Replace RD modeling with a fixed point approximation.

Change-Id: I44eb44eb3f36c05d916ef140ef42cc84f72f99ec
This commit is contained in:
Alex Converse
2014-01-03 13:24:11 -08:00
parent fdad4fd226
commit f2ca665f1c
2 changed files with 83 additions and 67 deletions

View File

@@ -12,6 +12,7 @@
#define VP9_COMMON_VP9_SYSTEMDEPENDENT_H_ #define VP9_COMMON_VP9_SYSTEMDEPENDENT_H_
#ifdef _MSC_VER #ifdef _MSC_VER
#include <intrin.h>
#include <math.h> #include <math.h>
#define snprintf _snprintf #define snprintf _snprintf
#endif #endif
@@ -34,6 +35,16 @@ static int round(double x) {
} }
#endif #endif
static const inline int get_msb(int x) {
#ifdef _MSC_VER
int r = 0;
_BitScanReverse(&r, x);
return r;
#else
return 31 ^ __builtin_clz(x);
#endif
}
struct VP9Common; struct VP9Common;
void vp9_machine_specific_config(struct VP9Common *cm); void vp9_machine_specific_config(struct VP9Common *cm);

View File

@@ -317,26 +317,14 @@ void vp9_initialize_rd_consts(VP9_COMP *cpi) {
} }
} }
static INLINE void linear_interpolate2(double x, int ntab, int inv_step, static const int MAX_XSQ_Q10 = 245727;
const double *tab1, const double *tab2,
double *v1, double *v2) {
double y = x * inv_step;
int d = (int) y;
if (d >= ntab - 1) {
*v1 = tab1[ntab - 1];
*v2 = tab2[ntab - 1];
} else {
double a = y - d;
*v1 = tab1[d] * (1 - a) + tab1[d + 1] * a;
*v2 = tab2[d] * (1 - a) + tab2[d + 1] * a;
}
}
static void model_rd_norm(double x, double *R, double *D) { static void model_rd_norm(int xsq_q10, int *r_q10, int *d_q10) {
static const int inv_tab_step = 8;
static const int tab_size = 120;
// NOTE: The tables below must be of the same size // NOTE: The tables below must be of the same size
//
// The functions described below are sampled at the four most significant
// bits of x^2 + 8 / 256
// Normalized rate // Normalized rate
// This table models the rate for a Laplacian source // This table models the rate for a Laplacian source
// source with given variance when quantized with a uniform quantizer // source with given variance when quantized with a uniform quantizer
@@ -344,22 +332,20 @@ static void model_rd_norm(double x, double *R, double *D) {
// Rn(x) = H(sqrt(r)) + sqrt(r)*[1 + H(r)/(1 - r)], // Rn(x) = H(sqrt(r)) + sqrt(r)*[1 + H(r)/(1 - r)],
// where r = exp(-sqrt(2) * x) and x = qpstep / sqrt(variance), // where r = exp(-sqrt(2) * x) and x = qpstep / sqrt(variance),
// and H(x) is the binary entropy function. // and H(x) is the binary entropy function.
static const double rate_tab[] = { static const int rate_tab_q10[] = {
64.00, 4.944, 3.949, 3.372, 2.966, 2.655, 2.403, 2.194, 65536, 6086, 5574, 5275, 5063, 4899, 4764, 4651,
2.014, 1.858, 1.720, 1.596, 1.485, 1.384, 1.291, 1.206, 4553, 4389, 4255, 4142, 4044, 3958, 3881, 3811,
1.127, 1.054, 0.986, 0.923, 0.863, 0.808, 0.756, 0.708, 3748, 3635, 3538, 3453, 3376, 3307, 3244, 3186,
0.662, 0.619, 0.579, 0.541, 0.506, 0.473, 0.442, 0.412, 3133, 3037, 2952, 2877, 2809, 2747, 2690, 2638,
0.385, 0.359, 0.335, 0.313, 0.291, 0.272, 0.253, 0.236, 2589, 2501, 2423, 2353, 2290, 2232, 2179, 2130,
