ABCpdf uses the temp directory.

You can override the location it uses by setting this value.

By setting this value to 1, you can ensure full compatibility with ABCpdf version 3 layout algorithms.

By setting this value to 1, you can ensure full compatibility with ABCpdf version 4 layout algorithms.

By setting this value to 1, you can ensure full compatibility with ABCpdf version 5 layout algorithms.

ABCpdf compresses black and white images using CCITT compression.

You can disable this type of compression if you wish to produce simple flate compressed images.

When you insert JPEGs using the Image object, they bypass the normal rendering process and are inserted direct. This can result in a considerable reduction in file size without any loss of visual quality.

However, the final output may vary slightly from that produced by older versions of ABCpdf.

By setting this value to 0, you can ensure compatibility.

HTML rendering sometimes requires two stages: an information gathering stage and a render stage.

For backwards compatibility reasons, you can insert a delay between these two stages. This value is measured in milliseconds.

Certain HTML temp files are automatically deleted by ABCpdf after use.

You are unlikely to want to change the value of this key.

Determines whether errors will be logged in the Application Event Log.

Whether ABCpdf should automatically attempt to recover from serious errors.

This is generally set to false. Recovery may work in some situations but in others it will leave the application in an inconsistent state.

If true, certain run-time consistency checks will be enabled.

If any consistency check fails, then an error will be logged in the Application Event Log.

On startup, the ABCpdf temp directory is checked. If it appears that there are a large number of unused items, then the directory will be cleared.

This setting determines the maximum number of items which are permitted in the directory before a clearout is deemed necessary.

This property is included for backwards compatibility reasons.

Whether registry keys can be overridden on a per-document basis.

To override a registry key, use SetInfo with the name of the key and passing zero as the ID. For example:

theDoc.SetInfo(0, "UseScript", "1")

Note that only keys marked as overridable can be overridden this way.

Some PDFs do not conform to Adobe document structuring conventions. For details see section 4.3.1 of the Adobe PDF Specification.

Conforming documents should save the graphics state at the start of drawing and restore the graphics state after drawing is complete. This way it is guaranteed that drawing operations are independent of each other.

Non-conforming documents may make transform and other graphics state changes which cannot easily be undone. When you add your content, it is affected by these leftover state changes.

This key determines whether ABCpdf will automatically detect and fix non-conforming documents.

The default width of borders on Annotations added to PDF documents.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

The size at which a binary search tree is constructed for HTML rendering.

For larger documents, a binary search tree is a much more efficient structure for HTML rendering than is a linear search tree.

For smaller documents, the time taken to build the tree can outweigh the speed advantages so a linear search tree is better.

This property determines the point at which ABCpdf shifts its strategy from linear to binary searches. The number relates to the number of object fragments in the HTML. The number of object fragments is extremely dependent on the complexity of the page, but a couple of hundred object fragments per PDF page would not be atypical.

Whether to automatically disable HTML filters.

HTML filters can interfere with the HTML to PDF conversion process because they are raster rather than vector based. For this reason, we try to disable them.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

The threshold at which images are JPEG compressed.

When an uncompressed image is added to a document ABCpdf may decide whether to use JPEG (lossy) compression or lossless compression based on an analysis of the image.

ABCpdf counts the number of colors used in the image and if the number is greater than this threshold ABCpdf assumes that the image is continuous tone and thus eligible for JPEG compression. The threshold for grayscale images is half that for color images.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

Whether we allow MSHTML to be unloaded when the screen depth changes.

Appropriate values are 0 (MSHTML is never unloaded) and 10 (it is unloaded a little while after the screen properties change).

The number actually refers to the number of calls that ABCpdf makes (once a monitor change has occurred) without keeping MSHTML force loaded. We assume that at some point during this period, Windows will unload the DLL.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

Whether to make URLs unique when the page cache is disabled. A URL parameter with a 7-random-uppercase-letter name and a 7-random-uppercase-letter value is added to the URL. It is applied to URLs that contain queries or have paths that do not end with a slash.

Sometimes caching can occur outside of ABCpdf. Making the URL unique can provide an effective way of forcing the page to be refreshed.

Whether to preflight objects in the destination document when appending or adding a page from another document.

Dynamically generated PDFs can contain partially constructed objects. At the point that two documents are combined the partially constructed objects need to be finished in order to ensure that the new combination is going to be valid.

For example, you add a subsetted font and some text to a document. As you add more text, a list of characters is built up. At the point that the document is saved, the font object and the character list need to be combined for a sensible font subset to be formed. This font is an example of a partially constructed object.

In general if your source documents are read from existing PDF templates then they will not contain any partially constructed objects. It is only if the dopcuments are corrupt or if you are adding text, that partially constructed objects may be present.

If this property is set to a non-zero value, then ABCpdf will preflight all objects in the destination document. This process requires significant amounts of time if the destination document contains many indirect objects.

Whether to eliminate redundant objects on save or append.

Sometimes PDFs can contain duplicate objects. Eliminating these duplicates can reduce the size of certain PDF documents.

If this property is set to a non-zero value, then ABCpdf will attempt to eliminate any redundant objects. This process requires significant amount of memory and time if the documents contain many indirect objects.

For appending one document to another, any non-zero value other than 2 indicates partial refactoring where some redundant objects that form circular references may not be eliminated, but this takes shorter time. The value 2 indicates full refactoring. For saving to file or memory, any non-zero value indicates full refactoring.

The maximum number of children of non-leaf nodes in the page tree. If it is 2 or below, no balancing of the page tree is performed.

The page tree gives the order to the pages. The look-up of pages from page numbers and the identification of page numbers from the pages' IDs are performed using the page tree. The time complexity of these operations is O(PagesMaxKids×log PageCount/log PagesMaxKids) so the smaller PagesMaxKids, the faster the operations.

If the value is 3 or above, the entire tree is balanced when the first time the page tree is modified either by adding a page or removing a page or a non-leaf node (a Pages object). When a page is added such that the parent node has more than PagesMaxKids children or when a page or a non-leaf node is removed such that the (non-root) parent node has less than PagesMaxKids/2 children (or equivalently, less than the floor of (PagesMaxKids + 1)/2 children), the page tree is partially balanced. The balancing of the tree is triggered more often if PagesMaxKids is small.

(For HTML Import) ABCpdf treats background and foreground images differently. For example, it is generally acceptable to split a background image across pages while it is much less acceptable to split a foreground image in this way.

For this reason, ABCpdf tries to determine whether images are foreground or background using a variety of methods.

If the same image appears a number of times within a limited area of the HTML, ABCpdf will assume it is a background image.

This property represents the vertical distance (in pixels) above a particular image in which ABCpdf looks for repeated images.

(For HTML Import) ABCpdf treats background and foreground images differently. For example, it is generally acceptable to split a background image across pages while it is much less acceptable to split a foreground image in this way.

For this reason, ABCpdf tries to determine whether images are foreground or background using a variety of methods.

If the same image appears a number of times within a limited area of the HTML, ABCpdf will assume it is a background image.

This property represents the number of repeats above which ABCpdf determines that the image is background.

(For HTML Import) ABCpdf treats background and foreground images differently. For example, it is generally acceptable to split a background image across pages while it is much less acceptable to split a foreground image in this way.

For this reason, ABCpdf tries to determine whether images are foreground or background using a variety of methods.

If an image is very tall and thin, ABCpdf will assume it is a background image.

This property represents the maximum width for this test.

(For HTML Import) ABCpdf treats background and foreground images differently. For example, it is generally acceptable to split a background image across pages while it is much less acceptable to split a foreground image in this way.

For this reason, ABCpdf tries to determine whether images are foreground or background using a variety of methods.

If an image is very tall and thin, ABCpdf will assume it is a background image.

This property represents the minimum height for this test.

(For HTML Import) Sometimes, Windows can tell ABCpdf that an HTML page is complete even though background images have not yet finished loading.

This option allows you to specify that ABCpdf should force-load any background images.

(For HTML Import) Change this value to change the extra margin that ABCpdf adds at the bottom when rendering HTML pages. Due to rendering issues in Internet Explorer, it is necessary to make the HTML page a bit taller. This extra margin is then clipped and so it does not alter the final PDF output.

However, if the page contains objects positioned relatively to the bottom of the page, the objects may be clipped/shifted. Set this property to zero or to a smaller value in order to avoid such problems.

The initial value of XHtmlOptions.HostWebBrowser.

When importing EMF or HTML content, this property specifies the minimum EMF-to-PDF character-width ratio in 1000ths.

Characters whose (EMF and PDF) widths form ratios between the specified minimum and CharWidthRatioMax (exclusively) assume the PDF character widths as font substitution may occur. Characters whose widths form ratios outside the interval are placed as specified because the text is placed in an unusual way.

When importing EMF or HTML content, this property specifies the maximum EMF-to-PDF character-width ratio in 1000ths.

