diff options
| -rw-r--r-- | src/plugins/imageformats/tiff/qtiffhandler.cpp | 16 | ||||
| -rw-r--r-- | tests/auto/tiff/tst_qtiff.cpp | 4 |
2 files changed, 14 insertions, 6 deletions
diff --git a/src/plugins/imageformats/tiff/qtiffhandler.cpp b/src/plugins/imageformats/tiff/qtiffhandler.cpp index 93fd1ed..3fc1680 100644 --- a/src/plugins/imageformats/tiff/qtiffhandler.cpp +++ b/src/plugins/imageformats/tiff/qtiffhandler.cpp @@ -232,7 +232,7 @@ bool QTiffHandlerPrivate::openForRead(QIODevice *device) else if (samplesPerPixel < 4) format = QImage::Format_RGB32; else - format = QImage::Format_ARGB32; + format = QImage::Format_ARGB32_Premultiplied; headersRead = true; return true; @@ -275,7 +275,9 @@ bool QTiffHandler::read(QImage *image) return false; QImage::Format format = d->format; - if (format == QImage::Format_RGB32 && image->format() == QImage::Format_ARGB32) + if (format == QImage::Format_RGB32 && + (image->format() == QImage::Format_ARGB32 || + image->format() == QImage::Format_ARGB32_Premultiplied)) format = image->format(); if (image->size() != d->size || image->format() != format) @@ -647,10 +649,14 @@ bool QTiffHandler::write(const QImage &image) } TIFFClose(tiff); } else { + const bool premultiplied = image.format() != QImage::Format_ARGB32 + && image.format() != QImage::Format_RGBA8888; + const uint16 extrasamples = premultiplied ? EXTRASAMPLE_ASSOCALPHA : EXTRASAMPLE_UNASSALPHA; if (!TIFFSetField(tiff, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_RGB) || !TIFFSetField(tiff, TIFFTAG_COMPRESSION, compression == NoCompression ? COMPRESSION_NONE : COMPRESSION_LZW) || !TIFFSetField(tiff, TIFFTAG_SAMPLESPERPIXEL, 4) - || !TIFFSetField(tiff, TIFFTAG_BITSPERSAMPLE, 8)) { + || !TIFFSetField(tiff, TIFFTAG_BITSPERSAMPLE, 8) + || !TIFFSetField(tiff, TIFFTAG_EXTRASAMPLES, 1, &extrasamples)) { TIFFClose(tiff); return false; } @@ -658,9 +664,11 @@ bool QTiffHandler::write(const QImage &image) const int chunks = (width * height * 4 / (1024 * 1024 * 16)) + 1; const int chunkHeight = qMax(height / chunks, 1); + const QImage::Format format = premultiplied ? QImage::Format_RGBA8888_Premultiplied + : QImage::Format_RGBA8888; int y = 0; while (y < height) { - const QImage chunk = image.copy(0, y, width, qMin(chunkHeight, height - y)).convertToFormat(QImage::Format_RGBA8888); + const QImage chunk = image.copy(0, y, width, qMin(chunkHeight, height - y)).convertToFormat(format); int chunkStart = y; int chunkEnd = y + chunk.height(); diff --git a/tests/auto/tiff/tst_qtiff.cpp b/tests/auto/tiff/tst_qtiff.cpp index 89630c2..71c3b63 100644 --- a/tests/auto/tiff/tst_qtiff.cpp +++ b/tests/auto/tiff/tst_qtiff.cpp @@ -366,7 +366,7 @@ void tst_qtiff::readWriteNonDestructive_data() QTest::addColumn<bool>("grayscale"); QTest::newRow("tiff mono") << QImage::Format_Mono << QImage::Format_Mono << false; QTest::newRow("tiff indexed") << QImage::Format_Indexed8 << QImage::Format_Indexed8 << false; - QTest::newRow("tiff argb32") << QImage::Format_ARGB32 << QImage::Format_ARGB32 << false; + QTest::newRow("tiff argb32pm") << QImage::Format_ARGB32_Premultiplied << QImage::Format_ARGB32_Premultiplied << false; QTest::newRow("tiff rgb32") << QImage::Format_RGB32 << QImage::Format_RGB32 << false; QTest::newRow("tiff grayscale") << QImage::Format_Indexed8 << QImage::Format_Indexed8 << true; } @@ -410,7 +410,7 @@ void tst_qtiff::largeTiff() QSKIP("not tested on WinCE"); #endif - QImage img(4096, 2048, QImage::Format_ARGB32); + QImage img(4096, 2048, QImage::Format_ARGB32_Premultiplied); QPainter p(&img); img.fill(0x0); |