ref: 94ecfa323f8fc5af68244a15058374a887758d5a
dir: /vp9/encoder/vp9_variance.c/
/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "./vp9_rtcd.h"
#include "vpx_ports/mem.h"
#include "vpx/vpx_integer.h"
#include "vp9/common/vp9_common.h"
#include "vp9/common/vp9_filter.h"
#include "vp9/encoder/vp9_variance.h"
void variance(const uint8_t *a, int a_stride,
const uint8_t *b, int b_stride,
int w, int h, unsigned int *sse, int *sum) {
int i, j;
*sum = 0;
*sse = 0;
for (i = 0; i < h; i++) {
for (j = 0; j < w; j++) {
const int diff = a[j] - b[j];
*sum += diff;
*sse += diff * diff;
}
a += a_stride;
b += b_stride;
}
}
// Applies a 1-D 2-tap bi-linear filter to the source block in either horizontal
// or vertical direction to produce the filtered output block. Used to implement
// first-pass of 2-D separable filter.
//
// Produces int32_t output to retain precision for next pass. Two filter taps
// should sum to VP9_FILTER_WEIGHT. pixel_step defines whether the filter is
// applied horizontally (pixel_step=1) or vertically (pixel_step=stride). It
// defines the offset required to move from one input to the next.
static void var_filter_block2d_bil_first_pass(const uint8_t *src_ptr,
uint16_t *output_ptr,
unsigned int src_pixels_per_line,
int pixel_step,
unsigned int output_height,
unsigned int output_width,
const int16_t *vp9_filter) {
unsigned int i, j;
for (i = 0; i < output_height; i++) {
for (j = 0; j < output_width; j++) {
output_ptr[j] = ROUND_POWER_OF_TWO((int)src_ptr[0] * vp9_filter[0] +
(int)src_ptr[pixel_step] * vp9_filter[1],
FILTER_BITS);
src_ptr++;
}
// Next row...
src_ptr += src_pixels_per_line - output_width;
output_ptr += output_width;
}
}
// Applies a 1-D 2-tap bi-linear filter to the source block in either horizontal
// or vertical direction to produce the filtered output block. Used to implement
// second-pass of 2-D separable filter.
//
// Requires 32-bit input as produced by filter_block2d_bil_first_pass. Two
// filter taps should sum to VP9_FILTER_WEIGHT. pixel_step defines whether the
// filter is applied horizontally (pixel_step=1) or vertically (pixel_step=
// stride). It defines the offset required to move from one input to the next.
static void var_filter_block2d_bil_second_pass(const uint16_t *src_ptr,
uint8_t *output_ptr,
unsigned int src_pixels_per_line,
unsigned int pixel_step,
unsigned int output_height,
unsigned int output_width,
const int16_t *vp9_filter) {
unsigned int i, j;
for (i = 0; i < output_height; i++) {
for (j = 0; j < output_width; j++) {
output_ptr[j] = ROUND_POWER_OF_TWO((int)src_ptr[0] * vp9_filter[0] +
(int)src_ptr[pixel_step] * vp9_filter[1],
FILTER_BITS);
src_ptr++;
}
src_ptr += src_pixels_per_line - output_width;
output_ptr += output_width;
}
}
unsigned int vp9_get_mb_ss_c(const int16_t *src_ptr) {
unsigned int i, sum = 0;
for (i = 0; i < 256; ++i) {
sum += src_ptr[i] * src_ptr[i];
}
return sum;
}
#define VAR(W, H) \
unsigned int vp9_variance##W##x##H##_c(const uint8_t *a, int a_stride, \
const uint8_t *b, int b_stride, \
unsigned int *sse) { \
int sum; \
variance(a, a_stride, b, b_stride, W, H, sse, &sum); \
return *sse - (((int64_t)sum * sum) / (W * H)); \
}
#define SUBPIX_VAR(W, H) \
unsigned int vp9_sub_pixel_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse) { \
uint16_t fdata3[(H + 1) * W]; \
uint8_t temp2[H * W]; \
\
var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, W, \
BILINEAR_FILTERS_2TAP(xoffset)); \
var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
return vp9_variance##W##x##H##_c(temp2, W, dst, dst_stride, sse); \
}
#define SUBPIX_AVG_VAR(W, H) \
unsigned int vp9_sub_pixel_avg_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse, \
const uint8_t *second_pred) { \
uint16_t fdata3[(H + 1) * W]; \
uint8_t temp2[H * W]; \
DECLARE_ALIGNED_ARRAY(16, uint8_t, temp3, H * W); \
\
var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, W, \
BILINEAR_FILTERS_2TAP(xoffset)); \
var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
vp9_comp_avg_pred(temp3, second_pred, W, H, temp2, W); \
\
return vp9_variance##W##x##H##_c(temp3, W, dst, dst_stride, sse); \
}
void vp9_get16x16var_c(const uint8_t *src_ptr, int source_stride,
const uint8_t *ref_ptr, int ref_stride,
unsigned int *sse, int *sum) {
variance(src_ptr, source_stride, ref_ptr, ref_stride, 16, 16, sse, sum);
}
void vp9_get8x8var_c(const uint8_t *src_ptr, int source_stride,
const uint8_t *ref_ptr, int ref_stride,
unsigned int *sse, int *sum) {
variance(src_ptr, source_stride, ref_ptr, ref_stride, 8, 8, sse, sum);
}
unsigned int vp9_mse16x16_c(const uint8_t *src, int src_stride,
const uint8_t *ref, int ref_stride,
unsigned int *sse) {
int sum;
variance(src, src_stride, ref, ref_stride, 16, 16, sse, &sum);
return *sse;
}
unsigned int vp9_mse16x8_c(const uint8_t *src, int src_stride,
const uint8_t *ref, int ref_stride,
unsigned int *sse) {
int sum;
variance(src, src_stride, ref, ref_stride, 16, 8, sse, &sum);
return *sse;
}
unsigned int vp9_mse8x16_c(const uint8_t *src, int src_stride,
const uint8_t *ref, int ref_stride,
unsigned int *sse) {
int sum;
variance(src, src_stride, ref, ref_stride, 8, 16, sse, &sum);
return *sse;
}
unsigned int vp9_mse8x8_c(const uint8_t *src, int src_stride,
const uint8_t *ref, int ref_stride,
unsigned int *sse) {
int sum;
variance(src, src_stride, ref, ref_stride, 8, 8, sse, &sum);
return *sse;
}
VAR(4, 4)
SUBPIX_VAR(4, 4)
SUBPIX_AVG_VAR(4, 4)
VAR(4, 8)
SUBPIX_VAR(4, 8)
SUBPIX_AVG_VAR(4, 8)
VAR(8, 4)
SUBPIX_VAR(8, 4)
SUBPIX_AVG_VAR(8, 4)
VAR(8, 8)
SUBPIX_VAR(8, 8)
SUBPIX_AVG_VAR(8, 8)
VAR(8, 16)
SUBPIX_VAR(8, 16)
SUBPIX_AVG_VAR(8, 16)
VAR(16, 8)
SUBPIX_VAR(16, 8)
SUBPIX_AVG_VAR(16, 8)
VAR(16, 16)
SUBPIX_VAR(16, 16)
SUBPIX_AVG_VAR(16, 16)
VAR(16, 32)
SUBPIX_VAR(16, 32)
SUBPIX_AVG_VAR(16, 32)
VAR(32, 16)
SUBPIX_VAR(32, 16)
SUBPIX_AVG_VAR(32, 16)
VAR(32, 32)
SUBPIX_VAR(32, 32)
SUBPIX_AVG_VAR(32, 32)
VAR(32, 64)
SUBPIX_VAR(32, 64)
SUBPIX_AVG_VAR(32, 64)
VAR(64, 32)
SUBPIX_VAR(64, 32)
SUBPIX_AVG_VAR(64, 32)
VAR(64, 64)
SUBPIX_VAR(64, 64)
SUBPIX_AVG_VAR(64, 64)
void vp9_comp_avg_pred(uint8_t *comp_pred, const uint8_t *pred, int width,
int height, const uint8_t *ref, int ref_stride) {
int i, j;
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
const int tmp = pred[j] + ref[j];
comp_pred[j] = ROUND_POWER_OF_TWO(tmp, 1);
}
comp_pred += width;
pred += width;
ref += ref_stride;
}
}
#if CONFIG_VP9_HIGHBITDEPTH
void highbd_variance64(const uint8_t *a8, int a_stride,
