ImageEn

# FAQ

#### After updating ImageEn I get the following error on Delphi start-up: "The procedure entry point ... could not be located in the dynamic link library DPKIECtrl26.bpl"

There are two common causes for this error:

1. You have multiple copies of the ImageEn BPL files on your system (generally error is for DPKIECtrl*.bpl)

Search your system for any PKIE*.* and DPKIE*.* files and remove them (it might help to review the library paths under Tools > Options, Library). Then reinstall ImageEn.

2. You have another package that uses the ImageEn BPL (generally error is for PKIECtrl*.bpl)

A package - either one of ImageEn's or one of your own - is trying to access PKIECtrl26.bpl, but is failing because PKIECtrl26.bpl has been recompiled more recently. The error may be followed by another one that advised you which package is giving you the error: "Xyz package could not be loaded. Would you like to load it next time you run Delphi...".

If you know which package has caused the problem, open it's DPK file and recompile it. Otherwise, go through each of your packages and recompile any that use ImageEn.

#### How can I prevent the scrollwheel from causing the image to zoom? I want it to remain the original size at all times.

You can use MouseWheelParams:

ImageEnView1.MouseWheelParams.Action := iemwNone;

Other values are iemwVScroll and iemwZoom (default).

#### How do I convert a multi-page GIF image to TIFF format without a visual component?

There are several ways. The simplest is to use TIEMultiBitmap:

var
mbmp: TIEMultiBitmap;
Begin
mbmp := TIEMultiBitmap.Create;
mbmp.Write('D:\out.tiff');
mbmp.free;
End;

#### Can I load PDF files with ImageEn?

- ImageEn PDFium Plug-in
- WPViewPDF commercial plug-in
- ImageMagick + GhostScript

#### How do I disable all keyboard shortcuts in ImageEn?

You need to set the following properties (which are all enabled by default):
- Disable TImageEnView.KeyboardShortcuts
- Remove loKeyboardShortcuts from TImageEnView.LayerOptions
- Remove ieboEnableFileShortcuts from TImageEnFolderMView.FolderInteract
- Disable TIERichEdit.KeyboardShortcuts
- Disable TImageEnViewToolbar/TIERichEditToolbar.KeyboardShortcuts
- Remove Shortcuts from any ImageEn Actions

Configure or disable individual keyboard shortcuts using KeyboardShortcuts

#### Can I modify the scanner resolution?

To change the scan resolution to 300 on your scanner set the following AcquireParams properties:

ImageEnView1.IO.AcquireParams.YResolution := 300;
ImageEnView1.IO.AcquireParams.XResolution := 300;
ImageEnView1.IO.Acquire();

#### Is there any way to save a CMYK TIFF using ImageEn?

To save TIFF with CMYK set TIFF_PhotometInterpret:

ImageEnView1.IO.Params.TIFF_PhotometInterpret := ioTIFF_CMYK;
ImageEnView1.IO.SaveToFile('d:\image.tiff');

#### How can I improve the performance of TImageEnMView when I have many thumbnails?

Ensure you have optimized your settings to ensure the best performance:
• Most importantly, decide whether to load and store full size images, or just preview thumbnails. If you are loading the content of a multi-page file, such as TIFF, for editing and display, then generally you will want StoreType=ietNormal. However, if you are displaying thousands of photos from a folder, for example, then you are better to use load only thumbnails (StoreType is ietThumb or ietFastThumb)
• Load images only on demand (i.e. as they are displayed or needed). To do this, ensure the LoadOnDemand parameter is set for AppendImage, InsertImage, FillFromDirectory or FillFromList. Or if you are just loading a single file with many pages, use LoadFromFileOnDemand
• Lock updating while performing batch operations (LockUpdate/UnlockUpdate)
• Consider options to load EXIF thumbnails or Windows Explorer thumbnails
• Choose a good balance between quality and speed when setting the ThumbnailResampleFilter
• Increasing the size of the image cache can help with general performance, especially when StoreType=ietFastThumb

Also see the Performance demo: \Demos\Multi\MViewPerformance\Performance.dpr

#### Is it possible to de/activate duplex on a scanner?

Set DuplexEnabled to true (or False to disable):

ImageEnView1.IO.AcquireParams.DuplexEnabled := True;

#### I've added the ImageMagick DLL to my application folder, but ImageEn does not support its formats. What do I need to do?

