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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
#include "qmath.h"
#include "qdrawhelper_p.h"
#include "qmemrotate_p.h"
#include "qpainter.h"
#include <memory>
QT_BEGIN_NAMESPACE
namespace {
template <int shift>
inline int qt_static_shift(int value)
{
if (shift == 0)
return value;
else if (shift > 0)
return value << (uint(shift) & 0x1f);
else
return value >> (uint(-shift) & 0x1f);
}
template<int aprec, int zprec>
inline void qt_blurinner(uchar *bptr, int &zR, int &zG, int &zB, int &zA, int alpha)
{
QRgb *pixel = (QRgb *)bptr;
#define Z_MASK (0xff << zprec)
const int A_zprec = qt_static_shift<zprec - 24>(*pixel) & Z_MASK;
const int R_zprec = qt_static_shift<zprec - 16>(*pixel) & Z_MASK;
const int G_zprec = qt_static_shift<zprec - 8>(*pixel) & Z_MASK;
const int B_zprec = qt_static_shift<zprec>(*pixel) & Z_MASK;
#undef Z_MASK
const int zR_zprec = zR >> aprec;
const int zG_zprec = zG >> aprec;
const int zB_zprec = zB >> aprec;
const int zA_zprec = zA >> aprec;
zR += alpha * (R_zprec - zR_zprec);
zG += alpha * (G_zprec - zG_zprec);
zB += alpha * (B_zprec - zB_zprec);
zA += alpha * (A_zprec - zA_zprec);
#define ZA_MASK (0xff << (zprec + aprec))
*pixel =
qt_static_shift<24 - zprec - aprec>(zA & ZA_MASK)
| qt_static_shift<16 - zprec - aprec>(zR & ZA_MASK)
| qt_static_shift<8 - zprec - aprec>(zG & ZA_MASK)
| qt_static_shift<-zprec - aprec>(zB & ZA_MASK);
#undef ZA_MASK
}
const int alphaIndex = (QSysInfo::ByteOrder == QSysInfo::BigEndian ? 0 : 3);
template<int aprec, int zprec>
inline void qt_blurinner_alphaOnly(uchar *bptr, int &z, int alpha)
{
const int A_zprec = int(*(bptr)) << zprec;
const int z_zprec = z >> aprec;
z += alpha * (A_zprec - z_zprec);
*(bptr) = z >> (zprec + aprec);
}
template<int aprec, int zprec, bool alphaOnly>
inline void qt_blurrow(QImage & im, int line, int alpha)
{
uchar *bptr = im.scanLine(line);
int zR = 0, zG = 0, zB = 0, zA = 0;
if (alphaOnly && im.format() != QImage::Format_Indexed8)
bptr += alphaIndex;
const int stride = im.depth() >> 3;
const int im_width = im.width();
for (int index = 0; index < im_width; ++index) {
if (alphaOnly)
qt_blurinner_alphaOnly<aprec, zprec>(bptr, zA, alpha);
else
qt_blurinner<aprec, zprec>(bptr, zR, zG, zB, zA, alpha);
bptr += stride;
}
bptr -= stride;
for (int index = im_width - 2; index >= 0; --index) {
bptr -= stride;
if (alphaOnly)
qt_blurinner_alphaOnly<aprec, zprec>(bptr, zA, alpha);
else
qt_blurinner<aprec, zprec>(bptr, zR, zG, zB, zA, alpha);
}
}
/*
* expblur(QImage &img, int radius)
*
* Based on exponential blur algorithm by Jani Huhtanen
*
* In-place blur of image 'img' with kernel
* of approximate radius 'radius'.
*
* Blurs with two sided exponential impulse
* response.
