#include <PDFRasterizer.h>

Public Types
enum	Type { e_BuiltIn, e_GDIPlus }

enum	OverprintPreviewMode { e_op_off = 0, e_op_on, e_op_pdfx_on }

enum	ColorPostProcessMode { e_postprocess_none = 0, e_postprocess_invert, e_postprocess_gradient_map, e_postprocess_night_mode }

typedef void(*	ErrorReportProc )(const char message, void data)

Public Member Functions
	PDFRasterizer (Type type=e_BuiltIn)

	~PDFRasterizer ()

std::vector< unsigned char >	Rasterize (Page &page, int width, int height, int stride, int num_comps, bool demult, const Common::Matrix2D &device_mtx, const Rect clip=0, const Rect scrl_clip_regions=0, bool *cancel=0)

void	Rasterize (Page &page, UChar in_out_image_buffer, int width, int height, int stride, int num_comps, bool demult, const Common::Matrix2D &device_mtx, const Rect clip=0, const Rect scrl_clip_regions=0, bool cancel=0)

std::vector< Separation >	RasterizeSeparations (Page &page, int width, int height, const Common::Matrix2D &mtx, const Rect clip, volatile bool cancel)

void	Rasterize (Page &page, void hdc, const Common::Matrix2D &device_mtx, const Rect clip=0, int dpi=-1, bool *cancel=0)

void	SetDrawAnnotations (bool render_annots)

void	SetHighlightFields (bool highlight_fields)

void	SetDrawUIElements (bool draw_ui_elements)

void	SetAntiAliasing (bool enable_aa)

void	SetPathHinting (bool enable_hinting)

void	SetThinLineAdjustment (bool pixel_grid_fit, bool stroke_adjust)

void	SetThinLineScaling (double scaling)

void	SetNightModeTuning (double contrast, double saturation, double flipness)

void	SetImageSmoothing (bool smoothing_enabled=true, bool hq_image_resampling=false)

void	SetCaching (bool enabled=true)

void	SetGamma (double expgamma)

void	SetOCGContext (OCG::Context *ctx)

void	SetPrintMode (bool is_printing)

void	SetOverprint (OverprintPreviewMode op)

void	SetErrorReportProc (ErrorReportProc error_proc, void *data)

void	SetRasterizerType (Type type)

Type	GetRasterizerType ()

void	SetColorPostProcessMode (ColorPostProcessMode mode)

ColorPostProcessMode	GetColorPostProcessMode () const

void	UpdateBuffer ()

void	Destroy ()

Detailed Description

PDFRasterizer is a low-level PDF rasterizer.

The main purpose of this class is to convert PDF pages to raster images (or bitmaps).

Note: PDFRasterizer is a relatively low-level class. If you need to convert PDF page to an image format or a Bitmap, consider using PDF::PDFDraw. Similarly, if you are building an interactive PDF viewing application you may want to use PDF::PDFView instead.

Definition at line 85 of file PDFRasterizer.h.

Member Typedef Documentation

typedef void(* pdftron::PDF::PDFRasterizer::ErrorReportProc)(const char *message, void *data)

Error handling. A type of callback function (or a delegate in .NET terminology) that is called in case an error is encountered during rendering.

Definition at line 423 of file PDFRasterizer.h.

Member Enumeration Documentation

enum pdftron::PDF::PDFRasterizer::ColorPostProcessMode

ColorPostProcessMode is used to modify colors after rendering.

Enumerator
e_postprocess_none
e_postprocess_invert
e_postprocess_gradient_map
e_postprocess_night_mode

Definition at line 461 of file PDFRasterizer.h.

enum pdftron::PDF::PDFRasterizer::OverprintPreviewMode

Determines if overprint is used. e_op_on: overprint is always on; e_op_off: overprint is always off. e_op_pdfx_on: overprint is on only for PDF/X files.

Enumerator
e_op_off
e_op_on
e_op_pdfx_on

Definition at line 114 of file PDFRasterizer.h.

enum pdftron::PDF::PDFRasterizer::Type

PDFNet includes two separate rasterizer implementations utilizing different graphics libraries.

The default rasterizer is 'e_BuiltIn' which is a high-quality, anti-aliased and platform independent rasterizer. This rasterizer is available on all supported platforms.

On Windows platforms, PDFNet also includes GDI+ based rasterizer. (deprecated and will be removed in a future version of PDFNet) This rasterizer is included mainly to provide vector output for printing, for EMF/WMF export, etc. For plain image rasterization we recommend using the built-in rasterizer.

