// Copyright (C) 2022 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 /*! \class QtIcoHandler \since 4.4 \brief The QtIcoHandler class provides support for the ICO image format. \internal */ #include "qicohandler.h" #include #include #include #include #include #include #include QT_BEGIN_NAMESPACE Q_LOGGING_CATEGORY(lcIco, "qt.gui.imageio.ico") namespace { // These next two structs represent how the icon information is stored // in an ICO file. typedef struct { quint8 bWidth; // Width of the image quint8 bHeight; // Height of the image (actual height, not times 2) quint8 bColorCount; // Number of colors in image (0 if >=8bpp) [ not ture ] quint8 bReserved; // Reserved quint16_le wPlanes; // Color Planes quint16_le wBitCount; // Bits per pixel quint32_le dwBytesInRes; // how many bytes in this resource? quint32_le dwImageOffset; // where in the file is this image } ICONDIRENTRY, *LPICONDIRENTRY; #define ICONDIRENTRY_SIZE 16 typedef struct { quint16_le idReserved; // Reserved quint16_le idType; // resource type (1 for icons, 2 for cursors) quint16_le idCount; // how many images? ICONDIRENTRY idEntries[1]; // the entries for each image } ICONDIR, *LPICONDIR; #define ICONDIR_SIZE 6 // Exclude the idEntries field typedef struct { // BMP information header quint32_le biSize; // size of this struct quint32_le biWidth; // pixmap width quint32_le biHeight; // pixmap height (specifies the combined height of the XOR and AND masks) quint16_le biPlanes; // should be 1 quint16_le biBitCount; // number of bits per pixel quint32_le biCompression; // compression method quint32_le biSizeImage; // size of image quint32_le biXPelsPerMeter; // horizontal resolution quint32_le biYPelsPerMeter; // vertical resolution quint32_le biClrUsed; // number of colors used quint32_le biClrImportant; // number of important colors } BMP_INFOHDR ,*LPBMP_INFOHDR; #define BMP_INFOHDR_SIZE 40 } class ICOReader { public: ICOReader(QIODevice * iodevice); int count(); QImage iconAt(int index); static bool canRead(QIODevice *iodev); static QList read(QIODevice *device); static bool write(QIODevice *device, const QList &images); bool readIconEntry(int index, ICONDIRENTRY * iconEntry); private: bool readHeader(); bool readBMPHeader(quint32 imageOffset, BMP_INFOHDR * header); void findColorInfo(QImage & image); void readColorTable(QImage & image); void readBMP(QImage & image); void read1BitBMP(QImage & image); void read4BitBMP(QImage & image); void read8BitBMP(QImage & image); void read16_24_32BMP(QImage & image); struct IcoAttrib { int nbits; int ncolors; int h; int w; int depth; } icoAttrib; QIODevice * iod; qint64 startpos; bool headerRead; ICONDIR iconDir; }; // Data readers and writers that takes care of alignment and endian stuff. static bool readIconDirEntry(QIODevice *iodev, ICONDIRENTRY *iconDirEntry) { if (iodev) return (iodev->read((char*)iconDirEntry, ICONDIRENTRY_SIZE) == ICONDIRENTRY_SIZE); return false; } static bool writeIconDirEntry(QIODevice *iodev, const ICONDIRENTRY &iconEntry) { if (iodev) return iodev->write((char*)&iconEntry, ICONDIRENTRY_SIZE) == ICONDIRENTRY_SIZE; return false; } static bool readIconDir(QIODevice *iodev, ICONDIR *iconDir) { if (iodev) return (iodev->read((char*)iconDir, ICONDIR_SIZE) == ICONDIR_SIZE); return false; } static bool writeIconDir(QIODevice *iodev, const ICONDIR &iconDir) { if (iodev) return iodev->write((char*)&iconDir, 6) == 6; return false; } static bool readBMPInfoHeader(QIODevice *iodev, BMP_INFOHDR *pHeader) { if (iodev) return (iodev->read((char*)pHeader, BMP_INFOHDR_SIZE) == BMP_INFOHDR_SIZE); return false; } static bool writeBMPInfoHeader(QIODevice *iodev, const BMP_INFOHDR &header) { if (iodev) return iodev->write((char*)&header, BMP_INFOHDR_SIZE) == BMP_INFOHDR_SIZE; return false; } ICOReader::ICOReader(QIODevice * iodevice) : iod(iodevice) , startpos(0) , headerRead(false) { } int ICOReader::count() { if (readHeader()) return iconDir.idCount; return 0; } bool ICOReader::canRead(QIODevice *iodev) { bool isProbablyICO = false; if (iodev) { qint64 oldPos = iodev->pos(); ICONDIR ikonDir; if (readIconDir(iodev, &ikonDir)) { if (readIconDirEntry(iodev, &ikonDir.idEntries[0])) { // ICO format does not have a magic identifier, so we read 6 different values, which will hopefully be enough to identify the file. if ( ikonDir.idReserved == 0 && (ikonDir.idType == 1 || ikonDir.idType == 2) && ikonDir.idEntries[0].bReserved == 0 && (ikonDir.idEntries[0].wPlanes <= 1 || ikonDir.idType == 2) && (ikonDir.idEntries[0].wBitCount <= 32 || ikonDir.idType == 2) // Bits per pixel && ikonDir.idEntries[0].dwBytesInRes >= 40 // Must be over 40, since sizeof (infoheader) == 40 ) { isProbablyICO = true; } if (iodev->isSequential()) { // Our structs might be padded due to alignment, so we need to fetch each member before we ungetChar() ! quint32 tmp = ikonDir.idEntries[0].dwImageOffset; iodev->ungetChar((tmp >> 24) & 0xff); iodev->ungetChar((tmp >> 16) & 0xff); iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); tmp = ikonDir.idEntries[0].dwBytesInRes; iodev->ungetChar((tmp >> 24) & 0xff); iodev->ungetChar((tmp >> 16) & 0xff); iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); tmp = ikonDir.idEntries[0].wBitCount; iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); tmp = ikonDir.idEntries[0].wPlanes; iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); iodev->ungetChar(ikonDir.idEntries[0].bReserved); iodev->ungetChar(ikonDir.idEntries[0].bColorCount); iodev->ungetChar(ikonDir.idEntries[0].bHeight); iodev->ungetChar(ikonDir.idEntries[0].bWidth); } } if (iodev->isSequential()) { // Our structs might be padded due to alignment, so we need to fetch each member before we ungetChar() ! quint32 tmp = ikonDir.idCount; iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); tmp = ikonDir.idType; iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); tmp = ikonDir.idReserved; iodev->ungetChar((tmp >> 8) & 0xff); iodev->ungetChar(tmp & 0xff); } } if (!iodev->isSequential()) iodev->seek(oldPos); } return isProbablyICO; } bool ICOReader::readHeader() { if (iod && !headerRead) { startpos = iod->pos(); if (readIconDir(iod, &iconDir)) { if (iconDir.idReserved == 0 && (iconDir.idType == 1 || iconDir.idType == 2)) headerRead = true; } } return headerRead; } bool ICOReader::readIconEntry(int index, ICONDIRENTRY *iconEntry) { if (readHeader()) { if (iod->seek(startpos + ICONDIR_SIZE + (index * ICONDIRENTRY_SIZE))) { return readIconDirEntry(iod, iconEntry); } } return false; } bool ICOReader::readBMPHeader(quint32 imageOffset, BMP_INFOHDR * header) { if (iod) { if (iod->seek(startpos + imageOffset)) { if (readBMPInfoHeader(iod, header)) { return true; } } } return false; } void ICOReader::findColorInfo(QImage & image) { if (icoAttrib.ncolors > 0) { // set color table readColorTable(image); } else if (icoAttrib.nbits == 16) { // don't support RGB values for 15/16 bpp image = QImage(); } } void ICOReader::readColorTable(QImage & image) { if (iod) { image.setColorCount(icoAttrib.ncolors); uchar rgb[4]; for (int i=0; iread((char*)rgb, 4) != 4) { image = QImage(); break; } image.setColor(i, qRgb(rgb[2],rgb[1],rgb[0])); } } else { image = QImage(); } } void ICOReader::readBMP(QImage & image) { if (icoAttrib.nbits == 1) { // 1 bit BMP image read1BitBMP(image); } else if (icoAttrib.nbits == 4) { // 4 bit BMP image