BMP (.bmp, .dib)

Import and Export fully support the BMP standard.

Background & Context

- MIME type: image/bmp
- BMP Windows bitmap format.
- Raster image format.
- Native bitmap format of the Microsoft Windows operating system.
- BMP is an acronym derived from Bitmap.
- Binary file format.
- Stores color bitmaps at a variety of color resolutions.
- Allows different bit depths in different channels.
- Has support for color reduction palettes using up to 256 8-bit RGB colors.
- Supports transparency.
- Stores data in uncompressed or run-length encoded form.

Import & Export

Import["file.bmp"] imports a BMP file, returning an Image object.
Import["file.bmp",elem] imports the specified element from a BMP file.
The import format can be specified with Import["file","BMP"] or Import["file",{"BMP",elem,…}].
Export["file.bmp",expr] exports graphics or any other expression as an image to BMP.
Notebook and Cell expressions can be exported to BMP.
When exporting Wolfram Language graphics or arbitrary expressions to BMP, the resulting image has the same raster size as its displayed form.
Image objects are by default exported at their raster size.
Because BMP is a raster image format, all fonts are rasterized on export.
See the following reference pages for full general information:

	Import, Export	import from or export to a file
	CloudImport, CloudExport	import from or export to a cloud object
	ImportString, ExportString	import from or export to a string
	ImportByteArray, ExportByteArray	import from or export to a byte array

Notebook Interface

In the notebook front end, Insert ▶ Picture and the Open menu allow import of a BMP file into a cell.
Save Selection As exports the selected part of a notebook as a BMP file.

Import Elements

General Import elements:

	"Elements"	list of elements and options available in this file
	"Rules"	full list of rules for each element and option
	"Options"	list of rules for options, properties, and settings

Data representation elements:

	"Data"	array of color values based on the encoding given by "ColorSpace"
	"Graphics"	Graphics object representing an image
	"Image"	raster image, given as an Image object
	"RawData"	color indices, given as an integer array

Import and Export by default use the "Image" element for Windows bitmap files.
Export automatically selects the most appropriate type of BMP file to store binary, grayscale, and color images.
Export creates a BMP file with indexed color when exporting color-mapped raster graphics or if the "ColorMap" element is specified.
Advanced Import elements:

	"BitDepth"	number of bits used to encode a color channel in the file
	"Channels"	the number of color channels used in the file
	"ColorDepth"	number of bits for each pixel
	"ColorMap"	color reduction palette used in the file
	"ColorSpace"	color encoding
	"ImageCompression"	compression method used in the file
	"ImageResolution"	resolution at which the graphics should be rendered
	"ImageSize"	size of the imported BMP
	"Summary"	summary of the file

The BMP format supports the following values for "ColorDepth":

	1	palette of 2 colors
	4	color reduction palette of size 16
	8	color reduction palette of size 256
	16	typically 5 bits per color channel
	24	RGB using 8 bits per channel
	32	typically 8-bit RGB with opacity

Options

Import and Export option:
ImageSize Automatic overall image size

"ImageTopOrientation" Top orientation of the image as stored in the file
Export option:
"ImageCompression" None whether to use run-length encoding
Possible settings for "ImageCompression" are None and "RLE".

Examples

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Basic Examples (3)

Import a BMP file:

Summary of an image:

Export raster graphics to BMP:

Scope (3)

Export a binary image to BMP:

Export rasterized vector graphics to BMP:

Export a rasterized Wolfram Language expression to BMP:

Import Elements (2)

Available Elements (2)

List of available elements:

Import all elements as a list of rules:

Top

	ImageSize	Automatic	overall image size
	"ImageTopOrientation"	Top	orientation of the image as stored in the file