Characters whose (EMF and PDF) widths form ratios between CharWidthRatioMin and the specified maximum (exclusively) assume the PDF character widths as font substitution may occur. Characters whose widths form ratios outside the interval are placed as specified because the text is placed in an unusual way.

When HTML contained Flash (SWF) movies are added to a PDF document, ABCpdf will make a preview image for the movie.

The preview is what you will see if you don't have Flash installed. It is what is used when printing PDFs. In general, it is what you will see if you open your PDF using a viewer other than Acrobat.

This value is used for SWF raster import in previous versions of ABCpdf and has the same meaning as FlashPreviewWaitTime for SWF vector import.

When the movie is intialized, you can specify a time (in milliseconds) at which the movie will be started.

Note that many movies contain script which can alter the way that the movie is played. For example, a script might reset the the current frame to the start after five seconds of content have been played. So the content you get by setting the preview time to ten seconds may be very different to the content a user will see after watching the movie for ten seconds.

When HTML contained Flash (SWF) movies are added to a PDF document, ABCpdf will make a preview image for the movie.

The preview is what you will see if you don't have Flash installed. It is what is used when printing PDFs. In general, it is what you will see if you open your PDF using a viewer other than Acrobat.

This property determines the time (in milliseconds) that the movie will be given to play before the preview will be made.

Note that many movies contain script which can alter the way that the movie is played. For example, a movie might reset the the current frame to the start after five seconds of content have been played. So the content you get by setting the preview time to ten seconds may be very different to the content a user will see after watching the movie for ten seconds.

When HTML contained Flash (SWF) movies are added to a PDF document, ABCpdf will make a preview image for the movie.

The preview is what you will see if you don't have Flash installed. It is what is used when printing PDFs. In general, it is what you will see if you open your PDF using a viewer other than Acrobat.

This value is used for SWF raster import in previous versions of ABCpdf and is not used for SWF vector import.

This property determines the resolution (in dots per inch) at which the preview will be made.

This parameter allows low-level control over the way that documents are rendered to vector formats like EMF and EPS.

During the generation of an EMF or EPS file, bitmap generation due to transparency detection will be suppressed. This can cause some unexpected results as neither EMF nor EPS format supports transparency and non-default blending modes to the extent that PDF does.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

This parameter allows low-level control over the way that documents are rendered to bitmap outputs.

During the generation of a high-resolution or scene-antialiased bitmap, the renderer stores PDF rendering objects in a display list. The bitmap is broken into sections and the display list is rendered to each section.

For some very complex PDF files, this display list can become rather large and consume a lot of memory. In these cases, it is better to allocate a complete image and render the PDF objects directly to the image than it is to try and store the individual PDF objects.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

This parameter allows low-level control over the way that text is rendered into vector formats like EPS.

If the value is true, the text is placed directly into the output file when possible. If it is false, the text is converted to vectors, which are then output to the file.

The former method results in smaller files. The latter results in larger but font-independent output files. It is important to note that not everything that looks like text is actually text or can be extracted as text.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

This parameter allows low-level control over the way that documents are rendered to EMF.

This setting controls the type of EMF output. Possible values are:

• 0 - EmfOnly
• 1 - EmfPlusOnly
• 2 - EmfPlusDual.

You may want to change the setting to EmfPlusDual, which means that both EMF and EMF+ entries are included in the output. This produces greater compatibility but at the cost of a doubling in file size.

This property is only accessible using the SetInfo method. The default cannot be overridden using a registry key.

This parameter allows control over the way that text field appearances are generated.

Some documents contain text fields which are not tall enough for the text that they contain. There are two choices here. You can preserve the requested text size and let the text be clipped. Alternatively, you can reduce the text size so that it fits the height of the field.

The default behavior is to reduce the text size. However, in some cases you may want to override this behavior by altering this setting.

Changing the screen resolution while a process is running can cause some versions of MSHTML to become confused. If the screen size is reduced then portions of the output HTML may be clipped at the right hand side.

It is unusual for this to be a problem because changing the screen resolution is not a normal event. However some remote access applications can change screen settings in an uncontrolled way which means that someone logging onto a server remotely can sometimes trigger this kind of event in a long running process such as a web application.

This registry key allows you to control what ABCpdf does when this type of event is detected. The possible options are.

• 0 - Ignore any screen changes.
• 1 - Raise an exception "Display settings changed.". This may be used as a trigger for recycling the current package and thus resolving the issue.
• 2 - Attempt to revert screen to previous settings, raising an exception only if this could not be done.

