/*
* Copyright 2011 The LibYuv 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 "libyuv/compare.h"
#include <float.h>
#include <math.h>
#ifdef _OPENMP
#include <omp.h>
#endif
#include "libyuv/basic_types.h"
#include "libyuv/compare_row.h"
#include "libyuv/cpu_id.h"
#include "libyuv/row.h"
#include "libyuv/video_common.h"
#ifdef __cplusplus
namespace libyuv {
extern "C" {
#endif
// hash seed of 5381 recommended.
LIBYUV_API
uint32 HashDjb2(const uint8* src, uint64 count, uint32 seed) {
const int kBlockSize = 1 << 15; // 32768;
int remainder;
uint32 (*HashDjb2_SSE)(const uint8* src, int count, uint32 seed) = HashDjb2_C;
#if defined(HAS_HASHDJB2_SSE41)
if (TestCpuFlag(kCpuHasSSE41)) {
HashDjb2_SSE = HashDjb2_SSE41;
}
#endif
#if defined(HAS_HASHDJB2_AVX2)
if (TestCpuFlag(kCpuHasAVX2)) {
HashDjb2_SSE = HashDjb2_AVX2;
}
#endif
while (count >= (uint64)(kBlockSize)) {
seed = HashDjb2_SSE(src, kBlockSize, seed);
src += kBlockSize;
count -= kBlockSize;
}
remainder = (int)count & ~15;
if (remainder) {
seed = HashDjb2_SSE(src, remainder, seed);
src += remainder;
count -= remainder;
}
remainder = (int)count & 15;
if (remainder) {
seed = HashDjb2_C(src, remainder, seed);
}
return seed;
}
static uint32 ARGBDetectRow_C(const uint8* argb, int width) {
int x;
for (x = 0; x < width - 1; x += 2) {
if (argb[0] != 255) { // First byte is not Alpha of 255, so not ARGB.
return FOURCC_BGRA;
}
if (argb[3] != 255) { // 4th byte is not Alpha of 255, so not BGRA.
return FOURCC_ARGB;
}
if (argb[4] != 255) { // Second pixel first byte is not Alpha of 255.
return FOURCC_BGRA;
}
if (argb[7] != 255) { // Second pixel 4th byte is not Alpha of 255.
return FOURCC_ARGB;
}
argb += 8;
}
if (width & 1) {
if (argb[0] != 255) { // First byte is not Alpha of 255, so not ARGB.
return FOURCC_BGRA;
}
if (argb[3] != 255) { // 4th byte is not Alpha of 255, so not BGRA.
return FOURCC_ARGB;
}
}
return 0;
}
// Scan an opaque argb image and return fourcc based on alpha offset.
// Returns FOURCC_ARGB, FOURCC_BGRA, or 0 if unknown.
LIBYUV_API
uint32 ARGBDetect(const uint8* argb, int stride_argb, int width, int height) {
uint32 fourcc = 0;
int h;
// Coalesce rows.
if (stride_argb == width * 4) {
width *= height;
height = 1;
stride_argb = 0;
}
for (h = 0; h < height && fourcc == 0; ++h) {
fourcc = ARGBDetectRow_C(argb, width);
argb += stride_argb;
}
return fourcc;
}
// TODO(fbarchard): Refactor into row function.
LIBYUV_API
uint64 ComputeSumSquareError(const uint8* src_a,
const uint8* src_b,
int count) {
// SumSquareError returns values 0 to 65535 for each squared difference.
// Up to 65536 of those can be summed and remain within a uint32.
// After each block of 65536 pixels, accumulate into a uint64.
const int kBlockSize = 65536;
int remainder = count & (kBlockSize - 1) & ~31;
uint64 sse = 0;
int i;
uint32 (*SumSquareError)(const uint8* src_a, const uint8* src_b, int count) =
SumSquareError_C;
#if defined(HAS_SUMSQUAREERROR_NEON)
if (TestCpuFlag(kCpuHasNEON)) {
SumSquareError = SumSquareError_NEON;
}
#endif
#if defined(HAS_SUMSQUAREERROR_SSE2)
if (TestCpuFlag(kCpuHasSSE2)) {
// Note only used for multiples of 16 so count is not checked.
SumSquareError = SumSquareError_SSE2;
}
#endif
#if defined(HAS_SUMSQUAREERROR_AVX2)
if (TestCpuFlag(kCpuHasAVX2)) {
// Note only used for multiples of 32 so count is not checked.
SumSquareError = SumSquareError_AVX2;
}
#endif
#ifdef _OPENMP
#pragma omp parallel for reduction(+ : sse)
#endif
for (i = 0; i < (count - (kBlockSize - 1)); i += kBlockSize) {
sse += SumSquareError(src_a + i, src_b + i, kBlockSize);
}
src_a += count & ~(kBlockSize - 1);
src_b += count & ~(kBlockSize - 1);
if (remainder) {
sse += SumSquareError(src_a, src_b, remainder);
src_a += remainder;
src_b += remainder;
}
remainder = count & 31;
if (remainder) {
sse += SumSquareError_C(src_a, src_b, remainder);
}
return sse;
}
LIBYUV_API
uint64 ComputeSumSquareErrorPlane(const uint8* src_a,
int stride_a,
const uint8* src_b,
int stride_b,
int width,
int height) {
uint64 sse = 0;
int h;
// Coalesce rows.
