src/gui/image/qbmphandler.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gui/image/qbmphandler.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,833 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "private/qbmphandler_p.h"
+
+#ifndef QT_NO_IMAGEFORMAT_BMP
+
+#include <qimage.h>
+#include <qvariant.h>
+#include <qvector.h>
+
+QT_BEGIN_NAMESPACE
+
+static void swapPixel01(QImage *image)        // 1-bpp: swap 0 and 1 pixels
+{
+    int i;
+    if (image->depth() == 1 && image->numColors() == 2) {
+        register uint *p = (uint *)image->bits();
+        int nbytes = image->numBytes();
+        for (i=0; i<nbytes/4; i++) {
+            *p = ~*p;
+            p++;
+        }
+        uchar *p2 = (uchar *)p;
+        for (i=0; i<(nbytes&3); i++) {
+            *p2 = ~*p2;
+            p2++;
+        }
+        QRgb t = image->color(0);                // swap color 0 and 1
+        image->setColor(0, image->color(1));
+        image->setColor(1, t);
+    }
+}
+
+/*
+    QImageIO::defineIOHandler("BMP", "^BM", 0,
+                               read_bmp_image, write_bmp_image);
+*/
+
+/*****************************************************************************
+  BMP (DIB) image read/write functions
+ *****************************************************************************/
+
+const int BMP_FILEHDR_SIZE = 14;                // size of BMP_FILEHDR data
+
+static QDataStream &operator>>(QDataStream &s, BMP_FILEHDR &bf)
+{                                                // read file header
+    s.readRawData(bf.bfType, 2);
+    s >> bf.bfSize >> bf.bfReserved1 >> bf.bfReserved2 >> bf.bfOffBits;
+    return s;
+}
+
+static QDataStream &operator<<(QDataStream &s, const BMP_FILEHDR &bf)
+{                                                // write file header
+    s.writeRawData(bf.bfType, 2);
+    s << bf.bfSize << bf.bfReserved1 << bf.bfReserved2 << bf.bfOffBits;
+    return s;
+}
+
+
+const int BMP_OLD  = 12;                        // old Windows/OS2 BMP size
+const int BMP_WIN  = 40;                        // new Windows BMP size
+const int BMP_OS2  = 64;                        // new OS/2 BMP size
+
+const int BMP_RGB  = 0;                                // no compression
+const int BMP_RLE8 = 1;                                // run-length encoded, 8 bits
+const int BMP_RLE4 = 2;                                // run-length encoded, 4 bits
+const int BMP_BITFIELDS = 3;                        // RGB values encoded in data as bit-fields
+
+
+static QDataStream &operator>>(QDataStream &s, BMP_INFOHDR &bi)
+{
+    s >> bi.biSize;
+    if (bi.biSize == BMP_WIN || bi.biSize == BMP_OS2) {
+        s >> bi.biWidth >> bi.biHeight >> bi.biPlanes >> bi.biBitCount;
+        s >> bi.biCompression >> bi.biSizeImage;
+        s >> bi.biXPelsPerMeter >> bi.biYPelsPerMeter;
+        s >> bi.biClrUsed >> bi.biClrImportant;
+    }
+    else {                                        // probably old Windows format
+        qint16 w, h;
+        s >> w >> h >> bi.biPlanes >> bi.biBitCount;
+        bi.biWidth  = w;
+        bi.biHeight = h;
+        bi.biCompression = BMP_RGB;                // no compression
+        bi.biSizeImage = 0;
+        bi.biXPelsPerMeter = bi.biYPelsPerMeter = 0;
