Add support for reading BigTIFF

All recent versions of libtiff has support for the 64bit-indexed
BigTIFF format. Allow reading it by recognizing its magic number.

[ChangeLog][TIFF] Add support for reading BigTIFF

Fixes: QTBUG-80538
Change-Id: I7fcb72d77e4a0bdcb38ab96e9f6cfaff7cf4ad49
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

6 files changed, 33 insertions, 0 deletions

diff --git a/tests/auto/tiff/tst_qtiff.cpp b/tests/auto/tiff/tst_qtiff.cpp
index be02460..e411f66 100644
--- a/tests/auto/tiff/tst_qtiff.cpp
+++ b/tests/auto/tiff/tst_qtiff.cpp
@@ -90,6 +90,9 @@ private slots:
     void colorSpace_data();
     void colorSpace();
 
+    void bigtiff_data();
+    void bigtiff();
+
 private:
     QString prefix;
 };
@@ -173,6 +176,10 @@ void tst_qtiff::readImage_data()
     QTest::newRow("tiled_oddsize_mono") << QString("tiled_oddsize_mono.tiff") << QSize(59, 71);
     QTest::newRow("16bpc") << QString("16bpc.tiff") << QSize(64, 46);
     QTest::newRow("gray16") << QString("gray16.tiff") << QSize(64, 46);
+    QTest::newRow("big_rgb") << QString("big_rgb.tiff") << QSize(64, 64);
+    QTest::newRow("big_rgb_bigendian") << QString("big_rgb_bigendian.tiff") << QSize(64, 64);
+    QTest::newRow("big_grayscale") << QString("big_grayscale.tiff") << QSize(64, 64);
+    QTest::newRow("big_16bpc") << QString("big_16bpc.tiff") << QSize(64, 46);
 }
 
 void tst_qtiff::readImage()
@@ -665,5 +672,27 @@ void tst_qtiff::colorSpace()
     QCOMPARE(image2, image);
 }
 
+void tst_qtiff::bigtiff_data()
+{
+    QTest::addColumn<QString>("expectedFile");
+    QTest::addColumn<QString>("bigtiffFile");
+
+    QTest::newRow("big_rgb") << QString("original_rgb.tiff") << QString("big_rgb.tiff");
+    QTest::newRow("big_rgb_bigendian") << QString("original_rgb.tiff") << QString("big_rgb_bigendian.tiff");
+    QTest::newRow("big_grayscale") << QString("original_grayscale.tiff") << QString("big_grayscale.tiff");
+    QTest::newRow("big_16bpc") << QString("16bpc.tiff") << QString("big_16bpc.tiff");
+}
+
+void tst_qtiff::bigtiff()
+{
+    QFETCH(QString, expectedFile);
+    QFETCH(QString, bigtiffFile);
+
+    QImage expectedImage(prefix + expectedFile);
+    QImage bigtiffImage(prefix + bigtiffFile);
+    QVERIFY(!bigtiffImage.isNull());
+    QCOMPARE(expectedImage, bigtiffImage);
+}
+
 QTEST_MAIN(tst_qtiff)
 #include "tst_qtiff.moc"
diff --git a/tests/shared/images/tiff.qrc b/tests/shared/images/tiff.qrc
index e1ce9da..2c876af 100644
--- a/tests/shared/images/tiff.qrc
+++ b/tests/shared/images/tiff.qrc
@@ -52,5 +52,9 @@
         <file>tiff/oddsize_mono.tiff</file>
         <file>tiff/tiled_rgb.tiff</file>
         <file>tiff/gray16.tiff</file>
+        <file>tiff/big_rgb.tiff</file>
+        <file>tiff/big_16bpc.tiff</file>
+        <file>tiff/big_grayscale.tiff</file>
+        <file>tiff/big_rgb_bigendian.tiff</file>
     </qresource>
 </RCC>
diff --git a/tests/shared/images/tiff/big_16bpc.tiff b/tests/shared/images/tiff/big_16bpc.tiff
new file mode 100644
index 0000000..09f949c
--- /dev/null
+++ b/tests/shared/images/tiff/big_16bpc.tiff
diff --git a/tests/shared/images/tiff/big_grayscale.tiff b/tests/shared/images/tiff/big_grayscale.tiff
new file mode 100644
index 0000000..244f8fc
--- /dev/null
+++ b/tests/shared/images/tiff/big_grayscale.tiff
diff --git a/tests/shared/images/tiff/big_rgb.tiff b/tests/shared/images/tiff/big_rgb.tiff
new file mode 100644
index 0000000..18eecf2
--- /dev/null
+++ b/tests/shared/images/tiff/big_rgb.tiff
diff --git a/tests/shared/images/tiff/big_rgb_bigendian.tiff b/tests/shared/images/tiff/big_rgb_bigendian.tiff
new file mode 100644
index 0000000..0d1a11f
--- /dev/null
+++ b/tests/shared/images/tiff/big_rgb_bigendian.tiff