Enumerator
e_BuiltIn	high-quality, platform independent rasterizer.
e_GDIPlus	GDI+ based rasterizer. (Deprecated)

Definition at line 103 of file PDFRasterizer.h.

Constructor & Destructor Documentation

pdftron::PDF::PDFRasterizer::PDFRasterizer ( Type type = e_BuiltIn )

PDFRasterizer constructor and destructor

pdftron::PDF::PDFRasterizer::~PDFRasterizer ( )

Member Function Documentation

void pdftron::PDF::PDFRasterizer::Destroy ( )

Frees the native memory of the object.

ColorPostProcessMode pdftron::PDF::PDFRasterizer::GetColorPostProcessMode ( ) const

Returns: the current color post processing mode.

Type pdftron::PDF::PDFRasterizer::GetRasterizerType ( )

Returns: the type of current rasterizer.

Note: This method is deprecated, since the GDI+ rasterizer itself is deprecated and will be removed in a future version of PDFNet. It is strongly recommended to use the built-in rasterizer and to use the XPS print path where vector conversion is needed.

std::vector<unsigned char> pdftron::PDF::PDFRasterizer::Rasterize	(	Page &	page,
		int	width,
		int	height,
		int	stride,
		int	num_comps,
		bool	demult,
		const Common::Matrix2D &	device_mtx,
		const Rect *	clip = `0`,
		const Rect *	scrl_clip_regions = `0`,
		bool *	cancel = `0`
	)

Draws the page into a given memory buffer.

Note: This method is available on all platforms and in all rasterizer implementations.

Parameters

page	The page to rasterize.
in_out_image_buffer	A pointer to a memory buffer. The buffer must contain at least (stride * height) bytes.
width	The width of the target image in pixels.
height	The height of the target image in pixels (the number of rows).
stride	Stride determines the physical width (in bytes) of one row in memory. If this value is negative the direction of the Y axis is inverted. The absolute value of stride is of importance, because it allows rendering in buffers where rows are padded in memory (e.g. in Windows bitmaps are padded on 4 byte boundaries). Besides allowing rendering on the whole buffer stride parameter can be used for rendering in a rectangular subset of a buffer.
num_comps	The number (4 or 5) representing the number of color components in the device color space. For BGR+Alpha set this parameter to 4, and for CMYK+Alpha use 5. If other values are set, exceptions will be thrown.
demult	- Specifies if the alpha is de-multiplied from the resulting color components.
device_mtx	Device transformation matrix that maps PDF page from PDF user space into device coordinate space (e.g. pixel space). PDF user space is represented in page units, where one unit corresponds to 1/72 of an inch.
clip	Optional parameter defining the clip region for the page. If the parameter is null or is not specified, PDFRasterizer uses page's crop box as a default clip region.
scrl_clp_regions	Optional parameter reserved for a future use.
cancel	An optional variable that can be used to stop the rendering thread.

Sample code:

*   float drawing_scale = 2: 
*   Common::Matrix2D mtx(drawing_scale, 0, 0, drawing_scale, 0, 0);
*   PDF::Rect bbox(page.GetMediaBox());
*   bbox.Normalize();
*   int width = int(bbox.Width() * drawing_scale); 
*   int height = int(bbox.Height() * drawing_scale);
* 
*   // Stride is represented in bytes and is aligned on 4 byte 
*   // boundary so that you can render directly to GDI bitmap.
*   // A negative value for stride can be used to flip the image 
*   // upside down.
*   int comps = 4;  // for BGRA
*   int stride = ((width * comps + 3) / 4) * 4;
*
*   // buf is a memory buffer containing at least (stride*height) bytes.
*    memset(ptr, 0xFF, height*stride);  // Clear the background to opaque white paper color.
* 
*   PDFRasterizer rast;
*   rast.Rasterize(page, buf, width, height, stride, 4, false, mtx);
* 

void pdftron::PDF::PDFRasterizer::Rasterize	(	Page &	page,
		UChar *	in_out_image_buffer,
		int	width,
		int	height,
		int	stride,
		int	num_comps,
		bool	demult,
		const Common::Matrix2D &	device_mtx,
		const Rect *	clip = `0`,
		const Rect *	scrl_clip_regions = `0`,
		bool *	cancel = `0`
	)

void pdftron::PDF::PDFRasterizer::Rasterize	(	Page &	page,
		void *	hdc,
		const Common::Matrix2D &	device_mtx,
		const Rect *	clip = `0`,
		int	dpi = `-1`,
		bool *	cancel = `0`
	)

Draws the contents of the page to a given device context.