+        bi.biClrUsed = bi.biClrImportant = 0;
+    }
+    return s;
+}
+
+static QDataStream &operator<<(QDataStream &s, const BMP_INFOHDR &bi)
+{
+    s << bi.biSize;
+    s << bi.biWidth << bi.biHeight;
+    s << bi.biPlanes;
+    s << bi.biBitCount;
+    s << bi.biCompression;
+    s << bi.biSizeImage;
+    s << bi.biXPelsPerMeter << bi.biYPelsPerMeter;
+    s << bi.biClrUsed << bi.biClrImportant;
+    return s;
+}
+
+static int calc_shift(int mask)
+{
+    int result = 0;
+    while (!(mask & 1)) {
+        result++;
+        mask >>= 1;
+    }
+    return result;
+}
+
+static bool read_dib_fileheader(QDataStream &s, BMP_FILEHDR &bf)
+{
+    // read BMP file header
+    s >> bf;
+    if (s.status() != QDataStream::Ok)
+        return false;
+
+    // check header
+    if (qstrncmp(bf.bfType,"BM",2) != 0)
+        return false;
+
+    return true;
+}
+
+static bool read_dib_infoheader(QDataStream &s, BMP_INFOHDR &bi)
+{
+    s >> bi;                                        // read BMP info header
+    if (s.status() != QDataStream::Ok)
+        return false;
+
+    int nbits = bi.biBitCount;
+    int comp = bi.biCompression;
+    if (!(nbits == 1 || nbits == 4 || nbits == 8 || nbits == 16 || nbits == 24 || nbits == 32) ||
+        bi.biPlanes != 1 || comp > BMP_BITFIELDS)
+        return false;                                        // weird BMP image
+    if (!(comp == BMP_RGB || (nbits == 4 && comp == BMP_RLE4) ||
+        (nbits == 8 && comp == BMP_RLE8) || ((nbits == 16 || nbits == 32) && comp == BMP_BITFIELDS)))
+         return false;                                // weird compression type
+
+    return true;
+}
+
+static bool read_dib_body(QDataStream &s, const BMP_INFOHDR &bi, int offset, int startpos, QImage &image)
+{
+    QIODevice* d = s.device();
+    if (d->atEnd())                                // end of stream/file
+        return false;
+#if 0
+    qDebug("offset...........%d", offset);
+    qDebug("startpos.........%d", startpos);
+    qDebug("biSize...........%d", bi.biSize);
+    qDebug("biWidth..........%d", bi.biWidth);
+    qDebug("biHeight.........%d", bi.biHeight);
+    qDebug("biPlanes.........%d", bi.biPlanes);
+    qDebug("biBitCount.......%d", bi.biBitCount);
+    qDebug("biCompression....%d", bi.biCompression);
+    qDebug("biSizeImage......%d", bi.biSizeImage);
+    qDebug("biXPelsPerMeter..%d", bi.biXPelsPerMeter);
+    qDebug("biYPelsPerMeter..%d", bi.biYPelsPerMeter);
+    qDebug("biClrUsed........%d", bi.biClrUsed);
+    qDebug("biClrImportant...%d", bi.biClrImportant);
+#endif
+    int w = bi.biWidth,         h = bi.biHeight,  nbits = bi.biBitCount;
+    int t = bi.biSize,         comp = bi.biCompression;
+    int red_mask = 0;
+    int green_mask = 0;
+    int blue_mask = 0;
+    int red_shift = 0;
+    int green_shift = 0;
+    int blue_shift = 0;
+    int red_scale = 0;
+    int green_scale = 0;
+    int blue_scale = 0;
+
+    int ncols = 0;
+    int depth = 0;
+    QImage::Format format;
+    switch (nbits) {
+        case 32:
+        case 24:
+        case 16:
+            depth = 32;
+            format = QImage::Format_RGB32;
+            break;
+        case 8:
+        case 4:
+            depth = 8;
