av1/common/daala_tx.c

#include "av1/common/daala_tx.h"
#include "av1/common/odintrin.h"

/* clang-format off */

# define OD_DCT_RSHIFT(_a, _b) OD_UNBIASED_RSHIFT32(_a, _b)

/* TODO: Daala DCT overflow checks need to be ported as a later test */
# if defined(OD_DCT_CHECK_OVERFLOW)
# else
#  define OD_DCT_OVERFLOW_CHECK(val, scale, offset, idx)
# endif

#define OD_FDCT_2_ASYM(p0, p1, p1h) \
  /* Embedded 2-point asymmetric Type-II fDCT. */ \
  do { \
    p0 += p1h; \
    p1 = p0 - p1; \
  } \
  while (0)

#define OD_IDCT_2_ASYM(p0, p1, p1h) \
  /* Embedded 2-point asymmetric Type-II iDCT. */ \
  do { \
    p1 = p0 - p1; \
    p1h = OD_DCT_RSHIFT(p1, 1); \
    p0 -= p1h; \
  } \
  while (0)

#define OD_FDST_2_ASYM(p0, p1) \
  /* Embedded 2-point asymmetric Type-IV fDST. */ \
  do { \
    /* 11507/16384 ~= 4*Sin[Pi/8] - 2*Tan[Pi/8] ~= 0.702306604714169 */ \
    OD_DCT_OVERFLOW_CHECK(p1, 11507, 8192, 187); \
    p0 -= (p1*11507 + 8192) >> 14; \
    /* 669/1024 ~= Cos[Pi/8]/Sqrt[2] ~= 0.653281482438188 */ \
    OD_DCT_OVERFLOW_CHECK(p0, 669, 512, 188); \
    p1 += (p0*669 + 512) >> 10; \
    /* 4573/4096 ~= 4*Sin[Pi/8] - Tan[Pi/8] ~= 1.11652016708726 */ \
    OD_DCT_OVERFLOW_CHECK(p1, 4573, 2048, 189); \
    p0 -= (p1*4573 + 2048) >> 12; \
  } \
  while (0)

#define OD_IDST_2_ASYM(p0, p1) \
  /* Embedded 2-point asymmetric Type-IV iDST. */ \
  do { \
    /* 4573/4096 ~= 4*Sin[Pi/8] - Tan[Pi/8] ~= 1.11652016708726 */ \
    p0 += (p1*4573 + 2048) >> 12; \
    /* 669/1024 ~= Cos[Pi/8]/Sqrt[2] ~= 0.653281482438188 */ \
    p1 -= (p0*669 + 512) >> 10; \
    /* 11507/16384 ~= 4*Sin[Pi/8] - 2*Tan[Pi/8] ~= 0.702306604714169 */ \
    p0 += (p1*11507 + 8192) >> 14; \
  } \
  while (0)

#define OD_FDCT_4(q0, q2, q1, q3) \
  /* Embedded 4-point orthonormal Type-II fDCT. */ \
  do { \
    int q2h; \
    int q3h; \
    q3 = q0 - q3; \
    q3h = OD_DCT_RSHIFT(q3, 1); \
    q0 -= q3h; \
    q2 += q1; \
    q2h = OD_DCT_RSHIFT(q2, 1); \
    q1 = q2h - q1; \
    OD_FDCT_2_ASYM(q0, q2, q2h); \
    OD_FDST_2_ASYM(q3, q1); \
  } \
  while (0)

#define OD_IDCT_4(q0, q2, q1, q3) \
  /* Embedded 4-point orthonormal Type-II iDCT. */ \
  do { \
    int q1h; \
    int q3h; \
    OD_IDST_2_ASYM(q3, q2); \
    OD_IDCT_2_ASYM(q0, q1, q1h); \
    q3h = OD_DCT_RSHIFT(q3, 1); \
    q0 += q3h; \
    q3 = q0 - q3; \
    q2 = q1h - q2; \
    q1 -= q2; \
  } \
  while (0)

void od_bin_fdct4(od_coeff y[4], const od_coeff *x, int xstride) {
  int q0;
  int q1;
  int q2;
  int q3;
  q0 = x[0*xstride];
  q2 = x[1*xstride];
  q1 = x[2*xstride];
  q3 = x[3*xstride];
  OD_FDCT_4(q0, q2, q1, q3);
  y[0] = (od_coeff)q0;
  y[1] = (od_coeff)q1;
  y[2] = (od_coeff)q2;
  y[3] = (od_coeff)q3;
}

void od_bin_idct4(od_coeff *x, int xstride, const od_coeff y[4]) {
  int q0;
  int q1;
  int q2;
  int q3;
  q0 = y[0];
  q2 = y[1];
  q1 = y[2];
  q3 = y[3];
  OD_IDCT_4(q0, q2, q1, q3);
  x[0*xstride] = q0;
  x[1*xstride] = q1;
  x[2*xstride] = q2;
  x[3*xstride] = q3;
}