This method can be used to send raster or GDI output to arbitrary Windows device context (e.g. memory bitmap device, printer device, or EMF/WMF record).

See also PDF::PDFDraw::DrawInRect()

Note: this method is only supported on Windows platforms. If your application is running on a Windows platform, you can select GDI+ rasterizer with SetRasterizerType() and e_GDIPlus type.

Parameters

page	The page to rasterize.
hdc	Device context (i.e. HDC structure).
device_mtx	Device transformation matrix that maps PDF page from PDF user space into device coordinate space (e.g. pixel space). PDF user space is represented in page units, where one unit corresponds to 1/72 of an inch.
clip	Optional parameter defining the clip region for the page. In the parameter is null or is not specified, PDFRasterizer uses page's crop box as a default clip region.
dpi	Optional parameter used to specify the resolution of the rasterized bitmap. This parameter is used only for built-in rasterizer. If the parameter is not specified or is less than zero, PDFNet will query the target device to determine the output resolution.
cancel	An optional variable that can be used to stop the rendering thread.

Note: This method is deprecated, since the GDI+ rasterizer itself is deprecated and will be removed in a future version of PDFNet. It is recommended to use the built-in rasterizer via other Rasterize methods or utilize the XPS print path through Convert::ToXps or Print::StartPrintJob instead.

std::vector<Separation> pdftron::PDF::PDFRasterizer::RasterizeSeparations	(	Page &	page,
		int	width,
		int	height,
		const Common::Matrix2D &	mtx,
		const Rect *	clip,
		volatile bool *	cancel
	)

Draws the page into a given memory buffer.

Note: This method is available on all platforms and in all rasterizer implementations.

Parameters

page	The page to rasterize.
width	The width of the target image in pixels.
height	The height of the target image in pixels (the number of rows).
mtx	Device transformation matrix that maps PDF page from PDF user space into device coordinate space (e.g. pixel space). PDF user space is represented in page units, where one unit corresponds to 1/72 of an inch.
clip	Optional parameter defining the clip region for the page. If the parameter is null or is not specified, PDFRasterizer uses page's crop box as a default clip region.
cancel	An optional variable that can be used to stop the rendering thread.

void pdftron::PDF::PDFRasterizer::SetAntiAliasing ( bool enable_aa )

Enable or disable anti-aliasing.

Anti-Aliasing is a technique used to improve the visual quality of images when displaying them on low resolution devices (for example, low DPI computer monitors).

Anti-aliasing is enabled by default.

void pdftron::PDF::PDFRasterizer::SetCaching ( bool enabled = true )

Enables or disables caching. Caching can improve the rendering performance in cases where the same page will be drawn multiple times.

Parameters

enabled - if true PDFRasterizer will cache frequently used graphics objects.

void pdftron::PDF::PDFRasterizer::SetColorPostProcessMode ( ColorPostProcessMode mode )

Set the color post processing transformation. This transform is applied to the rasterized bitmap as the final step in the rasterization process, and is applied directly to the resulting bitmap (disregarding any color space information). Color post processing only supported for RGBA output.

Parameters

mode	is the specific transform to be applied

void pdftron::PDF::PDFRasterizer::SetDrawAnnotations ( bool render_annots )

Enable or disable annotation and forms rendering. By default, annotations and forms are rendered.

Parameters

render_annots True to draw annotations, false otherwise.

void pdftron::PDF::PDFRasterizer::SetDrawUIElements ( bool draw_ui_elements )

Enable or disable drawing ui elements. Default is disabled.

Parameters

draw_ui_elements true to draw ui elements, false otherwise.

void pdftron::PDF::PDFRasterizer::SetErrorReportProc	(	ErrorReportProc	error_proc,
		void *	data
	)

Sets the error handling function to be called in case an error is encountered during page rendering.

Parameters

error_proc	Error handling callback function (or delegate in .NET)
data	Custom data to be passed as a second parameter to 'error_proc'.

void pdftron::PDF::PDFRasterizer::SetGamma ( double expgamma )

Sets the gamma factor used for anti-aliased rendering.

Parameters

expgamma is the exponent value of gamma function. Typical values are in the range from 0.1 to 3.

Gamma correction can be used to improve the quality of anti-aliased image output and can (to some extent) decrease the appearance common anti-aliasing artifacts (such as pixel width lines between polygons).

Note: Gamma correction is used only in the built-in rasterizer.

void pdftron::PDF::PDFRasterizer::SetHighlightFields ( bool highlight_fields )

Enable or disable highlighting form fields. Default is disabled.

