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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant reason:default
#ifndef QCOLORTRCLUT_P_H
#define QCOLORTRCLUT_P_H
//
// W A R N I N G
// -------------
//
// This file is not part of the Qt API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
#include <QtGui/private/qtguiglobal_p.h>
#include <QtGui/qrgb.h>
#include <QtGui/qrgba64.h>
#include <QtCore/private/qsimd_p.h>
#include <cmath>
#include <memory>
#if defined(__SSE2__)
#include <emmintrin.h>
#elif defined(__ARM_NEON__)
#include <arm_neon.h>
#endif
QT_BEGIN_NAMESPACE
class QColorTransferGenericFunction;
class QColorTransferFunction;
class QColorTransferTable;
class QColorTrc;
class Q_GUI_EXPORT QColorTrcLut
{
public:
static constexpr uint32_t ShiftUp = 4; // Amount to shift up from 1->255
static constexpr uint32_t ShiftDown = (8 - ShiftUp); // Amount to shift down from 1->65280
static constexpr qsizetype Resolution = (1 << ShiftUp) * 255; // Number of entries in table
enum Direction {
ToLinear = 1,
FromLinear = 2,
BiLinear = ToLinear | FromLinear
};
static std::shared_ptr<QColorTrcLut> fromGamma(float gamma, Direction dir = BiLinear);
static std::shared_ptr<QColorTrcLut> fromTrc(const QColorTrc &trc, Direction dir = BiLinear);
void setFromGamma(float gamma, Direction dir = BiLinear);
void setFromTransferFunction(const QColorTransferFunction &transFn, Direction dir = BiLinear);
void setFromTransferTable(const QColorTransferTable &transTable, Direction dir = BiLinear);
void setFromTransferGenericFunction(const QColorTransferGenericFunction &transfn, Direction dir);
void setFromTrc(const QColorTrc &trc, Direction dir);
// The following methods all convert opaque or unpremultiplied colors:
QRgba64 toLinear64(QRgb rgb32) const
{
#if defined(__SSE2__)
__m128i v = _mm_cvtsi32_si128(rgb32);
v = _mm_unpacklo_epi8(v, _mm_setzero_si128());
const __m128i vidx = _mm_slli_epi16(v, ShiftUp);
const int ridx = _mm_extract_epi16(vidx, 2);
const int gidx = _mm_extract_epi16(vidx, 1);
const int bidx = _mm_extract_epi16(vidx, 0);
v = _mm_slli_epi16(v, 8); // a * 256
v = _mm_insert_epi16(v, m_toLinear[ridx], 0);
v = _mm_insert_epi16(v, m_toLinear[gidx], 1);
v = _mm_insert_epi16(v, m_toLinear[bidx], 2);
v = _mm_add_epi16(v, _mm_srli_epi16(v, 8));
QRgba64 rgba64;
_mm_storel_epi64(reinterpret_cast<__m128i *>(&rgba64), v);
return rgba64;
#elif defined(__ARM_NEON__) && Q_BYTE_ORDER == Q_LITTLE_ENDIAN
uint8x8_t v8 = vreinterpret_u8_u32(vmov_n_u32(rgb32));
uint16x4_t v16 = vget_low_u16(vmovl_u8(v8));
const uint16x4_t vidx = vshl_n_u16(v16, ShiftUp);
const int ridx = vget_lane_u16(vidx, 2);
const int gidx = vget_lane_u16(vidx, 1);
const int bidx = vget_lane_u16(vidx, 0);
v16 = vshl_n_u16(v16, 8); // a * 256
v16 = vset_lane_u16(m_toLinear[ridx], v16, 0);
v16 = vset_lane_u16(m_toLinear[gidx], v16, 1);
v16 = vset_lane_u16(m_toLinear[bidx], v16, 2);
v16 = vadd_u16(v16, vshr_n_u16(v16, 8));
return QRgba64::fromRgba64(vget_lane_u64(vreinterpret_u64_u16(v16), 0));
#else
uint r = m_toLinear[qRed(rgb32) << ShiftUp];