const uint8_t *b8, int b_stride,
int w, int h, uint64_t *sse,
uint64_t *sum) {
int i, j;
uint16_t *a = CONVERT_TO_SHORTPTR(a8);
uint16_t *b = CONVERT_TO_SHORTPTR(b8);
*sum = 0;
*sse = 0;
for (i = 0; i < h; i++) {
for (j = 0; j < w; j++) {
const int diff = a[j] - b[j];
*sum += diff;
*sse += diff * diff;
}
a += a_stride;
b += b_stride;
}
}
void highbd_variance(const uint8_t *a8, int a_stride,
const uint8_t *b8, int b_stride,
int w, int h, unsigned int *sse,
int *sum) {
uint64_t sse_long = 0;
uint64_t sum_long = 0;
highbd_variance64(a8, a_stride, b8, b_stride, w, h, &sse_long, &sum_long);
*sse = sse_long;
*sum = sum_long;
}
void highbd_10_variance(const uint8_t *a8, int a_stride,
const uint8_t *b8, int b_stride,
int w, int h, unsigned int *sse,
int *sum) {
uint64_t sse_long = 0;
uint64_t sum_long = 0;
highbd_variance64(a8, a_stride, b8, b_stride, w, h, &sse_long, &sum_long);
*sum = ROUND_POWER_OF_TWO(sum_long, 2);
*sse = ROUND_POWER_OF_TWO(sse_long, 4);
}
void highbd_12_variance(const uint8_t *a8, int a_stride,
const uint8_t *b8, int b_stride,
int w, int h, unsigned int *sse,
int *sum) {
uint64_t sse_long = 0;
uint64_t sum_long = 0;
highbd_variance64(a8, a_stride, b8, b_stride, w, h, &sse_long, &sum_long);
*sum = ROUND_POWER_OF_TWO(sum_long, 4);
*sse = ROUND_POWER_OF_TWO(sse_long, 8);
}
static void highbd_var_filter_block2d_bil_first_pass(
const uint8_t *src_ptr8,
uint16_t *output_ptr,
unsigned int src_pixels_per_line,
int pixel_step,
unsigned int output_height,
unsigned int output_width,
const int16_t *vp9_filter) {
unsigned int i, j;
uint16_t *src_ptr = CONVERT_TO_SHORTPTR(src_ptr8);
for (i = 0; i < output_height; i++) {
for (j = 0; j < output_width; j++) {
output_ptr[j] =
ROUND_POWER_OF_TWO((int)src_ptr[0] * vp9_filter[0] +
(int)src_ptr[pixel_step] * vp9_filter[1],
FILTER_BITS);
src_ptr++;
}
// Next row...
src_ptr += src_pixels_per_line - output_width;
output_ptr += output_width;
}
}
static void highbd_var_filter_block2d_bil_second_pass(
const uint16_t *src_ptr,
uint16_t *output_ptr,
unsigned int src_pixels_per_line,
unsigned int pixel_step,
unsigned int output_height,
unsigned int output_width,
const int16_t *vp9_filter) {
unsigned int i, j;
for (i = 0; i < output_height; i++) {
for (j = 0; j < output_width; j++) {
output_ptr[j] =
ROUND_POWER_OF_TWO((int)src_ptr[0] * vp9_filter[0] +
(int)src_ptr[pixel_step] * vp9_filter[1],
FILTER_BITS);
src_ptr++;
}
src_ptr += src_pixels_per_line - output_width;
output_ptr += output_width;
}
}
#define HIGHBD_VAR(W, H) \
unsigned int vp9_highbd_variance##W##x##H##_c(const uint8_t *a, int a_stride, \
const uint8_t *b, int b_stride, \
unsigned int *sse) { \
int sum; \
highbd_variance(a, a_stride, b, b_stride, W, H, sse, &sum); \
return *sse - (((int64_t)sum * sum) / (W * H)); \
} \
\
unsigned int vp9_highbd_10_variance##W##x##H##_c(const uint8_t *a, \
int a_stride, \
const uint8_t *b, \
int b_stride, \
unsigned int *sse) { \
int sum; \
highbd_10_variance(a, a_stride, b, b_stride, W, H, sse, &sum); \
return *sse - (((int64_t)sum * sum) / (W * H)); \
} \
\
unsigned int vp9_highbd_12_variance##W##x##H##_c(const uint8_t *a, \
int a_stride, \
const uint8_t *b, \
int b_stride, \
unsigned int *sse) { \
int sum; \
