fpexif: Provide option to read exif without maker notes (not standardized and poorly documented feature).

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@6091 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/fpexif/examples/metadata_viewer/mdvmain.lfm

@@ -115,18 +115,18 @@ object MainForm: TMainForm
       Height = 573
       Top = 23
       Width = 647
-      ActivePage = PgImage
+      ActivePage = PgMetadata
       Align = alClient
-      TabIndex = 1
+      TabIndex = 0
       TabOrder = 1
       OnChange = PageControl1Change
       object PgMetadata: TTabSheet
         Caption = 'Meta data'
-        ClientHeight = 640
+        ClientHeight = 545
         ClientWidth = 639
         object TagListView: TListView
           Left = 0
-          Height = 640
+          Height = 525
           Top = 0
           Width = 639
           Align = alClient
@@ -155,6 +155,31 @@ object MainForm: TMainForm
           OnCompare = TagListViewCompare
           OnSelectItem = TagListViewSelectItem
         end
+        object Panel1: TPanel
+          Left = 0
+          Height = 20
+          Top = 525
+          Width = 639
+          Align = alBottom
+          AutoSize = True
+          BevelOuter = bvNone
+          ClientHeight = 20
+          ClientWidth = 639
+          TabOrder = 1
+          object CbDecodeMakerNotes: TCheckBox
+            AnchorSideLeft.Control = Panel1
+            AnchorSideTop.Control = Panel1
+            AnchorSideTop.Side = asrCenter
+            Left = 0
+            Height = 19
+            Top = 1
+            Width = 127
+            Caption = 'Decode MakerNotes'
+            Checked = True
+            State = cbChecked
+            TabOrder = 0
+          end
+        end
       end
       object PgImage: TTabSheet
         Caption = 'Image'
@@ -162,7 +187,7 @@ object MainForm: TMainForm
         ClientWidth = 639
         object Image: TImage
           Left = 0
-          Height = 517
+          Height = 545
           Top = 0
           Width = 639
           Align = alClient
@@ -171,40 +196,16 @@ object MainForm: TMainForm
           Stretch = True
           StretchOutEnabled = False
         end
-        object Panel1: TPanel
-          Left = 0
-          Height = 28
-          Top = 517
-          Width = 639
-          Align = alBottom
-          AutoSize = True
-          BevelOuter = bvNone
-          ClientHeight = 28
-          ClientWidth = 639
-          TabOrder = 0
-          Visible = False
-          object CheckBox1: TCheckBox
-            AnchorSideLeft.Control = Panel1
-            AnchorSideTop.Control = Panel1
-            AnchorSideTop.Side = asrCenter
-            Left = 0
-            Height = 19
-            Top = 5
-            Width = 127
-            BorderSpacing.Top = 4
-            BorderSpacing.Bottom = 4
-            Caption = 'Decode MakerNotes'
-            TabOrder = 0
-          end
-        end
       end
     end
     object Messages: TMemo
-      Left = 0
+      Left = 4
       Height = 90
       Top = 596
-      Width = 647
+      Width = 639
       Align = alBottom
+      BorderSpacing.Left = 4
+      BorderSpacing.Right = 4
       TabOrder = 2
     end
     object Splitter3: TSplitter

components/fpexif/examples/metadata_viewer/mdvmain.pas

@@ -14,7 +14,7 @@ type
   { TMainForm }
 
   TMainForm = class(TForm)
-    CheckBox1: TCheckBox;
+    CbDecodeMakerNotes: TCheckBox;
     FilenameInfo: TLabel;
     Image: TImage;
     Messages: TMemo;
@@ -114,6 +114,10 @@ begin
     FImgInfo := TImgInfo.Create;
     try
       try
+        if CbDecodeMakerNotes.Checked then
+          FImgInfo.MetadataKinds := FImgInfo.MetadataKinds + [mdkExif] - [mdkExifNoMakerNotes]
+        else
+          FImgInfo.MetadataKinds := FImgInfo.MetadataKinds - [mdkExif] + [mdkExifNoMakerNotes];
         FImgInfo.LoadFromFile(AFileName);
         Messages.Hide;
       except

components/fpexif/fpeexifreadwrite.pas

@@ -411,6 +411,7 @@ begin
         Move(AData[0], FExifVersion[1], Length(FExifVersion));
       end;
     FULLTAG_MAKERNOTE:
+      if FImgInfo.MetadataKinds * [mdkExif, mdkExifNoMakerNotes] = [mdkExif] then
       begin
         // The stream is at the end of the makernote data area --> rewind it to start
         AStream.Position := AStream.Position - Length(AData);

components/fpexif/fpeglobal.pas

@@ -12,7 +12,12 @@ uses
   Classes, SysUtils;
 
 type
-  TMetaDataKind = (mdkExif, mdkIPTC, mdkComment);
+  TMetaDataKind = (
+    mdkExif,                   // Complete Exif (incl MakerNotes)
+    mdkExifNoMakerNotes,       // Exif without MakerNotes (instead of mdkExif)
+    mdkIPTC,                   // IPTC
+    mdkComment                 // Comment segment
+  );
   TMetaDataKinds = set of TMetaDataKind;
 
 const

components/fpexif/fpemetadata.pas

@@ -459,7 +459,7 @@ begin
     p := AStream.Position;
     case marker of
       M_EXIF:
-        if (mdkEXIF in FMetadataKinds) then begin
+        if FMetaDataKinds * [mdkExif, mdkExifNoMakerNotes] <> [] then begin
           reader := TExifReader.Create(self);
           try
             if not TExifReader(reader).ReadExifHeader(AStream) then
@@ -647,7 +647,7 @@ begin
   AStream.WriteBuffer(SOI_MARKER, SizeOf(SOI_MARKER));
 
   // No Exif --> write an APP0 segment
-  if not HasExif or not (mdkExif in FMetadataKinds) then begin
+  if not HasExif or (FMetadataKinds * [mdkExif, mdkExifNoMakerNotes] = []) then begin
     if Length(FHeaderSegment) = 0 then begin
       Move(JFIF[1], {%H-}JFIFSegment.Identifier[0], Length(JFIF));
       JFIFSegment.JFIFVersion[0] := 1;