+            format = QImage::Format_Indexed8;
+            break;
+        default:
+            depth = 1;
+            format = QImage::Format_Mono;
+    }
+
+    if (bi.biHeight < 0)
+        h = -h;                  // support images with negative height
+
+    if (image.size() != QSize(w, h) || image.format() != format) {
+        image = QImage(w, h, format);
+        if (image.isNull())                        // could not create image
+            return false;
+    }
+
+    if (depth != 32) {
+        ncols = bi.biClrUsed ? bi.biClrUsed : 1 << nbits;
+        image.setNumColors(ncols);
+    }
+
+    image.setDotsPerMeterX(bi.biXPelsPerMeter);
+    image.setDotsPerMeterY(bi.biYPelsPerMeter);
+
+    if (!d->isSequential())
+        d->seek(startpos + BMP_FILEHDR_SIZE + bi.biSize); // goto start of colormap
+
+    if (ncols > 0) {                                // read color table
+        uchar rgb[4];
+        int   rgb_len = t == BMP_OLD ? 3 : 4;
+        for (int i=0; i<ncols; i++) {
+            if (d->read((char *)rgb, rgb_len) != rgb_len)
+                return false;
+            image.setColor(i, qRgb(rgb[2],rgb[1],rgb[0]));
+            if (d->atEnd())                        // truncated file
+                return false;
+        }
+    } else if (comp == BMP_BITFIELDS && (nbits == 16 || nbits == 32)) {
+        if (d->read((char *)&red_mask, sizeof(red_mask)) != sizeof(red_mask))
+            return false;
+        if (d->read((char *)&green_mask, sizeof(green_mask)) != sizeof(green_mask))
+            return false;
+        if (d->read((char *)&blue_mask, sizeof(blue_mask)) != sizeof(blue_mask))
+            return false;
+        red_shift = calc_shift(red_mask);
+        red_scale = 256 / ((red_mask >> red_shift) + 1);
+        green_shift = calc_shift(green_mask);
+        green_scale = 256 / ((green_mask >> green_shift) + 1);
+        blue_shift = calc_shift(blue_mask);
+        blue_scale = 256 / ((blue_mask >> blue_shift) + 1);
+    } else if (comp == BMP_RGB && (nbits == 24 || nbits == 32)) {
+        blue_mask = 0x000000ff;
+        green_mask = 0x0000ff00;
+        red_mask = 0x00ff0000;
+        blue_shift = 0;
+        green_shift = 8;
+        red_shift = 16;
+        blue_scale = green_scale = red_scale = 1;
+    } else if (comp == BMP_RGB && nbits == 16) {
+        blue_mask = 0x001f;
+        green_mask = 0x03e0;
+        red_mask = 0x7c00;
+        blue_shift = 0;
+        green_shift = 2;
+        red_shift = 7;
+        red_scale = 1;
+        green_scale = 1;
+        blue_scale = 8;
+    }
+
+    // offset can be bogus, be careful
+    if (offset>=0 && startpos + offset > d->pos()) {
+        if (!d->isSequential())
+            d->seek(startpos + offset);                // start of image data
+    }
+
+    int             bpl = image.bytesPerLine();
+    uchar *data = image.bits();
+
+    if (nbits == 1) {                                // 1 bit BMP image
+        while (--h >= 0) {
+            if (d->read((char*)(data + h*bpl), bpl) != bpl)
+                break;
+        }
+        if (ncols == 2 && qGray(image.color(0)) < qGray(image.color(1)))
+            swapPixel01(&image);                // pixel 0 is white!