highbd_12_variance(a, a_stride, b, b_stride, W, H, sse, &sum); \
return *sse - (((int64_t)sum * sum) / (W * H)); \
}
#define HIGHBD_SUBPIX_VAR(W, H) \
unsigned int vp9_highbd_sub_pixel_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse) { \
uint16_t fdata3[(H + 1) * W]; \
uint16_t temp2[H * W]; \
\
highbd_var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, \
W, BILINEAR_FILTERS_2TAP(xoffset)); \
highbd_var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
return vp9_highbd_variance##W##x##H##_c(CONVERT_TO_BYTEPTR(temp2), W, dst, \
dst_stride, sse); \
} \
\
unsigned int vp9_highbd_10_sub_pixel_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse) { \
uint16_t fdata3[(H + 1) * W]; \
uint16_t temp2[H * W]; \
\
highbd_var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, \
W, BILINEAR_FILTERS_2TAP(xoffset)); \
highbd_var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
return vp9_highbd_10_variance##W##x##H##_c(CONVERT_TO_BYTEPTR(temp2), \
W, dst, dst_stride, sse); \
} \
\
unsigned int vp9_highbd_12_sub_pixel_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse) { \
uint16_t fdata3[(H + 1) * W]; \
uint16_t temp2[H * W]; \
\
highbd_var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, \
W, BILINEAR_FILTERS_2TAP(xoffset)); \
highbd_var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
return vp9_highbd_12_variance##W##x##H##_c(CONVERT_TO_BYTEPTR(temp2), \
W, dst, dst_stride, sse); \
}
#define HIGHBD_SUBPIX_AVG_VAR(W, H) \
unsigned int vp9_highbd_sub_pixel_avg_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse, \
const uint8_t *second_pred) { \
uint16_t fdata3[(H + 1) * W]; \
uint16_t temp2[H * W]; \
DECLARE_ALIGNED_ARRAY(16, uint16_t, temp3, H * W); \
\
highbd_var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, \
W, BILINEAR_FILTERS_2TAP(xoffset)); \
highbd_var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
vp9_highbd_comp_avg_pred(temp3, second_pred, W, H, \
CONVERT_TO_BYTEPTR(temp2), W); \
\
return vp9_highbd_variance##W##x##H##_c(CONVERT_TO_BYTEPTR(temp3), W, dst, \
dst_stride, sse); \
} \
\
unsigned int vp9_highbd_10_sub_pixel_avg_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse, \
const uint8_t *second_pred) { \
uint16_t fdata3[(H + 1) * W]; \
uint16_t temp2[H * W]; \
DECLARE_ALIGNED_ARRAY(16, uint16_t, temp3, H * W); \
\
highbd_var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, \
W, BILINEAR_FILTERS_2TAP(xoffset)); \
highbd_var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
vp9_highbd_comp_avg_pred(temp3, second_pred, W, H, \
CONVERT_TO_BYTEPTR(temp2), W); \
\
return vp9_highbd_10_variance##W##x##H##_c(CONVERT_TO_BYTEPTR(temp3), \
W, dst, dst_stride, sse); \
} \
\
unsigned int vp9_highbd_12_sub_pixel_avg_variance##W##x##H##_c( \
const uint8_t *src, int src_stride, \
int xoffset, int yoffset, \
const uint8_t *dst, int dst_stride, \
unsigned int *sse, \
const uint8_t *second_pred) { \
uint16_t fdata3[(H + 1) * W]; \
uint16_t temp2[H * W]; \
DECLARE_ALIGNED_ARRAY(16, uint16_t, temp3, H * W); \
\
highbd_var_filter_block2d_bil_first_pass(src, fdata3, src_stride, 1, H + 1, \
W, BILINEAR_FILTERS_2TAP(xoffset)); \
highbd_var_filter_block2d_bil_second_pass(fdata3, temp2, W, W, H, W, \
BILINEAR_FILTERS_2TAP(yoffset)); \
\
vp9_highbd_comp_avg_pred(temp3, second_pred, W, H, \
CONVERT_TO_BYTEPTR(temp2), W); \
\
return vp9_highbd_12_variance##W##x##H##_c(CONVERT_TO_BYTEPTR(temp3), \
W, dst, dst_stride, sse); \
}
#define HIGHBD_GET_VAR(S) \
void vp9_highbd_get##S##x##S##var_c(const uint8_t *src, int src_stride, \
const uint8_t *ref, int ref_stride, \
unsigned int *sse, int *sum) { \
highbd_variance(src, src_stride, ref, ref_stride, S, S, sse, sum); \
} \
\
void vp9_highbd_10_get##S##x##S##var_c(const uint8_t *src, int src_stride, \
const uint8_t *ref, int ref_stride, \
unsigned int *sse, int *sum) { \
highbd_10_variance(src, src_stride, ref, ref_stride, S, S, sse, sum); \
} \
\
void vp9_highbd_12_get##S##x##S##var_c(const uint8_t *src, int src_stride, \
const uint8_t *ref, int ref_stride, \
unsigned int *sse, int *sum) { \
highbd_12_variance(src, src_stride, ref, ref_stride, S, S, sse, sum); \
}
#define HIGHBD_MSE(W, H) \
unsigned int vp9_highbd_mse##W##x##H##_c(const uint8_t *src, \
int src_stride, \
const uint8_t *ref, \
int ref_stride, \
unsigned int *sse) { \
int sum; \
highbd_variance(src, src_stride, ref, ref_stride, W, H, sse, &sum); \
return *sse; \
} \
\
unsigned int vp9_highbd_10_mse##W##x##H##_c(const uint8_t *src, \
int src_stride, \
const uint8_t *ref, \
int ref_stride, \
unsigned int *sse) { \
int sum; \
highbd_10_variance(src, src_stride, ref, ref_stride, W, H, sse, &sum); \
return *sse; \
} \
\
unsigned int vp9_highbd_12_mse##W##x##H##_c(const uint8_t *src, \
int src_stride, \
const uint8_t *ref, \
int ref_stride, \
unsigned int *sse) { \
int sum; \
highbd_12_variance(src, src_stride, ref, ref_stride, W, H, sse, &sum); \
return *sse; \
}
HIGHBD_GET_VAR(8)
HIGHBD_GET_VAR(16)
HIGHBD_MSE(16, 16)
HIGHBD_MSE(16, 8)
HIGHBD_MSE(8, 16)
HIGHBD_MSE(8, 8)
HIGHBD_VAR(4, 4)
HIGHBD_SUBPIX_VAR(4, 4)
HIGHBD_SUBPIX_AVG_VAR(4, 4)
HIGHBD_VAR(4, 8)
HIGHBD_SUBPIX_VAR(4, 8)
HIGHBD_SUBPIX_AVG_VAR(4, 8)
HIGHBD_VAR(8, 4)
HIGHBD_SUBPIX_VAR(8, 4)
HIGHBD_SUBPIX_AVG_VAR(8, 4)
HIGHBD_VAR(8, 8)
HIGHBD_SUBPIX_VAR(8, 8)
HIGHBD_SUBPIX_AVG_VAR(8, 8)
HIGHBD_VAR(8, 16)
HIGHBD_SUBPIX_VAR(8, 16)
HIGHBD_SUBPIX_AVG_VAR(8, 16)
HIGHBD_VAR(16, 8)
HIGHBD_SUBPIX_VAR(16, 8)
HIGHBD_SUBPIX_AVG_VAR(16, 8)
HIGHBD_VAR(16, 16)
HIGHBD_SUBPIX_VAR(16, 16)
HIGHBD_SUBPIX_AVG_VAR(16, 16)
HIGHBD_VAR(16, 32)
HIGHBD_SUBPIX_VAR(16, 32)
HIGHBD_SUBPIX_AVG_VAR(16, 32)
HIGHBD_VAR(32, 16)
HIGHBD_SUBPIX_VAR(32, 16)
HIGHBD_SUBPIX_AVG_VAR(32, 16)
HIGHBD_VAR(32, 32)
HIGHBD_SUBPIX_VAR(32, 32)
HIGHBD_SUBPIX_AVG_VAR(32, 32)
HIGHBD_VAR(32, 64)
HIGHBD_SUBPIX_VAR(32, 64)
HIGHBD_SUBPIX_AVG_VAR(32, 64)
HIGHBD_VAR(64, 32)
HIGHBD_SUBPIX_VAR(64, 32)
HIGHBD_SUBPIX_AVG_VAR(64, 32)
HIGHBD_VAR(64, 64)
HIGHBD_SUBPIX_VAR(64, 64)
HIGHBD_SUBPIX_AVG_VAR(64, 64)
void vp9_highbd_comp_avg_pred(uint16_t *comp_pred, const uint8_t *pred8,
int width, int height, const uint8_t *ref8,
int ref_stride) {
int i, j;
uint16_t *pred = CONVERT_TO_SHORTPTR(pred8);
uint16_t *ref = CONVERT_TO_SHORTPTR(ref8);
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
const int tmp = pred[j] + ref[j];
comp_pred[j] = ROUND_POWER_OF_TWO(tmp, 1);
}
comp_pred += width;
pred += width;
ref += ref_stride;
}
}
#endif // CONFIG_VP9_HIGHBITDEPTH