From ce27d47342d5e076688ead591b279c9b474f99e4 Mon Sep 17 00:00:00 2001
From: Thibault Deckers <thibault.deckers@gmail.com>
Date: Tue, 16 Apr 2024 22:09:57 +0200
Subject: [PATCH] #976 identify Apple variant of HDR images

---
 CHANGELOG.md                                  |  4 +++
 .../channel/calls/MetadataFetchHandler.kt     | 29 +++++++++++++++++++
 .../deckers/thibault/aves/metadata/xmp/XMP.kt |  5 ++++
 3 files changed, 38 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3bda00713..01ef0cb47 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 
 ## <a id="unreleased"></a>[Unreleased]
 
+### Added
+
+- Cataloguing: identify Apple variant of HDR images
+
 ## <a id="v1.10.9"></a>[v1.10.9] - 2024-04-14
 
 ### Fixed
diff --git a/android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataFetchHandler.kt b/android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataFetchHandler.kt
index 0ef28ec13..57a035142 100644
--- a/android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataFetchHandler.kt
+++ b/android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataFetchHandler.kt
@@ -20,6 +20,7 @@ import com.drew.metadata.exif.ExifDirectoryBase
 import com.drew.metadata.exif.ExifIFD0Directory
 import com.drew.metadata.exif.ExifSubIFDDirectory
 import com.drew.metadata.exif.GpsDirectory
+import com.drew.metadata.exif.makernotes.AppleMakernoteDirectory
 import com.drew.metadata.file.FileTypeDirectory
 import com.drew.metadata.gif.GifAnimationDirectory
 import com.drew.metadata.iptc.IptcDirectory
@@ -69,6 +70,7 @@ import deckers.thibault.aves.metadata.metadataextractor.Helper.getSafeRational
 import deckers.thibault.aves.metadata.metadataextractor.Helper.getSafeString
 import deckers.thibault.aves.metadata.metadataextractor.Helper.isPngTextDir
 import deckers.thibault.aves.metadata.metadataextractor.PngActlDirectory
+import deckers.thibault.aves.metadata.metadataextractor.mpf.MpEntry
 import deckers.thibault.aves.metadata.metadataextractor.mpf.MpEntryDirectory
 import deckers.thibault.aves.metadata.xmp.GoogleXMP
 import deckers.thibault.aves.metadata.xmp.XMP
@@ -639,6 +641,10 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
                     // JPEG Multi-Picture Format
                     if (metadata.getDirectoriesOfType(MpEntryDirectory::class.java).count { !it.entry.isThumbnail } > 1) {
                         flags = flags or MASK_IS_MULTIPAGE
+
+                        if (hasAppleHdrGainMap(uri, sizeBytes, metadata)) {
+                            flags = flags or MASK_IS_HDR
+                        }
                     }
 
                     // XMP
@@ -765,6 +771,29 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
         metadataMap[KEY_FLAGS] = flags
     }
 
+    private fun hasAppleHdrGainMap(uri: Uri, sizeBytes: Long?, primaryMetadata: com.drew.metadata.Metadata): Boolean {
+        if (!primaryMetadata.containsDirectoryOfType(AppleMakernoteDirectory::class.java)) return false
+
+        val mpEntries = MultiPage.getJpegMpfEntries(context, uri, sizeBytes) ?: return false
+        mpEntries.filter { it.type == MpEntry.TYPE_UNDEFINED }.forEach { mpEntry ->
+            var dataOffset = mpEntry.dataOffset
+            if (dataOffset > 0) {
+                val baseOffset = MultiPage.getJpegMpfBaseOffset(context, uri, sizeBytes)
+                if (baseOffset != null) {
+                    dataOffset += baseOffset
+                }
+            }
+            StorageUtils.openInputStream(context, uri)?.let { input ->
+                input.skip(dataOffset)
+                val pageMetadata = Helper.safeRead(input)
+                if (pageMetadata.getDirectoriesOfType(XmpDirectory::class.java).any { it.xmpMeta.hasHdrGainMap() }) {
+                    return true
+                }
+            }
+        }
+        return false
+    }
+
     private fun getMultimediaCatalogMetadataByMediaMetadataRetriever(
         mimeType: String,
         uri: Uri,
diff --git a/android/app/src/main/kotlin/deckers/thibault/aves/metadata/xmp/XMP.kt b/android/app/src/main/kotlin/deckers/thibault/aves/metadata/xmp/XMP.kt
index 47a26ca7d..b7d49f9f9 100644
--- a/android/app/src/main/kotlin/deckers/thibault/aves/metadata/xmp/XMP.kt
+++ b/android/app/src/main/kotlin/deckers/thibault/aves/metadata/xmp/XMP.kt
@@ -40,6 +40,7 @@ object XMP {
     private const val XMP_NS_URI = "http://ns.adobe.com/xap/1.0/"
 
     // other namespaces
+    private const val APPLE_HDRGM_NS_URI = "http://ns.apple.com/HDRGainMap/1.0/"
     private const val HDRGM_NS_URI = "http://ns.adobe.com/hdr-gain-map/1.0/"
     private const val PMTM_NS_URI = "http://www.hdrsoft.com/photomatix_settings01"
 
@@ -59,6 +60,7 @@ object XMP {
     // HDR gain map
 
     private val HDRGM_VERSION_PROP_NAME = XMPPropName(HDRGM_NS_URI, "Version")
+    private val APPLE_HDRGM_VERSION_PROP_NAME = XMPPropName(APPLE_HDRGM_NS_URI, "HDRGainMapVersion")
 
     // panorama
 
@@ -137,6 +139,9 @@ object XMP {
             // `Ultra HDR`
             if (GoogleXMP.isUltraHdPhoto(this)) return true
 
+            // Apple HDR gain map
+            if (doesPropExist(APPLE_HDRGM_VERSION_PROP_NAME)) return true
+
             return false
         } catch (e: XMPException) {
             if (e.errorCode != XMPError.BADSCHEMA) {