lavu/tx: add real to real and real to imaginary RDFT transforms

These are in-place transforms, required for DCT-I and DST-I.

Templated as the mod2 variant requires minor modifications, and is
required specifically for DCT-I/DST-I.
This commit is contained in:
Lynne 2023-08-03 18:21:23 +02:00
parent fba4546175
commit 11e22730e1
No known key found for this signature in database
GPG Key ID: A2FEA5F03F034464
5 changed files with 168 additions and 42 deletions

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@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09
API changes, most recent first:
2023-07-xx - xxxxxxxxxx - lavu 58.18.100 - tx.h
Add AV_TX_REAL_TO_REAL and AV_TX_REAL_TO_IMAGINARY
2023-08-18 - xxxxxxxxxx - lavu 58.17.100 - channel_layout.h
All AV_CHANNEL_LAYOUT_* macros are now compatible with C++ 17 and older.

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@ -437,7 +437,9 @@ int ff_tx_decompose_length(int dst[TX_MAX_DECOMPOSITIONS], enum AVTXType type,
/* Check direction for non-orthogonal codelets */
if (((cd->flags & FF_TX_FORWARD_ONLY) && inv) ||
((cd->flags & (FF_TX_INVERSE_ONLY | AV_TX_FULL_IMDCT)) && !inv))
((cd->flags & (FF_TX_INVERSE_ONLY | AV_TX_FULL_IMDCT)) && !inv) ||
((cd->flags & (FF_TX_FORWARD_ONLY | AV_TX_REAL_TO_REAL)) && inv) ||
((cd->flags & (FF_TX_FORWARD_ONLY | AV_TX_REAL_TO_IMAGINARY)) && inv))
continue;
/* Check if the CPU supports the required ISA */
@ -560,6 +562,10 @@ static void print_flags(AVBPrint *bp, uint64_t f)
av_bprintf(bp, "%spreshuf", prev > 1 ? sep : "");
if ((f & AV_TX_FULL_IMDCT) && ++prev)
av_bprintf(bp, "%simdct_full", prev > 1 ? sep : "");
if ((f & AV_TX_REAL_TO_REAL) && ++prev)
av_bprintf(bp, "%sreal_to_real", prev > 1 ? sep : "");
if ((f & AV_TX_REAL_TO_IMAGINARY) && ++prev)
av_bprintf(bp, "%sreal_to_imaginary", prev > 1 ? sep : "");
if ((f & FF_TX_ASM_CALL) && ++prev)
av_bprintf(bp, "%sasm_call", prev > 1 ? sep : "");
av_bprintf(bp, "]");
@ -717,7 +723,11 @@ av_cold int ff_tx_init_subtx(AVTXContext *s, enum AVTXType type,
uint64_t req_flags = flags;
/* Flags the codelet may require to be present */
uint64_t inv_req_mask = AV_TX_FULL_IMDCT | FF_TX_PRESHUFFLE | FF_TX_ASM_CALL;
uint64_t inv_req_mask = AV_TX_FULL_IMDCT |
AV_TX_REAL_TO_REAL |
AV_TX_REAL_TO_IMAGINARY |
FF_TX_PRESHUFFLE |
FF_TX_ASM_CALL;
/* Unaligned codelets are compatible with the aligned flag */
if (req_flags & FF_TX_ALIGNED)
@ -742,7 +752,9 @@ av_cold int ff_tx_init_subtx(AVTXContext *s, enum AVTXType type,
/* Check direction for non-orthogonal codelets */
if (((cd->flags & FF_TX_FORWARD_ONLY) && inv) ||
((cd->flags & (FF_TX_INVERSE_ONLY | AV_TX_FULL_IMDCT)) && !inv))
((cd->flags & (FF_TX_INVERSE_ONLY | AV_TX_FULL_IMDCT)) && !inv) ||
((cd->flags & (FF_TX_FORWARD_ONLY | AV_TX_REAL_TO_REAL)) && inv) ||
((cd->flags & (FF_TX_FORWARD_ONLY | AV_TX_REAL_TO_IMAGINARY)) && inv))
continue;
/* Check if the requested flags match from both sides */

