qpixmapfilter.cpp File Reference

#include <qglobal.h>
#include <QDebug>
#include "qpainter.h"
#include "qpixmap.h"
#include "qpixmapfilter_p.h"
#include "qvarlengtharray.h"
#include "private/qapplication_p.h"
#include "private/qgraphicssystem_p.h"
#include "private/qpaintengineex_p.h"
#include "private/qpaintengine_raster_p.h"
#include "qmath.h"
#include "private/qmath_p.h"
#include "private/qmemrotate_p.h"
#include "private/qdrawhelper_p.h"

Go to the source code of this file.

Classes
class	QPixmapBlurFilterPrivate
class	QPixmapColorizeFilterPrivate
class	QPixmapConvolutionFilterPrivate
class	QPixmapDropShadowFilterPrivate
class	QPixmapFilterPrivate

Macros
#define	AVG(a, b)   ( ((((a)^(b)) & 0xfefefefeUL) >> 1) + ((a)&(b)) )
#define	AVG16(a, b)   ( ((((a)^(b)) & 0xf7deUL) >> 1) + ((a)&(b)) )
#define	Z_MASK   (0xff << zprec)
#define	ZA_MASK   (0xff << (zprec + aprec))

Functions
static void	convolute (QImage *destImage, const QPointF &pos, const QImage &srcImage, const QRectF &srcRect, QPainter::CompositionMode mode, qreal *kernel, int kernelWidth, int kernelHeight)
template<int aprec, int zprec, bool alphaOnly>
void	expblur (QImage &img, qreal radius, bool improvedQuality=false, int transposed=0)
static void	grayscale (const QImage &image, QImage &dest, const QRect &rect=QRect())
Q_GUI_EXPORT void	qt_blurImage (QPainter *p, QImage &blurImage, qreal radius, bool quality, bool alphaOnly, int transposed=0)
Q_GUI_EXPORT void	qt_blurImage (QImage &blurImage, qreal radius, bool quality, int transposed=0)
template<int aprec, int zprec>
void	qt_blurinner (uchar *bptr, int &zR, int &zG, int &zB, int &zA, int alpha)
template<int aprec, int zprec>
void	qt_blurinner_alphaOnly (uchar *bptr, int &z, int alpha)
template<int aprec, int zprec, bool alphaOnly>
void	qt_blurrow (QImage &im, int line, int alpha)
Q_GUI_EXPORT QImage	qt_halfScaled (const QImage &source)
Q_GUI_EXPORT bool	qt_scaleForTransform (const QTransform &transform, qreal *scale)
template<int shift>
int	qt_static_shift (int value)

Variables
const int	alphaIndex = (QSysInfo::ByteOrder == QSysInfo::BigEndian ? 0 : 3)
const qreal	radiusScale = qreal(2.5)

Macro Definition Documentation

AVG

#define AVG	(		a,
			b
	)		( ((((a)^(b)) & 0xfefefefeUL) >> 1) + ((a)&(b)) )

Definition at line 794 of file qpixmapfilter.cpp.

Referenced by qt_halfScaled().

AVG16

#define AVG16	(		a,
			b
	)		( ((((a)^(b)) & 0xf7deUL) >> 1) + ((a)&(b)) )

Definition at line 795 of file qpixmapfilter.cpp.

Referenced by qt_halfScaled().

Z_MASK

#define Z_MASK   (0xff << zprec)

Referenced by qt_blurinner().

ZA_MASK

#define ZA_MASK   (0xff << (zprec + aprec))

Referenced by qt_blurinner().

Function Documentation

convolute()

static void convolute ( QImage *  destImage, const QPointF &  pos, const QImage &  srcImage, const QRectF &  srcRect, QPainter::CompositionMode  mode, qreal *  kernel, int  kernelWidth, int  kernelHeight  )

static

Definition at line 322 of file qpixmapfilter.cpp.

Referenced by QPixmapConvolutionFilter::draw().