uint g = m_toLinear[qGreen(rgb32) << ShiftUp];
uint b = m_toLinear[qBlue(rgb32) << ShiftUp];
r = r + (r >> 8);
g = g + (g >> 8);
b = b + (b >> 8);
return QRgba64::fromRgba64(r, g, b, qAlpha(rgb32) * 257);
#endif
}
QRgba64 toLinear64(QRgba64) const = delete;
QRgb toLinear(QRgb rgb32) const
{
return convertWithTable(rgb32, m_toLinear.get());
}
QRgba64 toLinear(QRgba64 rgb64) const
{
return convertWithTable(rgb64, m_toLinear.get());
}
float u8ToLinearF32(int c) const
{
ushort v = m_toLinear[c << ShiftUp];
return v * (1.0f / (255*256));
}
float u16ToLinearF32(int c) const
{
c -= (c >> 8);
ushort v = m_toLinear[c >> ShiftDown];
return v * (1.0f / (255*256));
}
float toLinear(float f) const
{
ushort v = m_toLinear[(int)(f * Resolution + 0.5f)];
return v * (1.0f / (255*256));
}
QRgb fromLinear64(QRgba64 rgb64) const
{
#if defined(__SSE2__)
__m128i v = _mm_loadl_epi64(reinterpret_cast<const __m128i *>(&rgb64));
v = _mm_sub_epi16(v, _mm_srli_epi16(v, 8));
const __m128i vidx = _mm_srli_epi16(v, ShiftDown);
const int ridx = _mm_extract_epi16(vidx, 0);
const int gidx = _mm_extract_epi16(vidx, 1);
const int bidx = _mm_extract_epi16(vidx, 2);
v = _mm_insert_epi16(v, m_fromLinear[ridx], 2);
v = _mm_insert_epi16(v, m_fromLinear[gidx], 1);
v = _mm_insert_epi16(v, m_fromLinear[bidx], 0);
v = _mm_add_epi16(v, _mm_set1_epi16(0x80));
v = _mm_srli_epi16(v, 8);
v = _mm_packus_epi16(v, v);
return _mm_cvtsi128_si32(v);
#elif defined(__ARM_NEON__) && Q_BYTE_ORDER == Q_LITTLE_ENDIAN
uint16x4_t v = vreinterpret_u16_u64(vmov_n_u64(rgb64));
v = vsub_u16(v, vshr_n_u16(v, 8));
const uint16x4_t vidx = vshr_n_u16(v, ShiftDown);
const int ridx = vget_lane_u16(vidx, 0);
const int gidx = vget_lane_u16(vidx, 1);
const int bidx = vget_lane_u16(vidx, 2);
v = vset_lane_u16(m_fromLinear[ridx], v, 2);
v = vset_lane_u16(m_fromLinear[gidx], v, 1);
v = vset_lane_u16(m_fromLinear[bidx], v, 0);
uint8x8_t v8 = vrshrn_n_u16(vcombine_u16(v, v), 8);
return vget_lane_u32(vreinterpret_u32_u8(v8), 0);
#else
uint a = rgb64.alpha();
uint r = rgb64.red();
uint g = rgb64.green();
uint b = rgb64.blue();
a = a - (a >> 8);
r = r - (r >> 8);
g = g - (g >> 8);
b = b - (b >> 8);
a = (a + 0x80) >> 8;
r = (m_fromLinear[r >> ShiftDown] + 0x80) >> 8;
g = (m_fromLinear[g >> ShiftDown] + 0x80) >> 8;
b = (m_fromLinear[b >> ShiftDown] + 0x80) >> 8;
return (a << 24) | (r << 16) | (g << 8) | b;
#endif
}
QRgb fromLinear(QRgb rgb32) const
{
return convertWithTable(rgb32, m_fromLinear.get());
}
QRgba64 fromLinear(QRgba64 rgb64) const
{
return convertWithTable(rgb64, m_fromLinear.get());
}
int u8FromLinearF32(float f) const
{
ushort v = m_fromLinear[(int)(f * Resolution + 0.5f)];
return (v + 0x80) >> 8;
}
int u16FromLinearF32(float f) const
{
ushort v = m_fromLinear[(int)(f * Resolution + 0.5f)];
return v + (v >> 8);
}
float fromLinear(float f) const
{
ushort v = m_fromLinear[(int)(f * Resolution + 0.5f)];
return v * (1.0f / (255*256));
}
// We translate to 0-65280 (255*256) instead to 0-65535 to make simple
// shifting an accurate conversion.
