| SAS/AF Software: Class Dictionary |
To create an image data model, load the class from SASHELP.FSP.IMGDAT,
and then create an instance of the class:
imgdat_class=loadclass('sashelp.fsp.imgdat');
imgdat_id=instance(imgdat_class);
|
| Argument Values Common to Many Image Data Model Class Methods |
Units. All width, height, x and
y positions are pixel based. The upper left corner
is position 0,0.
File-Specific Attributes. The Image Data Model class supports
many file formats for reading and writing. These formats are listed below.
When you are reading in images, include the FORMAT= attribute in the method
if
- you are reading a format supported only on certain hosts
- images reside in SAS catalogs
- images are read from a system
pipe.
FORMAT= is not required in other cases, but it is always
more efficient to specify it.
When you are writing images, you must specify the FORMAT= attribute
if the LNAMEMK SCL function is not used to include the FORMAT= attribute as
part of the image pathname for the image-path
argument in the method.
|
| Supported Image File Types |
The image class supports the following image file types:
| File Type |
Description |
| BMP - Microsoft Windows Device Independent Bitmap |
supports color-mapped and true color images stored
as uncompressed or run-length encoded. BMP was developed by Microsoft Corporation
for storing images under Windows 3.0 and OS/2 operating systems. |
| CAT - SAS Catalog IMAGE entry |
|
| DIB - Microsoft Windows Device Independent Bitmap |
See the description of BMP. |
| EMF - Microsoft NT Enhanced Metafile |
|
| EPSI - Encapsulated PostScript Interchange |
is an extended version of the standard PostScript (PS) format.
Files using this format can be printed on PostScript printers and also can
be imported into other applications. Notice that EPSI files can be read but
PS files cannot. |
| GIF - Graphics Interchange Format |
supports only color-mapped images. GIF is owned by CompuServe, Inc. |
| JPEG - Joint Photographic Experts Group |
supports compression of images with the use of JPEG File Interchange
Format (JFIF) software. JFIF software is developed by the Independent JPEG
Group. |
| MET - OS/2 Metafile |
|
| PBM - Portable Bitmap Utilities |
supports gray, color, RGB, and bitmap files. The Portable Bitmap Utilities
is a set of free utility programs that were primarily developed by Jeff Poskanzer. |
| PCD - Photo CD |
Kodak Photo
CD format which supports multiple image resolutions. |
| PCL - Printer Control Language |
|
| PCX - PC Paintbrush |
supports
bitmapped, color-mapped, and true color images. PCX and PC Paintbrush are
owned by Zsoft Corporation. |
| PICT - The QuickDraw Picture Format |
supports 256 color images and bitmaps. The QuickDraw Picture Format
is owned by Apple Computer, Inc. |
| PNG - Portable Network Graphic |
supports truecolor, gray-scale, and 8-bit images. |
| PS - PostScript Image File Format |
The Image classes use only PostScript image operators. A level II PS
printer is required for color images. PostScript was developed by Adobe Systems,
Inc. |
| TGA - Targa |
supports both
true color images and color-mapped images; however, the current release of
the Image classes supports only true color TGA files. Targa is owned by Truevision,
Inc. |
| TIFF - Tagged Image File Format |
internally supports a number of compression types and image types, including
bitmapped, color-mapped, gray-scaled, and true color. TIFF was developed by
Aldus Corporation and Microsoft Corporation and is used by a wide variety
of applications. |
| WMF - Microsoft Windows Metafile |
|
| XBM - X Window Bitmaps |
supports
bitmapped images only. XBM is owned by MIT X Consortium. |
| XPM - X Window Pixmap |
is
an extended version of XBM that supports color bitmaps. |
| XWD - X Window Dump |
supports
all X visual types (bitmapped, color-mapped, and true color.) XWD is owned
by MIT X Consortium. |
|
| Image File Types and Attributes |
The following table describes the attributes for the image readers and