{
    const QImage processImage = (srcImage.format() != QImage::Format_ARGB32_Premultiplied ) ?               srcImage.convertToFormat(QImage::Format_ARGB32_Premultiplied) : srcImage;
    // TODO: support also other formats directly without copying

    int *fixedKernel = new int[kernelWidth*kernelHeight];
    for(int i = 0; i < kernelWidth*kernelHeight; i++)
    {
        fixedKernel[i] = (int)(65536 * kernel[i]);
    }
    QRectF trect = srcRect.isNull() ? processImage.rect() : srcRect;
    trect.moveTo(pos);
    QRectF bounded = trect.adjusted(-kernelWidth / 2, -kernelHeight / 2, (kernelWidth - 1) / 2, (kernelHeight - 1) / 2);
    QRect rect = bounded.toAlignedRect();
    QRect targetRect = rect.intersected(destImage->rect());

    QRectF srect = srcRect.isNull() ? processImage.rect() : srcRect;
    QRectF sbounded = srect.adjusted(-kernelWidth / 2, -kernelHeight / 2, (kernelWidth - 1) / 2, (kernelHeight - 1) / 2);
    QPoint srcStartPoint = sbounded.toAlignedRect().topLeft()+(targetRect.topLeft()-rect.topLeft());

    const uint *sourceStart = (uint*)processImage.scanLine(0);
    uint *outputStart = (uint*)destImage->scanLine(0);

    int yk = srcStartPoint.y();
    for (int y = targetRect.top(); y <= targetRect.bottom(); y++) {
        uint* output = outputStart + (destImage->bytesPerLine()/sizeof(uint))*y+targetRect.left();
        int xk = srcStartPoint.x();
        for(int x = targetRect.left(); x <= targetRect.right(); x++) {
            int r = 0;
            int g = 0;
            int b = 0;
            int a = 0;

            // some out of bounds pre-checking to avoid inner-loop ifs
            int kernely = -kernelHeight/2;
            int starty = 0;
            int endy = kernelHeight;
            if(yk+kernely+endy >= srcImage.height())
                endy = kernelHeight-((yk+kernely+endy)-srcImage.height())-1;
            if(yk+kernely < 0)
                starty = -(yk+kernely);

            int kernelx = -kernelWidth/2;
            int startx = 0;
            int endx = kernelWidth;
            if(xk+kernelx+endx >= srcImage.width())
                endx = kernelWidth-((xk+kernelx+endx)-srcImage.width())-1;
            if(xk+kernelx < 0)
                startx = -(xk+kernelx);

            for (int ys = starty; ys < endy; ys ++) {
                const uint *pix = sourceStart + (processImage.bytesPerLine()/sizeof(uint))*(yk+kernely+ys) + ((xk+kernelx+startx));
                const uint *endPix = pix+endx-startx;
                int kernelPos = ys*kernelWidth+startx;
                while (pix < endPix) {
                    int factor = fixedKernel[kernelPos++];
                    a += (((*pix) & 0xff000000)>>24) * factor;
                    r += (((*pix) & 0x00ff0000)>>16) * factor;
                    g += (((*pix) & 0x0000ff00)>>8 ) * factor;
                    b += (((*pix) & 0x000000ff)    ) * factor;
                    pix++;
                }
            }

            r = qBound((int)0, r >> 16, (int)255);
            g = qBound((int)0, g >> 16, (int)255);
            b = qBound((int)0, b >> 16, (int)255);
            a = qBound((int)0, a >> 16, (int)255);
            // composition mode checking could be moved outside of loop
            if(mode == QPainter::CompositionMode_Source) {
                uint color = (a<<24)+(r<<16)+(g<<8)+b;
                *output++ = color;
            } else {
                uint current = *output;
                uchar ca = (current&0xff000000)>>24;
                uchar cr = (current&0x00ff0000)>>16;
                uchar cg = (current&0x0000ff00)>>8;
                uchar cb = (current&0x000000ff);
                uint color =
                        (((ca*(255-a) >> 8)+a) << 24)+
                        (((cr*(255-a) >> 8)+r) << 16)+
                        (((cg*(255-a) >> 8)+g) << 8)+
                        (((cb*(255-a) >> 8)+b));
                *output++ = color;;
            }
            xk++;
        }
        yk++;
    }
    delete[] fixedKernel;
}

expblur()

template<int aprec, int zprec, bool alphaOnly>

void expblur	(	QImage &	img,
		qreal	radius,
		bool	improvedQuality = false,
		int	transposed = 0
	)

