PDFio Programming Manual v1.0.0

Michael R Sweet

Copyright © 2021 by Michael R Sweet

Contents

Introduction

PDFio is a simple C library for reading and writing PDF files. The primary goals of pdfio are:

PDFio is not concerned with rendering or viewing a PDF file, although a PDF RIP or viewer could be written using it.

PDFio is Copyright © 2021 by Michael R Sweet and is licensed under the Apache License Version 2.0 with an (optional) exception to allow linking against GPL2/LGPL2 software. See the files "LICENSE" and "NOTICE" for more information.

Requirements

PDFio requires the following to build the software:

IDE files for Xcode (macOS/iOS) and Visual Studio (Windows) are also provided.

Installing pdfio

PDFio comes with a portable makefile that will work on any POSIX-compliant system with ZLIB installed. To make it, run:

make all

To test it, run:

make test

To install it, run:

make install

If you want a shared library, run:

make all-shared
make install-shared

The default installation location is "/usr/local". Pass the prefix variable to make to install it to another location:

make install prefix=/some/other/directory

The makefile installs the pdfio header to "${prefix}/include", the library to "${prefix}/lib", the pkg-config file to "${prefix}/lib/pkgconfig", the man page to "${prefix}/share/man/man3", and the documentation to "${prefix}/share/doc/pdfio".

The makefile supports the following variables that can be specified in the make command or as environment variables:

Visual Studio Project

The Visual Studio solution ("pdfio.sln") is provided for Windows developers and generates both a static library and DLL.

Xcode Project

There is also an Xcode project ("pdfio.xcodeproj") you can use on macOS which generates a static library that will be installed under "/usr/local" with:

sudo xcodebuild install

You can reproduce this with the makefile using:

sudo make COMMONFLAGS="-Os -mmacosx-version-min=10.14 -arch x86_64 -arch arm64" install

Detecting PDFio

PDFio can be detected using the pkg-config command, for example:

if pkg-config --exists pdfio; then
    ...
fi

In a makefile you can add the necessary compiler and linker options with:

CFLAGS  +=      `pkg-config --cflags pdfio`
LIBS    +=      `pkg-config --libs pdfio`

On Windows, you need to link to the PDFIO1.LIB (DLL) library and include the zlib_native NuGet package dependency. You can also use the published pdfio_native NuGet package.

Header Files

PDFio provides a primary header file that is always used:

#include <pdfio.h>

PDFio also provides PDF content helper functions for producing PDF content that are defined in a separate header file:

#include <pdfio-content.h>

API Overview

PDFio exposes several types:

Reading PDF Files

You open an existing PDF file using the pdfioFileOpen function:

pdfio_file_t *pdf = pdfioFileOpen("myinputfile.pdf", error_cb, error_data);

where the three arguments to the function are the filename ("myinputfile.pdf"), an optional error callback function (error_cb), and an optional pointer value for the error callback function (error_data). The error callback is called for both errors and warnings and accepts the pdfio_file_t pointer, a message string, and the callback pointer value, for example:

bool
error_cb(pdfio_file_t *pdf, const char *message, void *data)
{
  (void)data; // This callback does not use the data pointer

  fprintf(stderr, "%s: %s\n", pdfioFileGetName(pdf), message);

  // Return false to treat warnings as errors
  return (false);
}

The default error callback (NULL) does the equivalent of the above.

Each PDF file contains one or more pages. The pdfioFileGetNumPages function returns the number of pages in the file while the pdfioFileGetPage function gets the specified page in the PDF file:

pdfio_file_t *pdf;   // PDF file
size_t       i;      // Looping var
size_t       count;  // Number of pages
pdfio_obj_t  *page;  // Current page

// Iterate the pages in the PDF file
for (i = 0, count = pdfioFileGetNumPages(pdf); i < count; i ++)
{
  page = pdfioFileGetPage(pdf, i);
  // do something with page
}

Each page is represented by a "page tree" object (what pdfioFileGetPage returns) that specifies information about the page and one or more "content" objects that contain the images, fonts, text, and graphics that appear on the page.

The pdfioFileClose function closes a PDF file and frees all memory that was used for it:

pdfioFileClose(pdf);

Writing PDF Files

You create a new PDF file using the pdfioFileCreate function:

pdfio_rect_t media_box = { 0.0, 0.0, 612.0, 792.0 };  // US Letter
pdfio_rect_t crop_box = { 36.0, 36.0, 576.0, 756.0 }; // w/0.5" margins

pdfio_file_t *pdf = pdfioFileCreate("myoutputfile.pdf", "2.0", &media_box, &crop_box, error_cb, error_data);

where the six arguments to the function are the filename ("myoutputfile.pdf"), PDF version ("2.0"), media box (media_box), crop box (crop_box), an optional error callback function (error_cb), and an optional pointer value for the error callback function (error_data). The units for the media and crop boxes are points (1/72nd of an inch).

Alternately you can stream a PDF file using the pdfioFileCreateOutput function:

pdfio_rect_t media_box = { 0.0, 0.0, 612.0, 792.0 };  // US Letter
pdfio_rect_t crop_box = { 36.0, 36.0, 576.0, 756.0 }; // w/0.5" margins

pdfio_file_t *pdf = pdfioFileCreateOutput(output_cb, output_ctx, "2.0", &media_box, &crop_box, error_cb, error_data);

Once the file is created, use the pdfioFileCreateObj, pdfioFileCreatePage, and pdfioPageCopy functions to create objects and pages in the file.

Finally, the pdfioFileClose function writes the PDF cross-reference and "trailer" information, closes the file, and frees all memory that was used for it.

PDF Objects

PDF objects are identified using two numbers - the object number (1 to N) and the object generation (0 to 65535) that specifies a particular version of an object. An object's numbers are returned by the pdfioObjGetNumber and pdfioObjGetGeneration functions. You can find a numbered object using the pdfioFileFindObj function.

Objects contain values (typically dictionaries) and usually an associated data stream containing images, fonts, ICC profiles, and page content. PDFio provides several accessor functions to get the value(s) associated with an object:

PDF Streams

Some PDF objects have an associated data stream, such as for pages, images, ICC color profiles, and fonts. You access the stream for an existing object using the pdfioObjOpenStream function:

pdfio_file_t *pdf = pdfioFileOpen(...);
pdfio_obj_t *obj = pdfioFileFindObj(pdf, number);
pdfio_stream_t *st = pdfioObjOpenStream(obj, true);

The first argument is the object pointer. The second argument is a boolean value that specifies whether you want to decode (typically decompress) the stream data or return it as-is.

Once you have the stream open, you can use one of several functions to read from it:

When you are done reading from the stream, call the pdfioStreamClose function:

pdfioStreamClose(st);

To create a stream for a new object, call the pdfioObjCreateStream function:

pdfio_file_t *pdf = pdfioFileCreate(...);
pdfio_obj_t *pdfioFileCreateObj(pdf, ...);
pdfio_stream_t *pdfioObjCreateStream(obj, PDFIO_FILTER_FLATE);

The first argument is the newly created object. The second argument is either PDFIO_FILTER_NONE to specify that any encoding is done by your program or PDFIO_FILTER_FLATE to specify that PDFio should Flate compress the stream.