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@ -149,6 +149,16 @@ enum AVTXFlags {
* Ignored for all transforms but inverse MDCTs.
*/
AV_TX_FULL_IMDCT = 1ULL << 2,
/**
* Perform a real to half-complex RDFT.
* Only the real, or imaginary coefficients will
* be output, depending on the flag used. Only available for forward RDFTs.
* Output array must have enough space to hold N complex values
* (regular size for a real to complex transform).
*/
AV_TX_REAL_TO_REAL = 1ULL << 3,
AV_TX_REAL_TO_IMAGINARY = 1ULL << 4,
};
/**

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@ -1613,14 +1613,17 @@ static av_cold int TX_NAME(ff_tx_rdft_init)(AVTXContext *s,
int ret;
double f, m;
TXSample *tab;
int len4 = FFALIGN(len, 4) / 4;
s->scale_d = *((SCALE_TYPE *)scale);
s->scale_f = s->scale_d;
flags &= ~(AV_TX_REAL_TO_REAL | AV_TX_REAL_TO_IMAGINARY);
if ((ret = ff_tx_init_subtx(s, TX_TYPE(FFT), flags, NULL, len >> 1, inv, scale)))
return ret;
if (!(s->exp = av_mallocz((8 + (len >> 2) - 1)*sizeof(*s->exp))))
if (!(s->exp = av_mallocz((8 + 2*len4)*sizeof(*s->exp))))
return AVERROR(ENOMEM);
tab = (TXSample *)s->exp;
@ -1639,17 +1642,20 @@ static av_cold int TX_NAME(ff_tx_rdft_init)(AVTXContext *s,
*tab++ = RESCALE( (0.5 - inv) * m);
*tab++ = RESCALE(-(0.5 - inv) * m);
for (int i = 0; i < len >> 2; i++)
for (int i = 0; i < len4; i++)
*tab++ = RESCALE(cos(i*f));
for (int i = len >> 2; i >= 0; i--)
*tab++ = RESCALE(cos(i*f) * (inv ? +1.0 : -1.0));
tab = ((TXSample *)s->exp) + len4 + 8;
for (int i = 0; i < len4; i++)
*tab++ = RESCALE(cos(((float)len/4.0 - (float)i + 0)*f) * (inv ? +1.0 : -1.0));
return 0;
}
#define DECL_RDFT(name, inv) \
static void TX_NAME(ff_tx_rdft_ ##name)(AVTXContext *s, void *_dst, \
void *_src, ptrdiff_t stride) \
#define DECL_RDFT(n, inv) \
static void TX_NAME(ff_tx_rdft_ ##n)(AVTXContext *s, void *_dst, \
void *_src, ptrdiff_t stride) \
{ \
const int len2 = s->len >> 1; \
const int len4 = s->len >> 2; \
@ -1698,41 +1704,132 @@ static void TX_NAME(ff_tx_rdft_ ##name)(AVTXContext *s, void *_dst, \
data[len2].re = data[0].im; \
data[ 0].im = data[len2].im = 0; \
} \
}
DECL_RDFT(r2c, 0)
DECL_RDFT(c2r, 1)
static const FFTXCodelet TX_NAME(ff_tx_rdft_r2c_def) = {
.name = TX_NAME_STR("rdft_r2c"),
.function = TX_NAME(ff_tx_rdft_r2c),
.type = TX_TYPE(RDFT),
.flags = AV_TX_UNALIGNED | AV_TX_INPLACE |
FF_TX_OUT_OF_PLACE | FF_TX_FORWARD_ONLY,
.factors = { 2, TX_FACTOR_ANY },
.nb_factors = 2,