read4BitBMP(image); } else if (icoAttrib.nbits == 8) { read8BitBMP(image); } else if (icoAttrib.nbits == 16 || icoAttrib.nbits == 24 || icoAttrib.nbits == 32 ) { // 16,24,32 bit BMP image read16_24_32BMP(image); } } /** * NOTE: A 1 bit BMP is only flipped vertically, and not horizontally like all other color depths! * (This is the same with the bitmask) * */ void ICOReader::read1BitBMP(QImage & image) { if (iod) { int h = image.height(); qsizetype bpl = image.bytesPerLine(); while (--h >= 0) { if (iod->read((char*)image.scanLine(h),bpl) != bpl) { image = QImage(); break; } } } else { image = QImage(); } } void ICOReader::read4BitBMP(QImage & image) { if (iod) { int h = icoAttrib.h; int buflen = ((icoAttrib.w+7)/8)*4; uchar *buf = new uchar[buflen]; Q_CHECK_PTR(buf); while (--h >= 0) { if (iod->read((char*)buf,buflen) != buflen) { image = QImage(); break; } uchar *p = image.scanLine(h); uchar *b = buf; for (int i=0; i> 4; *p++ = *b++ & 0x0f; } if (icoAttrib.w & 1) // the last nibble *p = *b >> 4; } delete [] buf; } else { image = QImage(); } } void ICOReader::read8BitBMP(QImage & image) { if (iod) { int h = icoAttrib.h; qsizetype bpl = image.bytesPerLine(); while (--h >= 0) { if (iod->read((char *)image.scanLine(h), bpl) != bpl) { image = QImage(); break; } } } else { image = QImage(); } } void ICOReader::read16_24_32BMP(QImage & image) { if (iod) { int h = icoAttrib.h; QRgb *p; QRgb *end; uchar *buf = new uchar[image.bytesPerLine()]; qsizetype bpl = ((qsizetype(icoAttrib.w)*icoAttrib.nbits+31)/32)*4; uchar *b; while (--h >= 0) { p = (QRgb *)image.scanLine(h); end = p + icoAttrib.w; if (iod->read((char *)buf, bpl) != bpl) { image = QImage(); break; } b = buf; while (p < end) { if (icoAttrib.nbits == 24) *p++ = qRgb(*(b+2), *(b+1), *b); else if (icoAttrib.nbits == 32) *p++ = qRgba(*(b+2), *(b+1), *b, *(b+3)); b += icoAttrib.nbits/8; } } delete[] buf; } else { image = QImage(); } } static const char icoOrigDepthKey[] = "_q_icoOrigDepth"; QImage ICOReader::iconAt(int index) { QImage img; if (count() > index) { // forces header to be read ICONDIRENTRY iconEntry; if (readIconEntry(index, &iconEntry)) { static const uchar pngMagicData[] = { 137, 80, 78, 71, 13, 10, 26, 10 }; if (!iod->seek(iconEntry.dwImageOffset) || iconEntry.dwBytesInRes > iod->bytesAvailable()) return img; const QByteArray pngMagic = QByteArray::fromRawData((const char*)pngMagicData, sizeof(pngMagicData)); const bool isPngImage = (iod->read(pngMagic.size()) == pngMagic); if (isPngImage) { iod->seek(iconEntry.dwImageOffset); QImage image = QImage::fromData(iod->read(iconEntry.dwBytesInRes), "png"); image.setText(QLatin1String(icoOrigDepthKey), QString::number(iconEntry.wBitCount)); return image; } BMP_INFOHDR header; if (readBMPHeader(iconEntry.dwImageOffset, &header)) { icoAttrib.nbits = header.biBitCount ? header.biBitCount : iconEntry.wBitCount; switch (icoAttrib.nbits) { case 32: case 24: case 16: icoAttrib.depth = 32; break; case 8: case 4: icoAttrib.depth = 8; break; case 1: icoAttrib.depth = 1; break; default: return img; break; } if (icoAttrib.depth == 32) // there's no colormap icoAttrib.ncolors = 0; else // # colors used icoAttrib.ncolors = header.biClrUsed ? uint(header.biClrUsed) : 1 << icoAttrib.nbits; if (icoAttrib.ncolors > 256) //color table can't be more than 256 return img; icoAttrib.w = iconEntry.bWidth; if (icoAttrib.w == 0) // means 256 pixels icoAttrib.w = header.biWidth; icoAttrib.h = iconEntry.bHeight; if (icoAttrib.h == 0) // means 256 pixels icoAttrib.h = header.biHeight/2; if (icoAttrib.w > 256 || icoAttrib.h > 256) // Max ico size return img; QImage::Format format = QImage::Format_ARGB32; if (icoAttrib.nbits == 