writers that are supported by SAS/GRAPH. You can specify an image file's attributes
in SCL functions by enclosing the attributes in quotation marks and separating
multiple attributes with blanks. The following examples include an Image Data
object example and an SCL example:
Image Data object example:
CALL SEND (imgdat_id, "_READ_", filename, "FORMAT=TIFF COMPRESS=G3FAX");
SCL example:
rc = igop(tid, "WRITE",filename,"FORMAT=TIFF COMPRESS=G3FAX");
Image Readers for Supported File Types
| File Type |
Reader Attributes |
Comment |
| BMP |
| FORMAT=BMP |
|
| COMPRESS=NONE |
Default |
| COMPRESS=RLE |
Run-length encoded |
|
| CAT |
FORMAT=CAT |
|
| DIB |
FORMAT=DIB |
only supported under Windows 3.1, Windows NT, and OS/2 operating systems |
| EMF |
FORMAT=EMF |
supported only under Windows NT and Windows 95 |
| EPSI |
FORMAT=EPSI DPI=num |
number of dots per inch that was specified when the output file was
created |
| GIF |
FORMAT=GIF |
|
| JFIF |
| FORMAT=JFIF |
required for reading
JPEG files that use JPEG File Interchange Format (JFIF). |
| DCT=mode |
selects specific
type of Discrete Cosine Transform (DCT) to use when processing the image; mode can be
- INT an integer DCT
- FAST a faster and less
accurate integer DCT
- FLOAT a slightly more accurate method that can be slower unless
the host has very fast floating point hardware
|
| GRAYSCALE |
produces a gray-scale
image even if the JPEG file is in color. This is useful for viewing on monochrome
displays. The reader runs noticeably faster in this mode. |
| VERSION |
prints the version number
and copyright messages for the Independent JPEG Group's JFIF software to the
log. |
| FAST |
enables certain recommended
processing options for fast, low quality output; equivalent to enabling ONEPASS,
DITHER=ORDERED, COLORS=216, NOSMOOTH, and DCT=FAST. |
| NOSMOOTH |
uses a faster, lower quality,
upsampling routine. |
| ONEPASS |
uses a one-pass color quantization
instead of the standard two-pass quantization. The one-pass method is faster
and needs less memory, but it produces a lower-quality image. This attribute
is ignored unless you also specify the COLORS attribute. ONEPASS is always
enabled for gray-scale output. |
| COLORS=n |
reduces the
number of colors in the image to at most n colors; n must be
in the range 2...256. |
| SCALE_RATIO=n |
scales
the output image by a factor of 1/n. Currently the scale factor
must be 1/1, 1/2, 1/4, or 1/8. This is useful when processing a large image
and only a smaller version is needed, as the reader is much faster when scaling
down the output. |
| DITHER=mode |
selects
the specific type of dithering to use color quantization; mode
can be
- FS Floyd-Steinberg dithering
- ORDERED ordered dithering
- NONE no
dithering
|
|
| MET |
FORMAT=MET |
supported only under OS/2 |
| PBM |
FORMAT=PBM |
|
| PCD |
FORMAT=PCX |
FORMAT=PCD RES= specifies the image resolution to be read. Photo CD
images have multiple resolution images in each image. Values are:
| BASE/64 |
64x96 |
| BASE/16 |
128x192 |
| BASE/4 |
256x384 |
| BASE |
512x768 (default) |
| 4BASE |
1024x1536 |
| 16BASE |
2048x3072 |
|
| PCX |
FORMAT=PCX |
not supported for writing |
| PICT |
FORMAT=PICT |
supported only in the Macintosh environment |
| PNG |
FORMAT=PNG |
|
| TGA |
FORMAT=TGA |
|
| TIFF |
FORMAT=TIFF |
|
| XBM |
FORMAT=XBM |
|
| XPM |
FORMAT=XPM |
supported only under the X Windows System under UNIX |
| XWD |
FORMAT=XWD |
|
Image Writers for Supported File Types
| File Type |
Writer Attributes |
Comment |
| BMP |
FORMAT=BMP |
|
| CAT |
| FORMAT=CAT |
|
| COMPRESS=G3FAX |
FAX CCITT Group
3 for monochrome black-and-white images (depth of 1) only |
| COMPRESS=G4FAX |
FAX CCITT Group4
for monochrome black-and-white images (depth of 1) only |
| DESC= |
'description' for catalog
description |
|
| DIB |
FORMAT=DIB |
supported only under the Windows 3.1, Windows NT, Windows 95, and OS/2
operating systems |
| EMF |
FORMAT=EMF |
supported only under Windows NT and Windows 95 |
| EPSI |
FORMAT=EPSI |
|
