Raster API
Keywords: Programming

## Introduction

The CUPS raster API provides a standard interface for reading and writing CUPS raster streams which are used for printing to raster printers. Because the raster format is updated from time to time, it is important to use this API to avoid incompatibilities with newer versions of CUPS.

## General Usage

The <cups/raster.h> header file must be included to use the `cupsRaster` functions.

Programs using these functions must be linked to the CUPS imaging library: libcupsimage.a, libcupsimage.so.2, libcupsimage.2.dylib, libcupsimage_s.a, or libcupsimage2.lib depending on the platform. The following command compiles myprogram.c using GCC and the CUPS imaging library:

    gcc -o myprogram myprogram.c -lcupsimage

## Compatibility

Unless otherwise specified, the raster API functions require CUPS 1.1 or higher.

## Licensing

The CUPS raster API is provided under the terms of the GNU General Public License, with exceptions for MacOS X-based programs. Please see the CUPS license agreement for more information.

## Contents

- Enumerations
- Functions
- Structures
- Types

## Enumerations

- `cups_bool_e`
- `cups_mode_e`

### cups_bool_e

#### Description

Types...

#### Values

Name | Description
--- | ---
`CUPS_FALSE` | Logical false
`CUPS_TRUE` | Logical true

### cups_mode_e

#### Description

Raster modes

#### Values

Name | Description
--- | ---
`CUPS_RASTER_READ` | Open stream for reading
`CUPS_RASTER_WRITE` | Open stream for writing

## Functions

- `cupsRasterClose()`
- `cupsRasterInterpretPPD()` CUPS 1.2
- `cupsRasterOpen()`
- `cupsRasterReadHeader()`
- `cupsRasterReadHeader2()` CUPS 1.2
- `cupsRasterReadPixels()`
- `cupsRasterWriteHeader()`
- `cupsRasterWriteHeader2()` CUPS 1.2
- `cupsRasterWritePixels()`

### cupsRasterClose()

#### Description

Close a raster stream.

#### Syntax

    void
    cupsRasterClose(
        cups_raster_t * r);

#### Arguments

Name | Description
--- | ---
`r` | Stream to close

#### Returns

Nothing.

### CUPS 1.2 cupsRasterInterpretPPD()

#### Description

Interpret PPD commands to create a page header. This function does not mark the options in the PPD using the "num_options" and "options" arguments. Instead, mark the options prior to calling cupsRasterInterpretPPD() - this allows you to do per-page options without manipulating the options array.

#### Syntax

    int
    cupsRasterInterpretPPD(
        cups_page_header2_t * h,
        ppd_file_t * ppd,
        int num_options,
        cups_option_t * options);

#### Arguments

Name | Description
--- | ---
`h` | Page header
`ppd` | PPD file
`num_options` | Number of options
`options` | Options

#### Returns

0 on success, -1 on failure

### cupsRasterOpen()

#### Description

Open a raster stream.

#### Syntax

    cups_raster_t *
    cupsRasterOpen(
        int fd,
        cups_mode_t mode);

#### Arguments

Name | Description
--- | ---
`fd` | File descriptor
`mode` | Mode

#### Returns

New stream

### cupsRasterReadHeader()

#### Description

Read a raster page header and store it in a V1 page header structure.

#### Syntax

    unsigned
    cupsRasterReadHeader(
        cups_raster_t * r,
        cups_page_header_t * h);

#### Arguments

Name | Description
--- | ---
`r` | Raster stream
`h` | Pointer to header data

#### Returns

1 on success, 0 on fail

### CUPS 1.2 cupsRasterReadHeader2()

#### Description

Read a raster page header and store it in a V2 page header structure.

#### Syntax

    unsigned
    cupsRasterReadHeader2(
        cups_raster_t * r,
        cups_page_header2_t * h);

#### Arguments

Name | Description
--- | ---
`r` | Raster stream
`h` | Pointer to header data

#### Returns

1 on success, 0 on fail

### cupsRasterReadPixels()

#### Description

Read raster pixels.

#### Syntax

    unsigned
    cupsRasterReadPixels(
        cups_raster_t * r,
        unsigned char * p,
        unsigned len);

#### Arguments

Name | Description
--- | ---
`r` | Raster stream
`p` | Pointer to pixel buffer
`len` | Number of bytes to read

#### Returns

Number of bytes read

### cupsRasterWriteHeader()

#### Description

Write a raster page header from a V1 page header structure.

#### Syntax

    unsigned
    cupsRasterWriteHeader(
        cups_raster_t * r,
        cups_page_header_t * h);

#### Arguments

Name | Description
--- | ---
`r` | Raster stream
`h` | Raster page header

#### Returns

1 on success, 0 on failure

### CUPS 1.2 cupsRasterWriteHeader2()

#### Description

Write a raster page header from a V2 page header structure.