*
* aprec = precision of alpha parameter
* in fixed-point format 0.aprec
*
* zprec = precision of state parameters
* zR,zG,zB and zA in fp format 8.zprec
*/
template <int aprec, int zprec, bool alphaOnly>
void expblur(QImage &img, qreal radius, bool improvedQuality = false, int transposed = 0)
{
// halve the radius if we're using two passes
if (improvedQuality)
radius *= qreal(0.5);
Q_ASSERT(img.format() == QImage::Format_ARGB32_Premultiplied
|| img.format() == QImage::Format_RGB32
|| img.format() == QImage::Format_Indexed8
|| img.format() == QImage::Format_Grayscale8);
// choose the alpha such that pixels at radius distance from a fully
// saturated pixel will have an alpha component of no greater than
// the cutOffIntensity
const qreal cutOffIntensity = 2;
int alpha = radius <= qreal(1e-5)
? ((1 << aprec)-1)
: qRound((1<<aprec)*(1 - qPow(cutOffIntensity * (1 / qreal(255)), 1 / radius)));
int img_height = img.height();
for (int row = 0; row < img_height; ++row) {
for (int i = 0; i <= int(improvedQuality); ++i)
qt_blurrow<aprec, zprec, alphaOnly>(img, row, alpha);
}
QImage temp(img.height(), img.width(), img.format());
temp.setDevicePixelRatio(img.devicePixelRatio());
if (transposed >= 0) {
if (img.depth() == 8) {
qt_memrotate270(reinterpret_cast<const quint8*>(img.bits()),
img.width(), img.height(), img.bytesPerLine(),
reinterpret_cast<quint8*>(temp.bits()),
temp.bytesPerLine());
} else {
qt_memrotate270(reinterpret_cast<const quint32*>(img.bits()),
img.width(), img.height(), img.bytesPerLine(),
reinterpret_cast<quint32*>(temp.bits()),
temp.bytesPerLine());
}
} else {
if (img.depth() == 8) {
qt_memrotate90(reinterpret_cast<const quint8*>(img.bits()),
img.width(), img.height(), img.bytesPerLine(),
reinterpret_cast<quint8*>(temp.bits()),
temp.bytesPerLine());
} else {
qt_memrotate90(reinterpret_cast<const quint32*>(img.bits()),
img.width(), img.height(), img.bytesPerLine(),
reinterpret_cast<quint32*>(temp.bits()),
temp.bytesPerLine());
}
}
img_height = temp.height();
for (int row = 0; row < img_height; ++row) {
for (int i = 0; i <= int(improvedQuality); ++i)
qt_blurrow<aprec, zprec, alphaOnly>(temp, row, alpha);
}
if (transposed == 0) {
if (img.depth() == 8) {
qt_memrotate90(reinterpret_cast<const quint8*>(temp.bits()),
temp.width(), temp.height(), temp.bytesPerLine(),
reinterpret_cast<quint8*>(img.bits()),
img.bytesPerLine());
} else {
qt_memrotate90(reinterpret_cast<const quint32*>(temp.bits()),
temp.width(), temp.height(), temp.bytesPerLine(),
reinterpret_cast<quint32*>(img.bits()),
img.bytesPerLine());
}
} else {
img = temp;
}
}
} // namespace
#define AVG(a,b) ( ((((a)^(b)) & 0xfefefefeUL) >> 1) + ((a)&(b)) )
#define AVG16(a,b) ( ((((a)^(b)) & 0xf7deUL) >> 1) + ((a)&(b)) )
QImage qt_halfScaled(const QImage &source)
{
if (source.width() < 2 || source.height() < 2)
return QImage();
QImage srcImage = source;
if (source.format() == QImage::Format_Indexed8 || source.format() == QImage::Format_Grayscale8) {
// assumes grayscale
QImage dest(source.width() / 2, source.height() / 2, srcImage.format());
dest.setDevicePixelRatio(source.devicePixelRatio());
const uchar *src = reinterpret_cast<const uchar*>(const_cast<const QImage &>(srcImage).bits());
qsizetype sx = srcImage.bytesPerLine();
qsizetype sx2 = sx << 1;
uchar *dst = reinterpret_cast<uchar*>(dest.bits());
qsizetype dx = dest.bytesPerLine();
int ww = dest.width();
