From 11e22730e1eb7ec6b5953c16b3b4df58be14e2de Mon Sep 17 00:00:00 2001 From: Lynne Date: Thu, 3 Aug 2023 18:21:23 +0200 Subject: [PATCH] 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. --- doc/APIchanges | 3 + libavutil/tx.c | 18 +++- libavutil/tx.h | 10 +++ libavutil/tx_template.c | 177 +++++++++++++++++++++++++++++++--------- libavutil/version.h | 2 +- 5 files changed, 168 insertions(+), 42 deletions(-) diff --git a/doc/APIchanges b/doc/APIchanges index ad1efe708d..db3242b667 100644 --- a/doc/APIchanges +++ b/doc/APIchanges @@ -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. diff --git a/libavutil/tx.c b/libavutil/tx.c index e25abf998f..e9826e6107 100644 --- a/libavutil/tx.c +++ b/libavutil/tx.c @@ -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 */ diff --git a/libavutil/tx.h b/libavutil/tx.h index 064edbc097..d178e8ee9d 100644 --- a/libavutil/tx.h +++ b/libavutil/tx.h @@ -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, }; /** diff --git a/libavutil/tx_template.c b/libavutil/tx_template.c index c4ec9502e0..c56dcf0826 100644 --- a/libavutil/tx_template.c +++ b/libavutil/tx_template.c @@ -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), diff --git a/libavutil/version.h b/libavutil/version.h index bc43baca9f..6d27f91cce 100644 --- a/libavutil/version.h +++ b/libavutil/version.h @@ -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, \