This registry key allows you to control the installation of embedded fonts when rendering to EMF.

By default, when you use Rendering.GetData to render to EMF, fonts will be installed in memory and will remain available to the ABCpdf process until Doc.Clear is called. This means that the EMF can be spooled to a printer and the fonts will appear correctly.

By default, when you use Rendering.Save to render to EMF, embedded fonts are not installed and text will be rendered as polygons for any fonts that are not available on the system. This is because when an EMF file is viewed outside the ABCpdf process, memory-resident fonts are not available. Thus any text using those fonts would be subject to font substitution by Windows.

Set this value to 0xFFFFFFFF to disable the installation of embedded fonts in memory, even when calling Rendering.GetData. This results in text rendered with polygons for embedded fonts. Hence, the rendering is slower and the output is bigger.

Set this value to 1 to always install fonts, even when calling Rendering.Save. This results in faster rendering and smaller outputs. However, viewing emf files outside the ABCpdf process may not display embedded fonts correctly.

Set this value to 1 to enable the logging of the PrintHook library using %SystemRoot%\Temp or set it to a path to a folder to enable the logging using that folder.

The PrintHook library is used to print files to XPS, which are then converted to PDF in ImportAny operations. We may ask you to enable the logging and send us the log files for debugging purposes if you request us to solve related problems.

Log files are named spy_<PID>.txt.

On 64-bit machines, you will need to set this value in the 32-bit registry section (Wow6432Node) as well for intercepting 32-bit processes.

Set this value to 1 for viewing applications that are launched by Operations.ImportAny(), typically Office applications. Set it to 0 or remove it to hide them.

We use Office applications to print their documents to XPS files, which we then convert to PDF. Sometimes these applications get stuck on pop-ups of various types, so it may be useful to see what they are doing.

Please note that there are limitations with this feature—it may not be possible to view applications that run under a different user account. This is normally the case when running Office Applications in a web server process.

This setting allows you to override the default URL security policies in place on your machine. You can open up or lock down security settings using this registry key.

The string is a sequence of URL Actions (such as URLACTION_HTML_META_REFRESH) and policies (eg URLPOLICY_DISALLOW) in a space delimited list. Appropriate values for these type of actions and policies can be found on the Microsoft web site. The default value for this setting disables meta-refresh tags.

Treat with caution as existing security settings are there for a reason.

Cross domain operations are not normally permitted when accessing the HTML DOM. This means that if you have a frameset on one domain and frames in another ABCpdf will be unable to determine appropriate widths and heights for any of the frames.

Ideally to resolve this type of issue you should move the pages to the same domain or reference the domain within the frameset to ensure that MSHTML will allow this type of cross domain scripting. In situations where this is not possible you can specify sites which should be trusted. Any page URLs which start with one of the trusted site URLs will be assigned a special trusted status.

URL lists are space delimited. For example:

http://www.google.com/ http://www.microsoft.com/ http://www.yahoo.com/

Treat with caution as existing security settings are there for a reason.

Some PDFs contain color profiles which do not handle black objects correctly.

This option allows you to bypass the profile transformation if the input colorspace is CMYK ICC and the output is device CMYK, or if the input is Gray ICC based and the output is device CMYK.

• 0 - ABCpdf will write the required registry configuration to the HKCU registry hive. For IIS applications, this requires "Load User Profile" to be enabled.
• 1 - MSHtml will be hosted out-of-process and ABCpdf will attempt to load IE8 DLLs which allows you to achieve better compatibility. This requires certain IE8 DLLs to be present in the system.
• 2 - ABCpdf will attempt to perform the required configuration inside the current running process. This can be used if you cannot enable "Load User Profile" or have no access to a registry hive.

This is a setting that may be used to speed up HTML rendering of documents when AddLinks is set to true.

Fragment links within an HTML page may refer to anchor names or to element IDs. So to use the LinkPages method one has to keep track of all the IDs in the page. This can add a significant overhead for pages which contain many elements with IDs.

If you are not going to use the LinkPages method you can safely set this property to false. Indeed even if you set it to false ABCpdf will still keep track of names and IDs in anchor elements as there is little overhead associated with this subset of elements.

This is a setting that determines how images in HTML are added to a document.

The default behavior is to add all images directly as long as an ImageQuality has not been specified. This ensures that the quality and size of JPEG images is maintained, that transparent PNG images are inserted using correct transparency and that memory use is minimized.

By setting this property to one you can force images to be inserted indirectly. The HTML rendering engine will be used to decompress any images and then they will be recompressed for insertion into the PDF.