| GIF |
FORMAT=GIF |
|
| JFIF |
| FORMAT=JFIF |
required for reading
JPEG files that use JPEG File Interchange Format (JFIF). |
| DCT=mode |
selects specific
type of Discrete Cosine Transform (DCT) to use when processing the image; mode can be
- INT an integer DCT
- FAST a faster and less
accurate integer DCT
- FLOAT a slightly more accurate method that can be slower unless
the host has very fast floating point hardware
|
| GRAYSCALE |
produces a gray-scale
image even if the JPEG file is in color. This is useful for viewing on monochrome
displays. The reader runs noticeably faster in this mode. |
| VERSION |
prints the version number
and copyright messages for the Independent JPEG Group's JFIF software to the
log. |
| FAST |
enables certain recommended
processing options for fast, low quality output; equivalent to enabling ONEPASS,
DITHER=ORDERED, COLORS=216, NOSMOOTH, and DCT=FAST. |
| NOSMOOTH |
uses a faster, lower quality,
upsampling routine. |
| ONEPASS |
uses a one-pass color quantization
instead of the standard two-pass quantization. The one-pass method is faster
and needs less memory, but it produces a lower-quality image. This attribute
is ignored unless you also specify the COLORS attribute. ONEPASS is always
enabled for gray-scale output. |
| COLORS=n |
reduces the
number of colors in the image to at most n colors; n must be
in the range 2...256. |
| SCALE_RATIO=n |
scales
the output image by a factor of 1/n. Currently the scale factor
must be 1/1, 1/2, 1/4, or 1/8. This is useful when processing a large image
and only a smaller version is needed, as the reader is much faster when scaling
down the output. |
| DITHER=mode |
selects
the specific type of dithering to use color quantization; mode
can be
- FS Floyd-Steinberg dithering
- ORDERED ordered dithering
- NONE no
dithering
|
|
| MET |
FORMAT=MET |
supported only under OS/2 |
| PBM |
| FORMAT=PBM |
|
| COMPRESS=NONE |
text PBM file (default) |
| COMPRESS=BINARY |
binary PBM file |
| COMPRESS=RAW |
binary PBM file |
|
| PCL |
| FORMAT=PCL |
|
| DPI=num |
number of
dots per inch to be used in the output file |
| EPS |
does not reset the printer
margins; use to embed an image into another PCL document |
|
| PICT |
FORMAT=PICT |
supported only in the Macintosh environment |
| PNG |
FORMAT=PNG |
|
| PS |
| FORMAT=PS |
|
| COMPRESS=NONE |
default for color
images |
| COMPRESS=RLE |
run-length encoded;
default for gray-scale images |
| DPI=num |
number of
dots per inch to be used in the output file |
| EPS |
does not reset the printer
margins; used to embed an image in another PCL document |
| PREVIEW |
specifies whether a scaled-down,
1-bit, black-and-white preview image is written into the encapsulation
header. The preview image enables this file to be read by software (such as
SAS) that doesn't support a real PostScript reader. |
PREWIDTH=x
PREHEIGHT=y |
size of the preview image in pixels if PREVIEW is
specified (default: 25% of original size) |
| XSCALE |
directly sets width scaling
(default: calculate it) |
| YSCALE |
directly sets height scaling
(default: calculate it) |
| PAGEX |
sets output page width in
pixels (default: 612, typical 8.5-inch page) |
| PAGEY |
sets output page height in
pixels (default: 792, typical 11-inch page) |
| NOFIT |
turns off the default of
scaling an oversized image down to fit the page. Must be used with XSCALE
and YSCALE. |
|
| TIFF |
| FORMAT=TIFF |
|
| COMPRESS=NONE |
default |
| COMPRESS=G3FAX |
FAX CCITT Group
3 for monochrome black-and-white (depth of 1) images only |
| COMPRESS=G4FAX |
FAX CCITT Group
4 for monochrome black-and-white (depth of 1) images only |
|
| WMF |
FORMAT=WMF |
supported only under Windows operating systems |
| XBM |
FORMAT=XBM |
supported for writing only from interactive windows under UNIX |
| XPM |
FORMAT=XPM |
supported only under the X Windows System under UNIX |
Support for camera devices is added through the _READ_ method and the
READ command. The OPTIONS string is used to pass information to the device.
Syntax for the image object:
CALL SEND (data-object-id, '_READ_', camera, options);
Syntax for the IMGOP function:
RC = IMGOP (tid, 'READ', camera, options);
Camera indicates which camera will be
used. Two values are valid: KODAKDC40 and TWAIN.
The following table describes the attributes for a digital camera. When
you read images from a digital camera, you must include the DEVICE= attribute
in the method.
Reader Attributes for Kodak DC40 Cameras
| Device Type |
Reader Attributes |
Comment |
| CAMERA |
| DEVICE=CAMERA |
required; also requires
the use of either the PICNUM=n or TAKEPIC option. |
| DELLAST |
deletes the last image.
Can be used to take a picture and delete it from camera as it is returned.
You can put camera in a mode to delete the last image only if the camera is
empty. Changing this mode limits the number of images that the camera can
hold. Cannot be used with DELALL or PICNUM. |
| DELALL |
deletes all images on camera.
Cannot be used with DELLAST. |
| EXPOSE=setting |
shifts
exposure in relation to the auto exposure setting:
The setting
remains in effect until the exposure is reset or changed
again. A manual change on the camera behaves the same. |
| FLASH=setting |
sets
the flash unit; setting can be
The setting remains in
effect until the unit is reset or changed again.
A manual change on the camera behaves the same. |
| PICNUM=n |
gets picture
number n. Cannot be used with TAKEPIC. |
| PORT=n |
sets the serial
port number. The default is to search for and automatically detect camera. |
| RES=setting |
sets the
resolution; setting can be
You can change the resolution only on an empty camera
before the pictures
are taken. |
| RESET |
resets camera to default
values. You can reset only an empty camera. Can be used with DELALL to empty
and reset camera. |
| TAKEPIC |
takes a photo and returns
it. Cannot be used with PICNUM. |
| THUMB |
returns thumbnail size instead
of full image. |
|
Reader Attributes for TWAIN Cameras
| Device Type |
Reader Attributes |
Comment |
| CAMERA |
| DEVICE=CAMERA |
Required. |
| Type=char |
Type of
image to generate:
Default = highest supported
resolution |
| SELSRC |
enables the selection of
a data source via the TWAIN Select Source window. |
| SETCAP |
enables the setting and
modification of capabilities via the selected TWAIN data source's capability
window. |
| SCNAME=char |
TWAIN Data Source name:
Key word that matches the Product name of the
camera (if more than one TWAIN device is available). Partial matches are supported --
if the key word matches more than one camera's product name, the first match
is selected. This must be specified if you do not want to have to choose the
source from the Select Source window. The default
is the last device installed or last device selected.
Note: Product name is the name displayed
in the TWAIN Select Source window. It may not be the same as the name of the
camera. Use the SELSRC option to see possible
values. ![[cautionend]](../common/images/cautend.gif)
|
|
Support for scanner devices is added through the _READ_ method and the
READ command. The OPTIONS string is used to pass information to the device.
Syntax for the image object:
CALL SEND (data-object-id, '_READ_', scanner, options);
Syntax for the IMGOP function:
RC = IMGOP (tid, 'READ', scanner, options);
Scanner indicates which scanner will
be used. Two choices are valid: HPSCAN and TWAIN.
The following table describes the attributes for a scanner. When you
read images from a scanner, you must include the DEVICE= attribute in the
method.
Reader Attributes for HPSCAN Scanners
| Device Type |
Reader Attributes |
Comment |
| SCANNER |
| DEVICE=SCANNER |
required; supported
only under Windows 95, Windows NT, and HP/UX operating systems. |
| BRIGHT=n |
sets brightness
setting; the default is 0. |
| CONTRAST=n |
sets contrast
setting; the default is 0. This option is ignored with bitonal images. |
| DPI=n |
sets dots per
inch; the default is 200. |
| FEEDER | NOFEEDER |
specifies how
the document is scanned. FEEDER assumes there is a document feeder and produces
an error if not. NOFEEDER scans from bed and ignores the feeder if one is
attached. If neither attribute is specified, the default is to use the feeder
if attached or bed scan if not. |
| TYPE=type |
sets type
of image to generate; type can be
- BITONAL
(default)
- CMAP
- RGB
- GRAY
|
| UNITS=units |
sets size
units; units can be
|
| XDPI=n |
sets DPI for
width only. |
| XSIZE=d |
sets width
to scan (decimal value); the default is 8.5. |
| XSTART=d |
sets starting
point of scan; the default is 0. |
| YDPI=n |
sets DPI for
height only. |
| YSIZE=d |
sets height
to scan (decimal value); the default is 11. |
| YSTART=d |
sets starting
point of scan; the default is 0. |
|
Reader Attributes for TWAIN Scanners
| Device Type |
Reader Attributes |
Comment |
| SCANNER |
| DEVICE=SCANNER |
required; supported
only under Windows 95, Windows 32S, and HP/UX operating systems. |
| BRIGHT=n |
sets brightness
setting; the default is 0. |
| CONTRAST=n |
sets contrast
setting; the default is 0. This option is ignored with bitonal images. |
| DPI=n |
sets dots per
inch; the default is 200. |
| FEEDER | NOFEEDER |
specifies how
the document is scanned. FEEDER assumes there is a document feeder and produces
an error if not. NOFEEDER scans from bed and ignores the feeder if one is
attached. If neither attribute is specified, the default is to use the feeder
if attached or bed scan if not. |
| TYPE=type |
sets type
of image to generate; type can be
- BITONAL
(default)
- CMAP
- RGB
- GRAY
|
| UNITS=units |
sets size
units; units can be
|
| XDPI=n |
sets DPI for
width only. |
| XSIZE=d |
sets width
to scan (decimal value); the default is 8.5. |
| XSTART=d |
sets starting
point of scan; the default is 0. |
| YDPI=n |
sets DPI for
height only. |
| YSIZE=d |
sets height
to scan (decimal value); the default is 11. |
| YSTART=d |
sets starting
point of scan; the default is 0. |
| SELSRC |
enables the selection of
a data source via the TWAIN Select Source window. |
| SETCAP |
enables the setting and
modification of capabilities via the selected TWAIN data source's capability
window. |
| SCNAME=char |
TWAIN Data Source name:
Key word that matches the Product name of the
camera (if more than one TWAIN device is available). Partial matches are supported --
if the key word matches more than one camera's product name, the first match
is selected. This must be specified if you do not want to have to choose the
source from the Select Source window. The default
is the last device installed or last device selected.
Note: Product name is the name displayed
in the TWAIN Select Source window. It may not be the same as the name of the
camera. Use the SELSRC option to see possible
values.
|
|
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