int hh = dest.height();
for (int y = hh; y; --y, dst += dx, src += sx2) {
const uchar *p1 = src;
const uchar *p2 = src + sx;
uchar *q = dst;
for (int x = ww; x; --x, ++q, p1 += 2, p2 += 2)
*q = ((int(p1[0]) + int(p1[1]) + int(p2[0]) + int(p2[1])) + 2) >> 2;
}
return dest;
} else if (source.format() == QImage::Format_ARGB8565_Premultiplied) {
QImage dest(source.width() / 2, source.height() / 2, srcImage.format());
dest.setDevicePixelRatio(source.devicePixelRatio());
const uchar *src = reinterpret_cast<const uchar*>(const_cast<const QImage &>(srcImage).bits());
qsizetype sx = srcImage.bytesPerLine();
qsizetype sx2 = sx << 1;
uchar *dst = reinterpret_cast<uchar*>(dest.bits());
qsizetype dx = dest.bytesPerLine();
int ww = dest.width();
int hh = dest.height();
for (int y = hh; y; --y, dst += dx, src += sx2) {
const uchar *p1 = src;
const uchar *p2 = src + sx;
uchar *q = dst;
for (int x = ww; x; --x, q += 3, p1 += 6, p2 += 6) {
// alpha
q[0] = AVG(AVG(p1[0], p1[3]), AVG(p2[0], p2[3]));
// rgb
const quint16 p16_1 = (p1[2] << 8) | p1[1];
const quint16 p16_2 = (p1[5] << 8) | p1[4];
const quint16 p16_3 = (p2[2] << 8) | p2[1];
const quint16 p16_4 = (p2[5] << 8) | p2[4];
const quint16 result = AVG16(AVG16(p16_1, p16_2), AVG16(p16_3, p16_4));
q[1] = result & 0xff;
q[2] = result >> 8;
}
}
return dest;
} else if (source.format() != QImage::Format_ARGB32_Premultiplied
&& source.format() != QImage::Format_RGB32)
{
srcImage = source.convertToFormat(QImage::Format_ARGB32_Premultiplied);
}
QImage dest(source.width() / 2, source.height() / 2, srcImage.format());
dest.setDevicePixelRatio(source.devicePixelRatio());
const quint32 *src = reinterpret_cast<const quint32*>(const_cast<const QImage &>(srcImage).bits());
qsizetype sx = srcImage.bytesPerLine() >> 2;
qsizetype sx2 = sx << 1;
quint32 *dst = reinterpret_cast<quint32*>(dest.bits());
qsizetype dx = dest.bytesPerLine() >> 2;
int ww = dest.width();
int hh = dest.height();
for (int y = hh; y; --y, dst += dx, src += sx2) {
const quint32 *p1 = src;
const quint32 *p2 = src + sx;
quint32 *q = dst;
for (int x = ww; x; --x, q++, p1 += 2, p2 += 2)
*q = AVG(AVG(p1[0], p1[1]), AVG(p2[0], p2[1]));
}
return dest;
}
#undef AVG
#undef AVG16
Q_GUI_EXPORT void qt_blurImage(QPainter *p, QImage &blurImage, qreal radius, bool quality, bool alphaOnly, int transposed = 0)
{
if (blurImage.format() != QImage::Format_ARGB32_Premultiplied
&& blurImage.format() != QImage::Format_RGB32)
{
blurImage = std::move(blurImage).convertToFormat(QImage::Format_ARGB32_Premultiplied);
}
qreal scale = 1;
if (radius >= 4 && blurImage.width() >= 2 && blurImage.height() >= 2) {
blurImage = qt_halfScaled(blurImage);
scale = 2;
radius *= qreal(0.5);
}
if (alphaOnly)
expblur<12, 10, true>(blurImage, radius, quality, transposed);
else
expblur<12, 10, false>(blurImage, radius, quality, transposed);
if (p) {
p->scale(scale, scale);
p->setRenderHint(QPainter::SmoothPixmapTransform);
p->drawImage(QRect(QPoint(0, 0), blurImage.deviceIndependentSize().toSize()), blurImage);
}
}
Q_GUI_EXPORT void qt_blurImage(QImage &blurImage, qreal radius, bool quality, int transposed = 0)
{
if (blurImage.format() == QImage::Format_Indexed8 || blurImage.format() == QImage::Format_Grayscale8)
expblur<12, 10, true>(blurImage, radius, quality, transposed);
else
expblur<12, 10, false>(blurImage, radius, quality, transposed);
}
QT_END_NAMESPACE