You can automatically register the plug-in DLLs using:

IEGlobalSettings().RegisterPlugIns();

Or manually using:

Note: If ImageMagick has been installed on the system, ImageEn will automatically supports its formats.

#### Can your component take a series of single page TIFF files and create a Multi-Page file from them?

Then set TIFF_ImageIndex and save the page:

ImageEnView1.IO.Params.TIFF_ImageIndex := 0; // increment this value for each page
ImageEnView1.IO.InsertToFileTIFF('D:\multipage.tif');

Otherwise you can use a TImageEnMView component or a TIEMultiBitmap. See the "multi" demo for more detail.

#### How do I change the current page of a TIFF image in TImageEnView?

There are two ways to load several pages from a TIFF:

1) Load a page at the time, using TImageEnView and TIFF_ImageIndex, e.g.

ImageEnView1.IO.Params.TIFF_ImageIndex := page_number; // where page_number is the page to load and starts from 0 (first page)

To determine many pages there are:

page_count := EnumTIFFIm('mytiff.tiff');

2) load all pages using a TImageEnMView:

#### How can I validate that the fonts used when loading a layer file are available on the system?

After loading an ImageEn layer file you can iterate through all of the fonts to ensure they are valid, for example:

// Validate fonts are installed on this system
for i := 0 to ImageEnView1.LayersCount do
begin
if ImageEnView1.Layers[i].Kind = ielkText then
fontName := TIETextLayer( ImageEnView1.Layers[i] ).Font
else
if ImageEnView1.Layers[i].Kind = ielkLine then
fontName := TIELineLayer( ImageEnView1.Layers[i] ).LabelFont
else
continue;

if Screen.Fonts.IndexOf( fontName ) = -1 then
begin
// This font is not installed. Substitute or install it...
end;
end;

#### Is it possible to convert a multipage-image to a different encoding, such as G3 and G4?

Using DuplicateCompressionInfo you must change the compression property for all pages:

// change compression for the first page
ImageEnMView1.MIO.Params[0].TIFF_Compression := ioTIFF_G4FAX;

// change compression for the other pages
ImageEnMView1.MIO.DuplicateCompressionInfo();

// now save
ImageEnMView1.Mio.SaveToFile('output.tif');

#### How can I improve performance when working with many layers?

The main performance properties are:
- LayersCaching: Caches the view of each layer. Much faster but uses more memory.
- LayersFastDrawing: Display quality of layers (and whether the quality view is delayed).
- ZoomFilter/DelayZoomFilter: Display quality of images (and whether the quality view is delayed). This option is ignored if LayersFastDrawing is active
- LayersRotationUseFilterOnPreview: Whether the quality filter (LayersRotationFilter) is previewed without applying the rotation using LayersFixRotations

Here is some example code from the Layers_AllTypes demo:

procedure Tfmain.cmbPreviewQualityChange(Sender: TObject);
const
_cmbPreviewQuality_Fast = 0;
_cmbPreviewQuality_Delayed_Best = 1;
_cmbPreviewQuality_Best = 2;
begin
// Separate code to make it easier to understand

if cmbPreviewQuality.ItemIndex = _cmbPreviewQuality_Fast then
begin
// FASTEST DISPLAY

// Zoom filter
ImageEnView1.ZoomFilter := rfNone;
ImageEnView1.DelayZoomFilter := False;

// Rotation anti-alias
ImageEnView1.LayersRotationFilter := ierBicubic;
ImageEnView1.LayersRotationUseFilterOnPreview := False;

// Fast drawing
ImageEnView1.LayersFastDrawing := iefFast;
end
else
if cmbPreviewQuality.ItemIndex = _cmbPreviewQuality_Delayed_Best then
begin
// DELAYED HIGH QUALITY

// Zoom filter
ImageEnView1.ZoomFilter := rfLanczos3;
ImageEnView1.DelayZoomFilter := True;

// Rotation anti-alias
ImageEnView1.LayersRotationFilter := ierBicubic;
ImageEnView1.LayersRotationUseFilterOnPreview := True;

// Fast drawing
ImageEnView1.LayersFastDrawing := iefDelayed;
end
else
begin
// HIGH QUALITY

// Zoom filter
ImageEnView1.ZoomFilter := rfLanczos3;
ImageEnView1.DelayZoomFilter := False;

// Rotation anti-alias
ImageEnView1.LayersRotationFilter := ierBicubic;
ImageEnView1.LayersRotationUseFilterOnPreview := True;

// Fast drawing
ImageEnView1.LayersFastDrawing := iefNormal;
end;

ImageEnView1.Update();
end;

procedure Tfmain.chkLayerCachingClick(Sender: TObject);
begin
if chkLayerCaching.Checked then
ImageEnView1.LayersCaching := -1
else
ImageEnView1.LayersCaching := 0;
end;

#### Using TImageEnMView, how do I load images as they are displayed?

There are several ways to display images "on demand":

1) If you have a folder containing your images, use FillFromDirectory:

ImageEnMView1.FillFromDirectory('c:\myimages');

2) When you add a new image just set its ImageFileName[], and ImageEn will automatically load the specified file when needed. For example:

idx := ImageEnMView1.AppendImage;
ImageEnMView1.ImageFileName[idx] := 'first.jpg';

3) When you add a new image just set the ImageID[] property. You must create an array of filenames where images are to be loaded. For example:

var
files: array [0..1] of string;
begin
files[0] := 'first.jpg';
files[1] := 'second.jpg';
ImageEnMView1.ImageID[ ImageEnMView1.AppendImage ] := 0;
ImageEnMView1.ImageID[ ImageEnMView1.AppendImage ] := 1;
end;

You must also implement the OnImageIDRequest event, e.g.:

procedure TForm1.OnImageIDRequest(Sender: TObject; ID: integer; var Bitmap: TBitmap);
var
io: TImageEnIO;
begin
io := TImageEnIO.Create(self);
io.AttachedBitmap := bmp; // bmp is a TBitmap object, defined at class level (must exists after the OnImageIDRequest exits)
io.free;
Bitmap := bmp;
end;

4) If the images are frames of a media file (like AVI, MPEG, etc..) you can use LoadFromFileOnDemand:

#### How do I burn the layers (Lines, Ellipses, etc) added in TImageEnView into the image? (Save them as a JPEG file)

Lines, ellipses and other layers added to a TImageEnView can be merged to the background using the LayersMergeAll method, then save the image.

#### How do I modify the IPTC fields without loading the actual image?

The IPTC info is automatically loaded when you load the JPEG image using the LoadFromFile method. After this all IPTC information is loaded into the TImageEnView.IO.Params.IPTC_Info object. To read the caption you can write:

Idx := ImageEnView.IO. Params.IPTC_Info.IndexOf(2, 120);
Caption := ImageEnView.IO.Params.IPTC_Info.StringItem[idx];

To modify the caption:

ImageEnView.IO.Params.IPTC_Info.StringItem[idx] := 'new caption';
ImageEnView.IO.SaveToFile('image2.jpg');

To modify IPTC info without loading the image use ParamsFromFile and InjectJpegIPTC methods, as follows:

ImageEnView.IO.ParamsFromFile('D:\Image.jpg');

...After modifying the IPTC info, save it

ImageEnView.IO.InjectJpegIPTC('D:\Image_ChangedMeta.jpg');

#### How I can save my JPEG without EXIF or other metadata?

Call ResetInfo. For example:

ImageEnView.IO.Params.ResetInfo();
ImageEnView.IO.SaveToFile('output.jpg');

#### How can I check if the TImageEnView is empty (i.e. no bitmap is loaded)?

To empty the component use the "Blank" method. To check if it is empty use IsEmpty:

If ImageEnView1.IsEmpty then
...

#### When a user selects a page of a multipage tiff image displayed in a TImageEnMView, I want the image to be displayed in a TImageEnView.

1. To handle the display automatically specify your TImageEnView for AttachedImageEnView

ImageEnMView1.AttachedImageEnView := ImageEnView1;

2. To manually handle the image selection use the OnImageSelect event. To get the currently selected image simply use the Assign method:

procedure TForm1.ImageEnMView1ImageSelect(Sender: TObject; idx: Integer);
begin
ImageEnView1.Assign( ImageEnMView1.IEBitmap );
end;

#### How do I assign the image in one ImageEnView to another ImageEnView?

Just use Assign method:

ImageEnView1.Assign( ImageEnView2 );

or

ImageEnView1.Assign( ImageEnView1.IEBitmap ); // this doesn't copy DPI or other metadata, just the image

#### What is the correct way to load a Resource Image at runtime into an TImageEnView component in C++?

Here is an example:

TResourceStream *ResourceImage;
ResourceImage = new TResourceStream((int)HInstance, "ABOUTBITMAP", RT_RCDATA);
delete ResourceImage;

Create a text file named "resource.rc" with the single line:
Then add the Resource file to the project and compile.

#### How do I read custom TIFF tags?

This example shows how to read EXIF tags saved by Canon cameras:

var
ms: TMemoryStream;
i: integer;
// some Canon tags
m_nMacroMode, m_nLenghtTimer, m_Quality: integer;
m_ImageType: string;
begin
with ImageEnView1.IO.Params.JPEG_MarkerList do
begin
i := IndexOf( JPEG_APP1 );
if i >= 0 then
begin
// there is EXIF info
ms := TMemoryStream.Create;
ms.Write( MarkerData[i][6], MarkerLength[i] ); // bypass first 4 bytes (must contain 'Exif')
ms.Position := 0;

tagReader3 := TIETifTagsReader.CreateFromIFD( tagReader2, $927c ); // read IFD in tag$927C (MarkerData - Canon IFD data)

ms.Free;
end;
end;
end;

#### How do I compress my JPEGs to make them smaller?

Jpeg is a file format with variable compression rate. The property that regulates the compression (and the quality) is JPEG_Quality. So you should set this property before saving. For example:

ImageEnView.IO.Params.JPEG_Quality := 70;
ImageEnView.IO.SaveToFile('output.jpg');

The default is 80, which provides a good balance between quality and file size.

To estimate the value used to create your file, use:
Quality := IECalcJpegFileQuality('input.jpg');

So you could write:

ImageEnView.IO.Params.JPEG_Quality := IECalcJpegFileQuality('input.jpg');
ImageEnView.IO.SaveToFile('output.jpg');

If the file is still too large it may contain metatags (text info). To remove them, call ResetInfo before saving:

ImageEnView.IO.Params.ResetInfo();

#### How do I load embedded JPEG images in a Raw file?

Use the RAW_GetEmbeddedJpeg property:

ImageEnView.IO.Params.RAW_GetEmbeddedJpeg := True;
ImageEnView.IO.Params.RAW_HalfSize := True;

#### How do I always create a polygon when inserting a polyline layer?

Just set LayersAutoClosePolylines:

// Always close polylines
ImageEnView1.LayersAutoClosePolylines := iecmAlways;

#### How do I read Camera RAW formats?

To read Camera RAW files you must add ielib.dll to your EXE folder, or set IEGlobalSettings().CameraRawEngine to ieenWIC.

#### Why do I get "Floating point overflow" when printing?

This can happen on shared printers due to a bug in the VCL or printer drivers. Try disabling FPU exceptions by executing this before your printing code:

Set8087CW(\$133F);