+    }
+
+    else if (nbits == 4) {                        // 4 bit BMP image
+        int    buflen = ((w+7)/8)*4;
+        uchar *buf    = new uchar[buflen];
+        if (comp == BMP_RLE4) {                // run length compression
+            int x=0, y=0, c, i;
+            quint8 b;
+            register uchar *p = data + (h-1)*bpl;
+            const uchar *endp = p + w;
+            while (y < h) {
+                if (!d->getChar((char *)&b))
+                    break;
+                if (b == 0) {                        // escape code
+                    if (!d->getChar((char *)&b) || b == 1) {
+                        y = h;                // exit loop
+                    } else switch (b) {
+                        case 0:                        // end of line
+                            x = 0;
+                            y++;
+                            p = data + (h-y-1)*bpl;
+                            break;
+                        case 2:                        // delta (jump)
+                        {
+                            quint8 tmp;
+                            d->getChar((char *)&tmp);
+                            x += tmp;
+                            d->getChar((char *)&tmp);
+                            y += tmp;
+                        }
+
+                            // Protection
+                            if ((uint)x >= (uint)w)
+                                x = w-1;
+                            if ((uint)y >= (uint)h)
+                                y = h-1;
+
+                            p = data + (h-y-1)*bpl + x;
+                            break;
+                        default:                // absolute mode
+                            // Protection
+                            if (p + b > endp)
+                                b = endp-p;
+
+                            i = (c = b)/2;
+                            while (i--) {
+                                d->getChar((char *)&b);
+                                *p++ = b >> 4;
+                                *p++ = b & 0x0f;
+                            }
+                            if (c & 1) {
+                                unsigned char tmp;
+                                d->getChar((char *)&tmp);
+                                *p++ = tmp >> 4;
+                            }
+                            if ((((c & 3) + 1) & 2) == 2)
+                                d->getChar(0);        // align on word boundary
+                            x += c;
+                    }
+                } else {                        // encoded mode
+                    // Protection
+                    if (p + b > endp)
+                        b = endp-p;
+
+                    i = (c = b)/2;
+                    d->getChar((char *)&b);                // 2 pixels to be repeated
+                    while (i--) {
+                        *p++ = b >> 4;
+                        *p++ = b & 0x0f;
+                    }
+                    if (c & 1)
+                        *p++ = b >> 4;
+                    x += c;
+                }
+            }
+        } else if (comp == BMP_RGB) {                // no compression
+            memset(data, 0, h*bpl);
+            while (--h >= 0) {
+                if (d->read((char*)buf,buflen) != buflen)
+                    break;
+                register uchar *p = data + h*bpl;
+                uchar *b = buf;
+                for (int i=0; i<w/2; i++) {        // convert nibbles to bytes
+                    *p++ = *b >> 4;
+                    *p++ = *b++ & 0x0f;
+                }
+                if (w & 1)                        // the last nibble
+                    *p = *b >> 4;
+            }
+        }
+        delete [] buf;
+    }
+
+    else if (nbits == 8) {                        // 8 bit BMP image
+        if (comp == BMP_RLE8) {                // run length compression
+            int x=0, y=0;
+            quint8 b;
+            register uchar *p = data + (h-1)*bpl;
+            const uchar *endp = p + w;
+            while (y < h) {
+                if (!d->getChar((char *)&b))
+                    break;
+                if (b == 0) {                        // escape code
+                    if (!d->getChar((char *)&b) || b == 1) {
+                            y = h;                // exit loop
+                    } else switch (b) {
+                        case 0:                        // end of line
+                            x = 0;
+                            y++;
+                            p = data + (h-y-1)*bpl;
+                            break;
+                        case 2:                        // delta (jump)
+                            // Protection
+                            if ((uint)x >= (uint)w)
+                                x = w-1;
+                            if ((uint)y >= (uint)h)
+                                y = h-1;
+
+                            {
+                                quint8 tmp;
+                                d->getChar((char *)&tmp);
+                                x += tmp;
+                                d->getChar((char *)&tmp);