// We translate from 0->Resolution (4080 = 255*16) for the same speed up,
// and to keep the tables small enough to fit in most inner caches.
std::unique_ptr<ushort[]> m_toLinear; // [0->Resolution] -> [0-65280]
std::unique_ptr<ushort[]> m_fromLinear; // [0->Resolution] -> [0-65280]
ushort m_unclampedToLinear = Resolution;
private:
QColorTrcLut() = default;
static std::shared_ptr<QColorTrcLut> create();
Q_ALWAYS_INLINE static QRgb convertWithTable(QRgb rgb32, const ushort *table)
{
const int r = (table[qRed(rgb32) << ShiftUp] + 0x80) >> 8;
const int g = (table[qGreen(rgb32) << ShiftUp] + 0x80) >> 8;
const int b = (table[qBlue(rgb32) << ShiftUp] + 0x80) >> 8;
return (rgb32 & 0xff000000) | (r << 16) | (g << 8) | b;
}
Q_ALWAYS_INLINE static QRgba64 convertWithTable(QRgba64 rgb64, const ushort *table)
{
#if defined(__SSE2__)
__m128i v = _mm_loadl_epi64(reinterpret_cast<const __m128i *>(&rgb64));
v = _mm_sub_epi16(v, _mm_srli_epi16(v, 8));
const __m128i vidx = _mm_srli_epi16(v, ShiftDown);
const int ridx = _mm_extract_epi16(vidx, 2);
const int gidx = _mm_extract_epi16(vidx, 1);
const int bidx = _mm_extract_epi16(vidx, 0);
v = _mm_insert_epi16(v, table[ridx], 2);
v = _mm_insert_epi16(v, table[gidx], 1);
v = _mm_insert_epi16(v, table[bidx], 0);
v = _mm_add_epi16(v, _mm_srli_epi16(v, 8));
QRgba64 rgba64;
_mm_storel_epi64(reinterpret_cast<__m128i *>(&rgba64), v);
return rgba64;
#elif defined(__ARM_NEON__) && Q_BYTE_ORDER == Q_LITTLE_ENDIAN
uint16x4_t v = vreinterpret_u16_u64(vmov_n_u64(rgb64));
v = vsub_u16(v, vshr_n_u16(v, 8));
const uint16x4_t vidx = vshr_n_u16(v, ShiftDown);
const int ridx = vget_lane_u16(vidx, 2);
const int gidx = vget_lane_u16(vidx, 1);
const int bidx = vget_lane_u16(vidx, 0);
v = vset_lane_u16(table[ridx], v, 2);
v = vset_lane_u16(table[gidx], v, 1);
v = vset_lane_u16(table[bidx], v, 0);
v = vadd_u16(v, vshr_n_u16(v, 8));
return QRgba64::fromRgba64(vget_lane_u64(vreinterpret_u64_u16(v), 0));
#else
ushort r = rgb64.red();
ushort g = rgb64.green();
ushort b = rgb64.blue();
r = r - (r >> 8);
g = g - (g >> 8);
b = b - (b >> 8);
r = table[r >> ShiftDown];
g = table[g >> ShiftDown];
b = table[b >> ShiftDown];
r = r + (r >> 8);
g = g + (g >> 8);
b = b + (b >> 8);
return QRgba64::fromRgba64(r, g, b, rgb64.alpha());
#endif
}
};
QT_END_NAMESPACE
#endif // QCOLORTRCLUT_P_H