From d033dbc810a0405bb00b07b18d470833a5de384c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fl=C3=B6ssie?= <floessie.mail@gmail.com>
Date: Tue, 16 Jun 2020 10:52:56 +0200
Subject: [PATCH] Add 300dpi resolution to exported TIFFs (fixes #5787)

---
 rtengine/imageio.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/rtengine/imageio.cc b/rtengine/imageio.cc
index fce181c3f..aa18f1265 100644
--- a/rtengine/imageio.cc
+++ b/rtengine/imageio.cc
@@ -1483,6 +1483,19 @@ int ImageIO::saveTIFF (const Glib::ustring &fname, int bps, bool isFloat, bool u
     TIFFSetField (out, TIFFTAG_COMPRESSION, uncompressed ? COMPRESSION_NONE : COMPRESSION_ADOBE_DEFLATE);
     TIFFSetField (out, TIFFTAG_SAMPLEFORMAT, (bps == 16 || bps == 32) && isFloat ? SAMPLEFORMAT_IEEEFP : SAMPLEFORMAT_UINT);
 
+    [out]()
+    {
+        const std::vector<rtexif::Tag*> default_tags = rtexif::ExifManager::getDefaultTIFFTags(nullptr);
+
+        TIFFSetField (out, TIFFTAG_XRESOLUTION, default_tags[2]->toDouble());
+        TIFFSetField (out, TIFFTAG_YRESOLUTION, default_tags[3]->toDouble());
+        TIFFSetField (out, TIFFTAG_RESOLUTIONUNIT, default_tags[4]->toInt());
+
+        for (auto default_tag : default_tags) {
+            delete default_tag;
+        }
+    }();
+
     if (!uncompressed) {
         TIFFSetField (out, TIFFTAG_PREDICTOR, (bps == 16 || bps == 32) && isFloat ? PREDICTOR_FLOATINGPOINT : PREDICTOR_HORIZONTAL);
     }