qiurui
/
qtimageformats
mirror of https://github.com/qt/qtimageformats.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix tiff reading for 16bpc grayscale with alpha sample 

Having bitPerSample=16 and samplesPerPixel=2, this format was wrongly
identified as a 48bpp rgb image.

Fixes: QTBUG-134112
Pick-to: 6.8
Change-Id: Ib62715f10fa5af899cc130c8951ec346939420b9
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
(cherry picked from commit c4f7a15b0d)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
This commit is contained in:
Eirik Aavitsland 2025-02-26 23:20:31 +01:00 committed by Qt Cherry-pick Bot
parent 28032710d7
commit e36f88b123
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
src/plugins/imageformats/tiff/qtiffhandler.cpp
View File

@ -343,14 +343,15 @@ bool QTiffHandlerPrivate::readHeaders(QIODevice *device)
format = QImage::Format_Grayscale16;
else if ((grayscale || photometric == PHOTOMETRIC_PALETTE) && bitPerSample == 8 && samplesPerPixel == 1)
format = QImage::Format_Indexed8;
else if (samplesPerPixel < 4)
if (bitPerSample == 16 && (photometric == PHOTOMETRIC_RGB || photometric == PHOTOMETRIC_MINISBLACK))
else if (samplesPerPixel < 4) {
bool regular = (samplesPerPixel != 2) && (photometric == PHOTOMETRIC_RGB || photometric == PHOTOMETRIC_MINISBLACK);
if (bitPerSample == 16 && regular)
format = floatingPoint ? QImage::Format_RGBX16FPx4 : QImage::Format_RGBX64;
else if (bitPerSample == 32 && floatingPoint && (photometric == PHOTOMETRIC_RGB || photometric == PHOTOMETRIC_MINISBLACK))
else if (bitPerSample == 32 && floatingPoint && regular)
format = QImage::Format_RGBX32FPx4;
else
format = QImage::Format_RGB32;
else {
} else {
uint16_t count;
uint16_t *extrasamples;
// If there is any definition of the alpha-channel, libtiff will return premultiplied