img-bmp - Img, Windows Bitmap Format (bmp)
package require Tk
package require img::bmp ?1.4?
image create photo ?name?
?options?
The package img::bmp is a sub-package of Img. It can
be loaded as a part of the complete Img support, via package require
Img, or on its own, via package require img::bmp.
Like all packages of Img it does not provide new
commands, but extends the existing Tk command image so that it
supports files containing raster images in the Windows Bitmap Format (bmp).
More specifically img::bmp extends Tk's photo image
type.
The name of the new format handler is bmp. This handler
provides new additional configuration options. See section BMP
OPTIONS for more detailed explanations.
All of the above means that in a call like
- image create
photo ?name? ?options?
- [1]
- Image data in bmp format (options -data and -file) is
detected automatically.
- [2]
- The format name bmp is recognized by the option -format. In
addition the value for the option is treated as list and may contain any
of the special options listed in section BMP OPTIONS.
The handler provides an option to influence the writing of a BMP
image.
- -resolution
res
- The display resulation and/or aspect ratio property of the outputted bmp
file may be set using this option. The default values are an x and y
resolution of 74 dpi. res is a list of 2 or 3 elements and may have
one of the following formats. The values xres, yres and
unit are specified after the formats.
- res = xres
unit
- Set the same resolution for x and y. Example: Write image with a
resolution of 300dpi:
img write out.bmp -format {bmp -resolution {300 i}}
- res = xres
yres
- Set the aspect ratio only. The x resolution remains to the default value
74dpi, as the bmp format does not allow to specify the aspect ratio only.
The y resolution is set to 74*yres/xres. Example: Write
image with an aspect ratio of 1/3:
img write out.bmp -format {bmp -resolution {1 3}}
- res = xres
yres unit
- Set an independent resolution for x and y direction. Example: Write image
with a resolution of x=300dpi and y=150dpi:
img write out.bmp -format {bmp -resolution {300 100 i}}
- The used parameters are:
- float xres
(input)
- The output resolution in x direction as a float number.
- float yres
(input)
- The output resolution in x direction as a float number.
- string unit
(input)
- Unit of the given resolution numbers similar to Tk_GetPixel. Possible
units are:
- c
- pixel per centimeter.
- m
- pixel per meter.
- i
- pixel per inch.
- p
- pixel per inch/72 (Printer points).
img-bmp, img-dted, img-gif, img-ico, img-intro, img-jpeg, img-pcx,
img-pixmap, img-png, img-ppm, img-ps, img-raw, img-sgi, img-sun, img-tga,
img-tiff, img-window, img-xbm, img-xpm
Copyright (c) 1995-2009 Jan Nijtmans <nijtmans@users.sourceforge.net>