if (stride_a == width && stride_b == width) {
width *= height;
height = 1;
stride_a = stride_b = 0;
}
for (h = 0; h < height; ++h) {
sse += ComputeSumSquareError(src_a, src_b, width);
src_a += stride_a;
src_b += stride_b;
}
return sse;
}
LIBYUV_API
double SumSquareErrorToPsnr(uint64 sse, uint64 count) {
double psnr;
if (sse > 0) {
double mse = (double)count / (double)sse;
psnr = 10.0 * log10(255.0 * 255.0 * mse);
} else {
psnr = kMaxPsnr; // Limit to prevent divide by 0
}
if (psnr > kMaxPsnr)
psnr = kMaxPsnr;
return psnr;
}
LIBYUV_API
double CalcFramePsnr(const uint8* src_a,
int stride_a,
const uint8* src_b,
int stride_b,
int width,
int height) {
const uint64 samples = width * height;
const uint64 sse = ComputeSumSquareErrorPlane(src_a, stride_a, src_b,
stride_b, width, height);
return SumSquareErrorToPsnr(sse, samples);
}
LIBYUV_API
double I420Psnr(const uint8* src_y_a,
int stride_y_a,
const uint8* src_u_a,
int stride_u_a,
const uint8* src_v_a,
int stride_v_a,
const uint8* src_y_b,
int stride_y_b,
const uint8* src_u_b,
int stride_u_b,
const uint8* src_v_b,
int stride_v_b,
int width,
int height) {
const uint64 sse_y = ComputeSumSquareErrorPlane(src_y_a, stride_y_a, src_y_b,
stride_y_b, width, height);
const int width_uv = (width + 1) >> 1;
const int height_uv = (height + 1) >> 1;
const uint64 sse_u = ComputeSumSquareErrorPlane(
src_u_a, stride_u_a, src_u_b, stride_u_b, width_uv, height_uv);
const uint64 sse_v = ComputeSumSquareErrorPlane(
src_v_a, stride_v_a, src_v_b, stride_v_b, width_uv, height_uv);
const uint64 samples = width * height + 2 * (width_uv * height_uv);
const uint64 sse = sse_y + sse_u + sse_v;
return SumSquareErrorToPsnr(sse, samples);
}
static const int64 cc1 = 26634; // (64^2*(.01*255)^2
static const int64 cc2 = 239708; // (64^2*(.03*255)^2
static double Ssim8x8_C(const uint8* src_a,
int stride_a,
const uint8* src_b,
int stride_b) {
int64 sum_a = 0;
int64 sum_b = 0;
int64 sum_sq_a = 0;
int64 sum_sq_b = 0;
int64 sum_axb = 0;
int i;
for (i = 0; i < 8; ++i) {
int j;
for (j = 0; j < 8; ++j) {
sum_a += src_a[j];
sum_b += src_b[j];
sum_sq_a += src_a[j] * src_a[j];
sum_sq_b += src_b[j] * src_b[j];
sum_axb += src_a[j] * src_b[j];
}
src_a += stride_a;
src_b += stride_b;
}
{
const int64 count = 64;
// scale the constants by number of pixels
const int64 c1 = (cc1 * count * count) >> 12;
const int64 c2 = (cc2 * count * count) >> 12;
const int64 sum_a_x_sum_b = sum_a * sum_b;
const int64 ssim_n = (2 * sum_a_x_sum_b + c1) *
(2 * count * sum_axb - 2 * sum_a_x_sum_b + c2);
const int64 sum_a_sq = sum_a * sum_a;
const int64 sum_b_sq = sum_b * sum_b;
const int64 ssim_d =
(sum_a_sq + sum_b_sq + c1) *
(count * sum_sq_a - sum_a_sq + count * sum_sq_b - sum_b_sq + c2);
if (ssim_d == 0.0) {
return DBL_MAX;
}
return ssim_n * 1.0 / ssim_d;
}
}
// We are using a 8x8 moving window with starting location of each 8x8 window
// on the 4x4 pixel grid. Such arrangement allows the windows to overlap
// block boundaries to penalize blocking artifacts.
LIBYUV_API
double CalcFrameSsim(const uint8* src_a,
int stride_a,
const uint8* src_b,
int stride_b,
int width,
int height) {
int samples = 0;
double ssim_total = 0;
double (*Ssim8x8)(const uint8* src_a, int stride_a, const uint8* src_b,
int stride_b) = Ssim8x8_C;
// sample point start with each 4x4 location
int i;
for (i = 0; i < height - 8; i += 4) {
int j;
for (j = 0; j < width - 8; j += 4) {
ssim_total += Ssim8x8(src_a + j, stride_a, src_b + j, stride_b);
samples++;
}
src_a += stride_a * 4;
src_b += stride_b * 4;
}
ssim_total /= samples;
return ssim_total;
}
LIBYUV_API
double I420Ssim(const uint8* src_y_a,
int stride_y_a,
const uint8* src_u_a,
int stride_u_a,
const uint8* src_v_a,
int stride_v_a,
const uint8* src_y_b,
int stride_y_b,
const uint8* src_u_b,
int stride_u_b,
const uint8* src_v_b,
int stride_v_b,
int width,
int height) {
const double ssim_y =
CalcFrameSsim(src_y_a, stride_y_a, src_y_b, stride_y_b, width, height);
const int width_uv = (width + 1) >> 1;
const int height_uv = (height + 1) >> 1;
const double ssim_u = CalcFrameSsim(src_u_a, stride_u_a, src_u_b, stride_u_b,
width_uv, height_uv);
const double ssim_v = CalcFrameSsim(src_v_a, stride_v_a, src_v_b, stride_v_b,
width_uv, height_uv);
return ssim_y * 0.8 + 0.1 * (ssim_u + ssim_v);
}
#ifdef __cplusplus
} // extern "C"
} // namespace libyuv
#endif