From 496807b616744117fe8ce8dbac50261a7e8b6fbe Mon Sep 17 00:00:00 2001
From: Georg Hagen <git.georg.hagen@madvoxel.com>
Date: Thu, 13 Feb 2025 23:28:23 +0100
Subject: [PATCH] Add exif and xmp to full resolution images saved to disk

---
 openVulkanoCpp/AR/ArFrame.hpp    |  2 ++
 openVulkanoCpp/AR/ArRecorder.cpp | 31 +++++++++++++++++++++++++++----
 openVulkanoCpp/AR/ArType.hpp     |  5 ++++-
 3 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/openVulkanoCpp/AR/ArFrame.hpp b/openVulkanoCpp/AR/ArFrame.hpp
index 40f832c..d1dd99d 100644
--- a/openVulkanoCpp/AR/ArFrame.hpp
+++ b/openVulkanoCpp/AR/ArFrame.hpp
@@ -153,6 +153,8 @@ namespace OpenVulkano::AR
 		[[nodiscard]] virtual Math::Matrix4f GetCameraViewForCurrentDeviceOrientation() = 0;
 
 		[[nodiscard]] const Math::Matrix4f& GetCameraProjection() const { return frameMetadata.projection; }
+		
+		[[nodiscard]] const Math::CameraIntrinsicWithResolution& GetCameraIntrinsic() const { return frameMetadata.intrinsic; }
 
 		[[nodiscard]] virtual Math::Matrix4f GetCameraProjection(Math::Vector2f viewportSize, float near = 0.25f, float far = 250.0f) = 0;
 
diff --git a/openVulkanoCpp/AR/ArRecorder.cpp b/openVulkanoCpp/AR/ArRecorder.cpp
index 1503f31..1c23438 100644
--- a/openVulkanoCpp/AR/ArRecorder.cpp
+++ b/openVulkanoCpp/AR/ArRecorder.cpp
@@ -14,6 +14,9 @@
 #include "Base/BlockProfiler.hpp"
 #include "Base/Logger.hpp"
 #include "Image/YuvUtils.hpp"
+#include "Image/ExifBuilder.hpp"
+#include "Image/XmpBuilder.hpp"
+#include "Image/JpegWithTagsWriter.hpp"
 #include <fstream>
 #include <iostream>
 #if __has_include("turbojpeg.h")
@@ -25,10 +28,10 @@ namespace OpenVulkano::AR
 {
 	namespace
 	{
-		constexpr int JPEG_QUALITY_DS = 85;
+		constexpr int JPEG_QUALITY_DS = 90;
 		constexpr int JPEG_QUALITY_FS = 100;
 
-		std::filesystem::path GeneratePath(const std::filesystem::path& baseDir, std::string_view name)
+		std::filesystem::path GeneratePath(const std::filesystem::path& baseDir, const std::string_view name)
 		{
 			std::stringstream ss;
 			auto t = std::time(nullptr);
@@ -108,9 +111,29 @@ namespace OpenVulkano::AR
 				colorWriter->AddFile(fileName.c_str(), outBuffer, size);
 			if (path) [[unlikely]]
 			{
-				std::ofstream outFile(*path, std::ios::binary);
+				/*std::ofstream outFile(*path, std::ios::binary);
 				outFile.write(reinterpret_cast<const char*>(outBuffer), size);
-				outFile.close();
+				outFile.close();*/
+				Image::ExifBuilder exifBuilder;
+				exifBuilder.model = arFrame->GetLensModel();
+				exifBuilder.exposureTime = Image::RationalValue(1, 1.0f / arFrame->GetExposureTime());
+				exifBuilder.SetOrientation(atan2f(arFrame->GetCameraTransformation()[0][1], arFrame->GetCameraTransformation()[1][1]));
+				exifBuilder.dateTaken = exifBuilder.GetCurrentTimestamp();
+				exifBuilder.make = arFrame->GetArSession()->GetArType().GetVendorName();
+				exifBuilder.SetResolution();
+				exifBuilder.fNumber = arFrame->GetFNumber();
+				exifBuilder.focalLength = arFrame->GetFocalLength();
+				auto exif = exifBuilder.Build();
+				Image::XmpBuilder xmpBuilder;
+				xmpBuilder.SetPose(arFrame->GetPose());
+				xmpBuilder.SetCreateDate(exifBuilder.dateTaken); //TODO
+				xmpBuilder.SetExposureTime(arFrame->GetExposureTime());
+				xmpBuilder.SetFocalLength(arFrame->GetFocalLength());
+				xmpBuilder.SetCameraIntrinsic(arFrame->GetCameraIntrinsic());
+				JpegWithTagsWriter writer(*path);
+				writer.WriteExifTag(exif);
+				writer.WriteXmpTag(xmpBuilder.Finalize());
+				writer.WriteImageData({ outBuffer, size });
 			}
 		}
 		tjFree(outBuffer);
diff --git a/openVulkanoCpp/AR/ArType.hpp b/openVulkanoCpp/AR/ArType.hpp
index 4ef1298..dafab85 100644
--- a/openVulkanoCpp/AR/ArType.hpp
+++ b/openVulkanoCpp/AR/ArType.hpp
@@ -12,7 +12,8 @@ namespace OpenVulkano::AR
 {
 	class ArType final
 	{
-		static inline constexpr std::string_view HUMAN_READABLE_NAMES[] = { "Unknown", "ARKit", "ARCore" };
+		static constexpr std::string_view HUMAN_READABLE_NAMES[] = { "Unknown", "ARKit", "ARCore" };
+		static constexpr std::string_view VENDOR_NAME[] = { "Unknown", "Apple", "Google" };
 
 	public:
 		enum Type : uint8_t { UNKNOWN = 0, AR_KIT, AR_CORE };
@@ -38,6 +39,8 @@ namespace OpenVulkano::AR
 			return HUMAN_READABLE_NAMES[m_type];
 		}
 
+		[[nodiscard]] const std::string_view& GetVendorName() const { return VENDOR_NAME[m_type]; }
+
 		static ArType GetFromHumanReadableName(const std::string_view& name)
 		{
 			uint8_t i = 0;