#### Syntax

    unsigned
    cupsRasterWriteHeader2(
        cups_raster_t * r,
        cups_page_header2_t * h);

#### Arguments

Name | Description
--- | ---
`r` | Raster stream
`h` | Raster page header

#### Returns

1 on success, 0 on failure

### cupsRasterWritePixels()

#### Description

Write raster pixels.

#### Syntax

    unsigned
    cupsRasterWritePixels(
        cups_raster_t * r,
        unsigned char * p,
        unsigned len);

#### Arguments

Name | Description
--- | ---
`r` | Raster stream
`p` | Bytes to write
`len` | Number of bytes to write

#### Returns

Number of bytes written

## Structures

- `cups_page_header2_s` CUPS 1.2
- `cups_page_header_s`

### CUPS 1.2 cups_page_header2_s

#### Description

Version 2 Page Header

#### Definition

    struct cups_page_header2_s
    {
      unsigned AdvanceDistance;
      cups_adv_t AdvanceMedia;
      cups_bool_t Collate;
      cups_cut_t CutMedia;
      cups_bool_t Duplex;
      unsigned HWResolution[2];
      unsigned ImagingBoundingBox[4];
      cups_bool_t InsertSheet;
      cups_jog_t Jog;
      cups_edge_t LeadingEdge;
      cups_bool_t ManualFeed;
      unsigned Margins[2];
      char MediaClass[64];
      char MediaColor[64];
      unsigned MediaPosition;
      char MediaType[64];
      unsigned MediaWeight;
      cups_bool_t MirrorPrint;
      cups_bool_t NegativePrint;
      unsigned NumCopies;
      cups_orient_t Orientation;
      cups_bool_t OutputFaceUp;
      char OutputType[64];
      unsigned PageSize[2];
      cups_bool_t Separations;
      cups_bool_t TraySwitch;
      cups_bool_t Tumble;
      unsigned cupsBitsPerColor;
      unsigned cupsBitsPerPixel;
      float cupsBorderlessScalingFactor;
      unsigned cupsBytesPerLine;
      cups_order_t cupsColorOrder;
      cups_cspace_t cupsColorSpace;
      unsigned cupsCompression;
      unsigned cupsHeight;
      float cupsImagingBBox[4];
      unsigned cupsInteger[16];
      char cupsMarkerType[64];
      unsigned cupsMediaType;
      unsigned cupsNumColors;
      char cupsPageSizeName[64];
      float cupsPageSize[2];
      float cupsReal[16];
      char cupsRenderingIntent[64];
      unsigned cupsRowCount;
      unsigned cupsRowFeed;
      unsigned cupsRowStep;
      char cupsString[16][64];
      unsigned cupsWidth;
    };

#### Members

Name | Description
--- | ---
`AdvanceDistance` | AdvanceDistance value in points
`AdvanceMedia` | AdvanceMedia value (see above)
`Collate` | Collated copies value
`CutMedia` | CutMedia value (see above)
`Duplex` | Duplexed (double-sided) value
`HWResolution[2]` | Resolution in dots-per-inch
`ImagingBoundingBox[4]` | Pixel region that is painted (points)
`InsertSheet` | InsertSheet value
`Jog` | Jog value (see above)
`LeadingEdge` | LeadingEdge value (see above)
`ManualFeed` | ManualFeed value
`Margins[2]` | Lower-lefthand margins in points
`MediaClass[64]` | MediaClass string
`MediaColor[64]` | MediaColor string
`MediaPosition` | MediaPosition value
`MediaType[64]` | MediaType string
`MediaWeight` | MediaWeight value in grams/m^2
`MirrorPrint` | MirrorPrint value
`NegativePrint` | NegativePrint value
`NumCopies` | Number of copies to produce
`Orientation` | Orientation value (see above)
`OutputFaceUp` | OutputFaceUp value
`OutputType[64]` | OutputType string
`PageSize[2]` | Width and length of page in points
`Separations` | Separations value
`TraySwitch` | TraySwitch value
`Tumble` | Tumble value
`cupsBitsPerColor` | Number of bits for each color
`cupsBitsPerPixel` | Number of bits for each pixel
`cupsBorderlessScalingFactor` CUPS 1.2 | Scaling that was applied to page data
`cupsBytesPerLine` | Number of bytes per line
`cupsColorOrder` | Order of colors
`cupsColorSpace` | True colorspace
`cupsCompression` | Device compression to use
`cupsHeight` | Height of page image in pixels
`cupsImagingBBox[4]` CUPS 1.2 | Floating point ImagingBoundingBox * (scaling factor not applied)
`cupsInteger[16]` CUPS 1.2 | User-defined integer values
`cupsMarkerType[64]` CUPS 1.2 | Ink/toner type
`cupsMediaType` | Media type code
`cupsNumColors` CUPS 1.2 | Number of colors
`cupsPageSizeName[64]` CUPS 1.2 | PageSize name
`cupsPageSize[2]` CUPS 1.2 | Floating point PageSize (scaling * factor not applied)
`cupsReal[16]` CUPS 1.2 | User-defined floating-point values
`cupsRenderingIntent[64]` CUPS 1.2 | Color rendering intent
`cupsRowCount` | Rows per band
`cupsRowFeed` | Feed between bands
`cupsRowStep` | Spacing between lines
`cupsString[16][64]` CUPS 1.2 | User-defined string values
`cupsWidth` | Width of page image in pixels

