Raster images consist of a rectangular grid of small squares or dots known as pixels. For example, a photograph of a house is made up of a series of pixels colorized to represent the appearance of a house. A raster image references the pixels in a specific grid.
Raster images, like many other drawing objects, can be copied, moved, or clipped. You can modify an image with grip modes, adjust an image for contrast, clip the image with a rectangle or polygon, or use an image as a cutting edge for a trim.
The image file formats supported by the program include the most common formats used in major technical imaging application areas: computer graphics, document management, engineering, mapping, and geographic information systems (GIS). Images can be bitonal, 8-bit gray, 8-bit color, or 24-bit color. Images with 16-bit color depth are not supported.
Several image file formats support images with transparent pixels. When image transparency is set to on, the program recognizes those transparent pixels and allows graphics in the drawing area to “show through” those pixels. (In bitonal images, background pixels are treated as transparent.) Transparent images can be gray-scale or color.
Although the file name extension is listed in the following table, the file format is determined from the file contents, not from the file extension.
| Supported image file formats | ||
|---|---|---|
| Type | Description and versions | File extension |
| BMP | Windows and OS/2 bitmap format | .bmp, .dib, .rle |
| CALS-I | Mil-R-Raster I | .gp4, .mil, .rst, .cg4, .cal |
| DDS | Microsoft DirectDraw Surface | .dds |
| DOQ | USGS Digital Orthophoto Quads | .doq |
| ECW | Enhanced Compression Wavelet | .ecw |
| FLIC | FLIC Autodesk Animator Animation | .flc, .fli |
| GeoSPOT | GeoSPOT (BIL files must be accompanied with HDR and PAL files with correlation data, in the same directory) | .bil |
| HDR | High Dynamic Range Image | .hdr |
| IG4 | Image Systems Group 4 | .ig4 |
| JPEG2000 | Wavelet-based compression standard created by the Joint Photographics Expert Group . | jp2, .j2k |
| JFIF or JPEG | Joint Photographics Expert Group | .jpg, .jpeg |
| MrSID | Multiresolution Seamless Image Database | .sid |
| NITF | National Imagery Transmission Format
Note: NITF files containing elevation data require AutoCAD Raster Design
|
.nitf |
| OpenEXR | Industrial Light & Magic High-Dynamic Range image | .exr |
| PCX | Picture PC Paintbrush Picture | .pcx |
| PICT | Picture Macintosh Picture | .pct |
| PNG | Portable Network Graphic | .png |
| PSD | Adobe Photoshop Document | .psd |
| RLC | Run-Length Compressed | .rlc |
| TARGA | True Vision Raster-Based Data Format | .tga |
| TIFF | Tagged Image File Format | .tif, .tiff |