24) format = QImage::Format_RGB32; else if (icoAttrib.ncolors == 2 && icoAttrib.depth == 1) format = QImage::Format_Mono; else if (icoAttrib.ncolors > 0) format = QImage::Format_Indexed8; QImage image; const QSize size(icoAttrib.w, icoAttrib.h); if (QImageIOHandler::allocateImage(size, format, &image)) { findColorInfo(image); if (!image.isNull()) { readBMP(image); if (!image.isNull()) { if (icoAttrib.nbits == 32) { img = std::move(image).convertToFormat(QImage::Format_ARGB32_Premultiplied); } else { QImage mask(image.width(), image.height(), QImage::Format_Mono); if (!mask.isNull()) { mask.setColorCount(2); mask.setColor(0, qRgba(255,255,255,0xff)); mask.setColor(1, qRgba(0 ,0 ,0 ,0xff)); read1BitBMP(mask); if (!mask.isNull()) { img = image; img.setAlphaChannel(mask); } } } } } } img.setText(QLatin1String(icoOrigDepthKey), QString::number(iconEntry.wBitCount)); } } } return img; } /*! Reads all the icons from the given \a device, and returns them as a list of QImage objects. Each image has an alpha channel that represents the mask from the corresponding icon. \sa write() */ QList ICOReader::read(QIODevice *device) { QList images; ICOReader reader(device); const int N = reader.count(); images.reserve(N); for (int i = 0; i < N; i++) images += reader.iconAt(i); return images; } /*! Writes all the QImages in the \a images list to the given \a device. Returns \c true if the images are written successfully; otherwise returns \c false. The first image in the list is stored as the first icon in the device, and is therefore used as the default icon by applications. The alpha channel of each image is converted to a mask for each corresponding icon. \sa read() */ bool ICOReader::write(QIODevice *device, const QList &images) { bool retValue = false; if (images.size()) { qint64 origOffset = device->pos(); ICONDIR id; id.idReserved = 0; id.idType = 1; id.idCount = images.size(); ICONDIRENTRY * entries = new ICONDIRENTRY[id.idCount]; BMP_INFOHDR * bmpHeaders = new BMP_INFOHDR[id.idCount]; QByteArray * imageData = new QByteArray[id.idCount]; for (int i=0; i 256 || image.height() > 256) { image = image.scaled(256, 256, Qt::KeepAspectRatio, Qt::SmoothTransformation); } QImage maskImage(image.width(), image.height(), QImage::Format_Mono); image = image.convertToFormat(QImage::Format_ARGB32); maskImage.fill(Qt::color1); int nbits = 32; int bpl_bmp = ((image.width()*nbits+31)/32)*4; entries[i].bColorCount = 0; entries[i].bReserved = 0; entries[i].wBitCount = nbits; entries[i].bHeight = image.height() < 256 ? image.height() : 0; // 0 means 256 entries[i].bWidth = image.width() < 256 ? image.width() : 0; // 0 means 256 entries[i].dwBytesInRes = BMP_INFOHDR_SIZE + (bpl_bmp * image.height()) + (maskImage.bytesPerLine() * maskImage.height()); entries[i].wPlanes = 1; if (i == 0) entries[i].dwImageOffset = origOffset + ICONDIR_SIZE + (id.idCount * ICONDIRENTRY_SIZE); else entries[i].dwImageOffset = entries[i-1].dwImageOffset + entries[i-1].dwBytesInRes; bmpHeaders[i].biBitCount = entries[i].wBitCount; bmpHeaders[i].biClrImportant = 0; bmpHeaders[i].biClrUsed = entries[i].bColorCount; bmpHeaders[i].biCompression = 0; bmpHeaders[i].biHeight = entries[i].bHeight ? entries[i].bHeight * 2 : 256 * 2; // 2 is for the mask bmpHeaders[i].biPlanes = entries[i].wPlanes; bmpHeaders[i].biSize = BMP_INFOHDR_SIZE; bmpHeaders[i].biSizeImage = entries[i].dwBytesInRes - BMP_INFOHDR_SIZE; bmpHeaders[i].biWidth = entries[i].bWidth ? entries[i].bWidth : 256; bmpHeaders[i].biXPelsPerMeter = 0; bmpHeaders[i].biYPelsPerMeter = 0; QBuffer buffer(&imageData[i]); buffer.open(QIODevice::WriteOnly); uchar *buf = new uchar[bpl_bmp]; uchar *b; memset( buf, 0, bpl_bmp ); int y; for (y = image.height() - 1; y >= 0; y--) { // write the image bits // 32 bits QRgb *p = (QRgb *)image.scanLine(y); QRgb *end = p + image.width(); b = buf; int x = 0; while (p < end) { *b++ = qBlue(*p); *b++ = qGreen(*p); *b++ = qRed(*p); *b++ = qAlpha(*p); if (qAlpha(*p) > 0) // Even mostly transparent pixels must not be masked away maskImage.setPixel(x, y, 0); p++; x++; } buffer.write((char*)buf, bpl_bmp); } delete[] buf; // NOTE! !! The mask is only flipped vertically - not horizontally !! for (y = maskImage.height() - 1; y >= 0; y--) buffer.write((char*)maskImage.scanLine(y), maskImage.bytesPerLine()); } if (writeIconDir(device, id)) { int i; bool bOK = true; for (i = 0; i < id.idCount && bOK; i++) { bOK = writeIconDirEntry(device, entries[i]); } if (bOK) { for (i = 0; i < id.idCount && bOK; i++) { bOK = writeBMPInfoHeader(device, bmpHeaders[i]); bOK &= (device->write(imageData[i]) == (int) imageData[i].size()); } retValue = bOK; } } delete [] entries; delete [] bmpHeaders; delete [] imageData; } return retValue; } /*! Constructs an instance of QtIcoHandler initialized to use \a device. */ QtIcoHandler::QtIcoHandler(QIODevice *device) { m_currentIconIndex = 0; setDevice(device); m_pICOReader = new ICOReader(device); } /*! Destructor for QtIcoHandler. */ QtIcoHandler::~QtIcoHandler() { delete m_pICOReader; } QVariant QtIcoHandler::option(ImageOption option) const { if (option == Size || option == ImageFormat) { ICONDIRENTRY iconEntry; if (m_pICOReader->readIconEntry(m_currentIconIndex, &iconEntry)) { switch (option) { case Size: return QSize(iconEntry.bWidth ? iconEntry.bWidth : 256, iconEntry.bHeight ? iconEntry.bHeight : 256); case ImageFormat: switch (iconEntry.wBitCount) { case 2: return QImage::Format_Mono; case 24: return QImage::Format_RGB32; case 32: return QImage::Format_ARGB32; default: return QImage::Format_Indexed8; } break; default: break; } } } return QVariant(); } bool QtIcoHandler::supportsOption(ImageOption option) const { return (option == Size || option == ImageFormat); } /*! * Verifies if some values (magic bytes) are set as expected in the header of the file. * If the magic bytes were found, it is assumed that the QtIcoHandler can read the file. * */ bool QtIcoHandler::canRead() const { if (knownCanRead) return true; bool bCanRead = false; QIODevice *device = QImageIOHandler::device(); if (device) { bCanRead = ICOReader::canRead(device); if (bCanRead) setFormat("ico"); } else { qCWarning(lcIco, "QtIcoHandler::canRead() called with no device"); } knownCanRead = bCanRead; return bCanRead; } /*! This static function is used by the plugin code, and is provided for convenience only. \a device must be an opened device with pointing to the start of the header data of the ICO file. */ bool QtIcoHandler::canRead(QIODevice *device) { Q_ASSERT(device); return ICOReader::canRead(device); } /*! \reimp */ bool QtIcoHandler::read(QImage *image) { bool bSuccess = false; QImage img = m_pICOReader->iconAt(m_currentIconIndex); // Make sure we only write to \a image when we succeed. if (!img.isNull()) { bSuccess = true; *image = img; } return bSuccess; } /*! \reimp */ bool QtIcoHandler::write(const QImage &image) { QIODevice *device = QImageIOHandler::device(); QList imgs; imgs.append(image); return ICOReader::write(device, imgs); } /*! \reimp */ int QtIcoHandler::imageCount() const { return m_pICOReader->count(); } /*! \reimp */ bool QtIcoHandler::jumpToImage(int imageNumber) { if (imageNumber < imageCount()) { m_currentIconIndex = imageNumber; return true; } return false; } /*! \reimp */ bool QtIcoHandler::jumpToNextImage() { return jumpToImage(m_currentIconIndex + 1); } QT_END_NAMESPACE