
@@ -1817,7 +1817,7 @@ int ff_celt_init(AVCodecContext *avctx, CeltContext **ps, int output_channels)
s->output_channels = output_channels;
for (i = 0; i < FF_ARRAY_ELEMS(s->imdct); i++) {
- ret = ff_imdct15_init(&s->imdct[i], i + 3);
+ ret = ff_mdct15_init(&s->imdct[i], 1, i + 3, -1.0f);
if (ret < 0)
goto fail;
}
--
2.11.0.483.g087da7b7c