Definition at line 721 of file qpixmapfilter.cpp.

{
    // 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);

    // 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());
    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;
    }
}

grayscale()

static void grayscale ( const QImage &  image, QImage &  dest, const QRect &  rect = QRect()  )

static

Definition at line 977 of file qpixmapfilter.cpp.

Referenced by QPixmapColorizeFilter::draw(), and QTiffHandler::read().

{
    QRect destRect = rect;
    QRect srcRect = rect;
    if (rect.isNull()) {
        srcRect = dest.rect();
        destRect = dest.rect();
    }
    if (&image != &dest) {
        destRect.moveTo(QPoint(0, 0));
    }

    unsigned int *data = (unsigned int *)image.bits();
    unsigned int *outData = (unsigned int *)dest.bits();

    if (dest.size() == image.size() && image.rect() == srcRect) {
        // a bit faster loop for grayscaling everything
        int pixels = dest.width() * dest.height();
        for (int i = 0; i < pixels; ++i) {
            int val = qGray(data[i]);
            outData[i] = qRgba(val, val, val, qAlpha(data[i]));
        }
    } else {
        int yd = destRect.top();
        for (int y = srcRect.top(); y <= srcRect.bottom() && y < image.height(); y++) {
            data = (unsigned int*)image.scanLine(y);
            outData = (unsigned int*)dest.scanLine(yd++);
            int xd = destRect.left();
            for (int x = srcRect.left(); x <= srcRect.right() && x < image.width(); x++) {
                int val = qGray(data[x]);
                outData[xd++] = qRgba(val, val, val, qAlpha(data[x]));
            }
        }
    }
}

qt_blurImage() [1/2]

Q_GUI_EXPORT void qt_blurImage	(	QPainter *	p,
		QImage &	blurImage,
		qreal	radius,
		bool	quality,
		bool	alphaOnly,
		int	transposed = 0
	)

Definition at line 885 of file qpixmapfilter.cpp.

Referenced by QPixmapBlurFilter::draw(), and QPixmapDropShadowFilter::draw().

{
    if (blurImage.format() != QImage::Format_ARGB32_Premultiplied
        && blurImage.format() != QImage::Format_RGB32)
    {
        blurImage = 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(0, 0, blurImage.width(), blurImage.height()), blurImage);
    }
}

qt_blurImage() [2/2]

Q_GUI_EXPORT void qt_blurImage	(	QImage &	blurImage,
		qreal	radius,
		bool	quality,
		int	transposed = 0
	)

Definition at line 912 of file qpixmapfilter.cpp.

Referenced by QGLPixmapBlurFilter::processGL(), and QGLPixmapDropShadowFilter::processGL().

{
    if (blurImage.format() == QImage::Format_Indexed8)
        expblur<12, 10, true>(blurImage, radius, quality, transposed);
    else
        expblur<12, 10, false>(blurImage, radius, quality, transposed);
}

qt_blurinner()

template<int aprec, int zprec>

void qt_blurinner ( uchar *  bptr, int &  zR, int &  zG, int &  zB, int &  zA, int  alpha  )

inline

Definition at line 631 of file qpixmapfilter.cpp.

{
    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
}

qt_blurinner_alphaOnly()

template<int aprec, int zprec>

void qt_blurinner_alphaOnly ( uchar *  bptr, int &  z, int  alpha  )

inline

Definition at line 664 of file qpixmapfilter.cpp.

