HEIF Exif support

sylikc · Jun 21, 2023 · 6fab641 · 6fab641
1 parent 0b2a7f0
commit 6fab641
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Showing 3 changed files with 19 additions and 2 deletions.
diff --git a/src/JPEGView/HEIFWrapper.cpp b/src/JPEGView/HEIFWrapper.cpp
@@ -8,6 +8,7 @@ void * HeifReader::ReadImage(int &width,
 					   int &height,
 					   int &nchannels,
 					   int &frame_count,
+					   void* &exif_chunk,
 					   bool &outOfMemory,
 					   int frame_index,
 					   const void *buffer,
@@ -18,6 +19,7 @@ void * HeifReader::ReadImage(int &width,
 	nchannels = 4;
 
 	unsigned char* pPixelData = NULL;
+	exif_chunk = NULL;
 
 	heif::Context context;
 	context.read_from_memory_without_copy(buffer, sizebytes);
@@ -69,5 +71,17 @@ void * HeifReader::ReadImage(int &width,
 	}
 	ICCProfileTransform::DeleteTransform(transform);
 
+	std::vector<heif_item_id> exif_blocks = handle.get_list_of_metadata_block_IDs("Exif");
+
+	if (!exif_blocks.empty()) {
+		std::vector<uint8_t> exif = handle.get_metadata(exif_blocks[0]);
+		exif_chunk = exif.size() > 8 ? (uint8_t*)malloc(exif.size()) : NULL;
+		if (exif_chunk != NULL) {
+			memcpy(exif_chunk, exif.data(), exif.size());
+			*((unsigned short*)exif_chunk) = _byteswap_ushort(0xFFE1);
+			*((unsigned short*)exif_chunk + 1) = _byteswap_ushort(exif.size() - 2);
+		}
+	}
+
 	return (void*)pPixelData;
 }
diff --git a/src/JPEGView/HEIFWrapper.h b/src/JPEGView/HEIFWrapper.h
@@ -10,6 +10,7 @@ class HeifReader
 						 int &height,  // height of the image loaded.
 						 int &bpp,     // BYTES (not bits) PER PIXEL.
 						 int &frame_count, // number of top-level images
+					     void* &exif_chunk, // Pointer to Exif data (must be freed by caller)
 						 bool &outOfMemory, // set to true when no memory to read image
 						 int frame_index, // index of requested frame
 						 const void *buffer, // memory address containing heic compressed data.

diff --git a/src/JPEGView/ImageLoadThread.cpp b/src/JPEGView/ImageLoadThread.cpp
@@ -922,14 +922,16 @@ void CImageLoadThread::ProcessReadHEIFRequest(CRequest* request) {
 			int nWidth, nHeight, nBPP, nFrameCount, nFrameTimeMs;
 			nFrameCount = 1;
 			nFrameTimeMs = 0;
-			uint8* pPixelData = (uint8*)HeifReader::ReadImage(nWidth, nHeight, nBPP, nFrameCount, request->OutOfMemory, request->FrameIndex, pBuffer, nFileSize);
+			void* pEXIFData;
+			uint8* pPixelData = (uint8*)HeifReader::ReadImage(nWidth, nHeight, nBPP, nFrameCount, pEXIFData, request->OutOfMemory, request->FrameIndex, pBuffer, nFileSize);
 			if (pPixelData != NULL) {
 				// Multiply alpha value into each AABBGGRR pixel
 				uint32* pImage32 = (uint32*)pPixelData;
 				for (int i = 0; i < nWidth * nHeight; i++)
 					*pImage32++ = WebpAlphaBlendBackground(*pImage32, CSettingsProvider::This().ColorTransparency());
 
-				request->Image = new CJPEGImage(nWidth, nHeight, pPixelData, NULL, nBPP, 0, IF_HEIF, false, request->FrameIndex, nFrameCount, nFrameTimeMs);
+				request->Image = new CJPEGImage(nWidth, nHeight, pPixelData, pEXIFData, nBPP, 0, IF_HEIF, false, request->FrameIndex, nFrameCount, nFrameTimeMs);
+				free(pEXIFData);
 			}
 		}
 	} catch(heif::Error he) {