diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/3rdparty/zlib_dependency.pri | 5 | ||||
| -rw-r--r-- | src/plugins/imageformats/tiff/qtiffhandler.cpp | 15 |
2 files changed, 17 insertions, 3 deletions
diff --git a/src/3rdparty/zlib_dependency.pri b/src/3rdparty/zlib_dependency.pri index 4194fe2..5cccf37 100644 --- a/src/3rdparty/zlib_dependency.pri +++ b/src/3rdparty/zlib_dependency.pri @@ -1,7 +1,10 @@ # zlib dependency satisfied by bundled 3rd party zlib or system zlib contains(QT_CONFIG, system-zlib) { unix|mingw: LIBS_PRIVATE += -lz - else: LIBS += zdll.lib + else { + isEmpty(ZLIB_LIBS): LIBS += zdll.lib + else: LIBS += $$ZLIB_LIBS + } } else { QT_PRIVATE += zlib-private } diff --git a/src/plugins/imageformats/tiff/qtiffhandler.cpp b/src/plugins/imageformats/tiff/qtiffhandler.cpp index e0c17ce..f72c2a0 100644 --- a/src/plugins/imageformats/tiff/qtiffhandler.cpp +++ b/src/plugins/imageformats/tiff/qtiffhandler.cpp @@ -257,8 +257,19 @@ bool QTiffHandlerPrivate::openForRead(QIODevice *device) format = QImage::Format_Indexed8; else if (samplesPerPixel < 4) format = QImage::Format_RGB32; - else - format = QImage::Format_ARGB32_Premultiplied; + else { + uint16 count; + uint16 *extrasamples; + // If there is any definition of the alpha-channel, libtiff will return premultiplied + // data to us. If there is none, libtiff will not touch it and we assume it to be + // non-premultiplied, matching behavior of tested image editors, and how older Qt + // versions used to save it. + bool gotField = TIFFGetField(tiff, TIFFTAG_EXTRASAMPLES, &count, &extrasamples); + if (!gotField || !count || extrasamples[0] == EXTRASAMPLE_UNSPECIFIED) + format = QImage::Format_ARGB32; + else + format = QImage::Format_ARGB32_Premultiplied; + } headersRead = true; return true; |