.min_len = 2,
.max_len = TX_LEN_UNLIMITED,
.init = TX_NAME(ff_tx_rdft_init),
.cpu_flags = FF_TX_CPU_FLAGS_ALL,
.prio = FF_TX_PRIO_BASE,
} \
\
static const FFTXCodelet TX_NAME(ff_tx_rdft_ ##n## _def) = { \
.name = TX_NAME_STR("rdft_" #n), \
.function = TX_NAME(ff_tx_rdft_ ##n), \
.type = TX_TYPE(RDFT), \
.flags = AV_TX_UNALIGNED | AV_TX_INPLACE | FF_TX_OUT_OF_PLACE | \
(inv ? FF_TX_INVERSE_ONLY : FF_TX_FORWARD_ONLY), \
.factors = { 4, TX_FACTOR_ANY }, \
.nb_factors = 2, \
.min_len = 4, \
.max_len = TX_LEN_UNLIMITED, \
.init = TX_NAME(ff_tx_rdft_init), \
.cpu_flags = FF_TX_CPU_FLAGS_ALL, \
.prio = FF_TX_PRIO_BASE, \
};
static const FFTXCodelet TX_NAME(ff_tx_rdft_c2r_def) = {
.name = TX_NAME_STR("rdft_c2r"),
.function = TX_NAME(ff_tx_rdft_c2r),
.type = TX_TYPE(RDFT),
.flags = AV_TX_UNALIGNED | AV_TX_INPLACE |
FF_TX_OUT_OF_PLACE | FF_TX_INVERSE_ONLY,
.factors = { 2, TX_FACTOR_ANY },
.nb_factors = 2,
.min_len = 2,
.max_len = TX_LEN_UNLIMITED,
.init = TX_NAME(ff_tx_rdft_init),
.cpu_flags = FF_TX_CPU_FLAGS_ALL,
.prio = FF_TX_PRIO_BASE,
DECL_RDFT(r2c, 0)
DECL_RDFT(c2r, 1)
#define DECL_RDFT_HALF(n, mode, mod2) \
static void TX_NAME(ff_tx_rdft_ ##n)(AVTXContext *s, void *_dst, \
void *_src, ptrdiff_t stride) \
{ \
const int len = s->len; \
const int len2 = len >> 1; \
const int len4 = len >> 2; \
const int aligned_len4 = FFALIGN(len, 4)/4; \
const TXSample *fact = (void *)s->exp; \
const TXSample *tcos = fact + 8; \
const TXSample *tsin = tcos + aligned_len4; \
TXComplex *data = _dst; \
TXSample *out = _dst; /* Half-complex is forward-only */ \
TXSample tmp_dc; \
av_unused TXSample tmp_mid; \
TXSample tmp[4]; \
TXComplex sf, sl; \
\
s->fn[0](&s->sub[0], _dst, _src, sizeof(TXComplex)); \
\
tmp_dc = data[0].re; \
data[ 0].re = tmp_dc + data[0].im; \
tmp_dc = tmp_dc - data[0].im; \
\
data[ 0].re = MULT(fact[0], data[ 0].re); \
tmp_dc = MULT(fact[1], tmp_dc); \
data[len4].re = MULT(fact[2], data[len4].re); \
\
if (!mod2) { \
data[len4].im = MULT(fact[3], data[len4].im); \
} else { \
sf = data[len4]; \
sl = data[len4 + 1]; \
if (mode == AV_TX_REAL_TO_REAL) \
tmp[0] = MULT(fact[4], (sf.re + sl.re)); \
else \
tmp[0] = MULT(fact[5], (sf.im - sl.im)); \
tmp[1] = MULT(fact[6], (sf.im + sl.im)); \
tmp[2] = MULT(fact[7], (sf.re - sl.re)); \
\
if (mode == AV_TX_REAL_TO_REAL) { \
tmp[3] = tmp[1]*tcos[len4] - tmp[2]*tsin[len4]; \
tmp_mid = (tmp[0] - tmp[3]); \
} else { \
tmp[3] = tmp[1]*tsin[len4] + tmp[2]*tcos[len4]; \