+                                y += tmp;
+                            }
+                            p = data + (h-y-1)*bpl + x;
+                            break;
+                        default:                // absolute mode
+                            // Protection
+                            if (p + b > endp)
+                                b = endp-p;
+
+                            if (d->read((char *)p, b) != b)
+                                return false;
+                            if ((b & 1) == 1)
+                                d->getChar(0);        // align on word boundary
+                            x += b;
+                            p += b;
+                    }
+                } else {                        // encoded mode
+                    // Protection
+                    if (p + b > endp)
+                        b = endp-p;
+
+                    char tmp;
+                    d->getChar(&tmp);
+                    memset(p, tmp, b); // repeat pixel
+                    x += b;
+                    p += b;
+                }
+            }
+        } else if (comp == BMP_RGB) {                // uncompressed
+            while (--h >= 0) {
+                if (d->read((char *)data + h*bpl, bpl) != bpl)
+                    break;
+            }
+        }
+    }
+
+    else if (nbits == 16 || nbits == 24 || nbits == 32) { // 16,24,32 bit BMP image
+        register QRgb *p;
+        QRgb  *end;
+        uchar *buf24 = new uchar[bpl];
+        int    bpl24 = ((w*nbits+31)/32)*4;
+        uchar *b;
+        int c;
+
+        while (--h >= 0) {
+            p = (QRgb *)(data + h*bpl);
+            end = p + w;
+            if (d->read((char *)buf24,bpl24) != bpl24)
+                break;
+            b = buf24;
+            while (p < end) {
+                c = *(uchar*)b | (*(uchar*)(b+1)<<8);
+                if (nbits != 16)
+                    c |= *(uchar*)(b+2)<<16;
+                *p++ = qRgb(((c & red_mask) >> red_shift) * red_scale,
+                                        ((c & green_mask) >> green_shift) * green_scale,
+                                        ((c & blue_mask) >> blue_shift) * blue_scale);
+                b += nbits/8;
+            }
+        }
+        delete[] buf24;
+    }
+
+    if (bi.biHeight < 0) {
+        // Flip the image
+        uchar *buf = new uchar[bpl];
+        h = -bi.biHeight;
+        for (int y = 0; y < h/2; ++y) {
+            memcpy(buf, data + y*bpl, bpl);
+            memcpy(data + y*bpl, data + (h-y-1)*bpl, bpl);
+            memcpy(data + (h-y-1)*bpl, buf, bpl);
+        }
+        delete [] buf;
+    }
+
+    return true;
+}
+
+// this is also used in qmime_win.cpp
+bool qt_write_dib(QDataStream &s, QImage image)
+{
+    int        nbits;
+    int        bpl_bmp;
+    int        bpl = image.bytesPerLine();
+
+    QIODevice* d = s.device();
+    if (!d->isWritable())
+        return false;
+
+    if (image.depth() == 8 && image.numColors() <= 16) {
+        bpl_bmp = (((bpl+1)/2+3)/4)*4;
+        nbits = 4;
+    } else if (image.depth() == 32) {
+        bpl_bmp = ((image.width()*24+31)/32)*4;
+        nbits = 24;
+#ifdef Q_WS_QWS
+    } else if (image.depth() == 1 || image.depth() == 8) {
+        // Qt for Embedded Linux doesn't word align.
+        bpl_bmp = ((image.width()*image.depth()+31)/32)*4;
+        nbits = image.depth();
+#endif
+    } else {
+        bpl_bmp = bpl;
+        nbits = image.depth();
+    }
+
+    BMP_INFOHDR bi;
+    bi.biSize               = BMP_WIN;                // build info header
+    bi.biWidth               = image.width();
+    bi.biHeight               = image.height();
+    bi.biPlanes               = 1;
+    bi.biBitCount      = nbits;
+    bi.biCompression   = BMP_RGB;
+    bi.biSizeImage     = bpl_bmp*image.height();
+    bi.biXPelsPerMeter = image.dotsPerMeterX() ? image.dotsPerMeterX()
+                                                : 2834; // 72 dpi default
+    bi.biYPelsPerMeter = image.dotsPerMeterY() ? image.dotsPerMeterY() : 2834;
+    bi.biClrUsed       = image.numColors();
+    bi.biClrImportant  = image.numColors();
+    s << bi;                                        // write info header
+    if (s.status() != QDataStream::Ok)
+        return false;
+
+    if (image.depth() != 32) {                // write color table
+        uchar *color_table = new uchar[4*image.numColors()];
+        uchar *rgb = color_table;
+        QVector<QRgb> c = image.colorTable();
+        for (int i=0; i<image.numColors(); i++) {
+            *rgb++ = qBlue (c[i]);
+            *rgb++ = qGreen(c[i]);
+            *rgb++ = qRed  (c[i]);
+            *rgb++ = 0;
+        }
+        if (d->write((char *)color_table, 4*image.numColors()) == -1) {
+            delete [] color_table;
+            return false;
+        }
+        delete [] color_table;
+    }
+
+    if (image.format() == QImage::Format_MonoLSB)
+        image = image.convertToFormat(QImage::Format_Mono);
+
+    int y;
+
+    if (nbits == 1 || nbits == 8) {                // direct output
+#ifdef Q_WS_QWS
+        // Qt for Embedded Linux doesn't word align.
