libwebp/sharpyuv/sharpyuv_dsp.c
Maryla 29cc95ce4c Basic version of libsharpyuv in libwebp, in C.
It's self contained apart from a dependency on src/webp/types.h and src/dsp/cpu.h
For now it's only set up as an internal library, not an installable one.
Webp doesn't depend on it yet, the code is only duplicated.

Change-Id: I752799894f9d4105d0d296ddebd9f9641181a1ec
2022-02-18 14:52:44 +00:00

102 lines
3.1 KiB
C

// Copyright 2022 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING 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.
// -----------------------------------------------------------------------------
//
// Speed-critical functions for Sharp YUV.
//
// Author: Skal (pascal.massimino@gmail.com)
#include "sharpyuv/sharpyuv_dsp.h"
#include <assert.h>
#include <stdlib.h>
#include "src/dsp/cpu.h"
//-----------------------------------------------------------------------------
#if !WEBP_NEON_OMIT_C_CODE
#define MAX_Y ((1 << 10) - 1) // 10b precision over 16b-arithmetic
static uint16_t clip_y(int v) {
return (v < 0) ? 0 : (v > MAX_Y) ? MAX_Y : (uint16_t)v;
}
static uint64_t SharpYUVUpdateY_C(const uint16_t* ref, const uint16_t* src,
uint16_t* dst, int len) {
uint64_t diff = 0;
int i;
for (i = 0; i < len; ++i) {
const int diff_y = ref[i] - src[i];
const int new_y = (int)dst[i] + diff_y;
dst[i] = clip_y(new_y);
diff += (uint64_t)abs(diff_y);
}
return diff;
}
static void SharpYUVUpdateRGB_C(const int16_t* ref, const int16_t* src,
int16_t* dst, int len) {
int i;
for (i = 0; i < len; ++i) {
const int diff_uv = ref[i] - src[i];
dst[i] += diff_uv;
}
}
static void SharpYUVFilterRow_C(const int16_t* A, const int16_t* B, int len,
const uint16_t* best_y, uint16_t* out) {
int i;
for (i = 0; i < len; ++i, ++A, ++B) {
const int v0 = (A[0] * 9 + A[1] * 3 + B[0] * 3 + B[1] + 8) >> 4;
const int v1 = (A[1] * 9 + A[0] * 3 + B[1] * 3 + B[0] + 8) >> 4;
out[2 * i + 0] = clip_y(best_y[2 * i + 0] + v0);
out[2 * i + 1] = clip_y(best_y[2 * i + 1] + v1);
}
}
#endif // !WEBP_NEON_OMIT_C_CODE
#undef MAX_Y
//-----------------------------------------------------------------------------
uint64_t (*SharpYUVUpdateY)(const uint16_t* src, const uint16_t* ref,
uint16_t* dst, int len);
void (*SharpYUVUpdateRGB)(const int16_t* src, const int16_t* ref, int16_t* dst,
int len);
void (*SharpYUVFilterRow)(const int16_t* A, const int16_t* B, int len,
const uint16_t* best_y, uint16_t* out);
extern void InitSharpYUVSSE2(void);
extern void InitSharpYUVNEON(void);
WEBP_DSP_INIT_FUNC(InitSharpYuv) {
#if !WEBP_NEON_OMIT_C_CODE
SharpYUVUpdateY = SharpYUVUpdateY_C;
SharpYUVUpdateRGB = SharpYUVUpdateRGB_C;
SharpYUVFilterRow = SharpYUVFilterRow_C;
#endif
#if defined(WEBP_HAVE_SSE2)
if (VP8GetCPUInfo != NULL && VP8GetCPUInfo(kSSE2)) {
InitSharpYUVSSE2();
}
#endif // WEBP_HAVE_SSE2
#if defined(WEBP_HAVE_NEON)
if (WEBP_NEON_OMIT_C_CODE ||
(VP8GetCPUInfo != NULL && VP8GetCPUInfo(kNEON))) {
InitSharpYUVNEON();
}
#endif // WEBP_HAVE_NEON
assert(SharpYUVUpdateY != NULL);
assert(SharpYUVUpdateRGB != NULL);
assert(SharpYUVFilterRow != NULL);
}