{
    const int A_zprec = int(*(bptr)) << zprec;
    const int z_zprec = z >> aprec;
    z += alpha * (A_zprec - z_zprec);
    *(bptr) = z >> (zprec + aprec);
}

qt_blurrow()

template<int aprec, int zprec, bool alphaOnly>

void qt_blurrow ( QImage &  im, int  line, int  alpha  )

inline

Definition at line 673 of file qpixmapfilter.cpp.

{
    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);
    }
}

qt_halfScaled()

Q_GUI_EXPORT QImage qt_halfScaled

(

const QImage &

source

)

Definition at line 797 of file qpixmapfilter.cpp.

Referenced by QGLBlurTextureInfo::paddedImage(), QGLPixmapBlurFilter::processGL(), QGLPixmapDropShadowFilter::processGL(), and qt_blurImage().

{
    if (source.width() < 2 || source.height() < 2)
        return QImage();

    QImage srcImage = source;

    if (source.format() == QImage::Format_Indexed8) {
        // assumes grayscale
        QImage dest(source.width() / 2, source.height() / 2, srcImage.format());

        const uchar *src = reinterpret_cast<const uchar*>(const_cast<const QImage &>(srcImage).bits());
        int sx = srcImage.bytesPerLine();
        int sx2 = sx << 1;

        uchar *dst = reinterpret_cast<uchar*>(dest.bits());
        int 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());

        const uchar *src = reinterpret_cast<const uchar*>(const_cast<const QImage &>(srcImage).bits());
        int sx = srcImage.bytesPerLine();
        int sx2 = sx << 1;

        uchar *dst = reinterpret_cast<uchar*>(dest.bits());
        int 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());

    const quint32 *src = reinterpret_cast<const quint32*>(const_cast<const QImage &>(srcImage).bits());
    int sx = srcImage.bytesPerLine() >> 2;
    int sx2 = sx << 1;

    quint32 *dst = reinterpret_cast<quint32*>(dest.bits());
    int 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;
}

qt_scaleForTransform()

Q_GUI_EXPORT bool qt_scaleForTransform	(	const QTransform &	transform,
		qreal *	scale
	)

Definition at line 2407 of file qtransform.cpp.

Referenced by QPixmapBlurFilter::draw(), qt_blurImage(), and QX11PaintEngine::updateMatrix().

{
    const QTransform::TransformationType type = transform.type();
    if (type <= QTransform::TxTranslate) {
        if (scale)
            *scale = 1;
        return true;
    } else if (type == QTransform::TxScale) {
        const qreal xScale = qAbs(transform.m11());
        const qreal yScale = qAbs(transform.m22());
        if (scale)
            *scale = qMax(xScale, yScale);
        return qFuzzyCompare(xScale, yScale);
    }

    const qreal xScale = transform.m11() * transform.m11()
                         + transform.m21() * transform.m21();
    const qreal yScale = transform.m12() * transform.m12()
                         + transform.m22() * transform.m22();
    if (scale)
        *scale = qSqrt(qMax(xScale, yScale));
    return type == QTransform::TxRotate && qFuzzyCompare(xScale, yScale);
}

qt_static_shift()

template<int shift>

int qt_static_shift ( int  value )

inline

Definition at line 620 of file qpixmapfilter.cpp.

Referenced by qt_blurinner().

{
    if (shift == 0)
        return value;
    else if (shift > 0)
        return value << (uint(shift) & 0x1f);
    else
        return value >> (uint(-shift) & 0x1f);
}

Variable Documentation

alphaIndex

const int alphaIndex = (QSysInfo::ByteOrder == QSysInfo::BigEndian ? 0 : 3)

Definition at line 661 of file qpixmapfilter.cpp.

Referenced by qt_blurrow().

radiusScale

const qreal radiusScale = qreal(2.5)

Definition at line 607 of file qpixmapfilter.cpp.

Referenced by QPixmapBlurFilter::boundingRectFor(), and QPixmapBlurFilter::draw().