0.220, 0.204, 0.190, 0.177, 0.165, 0.153, 0.142, 0.132, 2084, 2001, 1928, 1862, 1802, 1748, 1698, 1651,
0.123, 0.114, 0.106, 0.099, 0.091, 0.085, 0.079, 0.073, 1608, 1530, 1460, 1398, 1342, 1290, 1243, 1199,
0.068, 0.063, 0.058, 0.054, 0.050, 0.047, 0.043, 0.040, 1159, 1086, 1021, 963, 911, 864, 821, 781,
0.037, 0.034, 0.032, 0.029, 0.027, 0.025, 0.023, 0.022, 745, 680, 623, 574, 530, 490, 455, 424,
0.020, 0.019, 0.017, 0.016, 0.015, 0.014, 0.013, 0.012, 395, 345, 304, 269, 239, 213, 190, 171,
0.011, 0.010, 0.009, 0.008, 0.008, 0.007, 0.007, 0.006, 154, 126, 104, 87, 73, 61, 52, 44,
0.006, 0.005, 0.005, 0.005, 0.004, 0.004, 0.004, 0.003, 38, 28, 21, 16, 12, 10, 8, 6,
0.003, 0.003, 0.003, 0.002, 0.002, 0.002, 0.002, 0.002, 5, 3, 2, 1, 1, 1, 0, 0,
0.002, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001,
0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.001, 0.000,
}; };
// Normalized distortion // Normalized distortion
// This table models the normalized distortion for a Laplacian source // This table models the normalized distortion for a Laplacian source
@@ -368,54 +354,73 @@ static void model_rd_norm(double x, double *R, double *D) {
// Dn(x) = 1 - 1/sqrt(2) * x / sinh(x/sqrt(2)) // Dn(x) = 1 - 1/sqrt(2) * x / sinh(x/sqrt(2))
// where x = qpstep / sqrt(variance) // where x = qpstep / sqrt(variance)
// Note the actual distortion is Dn * variance. // Note the actual distortion is Dn * variance.
static const double dist_tab[] = { static const int dist_tab_q10[] = {
0.000, 0.001, 0.005, 0.012, 0.021, 0.032, 0.045, 0.061, 0, 0, 1, 1, 1, 2, 2, 2,
0.079, 0.098, 0.119, 0.142, 0.166, 0.190, 0.216, 0.242, 3, 3, 4, 5, 5, 6, 7, 7,
0.269, 0.296, 0.324, 0.351, 0.378, 0.405, 0.432, 0.458, 8, 9, 11, 12, 13, 15, 16, 17,
0.484, 0.509, 0.534, 0.557, 0.580, 0.603, 0.624, 0.645, 18, 21, 24, 26, 29, 31, 34, 36,
0.664, 0.683, 0.702, 0.719, 0.735, 0.751, 0.766, 0.780, 39, 44, 49, 54, 59, 64, 69, 73,
0.794, 0.807, 0.819, 0.830, 0.841, 0.851, 0.861, 0.870, 78, 88, 97, 106, 115, 124, 133, 142,
0.878, 0.886, 0.894, 0.901, 0.907, 0.913, 0.919, 0.925, 151, 167, 184, 200, 215, 231, 245, 260,
0.930, 0.935, 0.939, 0.943, 0.947, 0.951, 0.954, 0.957, 274, 301, 327, 351, 375, 397, 418, 439,
0.960, 0.963, 0.966, 0.968, 0.971, 0.973, 0.975, 0.976, 458, 495, 528, 559, 587, 613, 637, 659,
0.978, 0.980, 0.981, 0.982, 0.984, 0.985, 0.986, 0.987, 680, 717, 749, 777, 801, 823, 842, 859,
0.988, 0.989, 0.990, 0.990, 0.991, 0.992, 0.992, 0.993, 874, 899, 919, 936, 949, 960, 969, 977,
0.993, 0.994, 0.994, 0.995, 0.995, 0.996, 0.996, 0.996, 983, 994, 1001, 1006, 1010, 1013, 1015, 1017,
0.996, 0.997, 0.997, 0.997, 0.997, 0.998, 0.998, 0.998, 1018, 1020, 1022, 1022, 1023, 1023, 1023, 1024,
0.998, 0.998, 0.998, 0.999, 0.999, 0.999, 0.999, 0.999, };
0.999, 0.999, 0.999, 0.999, 0.999, 0.999, 0.999, 1.000, static const int xsq_iq_q10[] = {
0, 4, 8, 12, 16, 20, 24, 28,
32, 40, 48, 56, 64, 72, 80, 88,
96, 112, 128, 144, 160, 176, 192, 208,
224, 256, 288, 320, 352, 384, 416, 448,
480, 544, 608, 672, 736, 800, 864, 928,
992, 1120, 1248, 1376, 1504, 1632, 1760, 1888,
2016, 2272, 2528, 2784, 3040, 3296, 3552, 3808,
4064, 4576, 5088, 5600, 6112, 6624, 7136, 7648,
8160, 9184, 10208, 11232, 12256, 13280, 14304, 15328,
16352, 18400, 20448, 22496, 24544, 26592, 28640, 30688,
32736, 36832, 40928, 45024, 49120, 53216, 57312, 61408,
65504, 73696, 81888, 90080, 98272, 106464, 114656, 122848,
131040, 147424, 163808, 180192, 196576, 212960, 229344, 245728,
}; };
/* /*
assert(sizeof(rate_tab) == tab_size * sizeof(rate_tab[0]); static const int tab_size = sizeof(rate_tab_q10) / sizeof(rate_tab_q10[0]);
assert(sizeof(dist_tab) == tab_size * sizeof(dist_tab[0]); assert(sizeof(dist_tab_q10) / sizeof(dist_tab_q10[0]) == tab_size);
assert(sizeof(rate_tab) == sizeof(dist_tab)); assert(sizeof(xsq_iq_q10) / sizeof(xsq_iq_q10[0]) == tab_size);
assert(MAX_XSQ_Q10 + 1 == xsq_iq_q10[tab_size - 1]);
*/ */
assert(x >= 0.0); int tmp = (xsq_q10 >> 2) + 8;
linear_interpolate2(x, tab_size, inv_tab_step, int k = get_msb(tmp) - 3;
rate_tab, dist_tab, R, D); int xq = (k << 3) + ((tmp >> k) & 0x7);
const int one_q10 = 1 << 10;
const int a_q10 = ((xsq_q10 - xsq_iq_q10[xq]) << 10) >> (2 + k);
const int b_q10 = one_q10 - a_q10;
*r_q10 = (rate_tab_q10[xq] * b_q10 + rate_tab_q10[xq + 1] * a_q10) >> 10;
*d_q10 = (dist_tab_q10[xq] * b_q10 + dist_tab_q10[xq + 1] * a_q10) >> 10;
} }
static void model_rd_from_var_lapndz(int var, int n, int qstep, static void model_rd_from_var_lapndz(unsigned int var, unsigned int n,
int *rate, int64_t *dist) { unsigned int qstep, int *rate,
int64_t *dist) {
// This function models the rate and distortion for a Laplacian // This function models the rate and distortion for a Laplacian
// source with given variance when quantized with a uniform quantizer // source with given variance when quantized with a uniform quantizer
// with given stepsize. The closed form expressions are in: // with given stepsize. The closed form expressions are in:
// Hang and Chen, "Source Model for transform video coder and its // Hang and Chen, "Source Model for transform video coder and its
// application - Part I: Fundamental Theory", IEEE Trans. Circ. // application - Part I: Fundamental Theory", IEEE Trans. Circ.
// Sys. for Video Tech., April 1997. // Sys. for Video Tech., April 1997.
vp9_clear_system_state(); if (var == 0) {
if (var == 0 || n == 0) {
*rate = 0; *rate = 0;
*dist = 0; *dist = 0;
} else { } else {
double D, R; int d_q10, r_q10;
double s2 = (double) var / n; uint64_t xsq_q10_64 =
double x = qstep / sqrt(s2); ((((uint64_t)qstep * qstep * n) << 10) + (var >> 1)) / var;
model_rd_norm(x, &R, &D); int xsq_q10 = xsq_q10_64 > MAX_XSQ_Q10 ? MAX_XSQ_Q10 : xsq_q10_64;
*rate = (int)((n << 8) * R + 0.5); model_rd_norm(xsq_q10, &r_q10, &d_q10);
*dist = (int)(var * D + 0.5); *rate = (n * r_q10 + 2) >> 2;
*dist = (var * (int64_t)d_q10 + 512) >> 10;
} }
vp9_clear_system_state();
} }
static void model_rd_for_sb(VP9_COMP *cpi, BLOCK_SIZE bsize, static void model_rd_for_sb(VP9_COMP *cpi, BLOCK_SIZE bsize,