+        int pad = bpl_bmp - bpl;
+        char padding[4];
+#endif
+        for (y=image.height()-1; y>=0; y--) {
+            if (d->write((char*)image.scanLine(y), bpl) == -1)
+                return false;
+#ifdef Q_WS_QWS
+            if (d->write(padding, pad) == -1)
+                return false;
+#endif
+        }
+        return true;
+    }
+
+    uchar *buf        = new uchar[bpl_bmp];
+    uchar *b, *end;
+    register uchar *p;
+
+    memset(buf, 0, bpl_bmp);
+    for (y=image.height()-1; y>=0; y--) {        // write the image bits
+        if (nbits == 4) {                        // convert 8 -> 4 bits
+            p = image.scanLine(y);
+            b = buf;
+            end = b + image.width()/2;
+            while (b < end) {
+                *b++ = (*p << 4) | (*(p+1) & 0x0f);
+                p += 2;
+            }
+            if (image.width() & 1)
+                *b = *p << 4;
+        } else {                                // 32 bits
+            QRgb *p   = (QRgb *)image.scanLine(y);
+            QRgb *end = p + image.width();
+            b = buf;
+            while (p < end) {
+                *b++ = qBlue(*p);
+                *b++ = qGreen(*p);
+                *b++ = qRed(*p);
+                p++;
+            }
+        }
+        if (bpl_bmp != d->write((char*)buf, bpl_bmp)) {
+            delete[] buf;
+            return false;
+        }
+    }
+    delete[] buf;
+    return true;
+}
+
+// this is also used in qmime_win.cpp
+bool qt_read_dib(QDataStream &s, QImage &image)
+{
+    BMP_INFOHDR bi;
+    if (!read_dib_infoheader(s, bi))
+        return false;
+    return read_dib_body(s, bi, -1, -BMP_FILEHDR_SIZE, image);
+}
+
+QBmpHandler::QBmpHandler()
+    : state(Ready)
+{
+}
+
+bool QBmpHandler::readHeader()
+{
+    state = Error;
+
+    QIODevice *d = device();
+    QDataStream s(d);
+    startpos = d->pos();
+
+    // Intel byte order
+    s.setByteOrder(QDataStream::LittleEndian);
+
+    // read BMP file header
+    if (!read_dib_fileheader(s, fileHeader))
+        return false;
+
+    // read BMP info header
+    if (!read_dib_infoheader(s, infoHeader))
+        return false;
+
+    state = ReadHeader;
+    return true;
+}
+
+bool QBmpHandler::canRead() const
+{
+    if (state == Ready) {
+        if (!canRead(device()))
+            return false;
+        setFormat("bmp");
+        return true;
+    }
+    return state != Error;
+}
+
+bool QBmpHandler::canRead(QIODevice *device)
+{
+    if (!device) {
+        qWarning("QBmpHandler::canRead() called with 0 pointer");
+        return false;
+    }
+
+    char head[2];
+    if (device->peek(head, sizeof(head)) != sizeof(head))
+        return false;
+
+    return (qstrncmp(head, "BM", 2) == 0);
+}
+
+bool QBmpHandler::read(QImage *image)
+{
+    if (state == Error)
+        return false;
+
+    if (!image) {
+        qWarning("QBmpHandler::read: cannot read into null pointer");
+        return false;
+    }
+
+    if (state == Ready && !readHeader()) {
+        state = Error;
+        return false;
+    }
+
+    QIODevice *d = device();
+    QDataStream s(d);
+
+    // Intel byte order
+    s.setByteOrder(QDataStream::LittleEndian);
+
+    // read image
+    if (!read_dib_body(s, infoHeader, fileHeader.bfOffBits, startpos, *image))
+        return false;
+
+    state = Ready;
+    return true;
+}
+
+bool QBmpHandler::write(const QImage &img)
+{
+    QImage image;
+    switch (img.format()) {
+    case QImage::Format_ARGB8565_Premultiplied:
+    case QImage::Format_ARGB8555_Premultiplied:
+    case QImage::Format_ARGB6666_Premultiplied:
+    case QImage::Format_ARGB4444_Premultiplied:
+        image = img.convertToFormat(QImage::Format_ARGB32);
+        break;
+    case QImage::Format_RGB16:
+    case QImage::Format_RGB888:
+    case QImage::Format_RGB666:
+    case QImage::Format_RGB555:
+    case QImage::Format_RGB444:
+        image = img.convertToFormat(QImage::Format_RGB32);
+        break;
+    default:
+        image = img;
+    }
+
+    QIODevice *d = device();
+    QDataStream s(d);
+    BMP_FILEHDR bf;
+    int bpl_bmp;
+    int bpl = image.bytesPerLine();
+
+    // Code partially repeated in qt_write_dib
+    if (image.depth() == 8 && image.numColors() <= 16) {
+        bpl_bmp = (((bpl+1)/2+3)/4)*4;
+    } else if (image.depth() == 32) {
+        bpl_bmp = ((image.width()*24+31)/32)*4;
+    } else {
+        bpl_bmp = bpl;
+    }
+
+    // Intel byte order
+    s.setByteOrder(QDataStream::LittleEndian);
+
+    // build file header
+    memcpy(bf.bfType, "BM", 2);
+
+    // write file header
+    bf.bfReserved1 = 0;
+    bf.bfReserved2 = 0;
+    bf.bfOffBits = BMP_FILEHDR_SIZE + BMP_WIN + image.numColors() * 4;
+    bf.bfSize = bf.bfOffBits + bpl_bmp*image.height();
+    s << bf;
+
+    // write image
+    return qt_write_dib(s, image);
+}
+
+bool QBmpHandler::supportsOption(ImageOption option) const
+{
+    return option == Size
+            || option == ImageFormat;
+}
+
+QVariant QBmpHandler::option(ImageOption option) const
+{
+    if (option == Size) {
+        if (state == Error)
+            return QVariant();
+        if (state == Ready && !const_cast<QBmpHandler*>(this)->readHeader())
+            return QVariant();
+        return QSize(infoHeader.biWidth, infoHeader.biHeight);
+    } else if (option == ImageFormat) {
+        if (state == Error)
+            return QVariant();
+        if (state == Ready && !const_cast<QBmpHandler*>(this)->readHeader())
+            return QVariant();
+        QImage::Format format;
+        switch (infoHeader.biBitCount) {
+            case 32:
+            case 24:
+            case 16:
+                format = QImage::Format_RGB32;
+                break;
+            case 8:
+            case 4:
+                format = QImage::Format_Indexed8;
+                break;
+            default:
+                format = QImage::Format_Mono;
+            }
+        return format;
+    }
+    return QVariant();
+}
+
+void QBmpHandler::setOption(ImageOption option, const QVariant &value)
+{
+    Q_UNUSED(option);
+    Q_UNUSED(value);
+}
+
+QByteArray QBmpHandler::name() const
+{
+    return "bmp";
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_IMAGEFORMAT_BMP