### cups_page_header_s

#### Description

Version 1 Page Header

#### Definition

    struct cups_page_header_s
    {
      unsigned AdvanceDistance;
      cups_adv_t AdvanceMedia;
      cups_bool_t Collate;
      cups_cut_t CutMedia;
      cups_bool_t Duplex;
      unsigned HWResolution[2];
      unsigned ImagingBoundingBox[4];
      cups_bool_t InsertSheet;
      cups_jog_t Jog;
      cups_edge_t LeadingEdge;
      cups_bool_t ManualFeed;
      unsigned Margins[2];
      char MediaClass[64];
      char MediaColor[64];
      unsigned MediaPosition;
      char MediaType[64];
      unsigned MediaWeight;
      cups_bool_t MirrorPrint;
      cups_bool_t NegativePrint;
      unsigned NumCopies;
      cups_orient_t Orientation;
      cups_bool_t OutputFaceUp;
      char OutputType[64];
      unsigned PageSize[2];
      cups_bool_t Separations;
      cups_bool_t TraySwitch;
      cups_bool_t Tumble;
      unsigned cupsBitsPerColor;
      unsigned cupsBitsPerPixel;
      unsigned cupsBytesPerLine;
      cups_order_t cupsColorOrder;
      cups_cspace_t cupsColorSpace;
      unsigned cupsCompression;
      unsigned cupsHeight;
      unsigned cupsMediaType;
      unsigned cupsRowCount;
      unsigned cupsRowFeed;
      unsigned cupsRowStep;
      unsigned cupsWidth;
    };

#### Members

Name | Description
--- | ---
`AdvanceDistance` | AdvanceDistance value in points
`AdvanceMedia` | AdvanceMedia value (see above)
`Collate` | Collated copies value
`CutMedia` | CutMedia value (see above)
`Duplex` | Duplexed (double-sided) value
`HWResolution[2]` | Resolution in dots-per-inch
`ImagingBoundingBox[4]` | Pixel region that is painted (points)
`InsertSheet` | InsertSheet value
`Jog` | Jog value (see above)
`LeadingEdge` | LeadingEdge value (see above)
`ManualFeed` | ManualFeed value
`Margins[2]` | Lower-lefthand margins in points
`MediaClass[64]` | MediaClass string
`MediaColor[64]` | MediaColor string
`MediaPosition` | MediaPosition value
`MediaType[64]` | MediaType string
`MediaWeight` | MediaWeight value in grams/m^2
`MirrorPrint` | MirrorPrint value
`NegativePrint` | NegativePrint value
`NumCopies` | Number of copies to produce
`Orientation` | Orientation value (see above)
`OutputFaceUp` | OutputFaceUp value
`OutputType[64]` | OutputType string
`PageSize[2]` | Width and length of page in points
`Separations` | Separations value
`TraySwitch` | TraySwitch value
`Tumble` | Tumble value
`cupsBitsPerColor` | Number of bits for each color
`cupsBitsPerPixel` | Number of bits for each pixel
`cupsBytesPerLine` | Number of bytes per line
`cupsColorOrder` | Order of colors
`cupsColorSpace` | True colorspace
`cupsCompression` | Device compression to use
`cupsHeight` | Height of page image in pixels
`cupsMediaType` | Media type code
`cupsRowCount` | Rows per band
`cupsRowFeed` | Feed between bands
`cupsRowStep` | Spacing between lines
`cupsWidth` | Width of page image in pixels

## Types

- `cups_page_header2_t` CUPS 1.2
- `cups_page_header_t`
- `cups_raster_t`

### CUPS 1.2 cups_page_header2_t

#### Description

Version 2 Page Header

#### Definition

    typedef struct cups_page_header2_s cups_page_header2_t;

### cups_page_header_t

#### Description

Version 1 Page Header

#### Definition

    typedef struct cups_page_header_s cups_page_header_t;

### cups_raster_t

#### Description

Raster stream data

#### Definition

    typedef struct _cups_raster_s cups_raster_t;