tmp_mid = (tmp[0] + tmp[3]); \
} \
} \
\
/* NOTE: unrolling this breaks non-mod8 lengths */ \
for (int i = 1; i <= len4; i++) { \
TXSample tmp[4]; \
TXComplex sf = data[i]; \
TXComplex sl = data[len2 - i]; \
\
if (mode == AV_TX_REAL_TO_REAL) \
tmp[0] = MULT(fact[4], (sf.re + sl.re)); \
else \
tmp[0] = MULT(fact[5], (sf.im - sl.im)); \
\
tmp[1] = MULT(fact[6], (sf.im + sl.im)); \
tmp[2] = MULT(fact[7], (sf.re - sl.re)); \
\
if (mode == AV_TX_REAL_TO_REAL) { \
tmp[3] = tmp[1]*tcos[i] - tmp[2]*tsin[i]; \
out[i] = (tmp[0] + tmp[3]); \
out[len - i] = (tmp[0] - tmp[3]); \
} else { \
tmp[3] = tmp[1]*tsin[i] + tmp[2]*tcos[i]; \
out[i - 1] = (tmp[3] - tmp[0]); \
out[len - i - 1] = (tmp[0] + tmp[3]); \
} \
} \
\
for (int i = 1; i < (len4 + (mode == AV_TX_REAL_TO_IMAGINARY)); i++) \
out[len2 - i] = out[len - i]; \
\
if (mode == AV_TX_REAL_TO_REAL) { \
out[len2] = tmp_dc; \
if (mod2) \
out[len4 + 1] = tmp_mid; \
} else if (mod2) { \
out[len4] = tmp_mid; \
} \
} \
\
static const FFTXCodelet TX_NAME(ff_tx_rdft_ ##n## _def) = { \
.name = TX_NAME_STR("rdft_" #n), \
.function = TX_NAME(ff_tx_rdft_ ##n), \
.type = TX_TYPE(RDFT), \
.flags = AV_TX_UNALIGNED | AV_TX_INPLACE | mode | \
FF_TX_OUT_OF_PLACE | FF_TX_FORWARD_ONLY, \
.factors = { 2 + 2*(!mod2), TX_FACTOR_ANY }, \
.nb_factors = 2, \
.min_len = 2 + 2*(!mod2), \
.max_len = TX_LEN_UNLIMITED, \
.init = TX_NAME(ff_tx_rdft_init), \
.cpu_flags = FF_TX_CPU_FLAGS_ALL, \
.prio = FF_TX_PRIO_BASE, \
};
DECL_RDFT_HALF(r2r, AV_TX_REAL_TO_REAL, 0)
DECL_RDFT_HALF(r2r_mod2, AV_TX_REAL_TO_REAL, 1)
DECL_RDFT_HALF(r2i, AV_TX_REAL_TO_IMAGINARY, 0)
DECL_RDFT_HALF(r2i_mod2, AV_TX_REAL_TO_IMAGINARY, 1)
static av_cold int TX_NAME(ff_tx_dct_init)(AVTXContext *s,
const FFTXCodelet *cd,
uint64_t flags,
@ -1997,6 +2094,10 @@ const FFTXCodelet * const TX_NAME(ff_tx_codelet_list)[] = {
&TX_NAME(ff_tx_mdct_naive_inv_def),
&TX_NAME(ff_tx_mdct_inv_full_def),
&TX_NAME(ff_tx_rdft_r2c_def),
&TX_NAME(ff_tx_rdft_r2r_def),
&TX_NAME(ff_tx_rdft_r2r_mod2_def),
&TX_NAME(ff_tx_rdft_r2i_def),
&TX_NAME(ff_tx_rdft_r2i_mod2_def),
&TX_NAME(ff_tx_rdft_c2r_def),
&TX_NAME(ff_tx_dctII_def),
&TX_NAME(ff_tx_dctIII_def),

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@ -79,7 +79,7 @@
*/
#define LIBAVUTIL_VERSION_MAJOR 58
#define LIBAVUTIL_VERSION_MINOR 17
#define LIBAVUTIL_VERSION_MINOR 18
#define LIBAVUTIL_VERSION_MICRO 100
#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \