poppler::image Class Reference

#include "poppler/cpp/poppler-image.h"

Public Types
enum	format_enum {   format_invalid ,   format_mono ,   format_rgb24 ,   format_argb32 ,   format_gray8 ,   format_bgr24 }

Public Member Functions
	image ()
	image (char *idata, int iwidth, int iheight, format_enum iformat)
	image (const image &img)
	image (int iwidth, int iheight, format_enum iformat)
	~image ()
int	bytes_per_row () const
const char *	const_data () const
image	copy (const rect &r=rect()) const
char *	data ()
format_enum	format () const
int	height () const
bool	is_valid () const
image &	operator= (const image &img)
bool	save (const std::string &file_name, const std::string &out_format, int dpi=-1) const
int	width () const

Static Public Member Functions
static std::vector< std::string >	supported_image_formats ()

Detailed Description

A simple representation of image, with direct access to the data.

This class uses implicit sharing for the internal data, so it can be used as value class. This also means any non-const operation will make sure that the data used by current instance is not shared with other instances (ie detaching), copying the shared data.

Since

0.16

Member Enumeration Documentation

format_enum

enum poppler::image::format_enum

The possible formats for an image.

format_gray8 and format_bgr24 were introduced in poppler 0.65.

Constructor & Destructor Documentation

image() [1/4]

image::image

(

)

Construct an invalid image.

image() [2/4]

image::image	(	int	iwidth,
		int	iheight,
		image::format_enum	iformat
	)

Construct a new image.

It allocates the storage needed for the image data; if the allocation fails, the image is an invalid one.

Parameters

iwidth	the width for the image
iheight	the height for the image
iformat	the format for the bits of the image

image() [3/4]

image::image	(	char *	idata,
		int	iwidth,
		int	iheight,
		image::format_enum	iformat
	)

Construct a new image.

It uses the provide data buffer for the image, so you must ensure it remains valid for the whole lifetime of the image.

Parameters

idata	the buffer to use for the image
iwidth	the width for the image
iheight	the height for the image
iformat	the format for the bits of the image

image() [4/4]

image::image

(

const image &

img

)

Copy constructor.

~image()

image::~image

(

)

Destructor.

Member Function Documentation

bytes_per_row()

int image::bytes_per_row

(

)

const

Returns

the number of bytes in each row of the image

const_data()

const char * image::const_data

(

)

const

Access to the image bits.

This function provides const access to the data.

Returns

the pointer to the first pixel

copy()

image image::copy

(

const rect &

r = rect()

)

const

Copy of a slice of the image.

Parameters

r	the sub-area of this image to copy; if empty, the whole image is copied

Returns

a new image representing the specified part of the current image

data()

char * image::data

(

)

Access to the image bits.

This function will detach and copy the shared data.

Returns

the pointer to the first pixel

format()

image::format_enum image::format

(

)

const

Returns

the format of the image

height()

int image::height

(

)

const

Returns

whether the height of the image

is_valid()

bool image::is_valid

(

)

const

Image validity check.

Returns

whether the image is valid.

operator=()

image & image::operator=

(

const image &

img

)

Assignment operator.

save()

bool image::save	(	const std::string &	file_name,
		const std::string &	out_format,
		int	dpi = -1
	)		const

Saves the current image to file.

Using this function it is possible to save the image to the specified file_name, in the specified out_format and with a resolution of the specified dpi.

Image formats commonly supported are:

• PNG: png
• JPEG: jpeg, jpg
• TIFF: tiff
• PNM: pnm (with Poppler >= 0.18)

If an image format is not supported (check the result of supported_image_formats()), the saving fails.

Returns

whether the saving succeeded

supported_image_formats()

std::vector< std::string > image::supported_image_formats ( )

static

Returns

a list of the supported image formats

width()

int image::width

(

)

const

Returns

whether the width of the image