Once you have created the stream, use any of the following functions to write to the stream:

The PDF content helper functions provide additional functions for writing specific PDF page stream commands.

When you are done writing the stream, call pdfioStreamCLose to close both the stream and the object.

PDF Content Helper Functions

PDFio includes many helper functions for embedding or writing specific kinds of content to a PDF file. These functions can be roughly grouped into ??? categories:

Color Space Functions

PDF color spaces are specified using well-known names like "DeviceCMYK", "DeviceGray", and "DeviceRGB" or using arrays that define so-called calibrated color spaces. PDFio provides several functions for embedding ICC profiles and creating color space arrays:

You can embed an ICC color profile using the pdfioFileCreateICCObjFromFile function:

pdfio_file_t *pdf = pdfioFileCreate(...);
pdfio_obj_t *icc = pdfioFileCreateICCObjFromFile(pdf, "filename.icc");

where the first argument is the PDF file and the second argument is the filename of the ICC color profile.

PDFio also includes predefined constants for creating a few standard color spaces:

pdfio_file_t *pdf = pdfioFileCreate(...);

// Create an AdobeRGB color array
pdfio_array_t *adobe_rgb = pdfioArrayCreateColorFromStandard(pdf, 3, PDFIO_CS_ADOBE);

// Create an Display P3 color array
pdfio_array_t *display_p3 = pdfioArrayCreateColorFromStandard(pdf, 3, PDFIO_CS_P3_D65);

// Create an sRGB color array
pdfio_array_t *srgb = pdfioArrayCreateColorFromStandard(pdf, 3, PDFIO_CS_SRGB);

Font Object Functions

PDF supports many kinds of fonts, including PostScript Type1, PDF Type3, TrueType/OpenType, and CID. PDFio provides two functions for creating font objects. The first is pdfioFileCreateFontObjFromBase which creates a font object for one of the base PDF fonts:

PDFio always uses the Windows CP1252 subset of Unicode for these fonts.

The second function is pdfioFileCreateFontObjFromFile which creates a font object from a TrueType/OpenType font file, for example:

pdfio_file_t *pdf = pdfioFileCreate(...);
pdfio_obj_t *arial = pdfioFileCreateFontObjFromFile(pdf, "OpenSans-Regular.ttf", false);

will embed an OpenSans Regular TrueType font using the Windows CP1252 subset of Unicode. Pass true for the third argument to embed it as a Unicode CID font instead, for example:

pdfio_file_t *pdf = pdfioFileCreate(...);
pdfio_obj_t *arial = pdfioFileCreateFontObjFromFile(pdf, "NotoSansJP-Regular.otf", true);

will embed the NotoSansJP Regular OpenType font with full support for Unicode.

Note: Not all fonts support Unicode.

Image Object Functions

PDF supports images with many different color spaces and bit depths with optional transparency. PDFio provides two helper functions for creating image objects that can be referenced in page streams. The first function is pdfioFileCreateImageObjFromData which creates an image object from data in memory, for example:

pdfio_file_t *pdf = pdfioFileCreate(...);
unsigned char data[1024 * 1024 * 4]; // 1024x1024 RGBA image data
pdfio_obj_t *img = pdfioFileCreateImageObjFromData(pdf, data, /*width*/1024, /*height*/1024, /*num_colors*/3, /*color_data*/NULL, /*alpha*/true, /*interpolate*/false);

will create an object for a 1024x1024 RGBA image in memory, using the default color space for 3 colors ("DeviceRGB"). We can use one of the color space functions to use a specific color space for this image, for example:

pdfio_file_t *pdf = pdfioFileCreate(...);

// Create an AdobeRGB color array
pdfio_array_t *adobe_rgb = pdfioArrayCreateColorFromMatrix(pdf, 3, pdfioAdobeRGBGamma, pdfioAdobeRGBMatrix, pdfioAdobeRGBWhitePoint);

// Create a 1024x1024 RGBA image using AdobeRGB
unsigned char data[1024 * 1024 * 4]; // 1024x1024 RGBA image data
pdfio_obj_t *img = pdfioFileCreateImageObjFromData(pdf, data, /*width*/1024, /*height*/1024, /*num_colors*/3, /*color_data*/adobe_rgb, /*alpha*/true, /*interpolate*/false);

The "interpolate" argument specifies whether the colors in the image should be smoothed/interpolated when scaling. This is most useful for photographs but should be false for screenshot and barcode images.

If you have a JPEG or PNG file, use the pdfioFileCreateImageObjFromFile function to copy the image into a PDF image object, for example:

pdfio_file_t *pdf = pdfioFileCreate(...);
pdfio_obj_t *img = pdfioFileCreateImageObjFromFile(pdf, "myphoto.jpg", /*interpolate*/true);

Page Dictionary Functions

PDF pages each have an associated dictionary to specify the images, fonts, and color spaces used by the page. PDFio provides functions to add these resources to the dictionary:

Page Stream Functions

PDF page streams contain textual commands for drawing on the page. PDFio provides many functions for writing these commands with the correct format and escaping, as needed:

Functions

pdfioArrayAppendArray

Add an array value to an array.

bool pdfioArrayAppendArray(pdfio_array_t *a, pdfio_array_t *value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendBinary

Add a binary string value to an array.

bool pdfioArrayAppendBinary(pdfio_array_t *a, const unsigned char *value, size_t valuelen);

Parameters

a Array
value Value
valuelen Length of value

Return Value

true on success, false on failure

pdfioArrayAppendBoolean

Add a boolean value to an array.

bool pdfioArrayAppendBoolean(pdfio_array_t *a, bool value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendDate

Add a date value to an array.

bool pdfioArrayAppendDate(pdfio_array_t *a, time_t value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendDict

Add a dictionary to an array.

bool pdfioArrayAppendDict(pdfio_array_t *a, pdfio_dict_t *value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendName

Add a name to an array.

bool pdfioArrayAppendName(pdfio_array_t *a, const char *value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendNumber

Add a number to an array.

bool pdfioArrayAppendNumber(pdfio_array_t *a, double value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendObj

Add an indirect object reference to an array.

bool pdfioArrayAppendObj(pdfio_array_t *a, pdfio_obj_t *value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayAppendString

Add a string to an array.

bool pdfioArrayAppendString(pdfio_array_t *a, const char *value);

Parameters

a Array
value Value

Return Value

true on success, false on failure

pdfioArrayCopy

Copy an array.

pdfio_array_t *pdfioArrayCopy(pdfio_file_t *pdf, pdfio_array_t *a);

Parameters

pdf PDF file
a Original array

Return Value

New array or NULL on error

pdfioArrayCreate

Create an empty array.

pdfio_array_t *pdfioArrayCreate(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

New array or NULL on error

pdfioArrayCreateColorFromICCObj

Create an ICC-based color space array.

pdfio_array_t *pdfioArrayCreateColorFromICCObj(pdfio_file_t *pdf, pdfio_obj_t *icc_object);

Parameters

pdf PDF file
icc_object ICC profile object

Return Value

Color array

pdfioArrayCreateColorFromMatrix

Create a calibrated color space array using a CIE XYZ transform matrix.

pdfio_array_t *pdfioArrayCreateColorFromMatrix(pdfio_file_t *pdf, size_t num_colors, double gamma, const double matrix[3][3], const double white_point[3]);

Parameters

pdf PDF file
num_colors Number of colors (1 or 3)
gamma Gamma value
matrix[3][3] XYZ transform
white_point[3] White point

Return Value

Color space array

pdfioArrayCreateColorFromPalette

Create an indexed color space array.

pdfio_array_t *pdfioArrayCreateColorFromPalette(pdfio_file_t *pdf, size_t num_colors, const unsigned char *colors);

Parameters

pdf PDF file
num_colors Number of colors
colors RGB values for colors

Return Value

Color array

pdfioArrayCreateColorFromPrimaries

Create a calibrated color sapce array using CIE xy primary chromacities.

pdfio_array_t *pdfioArrayCreateColorFromPrimaries(pdfio_file_t *pdf, size_t num_colors, double gamma, double wx, double wy, double rx, double ry, double gx, double gy, double bx, double by);

Parameters

pdf PDF file
num_colors Number of colors (1 or 3)
gamma Gama value
wx White point X chromacity
wy White point Y chromacity
rx Red X chromacity
ry Red Y chromacity
gx Green X chromacity
gy Green Y chromacity
bx Blue X chromacity
by Blue Y chromacity

Return Value

Color space array

pdfioArrayCreateColorFromStandard

Create a color array for a standard color space.

pdfio_array_t *pdfioArrayCreateColorFromStandard(pdfio_file_t *pdf, size_t num_colors, pdfio_cs_t cs);

Parameters

pdf PDF file
num_colors Number of colors (1 or 3)
cs Color space enumeration

Return Value

Color array

Discussion

This function creates a color array for a standard PDFIO_CS_ enumerated color space. The "num_colors" argument must be 1 for grayscale and 3 for RGB color.

pdfioArrayGetArray

Get an array value from an array.

pdfio_array_t *pdfioArrayGetArray(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetBinary

Get a binary string value from an array.

unsigned char *pdfioArrayGetBinary(pdfio_array_t *a, size_t n, size_t *length);

Parameters

a Array
n Index
length Length of string

Return Value

Value

pdfioArrayGetBoolean

Get a boolean value from an array.

bool pdfioArrayGetBoolean(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetDate

Get a date value from an array.

time_t pdfioArrayGetDate(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetDict

Get a dictionary value from an array.

pdfio_dict_t *pdfioArrayGetDict(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetName

Get a name value from an array.

const char *pdfioArrayGetName(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetNumber

Get a number from an array.

double pdfioArrayGetNumber(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetObj

Get an indirect object reference from an array.

pdfio_obj_t *pdfioArrayGetObj(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetSize

Get the length of an array.

size_t pdfioArrayGetSize(pdfio_array_t *a);

Parameters

a Array

Return Value

Length of array

pdfioArrayGetString

Get a string value from an array.

const char *pdfioArrayGetString(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value

pdfioArrayGetType

Get a value type from an array.

pdfio_valtype_t pdfioArrayGetType(pdfio_array_t *a, size_t n);

Parameters

a Array
n Index

Return Value

Value type

pdfioContentClip

Clip output to the current path.

bool pdfioContentClip(pdfio_stream_t *st, bool even_odd);

Parameters

st Stream
even_odd Even/odd fill vs. non-zero winding rule

Return Value

true on success, false on failure

pdfioContentDrawImage

Draw an image object.

bool pdfioContentDrawImage(pdfio_stream_t *st, const char *name, double x, double y, double width, double height);

Parameters

st Stream
name Image name
x X offset of image
y Y offset of image
width Width of image
height Height of image

Return Value

true on success, false on failure

Discussion

The object name must be part of the page dictionary resources, typically using the pdfioPageDictAddImage function.

pdfioContentFill

Fill the current path.

bool pdfioContentFill(pdfio_stream_t *st, bool even_odd);

Parameters

st Stream
even_odd Even/odd fill vs. non-zero winding rule

Return Value

true on success, false on failure

pdfioContentFillAndStroke

Fill and stroke the current path.

bool pdfioContentFillAndStroke(pdfio_stream_t *st, bool even_odd);

Parameters

st Stream
even_odd Even/odd fill vs. non-zero winding

Return Value

true on success, false on failure

pdfioContentMatrixConcat

Concatenate a matrix to the current graphics state.

bool pdfioContentMatrixConcat(pdfio_stream_t *st, pdfio_matrix_t m);

Parameters

st Stream
m Transform matrix

Return Value

true on success, false on failure

pdfioContentMatrixRotate

Rotate the current transform matrix.

bool pdfioContentMatrixRotate(pdfio_stream_t *st, double degrees);

Parameters

st Stream
degrees Rotation angle in degrees counter-clockwise

Return Value

true on success, false on failure

pdfioContentMatrixScale

Scale the current transform matrix.

bool pdfioContentMatrixScale(pdfio_stream_t *st, double sx, double sy);

Parameters

st Stream
sx X scale
sy Y scale

Return Value

true on success, false on failure

pdfioContentMatrixTranslate

Translate the current transform matrix.

bool pdfioContentMatrixTranslate(pdfio_stream_t *st, double tx, double ty);

Parameters

st Stream
tx X offset
ty Y offset

Return Value

true on success, false on failure

pdfioContentPathClose

Close the current path.

bool pdfioContentPathClose(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentPathCurve

Add a Bezier curve with two control points.

bool pdfioContentPathCurve(pdfio_stream_t *st, double x1, double y1, double x2, double y2, double x3, double y3);

Parameters

st Stream
x1 X position 1
y1 Y position 1
x2 X position 2
y2 Y position 2
x3 X position 3
y3 Y position 3

Return Value

true on success, false on failure

pdfioContentPathCurve13

Add a Bezier curve with an initial control point.

bool pdfioContentPathCurve13(pdfio_stream_t *st, double x1, double y1, double x3, double y3);

Parameters

st Stream
x1 X position 1
y1 Y position 1
x3 X position 3
y3 Y position 3

Return Value

true on success, false on failure

pdfioContentPathCurve23

Add a Bezier curve with a trailing control point.

bool pdfioContentPathCurve23(pdfio_stream_t *st, double x2, double y2, double x3, double y3);

Parameters

st Stream
x2 X position 2
y2 Y position 2
x3 X position 3
y3 Y position 3

Return Value

true on success, false on failure

pdfioContentPathLineTo

Add a straight line to the current path.

bool pdfioContentPathLineTo(pdfio_stream_t *st, double x, double y);

Parameters

st Stream
x X position
y Y position

Return Value

true on success, false on failure

pdfioContentPathMoveTo

Start a new subpath.

bool pdfioContentPathMoveTo(pdfio_stream_t *st, double x, double y);

Parameters

st Stream
x X position
y Y position

Return Value

true on success, false on failure

pdfioContentPathRect

Add a rectangle to the current path.

bool pdfioContentPathRect(pdfio_stream_t *st, double x, double y, double width, double height);

Parameters

st Stream
x X offset
y Y offset
width Width
height Height

Return Value

true on success, false on failure

pdfioContentRestore

Restore a previous graphics state.

bool pdfioContentRestore(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentSave

Save the current graphics state.

bool pdfioContentSave(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentSetDashPattern

Set the stroke pattern.

bool pdfioContentSetDashPattern(pdfio_stream_t *st, double phase, double on, double off);

Parameters

st Stream
phase Phase (offset within pattern)
on On length
off Off length

Return Value

true on success, false on failure

pdfioContentSetFillColorDeviceCMYK

Set device CMYK fill color.

bool pdfioContentSetFillColorDeviceCMYK(pdfio_stream_t *st, double c, double m, double y, double k);

Parameters

st Stream
c Cyan value (0.0 to 1.0)
m Magenta value (0.0 to 1.0)
y Yellow value (0.0 to 1.0)
k Black value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetFillColorDeviceGray

Set the device gray fill color.

bool pdfioContentSetFillColorDeviceGray(pdfio_stream_t *st, double g);

Parameters

st Stream
g Gray value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetFillColorDeviceRGB

Set the device RGB fill color.

bool pdfioContentSetFillColorDeviceRGB(pdfio_stream_t *st, double r, double g, double b);

Parameters

st Stream
r Red value (0.0 to 1.0)
g Green value (0.0 to 1.0)
b Blue value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetFillColorGray

Set the calibrated gray fill color.

bool pdfioContentSetFillColorGray(pdfio_stream_t *st, double g);

Parameters

st Stream
g Gray value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetFillColorRGB

Set the calibrated RGB fill color.

bool pdfioContentSetFillColorRGB(pdfio_stream_t *st, double r, double g, double b);

Parameters

st Stream
r Red value (0.0 to 1.0)
g Green value (0.0 to 1.0)
b Blue value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetFillColorSpace

Set the fill colorspace.

bool pdfioContentSetFillColorSpace(pdfio_stream_t *st, const char *name);

Parameters

st Stream
name Color space name

Return Value

true on success, false on failure

pdfioContentSetFlatness

Set the flatness tolerance.

bool pdfioContentSetFlatness(pdfio_stream_t *st, double flatness);

Parameters

st Stream
flatness Flatness value (0.0 to 100.0)

Return Value

true on success, false on failure

pdfioContentSetLineCap

Set the line ends style.

bool pdfioContentSetLineCap(pdfio_stream_t *st, pdfio_linecap_t lc);

Parameters

st Stream
lc Line cap value

Return Value

true on success, false on failure

pdfioContentSetLineJoin

Set the line joining style.

bool pdfioContentSetLineJoin(pdfio_stream_t *st, pdfio_linejoin_t lj);

Parameters

st Stream
lj Line join value

Return Value

true on success, false on failure

pdfioContentSetLineWidth

Set the line width.

bool pdfioContentSetLineWidth(pdfio_stream_t *st, double width);

Parameters

st Stream
width Line width value

Return Value

true on success, false on failure

pdfioContentSetMiterLimit

Set the miter limit.

bool pdfioContentSetMiterLimit(pdfio_stream_t *st, double limit);

Parameters

st Stream
limit Miter limit value

Return Value

true on success, false on failure

pdfioContentSetStrokeColorDeviceCMYK

Set the device CMYK stroke color.

bool pdfioContentSetStrokeColorDeviceCMYK(pdfio_stream_t *st, double c, double m, double y, double k);

Parameters

st Stream
c Cyan value (0.0 to 1.0)
m Magenta value (0.0 to 1.0)
y Yellow value (0.0 to 1.0)
k Black value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetStrokeColorDeviceGray

Set the device gray stroke color.

bool pdfioContentSetStrokeColorDeviceGray(pdfio_stream_t *st, double g);

Parameters

st Stream
g Gray value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetStrokeColorDeviceRGB

Set the device RGB stroke color.

bool pdfioContentSetStrokeColorDeviceRGB(pdfio_stream_t *st, double r, double g, double b);

Parameters

st Stream
r Red value (0.0 to 1.0)
g Green value (0.0 to 1.0)
b Blue value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetStrokeColorGray

Set the calibrated gray stroke color.

bool pdfioContentSetStrokeColorGray(pdfio_stream_t *st, double g);

Parameters

st Stream
g Gray value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetStrokeColorRGB

Set the calibrated RGB stroke color.

bool pdfioContentSetStrokeColorRGB(pdfio_stream_t *st, double r, double g, double b);

Parameters

st Stream
r Red value (0.0 to 1.0)
g Green value (0.0 to 1.0)
b Blue value (0.0 to 1.0)

Return Value

true on success, false on failure

pdfioContentSetStrokeColorSpace

Set the stroke color space.

bool pdfioContentSetStrokeColorSpace(pdfio_stream_t *st, const char *name);

Parameters

st Stream
name Color space name

Return Value

true on success, false on failure

pdfioContentSetTextCharacterSpacing

Set the spacing between characters.

bool pdfioContentSetTextCharacterSpacing(pdfio_stream_t *st, double spacing);

Parameters

st Stream
spacing Character spacing

Return Value

true on success, false on failure

pdfioContentSetTextFont

Set the text font and size.

bool pdfioContentSetTextFont(pdfio_stream_t *st, const char *name, double size);

Parameters

st Stream
name Font name
size Font size

Return Value

true on success, false on failure

pdfioContentSetTextLeading

Set text leading (line height) value.

bool pdfioContentSetTextLeading(pdfio_stream_t *st, double leading);

Parameters

st Stream
leading Leading (line height) value

Return Value

true on success, false on failure

pdfioContentSetTextMatrix

Set the text transform matrix.

bool pdfioContentSetTextMatrix(pdfio_stream_t *st, pdfio_matrix_t m);

Parameters

st Stream
m Transform matrix

Return Value

true on success, false on failure

pdfioContentSetTextRenderingMode

Set the text rendering mode.

bool pdfioContentSetTextRenderingMode(pdfio_stream_t *st, pdfio_textrendering_t mode);

Parameters

st Stream
mode Text rendering mode

Return Value

true on success, false on failure

pdfioContentSetTextRise

Set the text baseline offset.

bool pdfioContentSetTextRise(pdfio_stream_t *st, double rise);

Parameters

st Stream
rise Y offset

Return Value

true on success, false on failure

pdfioContentSetTextWordSpacing

Set the inter-word spacing.

bool pdfioContentSetTextWordSpacing(pdfio_stream_t *st, double spacing);

Parameters

st Stream
spacing Spacing between words

Return Value

true on success, false on failure

pdfioContentSetTextXScaling

Set the horizontal scaling value.

bool pdfioContentSetTextXScaling(pdfio_stream_t *st, double percent);

Parameters

st Stream
percent Horizontal scaling in percent

Return Value

true on success, false on failure

pdfioContentStroke

Stroke the current path.

bool pdfioContentStroke(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentTextBegin

Begin a text block.

bool pdfioContentTextBegin(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentTextEnd

End a text block.

bool pdfioContentTextEnd(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentTextMoveLine

Move to the next line and offset.

bool pdfioContentTextMoveLine(pdfio_stream_t *st, double tx, double ty);

Parameters

st Stream
tx X offset
ty Y offset

Return Value

true on success, false on failure

pdfioContentTextMoveTo

Offset within the current line.

bool pdfioContentTextMoveTo(pdfio_stream_t *st, double tx, double ty);

Parameters

st Stream
tx X offset
ty Y offset

Return Value

true on success, false on failure

pdfioContentTextNextLine

Move to the next line.

bool pdfioContentTextNextLine(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioContentTextShow

Show text.

bool pdfioContentTextShow(pdfio_stream_t *st, bool unicode, const char *s);

Parameters

st Stream
unicode Unicode text?
s String to show

Return Value

true on success, false on failure

Discussion

This function shows some text in a PDF content stream. The "unicode" argument specifies that the current font maps to full Unicode. The "s" argument specifies a UTF-8 encoded string.

pdfioContentTextShowJustified

Show justified text.

bool pdfioContentTextShowJustified(pdfio_stream_t *st, bool unicode, size_t num_fragments, const double *offsets, const char *const *fragments);

Parameters

st Stream
unicode Unicode text?
num_fragments Number of text fragments
offsets Text offsets before fragments
fragments Text fragments

Return Value

true on success, false on failure

Discussion

This function shows some text in a PDF content stream. The "unicode" argument specifies that the current font maps to full Unicode. The "fragments" argument specifies an array of UTF-8 encoded strings.

pdfioContentTextShowf

bool pdfioContentTextShowf(pdfio_stream_t *st, bool unicode, const char *format, ...);

Parameters

st Stream
unicode Unicode text?
format printf-style format string
... Additional arguments as needed

Return Value

Show formatted text.

This function shows some text in a PDF content stream. The "unicode" argument specifies that the current font maps to full Unicode. The "format" argument specifies a UTF-8 encoded printf-style format string.

pdfioDictCopy

Copy a dictionary to a PDF file.

pdfio_dict_t *pdfioDictCopy(pdfio_file_t *pdf, pdfio_dict_t *dict);

Parameters

pdf PDF file
dict Original dictionary

Return Value

New dictionary

pdfioDictCreate

Create a dictionary to hold key/value pairs.

pdfio_dict_t *pdfioDictCreate(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

New dictionary

pdfioDictGetArray

Get a key array value from a dictionary.

pdfio_array_t *pdfioDictGetArray(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetBinary

Get a key binary string value from a dictionary.

unsigned char *pdfioDictGetBinary(pdfio_dict_t *dict, const char *key, size_t *length);

Parameters

dict Dictionary
key Key
length Length of value

Return Value

Value

pdfioDictGetBoolean

Get a key boolean value from a dictionary.

bool pdfioDictGetBoolean(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetDate

Get a date value from a dictionary.

time_t pdfioDictGetDate(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetDict

Get a key dictionary value from a dictionary.

pdfio_dict_t *pdfioDictGetDict(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetName

Get a key name value from a dictionary.

const char *pdfioDictGetName(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetNumber

Get a key number value from a dictionary.

double pdfioDictGetNumber(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetObj

Get a key indirect object value from a dictionary.

pdfio_obj_t *pdfioDictGetObj(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetRect

Get a key rectangle value from a dictionary.

pdfio_rect_t *pdfioDictGetRect(pdfio_dict_t *dict, const char *key, pdfio_rect_t *rect);

Parameters

dict Dictionary
key Key
rect Rectangle

Return Value

Rectangle

pdfioDictGetString

Get a key string value from a dictionary.

const char *pdfioDictGetString(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value

pdfioDictGetType

Get a key value type from a dictionary.

pdfio_valtype_t pdfioDictGetType(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

Value type

pdfioDictSetArray

Set a key array in a dictionary.

bool pdfioDictSetArray(pdfio_dict_t *dict, const char *key, pdfio_array_t *value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetBinary

Set a key binary string in a dictionary.

bool pdfioDictSetBinary(pdfio_dict_t *dict, const char *key, const unsigned char *value, size_t valuelen);

Parameters

dict Dictionary
key Key
value Value
valuelen Length of value

Return Value

true on success, false on failure

pdfioDictSetBoolean

Set a key boolean in a dictionary.

bool pdfioDictSetBoolean(pdfio_dict_t *dict, const char *key, bool value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetDate

Set a date value in a dictionary.

bool pdfioDictSetDate(pdfio_dict_t *dict, const char *key, time_t value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetDict

Set a key dictionary in a dictionary.

bool pdfioDictSetDict(pdfio_dict_t *dict, const char *key, pdfio_dict_t *value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetName

Set a key name in a dictionary.

bool pdfioDictSetName(pdfio_dict_t *dict, const char *key, const char *value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetNull

Set a key null in a dictionary.

bool pdfioDictSetNull(pdfio_dict_t *dict, const char *key);

Parameters

dict Dictionary
key Key

Return Value

true on success, false on failure

pdfioDictSetNumber

Set a key number in a dictionary.

bool pdfioDictSetNumber(pdfio_dict_t *dict, const char *key, double value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetObj

Set a key indirect object reference in a dictionary.

bool pdfioDictSetObj(pdfio_dict_t *dict, const char *key, pdfio_obj_t *value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetRect

Set a key rectangle in a dictionary.

bool pdfioDictSetRect(pdfio_dict_t *dict, const char *key, pdfio_rect_t *value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetString

Set a key literal string in a dictionary.

bool pdfioDictSetString(pdfio_dict_t *dict, const char *key, const char *value);

Parameters

dict Dictionary
key Key
value Value

Return Value

true on success, false on failure

pdfioDictSetStringf

Set a key formatted string in a dictionary.

bool pdfioDictSetStringf(pdfio_dict_t *dict, const char *key, const char *format, ...);

Parameters

dict Dictionary
key Key
format printf-style format string
... Additional arguments as needed

Return Value

true on success, false on failure

pdfioFileClose

Close a PDF file and free all memory used for it.

bool pdfioFileClose(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

true on success and false on failure

pdfioFileCreate

Create a PDF file.

pdfio_file_t *pdfioFileCreate(const char *filename, const char *version, pdfio_rect_t *media_box, pdfio_rect_t *crop_box, pdfio_error_cb_t error_cb, void *error_data);

Parameters

filename Filename
version PDF version number or NULL for default (2.0)
media_box Default MediaBox for pages
crop_box Default CropBox for pages
error_cb Error callback or NULL for default
error_data Error callback data, if any

Return Value

PDF file or NULL on error

Discussion

This function creates a new PDF file. The "filename" argument specifies the name of the PDF file to create.

The "version" argument specifies the PDF version number for the file or NULL for the default ("2.0").

The "media_box" and "crop_box" arguments specify the default MediaBox and CropBox for pages in the PDF file - if NULL then a default "Universal" size of 8.27x11in (the intersection of US Letter and ISO A4) is used.

The "error_cb" and "error_data" arguments specify an error handler callback and its data pointer - if NULL the default error handler is used that writes error messages to stderr.

pdfioFileCreateArrayObj

Create a new object in a PDF file containing an array.

pdfio_obj_t *pdfioFileCreateArrayObj(pdfio_file_t *pdf, pdfio_array_t *array);

Parameters

pdf PDF file
array Object array

Return Value

New object

Discussion

This function creates a new object with an array value in a PDF file. You must call pdfioObjClose to write the object to the file.

pdfioFileCreateFontObjFromBase

Create one of the base 14 PDF fonts.

pdfio_obj_t *pdfioFileCreateFontObjFromBase(pdfio_file_t *pdf, const char *name);

Parameters

pdf PDF file
name Font name

Return Value

Font object

Discussion

This function creates one of the base 14 PDF fonts. The "name" parameter specifies the font nane:

Base fonts always use the Windows CP1252 (ISO-8859-1 with additional characters such as the Euro symbol) subset of Unicode.

pdfioFileCreateFontObjFromFile

Add a font object to a PDF file.

pdfio_obj_t *pdfioFileCreateFontObjFromFile(pdfio_file_t *pdf, const char *filename, bool unicode);

Parameters

pdf PDF file
filename Filename
unicode Force Unicode

Return Value

Font object

Discussion

This function embeds a TrueType/OpenType font into a PDF file. The "unicode" parameter controls whether the font is encoded for two-byte characters (potentially full Unicode, but more typically a subset) or to only support the Windows CP1252 (ISO-8859-1 with additional characters such as the Euro symbol) subset of Unicode.

pdfioFileCreateICCObjFromFile

Add an ICC profile object to a PDF file.

pdfio_obj_t *pdfioFileCreateICCObjFromFile(pdfio_file_t *pdf, const char *filename, size_t num_colors);

Parameters

pdf PDF file
filename Filename
num_colors Number of color components (1, 3, or 4)

Return Value

Object

pdfioFileCreateImageObjFromData

Add image object(s) to a PDF file from memory.

pdfio_obj_t *pdfioFileCreateImageObjFromData(pdfio_file_t *pdf, const unsigned char *data, size_t width, size_t height, size_t num_colors, pdfio_array_t *color_data, bool alpha, bool interpolate);

Parameters

pdf PDF file
data Pointer to image data
width Width of image
height Height of image
num_colors Number of colors
color_data Colorspace data or NULL for default
alpha true if data contains an alpha channel
interpolate Interpolate image data?

Return Value

Object

Discussion

This function creates image object(s) in a PDF file from a data buffer in memory. The "data" parameter points to the image data as 8-bit color values. The "width" and "height" parameters specify the image dimensions. The "num_colors" parameter specifies the number of color components (1 for grayscale, 3 for RGB, and 4 for CMYK) and the "alpha" parameter specifies whether each color tuple is followed by an alpha value. The "color_data" parameter specifies an optional color space array for the image - if NULL, the image is encoded in the corresponding device color space. The "interpolate" parameter specifies whether to interpolate when scaling the image on the page.

Note: When creating an image object with alpha, a second image object is created to hold the "soft mask" data for the primary image.

pdfioFileCreateImageObjFromFile

Add an image object to a PDF file from a file.

pdfio_obj_t *pdfioFileCreateImageObjFromFile(pdfio_file_t *pdf, const char *filename, bool interpolate);

Parameters

pdf PDF file
filename Filename
interpolate Interpolate image data?

Return Value

Object

Discussion

This function creates an image object in a PDF file from a JPEG or PNG file. The "filename" parameter specifies the name of the JPEG or PNG file, while the "interpolate" parameter specifies whether to interpolate when scaling the image on the page.

Note: Currently PNG support is limited to grayscale, RGB, or indexed files without interlacing or alpha. Transparency (masking) based on color/index is supported.

pdfioFileCreateObj

Create a new object in a PDF file.

pdfio_obj_t *pdfioFileCreateObj(pdfio_file_t *pdf, pdfio_dict_t *dict);

Parameters

pdf PDF file
dict Object dictionary

Return Value

New object

pdfioFileCreateOutput

Create a PDF file through an output callback.

pdfio_file_t *pdfioFileCreateOutput(pdfio_output_cb_t output_cb, void *output_ctx, const char *version, pdfio_rect_t *media_box, pdfio_rect_t *crop_box, pdfio_error_cb_t error_cb, void *error_data);

Parameters

output_cb Output callback
output_ctx Output context
version PDF version number or NULL for default (2.0)
media_box Default MediaBox for pages
crop_box Default CropBox for pages
error_cb Error callback or NULL for default
error_data Error callback data, if any

Return Value

PDF file or NULL on error

Discussion

This function creates a new PDF file that is streamed though an output callback. The "output_cb" and "output_ctx" arguments specify the output callback and its context pointer which is called whenever data needs to be written:

ssize_t
output_cb(void *output_ctx, const void *buffer, size_t bytes)
{
// Write buffer to output and return the number of bytes written
}
The "version" argument specifies the PDF version number for the file or NULL for the default ("2.0").

The "media_box" and "crop_box" arguments specify the default MediaBox and CropBox for pages in the PDF file - if NULL then a default "Universal" size of 8.27x11in (the intersection of US Letter and ISO A4) is used.

The "error_cb" and "error_data" arguments specify an error handler callback and its data pointer - if NULL the default error handler is used that writes error messages to stderr.

Note: Files created using this API are slightly larger than those created using the pdfioFileCreate function since stream lengths are stored as indirect object references.

pdfioFileCreatePage

Create a page in a PDF file.

pdfio_stream_t *pdfioFileCreatePage(pdfio_file_t *pdf, pdfio_dict_t *dict);

Parameters

pdf PDF file
dict Page dictionary

Return Value

Contents stream

pdfioFileFindObj

Find an object using its object number.

pdfio_obj_t *pdfioFileFindObj(pdfio_file_t *pdf, size_t number);

Parameters

pdf PDF file
number Object number (1 to N)

Return Value

Object or NULL if not found

Discussion

This differs from pdfioFileGetObj which takes an index into the list of objects while this function takes the object number.

pdfioFileGetAuthor

Get the author for a PDF file.

const char *pdfioFileGetAuthor(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Author or NULL for none

pdfioFileGetCreationDate

Get the creation date for a PDF file.

time_t pdfioFileGetCreationDate(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Creation date or 0 for none

pdfioFileGetCreator

Get the creator string for a PDF file.

const char *pdfioFileGetCreator(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Creator string or NULL for none

pdfioFileGetID

Get the PDF file's ID strings.

pdfio_array_t *pdfioFileGetID(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Array with binary strings

pdfioFileGetKeywords

Get the keywords for a PDF file.

const char *pdfioFileGetKeywords(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Keywords string or NULL for none

pdfioFileGetName

Get a PDF's filename.

const char *pdfioFileGetName(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Filename

pdfioFileGetNumObjs

Get the number of objects in a PDF file.

size_t pdfioFileGetNumObjs(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Number of objects

pdfioFileGetNumPages

Get the number of pages in a PDF file.

size_t pdfioFileGetNumPages(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Number of pages

pdfioFileGetObj

Get an object from a PDF file.

pdfio_obj_t *pdfioFileGetObj(pdfio_file_t *pdf, size_t n);

Parameters

pdf PDF file
n Object index (starting at 0)

Return Value

Object

pdfioFileGetPage

Get a page object from a PDF file.

pdfio_obj_t *pdfioFileGetPage(pdfio_file_t *pdf, size_t n);

Parameters

pdf PDF file
n Page index (starting at 0)

Return Value

Object

pdfioFileGetProducer

Get the producer string for a PDF file.

const char *pdfioFileGetProducer(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Producer string or NULL for none

pdfioFileGetSubject

Get the subject for a PDF file.

const char *pdfioFileGetSubject(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Subject or NULL for none

pdfioFileGetTitle

Get the title for a PDF file.

const char *pdfioFileGetTitle(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Title or NULL for none

pdfioFileGetVersion

Get the PDF version number for a PDF file.

const char *pdfioFileGetVersion(pdfio_file_t *pdf);

Parameters

pdf PDF file

Return Value

Version number or NULL

pdfioFileOpen

Open a PDF file for reading.

pdfio_file_t *pdfioFileOpen(const char *filename, pdfio_password_cb_t password_cb, void *password_data, pdfio_error_cb_t error_cb, void *error_data);

Parameters

filename Filename
password_cb Password callback or NULL for none
password_data Password callback data, if any
error_cb Error callback or NULL for default
error_data Error callback data, if any

Return Value

PDF file

Discussion

This function opens an existing PDF file. The "filename" argument specifies the name of the PDF file to create.

The "password_cb" and "password_data" arguments specify a password callback and its data pointer for PDF files that use one of the standard Adobe "security" handlers. The callback returns a password string or NULL to cancel the open. If NULL is specified for the callback function and the PDF file requires a password, the open will always fail.

The "error_cb" and "error_data" arguments specify an error handler callback and its data pointer - if NULL the default error handler is used that writes error messages to stderr.

pdfioFileSetAuthor

Set the author for a PDF file.

void pdfioFileSetAuthor(pdfio_file_t *pdf, const char *value);

Parameters

pdf PDF file
value Value

pdfioFileSetCreationDate

Set the creation date for a PDF file.

void pdfioFileSetCreationDate(pdfio_file_t *pdf, time_t value);

Parameters

pdf PDF file
value Value

pdfioFileSetCreator

Set the creator string for a PDF file.

void pdfioFileSetCreator(pdfio_file_t *pdf, const char *value);

Parameters

pdf PDF file
value Value

pdfioFileSetKeywords

Set the keywords string for a PDF file.

void pdfioFileSetKeywords(pdfio_file_t *pdf, const char *value);

Parameters

pdf PDF file
value Value

pdfioFileSetSubject

Set the subject for a PDF file.

void pdfioFileSetSubject(pdfio_file_t *pdf, const char *value);

Parameters

pdf PDF file
value Value

pdfioFileSetTitle

Set the title for a PDF file.

void pdfioFileSetTitle(pdfio_file_t *pdf, const char *value);

Parameters

pdf PDF file
value Value

pdfioImageGetBytesPerLine

Get the number of bytes to read for each line.

size_t pdfioImageGetBytesPerLine(pdfio_obj_t *obj);

Parameters

obj Image object

Return Value

Number of bytes per line

pdfioImageGetHeight

Get the height of an image object.

double pdfioImageGetHeight(pdfio_obj_t *obj);

Parameters

obj Image object

Return Value

Height in lines

pdfioImageGetWidth

Get the width of an image object.

double pdfioImageGetWidth(pdfio_obj_t *obj);

Parameters

obj Image object

Return Value

Width in columns

pdfioObjClose

Close an object, writing any data as needed to the PDF file.

bool pdfioObjClose(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

true on success, false on failure

pdfioObjCopy

Copy an object to another PDF file.

pdfio_obj_t *pdfioObjCopy(pdfio_file_t *pdf, pdfio_obj_t *srcobj);

Parameters

pdf PDF file
srcobj Object to copy

Return Value

New object or NULL on error

pdfioObjCreateStream

Create an object (data) stream for writing.

pdfio_stream_t *pdfioObjCreateStream(pdfio_obj_t *obj, pdfio_filter_t filter);

Parameters

obj Object
filter Type of compression to apply

Return Value

Stream or NULL on error

pdfioObjGetArray

Get the array associated with an object.

pdfio_array_t *pdfioObjGetArray(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Array or NULL on error

pdfioObjGetDict

Get the dictionary associated with an object.

pdfio_dict_t *pdfioObjGetDict(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Dictionary or NULL on error

pdfioObjGetGeneration

Get the object's generation number.

unsigned short pdfioObjGetGeneration(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Generation number (0 to 65535)

pdfioObjGetLength

Get the length of the object's (data) stream.

size_t pdfioObjGetLength(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Length in bytes or 0 for none

pdfioObjGetNumber

Get the object's number.

size_t pdfioObjGetNumber(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Object number (1 to 9999999999)

pdfioObjGetSubtype

Get an object's subtype.

const char *pdfioObjGetSubtype(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Object subtype

pdfioObjGetType

Get an object's type.

const char *pdfioObjGetType(pdfio_obj_t *obj);

Parameters

obj Object

Return Value

Object type

pdfioObjOpenStream

Open an object's (data) stream for reading.

pdfio_stream_t *pdfioObjOpenStream(pdfio_obj_t *obj, bool decode);

Parameters

obj Object
decode Decode/decompress data?

Return Value

Stream or NULL on error

pdfioPageCopy

Copy a page to a PDF file.

bool pdfioPageCopy(pdfio_file_t *pdf, pdfio_obj_t *srcpage);

Parameters

pdf PDF file
srcpage Source page

Return Value

true on success, false on failure

pdfioPageDictAddColorSpace

Add a color space to the page dictionary.

bool pdfioPageDictAddColorSpace(pdfio_dict_t *dict, const char *name, pdfio_array_t *data);

Parameters

dict Page dictionary
name Color space name
data Color space array

Return Value

true on success, false on failure

Discussion

This function adds a named color space to the page dictionary.

The names "DefaultCMYK", "DefaultGray", and "DefaultRGB" specify the default device color space used for the page.

The "data" array contains a calibrated, indexed, or ICC-based color space array that was created using the pdfioArrayCreateCalibratedColorFromMatrix, pdfioArrayCreateCalibratedColorFromPrimaries, pdfioArrayCreateICCBasedColor, or pdfioArrayCreateIndexedColor functions.

pdfioPageDictAddFont

Add a font object to the page dictionary.

bool pdfioPageDictAddFont(pdfio_dict_t *dict, const char *name, pdfio_obj_t *obj);

Parameters

dict Page dictionary
name Font name
obj Font object

Return Value

true on success, false on failure

pdfioPageDictAddImage

Add an image object to the page dictionary.

bool pdfioPageDictAddImage(pdfio_dict_t *dict, const char *name, pdfio_obj_t *obj);

Parameters

dict Page dictionary
name Image name
obj Image object

Return Value

true on success, false on failure

pdfioStreamClose

Close a (data) stream in a PDF file.

bool pdfioStreamClose(pdfio_stream_t *st);

Parameters

st Stream

Return Value

true on success, false on failure

pdfioStreamConsume

Consume bytes from the stream.

bool pdfioStreamConsume(pdfio_stream_t *st, size_t bytes);

Parameters

st Stream
bytes Number of bytes to consume

Return Value

true on success, false on EOF

pdfioStreamGetToken

Read a single PDF token from a stream.

bool pdfioStreamGetToken(pdfio_stream_t *st, char *buffer, size_t bufsize);

Parameters

st Stream
buffer String buffer
bufsize Size of string buffer

Return Value

true on success, false on EOF

pdfioStreamPeek

Peek at data in a stream.

ssize_t pdfioStreamPeek(pdfio_stream_t *st, void *buffer, size_t bytes);

Parameters

st Stream
buffer Buffer
bytes Size of buffer

Return Value

Bytes returned or -1 on error

pdfioStreamPrintf

Write a formatted string to a stream.

bool pdfioStreamPrintf(pdfio_stream_t *st, const char *format, ...);

Parameters

st Stream
format printf-style format string
... Additional arguments as needed

Return Value

true on success, false on failure

pdfioStreamPutChar

Write a single character to a stream.

bool pdfioStreamPutChar(pdfio_stream_t *st, int ch);

Parameters

st Stream
ch Character

Return Value

true on success, false on failure

pdfioStreamPuts

Write a literal string to a stream.

bool pdfioStreamPuts(pdfio_stream_t *st, const char *s);

Parameters

st Stream
s Literal string

Return Value

true on success, false on failure

pdfioStreamRead

Read data from a stream.

ssize_t pdfioStreamRead(pdfio_stream_t *st, void *buffer, size_t bytes);

Parameters

st Stream
buffer Buffer
bytes Bytes to read

Return Value

Number of bytes read or -1 on error

Discussion

This function reads data from a stream. When reading decoded image data from a stream, you must read whole scanlines. The pdfioImageGetBytesPerLine function can be used to determine the proper read length.

pdfioStreamWrite

Write data to a stream.

bool pdfioStreamWrite(pdfio_stream_t *st, const void *buffer, size_t bytes);

Parameters

st Stream
buffer Data to write
bytes Number of bytes to write

Return Value

true on success or false on failure

pdfioStringCreate

Create a durable literal string.

char *pdfioStringCreate(pdfio_file_t *pdf, const char *s);

Parameters

pdf PDF file
s Nul-terminated string

Return Value

Durable string pointer or NULL on error

Discussion

This function creates a literal string associated with the PDF file "pdf". The "s" string points to a nul-terminated C string.

NULL is returned on error, otherwise a char * that is valid until pdfioFileClose is called.

pdfioStringCreatef

Create a durable formatted string.

char *pdfioStringCreatef(pdfio_file_t *pdf, const char *format, ...);

Parameters

pdf PDF file
format printf-style format string
... Additional args as needed

Return Value

Durable string pointer or NULL on error

Discussion

This function creates a formatted string associated with the PDF file "pdf". The "format" string contains printf-style format characters.

NULL is returned on error, otherwise a char * that is valid until pdfioFileClose is called.

Data Types

pdfio_array_t

Array of PDF values

typedef struct _pdfio_array_s pdfio_array_t;

pdfio_cs_t

Standard color spaces

typedef enum pdfio_cs_e pdfio_cs_t;

pdfio_dict_t

Key/value dictionary

typedef struct _pdfio_dict_s pdfio_dict_t;

pdfio_error_cb_t

Error callback

typedef bool (*pdfio_error_cb_t)(pdfio_file_t *pdf, const char *message, void *data);

pdfio_file_t

PDF file

typedef struct _pdfio_file_s pdfio_file_t;

pdfio_filter_t

Compression/decompression filters for streams

typedef enum pdfio_filter_e pdfio_filter_t;

pdfio_linecap_t

Line capping modes

typedef enum pdfio_linecap_e pdfio_linecap_t;

pdfio_linejoin_t

Line joining modes

typedef enum pdfio_linejoin_e pdfio_linejoin_t;

pdfio_matrix_t[3][2]

Transform matrix

typedef double pdfio_matrix_t[3][2];

pdfio_obj_t

Numbered object in PDF file

typedef struct _pdfio_obj_s pdfio_obj_t;

pdfio_output_cb_t

Output callback for pdfioFileCreateOutput

typedef ssize_t (*pdfio_output_cb_t)(void *ctx const void *data size_t datalen);

pdfio_password_cb_t

Password callback for pdfioFileOpen

typedef const char *(*pdfio_password_cb_t)(void *data const char *filename);

pdfio_rect_t

PDF rectangle

typedef struct pdfio_rect_s pdfio_rect_t;

pdfio_stream_t

Object data stream in PDF file

typedef struct _pdfio_stream_s pdfio_stream_t;

pdfio_textrendering_t

Text rendering modes

typedef enum pdfio_textrendering_e pdfio_textrendering_t;

pdfio_valtype_t

PDF value types

typedef enum pdfio_valtype_e pdfio_valtype_t;

Structures

pdfio_rect_s

PDF rectangle

struct pdfio_rect_s {
    double x1;
    double x2;
    double y1;
    double y2;
};

Members

x1 Lower-left X coordinate
x2 Upper-right X coordinate
y1 Lower-left Y coordinate
y2 Upper-right Y coordinate

Constants

pdfio_cs_e

Standard color spaces

Constants

PDFIO_CS_ADOBE AdobeRGB 1998
PDFIO_CS_P3_D65 Display P3
PDFIO_CS_SRGB sRGB

pdfio_filter_e

Compression/decompression filters for streams

Constants

PDFIO_FILTER_ASCII85 ASCII85Decode filter (reading only)
PDFIO_FILTER_ASCIIHEX ASCIIHexDecode filter (reading only)
PDFIO_FILTER_CCITTFAX CCITTFaxDecode filter
PDFIO_FILTER_CRYPT Encryption filter
PDFIO_FILTER_DCT DCTDecode (JPEG) filter
PDFIO_FILTER_FLATE FlateDecode filter
PDFIO_FILTER_JBIG2 JBIG2Decode filter
PDFIO_FILTER_JPX JPXDecode filter (reading only)
PDFIO_FILTER_LZW LZWDecode filter (reading only)
PDFIO_FILTER_NONE No filter
PDFIO_FILTER_RUNLENGTH RunLengthDecode filter (reading only)

pdfio_linecap_e

Line capping modes

Constants

PDFIO_LINECAP_BUTT Butt ends
PDFIO_LINECAP_ROUND Round ends
PDFIO_LINECAP_SQUARE Square ends

pdfio_linejoin_e

Line joining modes

Constants

PDFIO_LINEJOIN_BEVEL Bevel joint
PDFIO_LINEJOIN_MITER Miter joint
PDFIO_LINEJOIN_ROUND Round joint

pdfio_textrendering_e

Text rendering modes

Constants

PDFIO_TEXTRENDERING_FILL Fill text
PDFIO_TEXTRENDERING_FILL_AND_STROKE Fill then stroke text
PDFIO_TEXTRENDERING_FILL_AND_STROKE_PATH Fill then stroke text and add to path
PDFIO_TEXTRENDERING_FILL_PATH Fill text and add to path
PDFIO_TEXTRENDERING_INVISIBLE Don't fill or stroke (invisible)
PDFIO_TEXTRENDERING_STROKE Stroke text
PDFIO_TEXTRENDERING_STROKE_PATH Stroke text and add to path
PDFIO_TEXTRENDERING_TEXT_PATH Add text to path (invisible)

pdfio_valtype_e

PDF value types

Constants

PDFIO_VALTYPE_ARRAY Array
PDFIO_VALTYPE_BINARY Binary data
PDFIO_VALTYPE_BOOLEAN Boolean
PDFIO_VALTYPE_DATE Date/time
PDFIO_VALTYPE_DICT Dictionary
PDFIO_VALTYPE_INDIRECT Indirect object (N G obj)
PDFIO_VALTYPE_NAME Name
PDFIO_VALTYPE_NONE No value, not set
PDFIO_VALTYPE_NULL Null object
PDFIO_VALTYPE_NUMBER Number (integer or real)
PDFIO_VALTYPE_STRING String