Parameters

highlight_fields true to highlight, false otherwise.

void pdftron::PDF::PDFRasterizer::SetImageSmoothing	(	bool	smoothing_enabled = `true`,
		bool	hq_image_resampling = `false`
	)

Enable or disable image smoothing.

The rasterizer allows a tradeoff between rendering quality and rendering speed. This function can be used to indicate the preference between rendering speed and quality.

Note: image smoothing option has effect only if the source image has higher resolution that the output resolution of the image on the rasterized page. PDFNet automatically controls at what resolution/zoom factor, 'image smoothing' needs to take effect.

Parameters

smoothing_enabled	True to enable image smoothing, false otherwise.
hq_image_resampling	True to use a higher quality (but slower) smoothing algorithm image smoothing is enabled and hq_image_resampling is false.

void pdftron::PDF::PDFRasterizer::SetNightModeTuning	(	double	contrast,
		double	saturation,
		double	flipness
	)

This setting controls the contrast, saturation and flipness of a rendered PDF when night mode is set. By default no additional tuning is done.

Parameters

contrast	change the difference in luminance or color that makes an object distinguishable from other objects.
saturation	change the color intensity.
flipness	controls the inversion of colors when rendered.

Note: values range from 0.0 to 1.0

void pdftron::PDF::PDFRasterizer::SetOCGContext ( OCG::Context * ctx )

Sets the Optional Content Group (OCG) context that should be used when rendering the page. This function can be used to selectively render optional content (such as PDF layers) based on the states of optional content groups in the given context.

Parameters

ctx	Optional Content Group (OCG) context, or NULL if the rasterizer should render all content on the page.

void pdftron::PDF::PDFRasterizer::SetOverprint ( OverprintPreviewMode op )

Enable or disable support for overprint and overprint simulation. Overprint is a device dependent feature and the results will vary depending on the output color space and supported colorants (i.e. CMYK, CMYK+spot, RGB, etc).

By default overprint is only enabled for PDF/X files.

Parameters

op	e_op_on: always enabled; e_op_off: always disabled; e_op_pdfx_on: enabled for PDF/X files only.

void pdftron::PDF::PDFRasterizer::SetPathHinting ( bool enable_hinting )

Enable or disable path hinting.

Parameters

enable_hinting if true path hinting is enabled. Path hinting is used to slightly adjust paths in order to avoid or alleviate artifacts of hair line cracks between certain graphical elements. This option is turned on by default.

void pdftron::PDF::PDFRasterizer::SetPrintMode ( bool is_printing )

Tells the rasterizer to render the page 'print' mode. Certain page elements (such as annotations or OCG-s) are meant to be visible either on the screen or on the printed paper but not both. A common example, is the "Submit" button on electronic forms.

Parameters

is_printing set to true is the page should be rendered in print mode. By default, print mode flag is set to false.

void pdftron::PDF::PDFRasterizer::SetRasterizerType ( Type type )

Sets the core graphics library used for rasterization and rendering. Using this method it is possible to quickly switch between different implementations. By default, PDFNet uses a built-in, high-quality, and platform independent rasterizer.

Parameters

type	Rasterizer type.

Note: This method is deprecated, since the GDI+ rasterizer itself is deprecated and will be removed in a future version of PDFNet. It is strongly recommended to use the built-in rasterizer and to use the XPS print path where vector conversion is needed.

void pdftron::PDF::PDFRasterizer::SetThinLineAdjustment	(	bool	pixel_grid_fit,
		bool	stroke_adjust
	)

Set thin line adjustment parameters.

Parameters

pixel_grid_fit	if true (horizontal/vertical) thin lines will be snapped to integer pixel positions. This helps make thin lines look sharper and clearer. This option is turned off by default and it only works if path hinting is enabled.
stroke_adjust	if true auto stroke adjustment is enabled. Currently, this would make lines with sub-pixel width to be one-pixel wide. This option is turned on by default.

void pdftron::PDF::PDFRasterizer::SetThinLineScaling ( double scaling )

This setting controls the thickness of zero-width lines when rendered. In a PDF, a line width of zero denotes the thinnest line that can be rendered at device resolution: 1 device pixel wide. However, on high-resolution devices, a single pixel can be nearly invisible.

Parameters

scaling use this setting to increase the apparent thickness of these zero-width lines. 1.0 (1 pixel wide)

void pdftron::PDF::PDFRasterizer::UpdateBuffer ( )

This function is typically called for progressive rendering, in which we don't want to stop the main rendering thread. Since the rendering thread may modify separation channels, we don't consider separations in progressive rendering.

The documentation for this class was generated from the following file:

PDF/PDFRasterizer.h

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation