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File Formats |
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File Formats (a name for a specific way of arranging data, how it is written and how it may be read) JPEG- jay-peg- (The Joint Photographic Experts Group) a lossy compression technique for color images. It can reduce file size to about 5% of their normal size, some detail is lost in the compression. Used to display photographs and single alpha channel, and indexed-color, grayscale, and 16-bit and 24-bit RGB files without alpha channels. When saving an RGB image in this format, you can choose a pixel depth. PDF- Short for Portable Document Format, a file format developed by Adobe Systems. PDF captures formatting information from a variety of desktop publishing applications, making it possible to send formatted documents and have them appear on the recipientÕs monitor or printer as they were intended. To view a file in PDF format, you need Adobe Acrobat Reader, a free application distributed by Adobe Systems. Bit-Mapped Graphics File Formats: TIFF (Tagged Image File Format)- a standard file format for storing images as bit maps. It is used especially for scanned images because it can support any size, resolution, and color depth. The TIFF format supports CMYK, RGB, and grayscale with alpha channels, and Lab, indexed-color, and Bitmap files without alpha channels. TIFF also supports LZW compression. When you save an Adobe Photoshop image in TIFF, you can choose to save in a format that can be read either by IBM PC-compatible or Macintosh computers. To compress the file automatically, click the LZW Compression check box; compressing a TIFF file decreases its file size but increases the time required to open and save the file. Adobe Photoshop also reads and saves captions in TIFF files. GIF- (Graphics Interchange Format) the bit-mapped file format used by CompuServe and many other BBSs (Bulletin Board Systems) is commonly used to display indexed-color graphics and images in hypertext markup language (HTML) documents over the WWW and other online services. GIF is a LZW-compressed format designed to minimize file size and electronic transfer time. The GIF format does not support alpha channels. You can convert files to GIF format using one of the following methods:
PCX- a common graphics file format supported by many graphics programs, as well as most optical scanners and fax modems. Works on Mac and PC BMP- (as a file format-not to be confused with bit-mapped, which is a certain way graphic image are constructed) the bit-mapped file format used by Microsoft Windows Vector Graphics File Formats: PICT- a standard format for storing and exchanging graphics files. It is supported by all graphics programs that run on Macintosh. EPS (Encapsulated PostScript)- the file format for transfering PostScript language artwork between applications. EPS uses a combination of PostScript commands and TIFF or PICT formats (bit-mapped and vector). It is supported by virtually all graphic, illustration, and page-layout programs. When you open an EPS file containing vecot graphics created in another application, Photoshop rasterizes the file, converting the vector graphics to pixels (see Importing Adobe Illustrator, PDF, and EPS files). The EPS format supports alpha channels. EPS does support clipping paths. For more information, see Saving files in Photoshop EPS or DCS format. PageMaker publication format- allows reopening PageMaker template format- allows opening of a copy Photoshop format- used by that application and not suitable for import
From time to time it is important to change the format of an image. This process might include the opening, placing, or pasting of an image into a photoshop file in order to take advantage of its many save and export options. You can import files created in Adobe Illustrator, PDF, and EPS files containing vector art using these commands:
When an Illustrator, PDF, or EPS image is opened or placed in Photoshop, it is rasterized-the mathematically defined lines and curves of the vector image are converted into the pixels or bits of a bitmap image. For more on vector and bitmap images, see About bitmap images and vector graphics. To convert a multiple-page PDF file to multiple image in Photoshop format, choose File > Automate > Multi-Page PDF to PSD. To open an Abobe Illustrator, PDF, or EPS file as a new Abobe Photoshop image: 1. Choose File > Open. 2. Select the file you want to open, and click Open. If the file does not appear, for Files of Type, chose All Formats (Windows) or select Show All Files (Mac OS). 3. If you are opening a PDF file that contains multiple pages, select the page you want to open, and click OK. 4. Indicate the desired dimensions, resolution, and mode. To maintain the same height-to-width ratio, select Constrain Proportions. 5. Select Anti-aliased to minimize the jagged appearance of the artworkÕs edges as it is rasterized. 6. Click OK.
To place Adobe Illustrator, PDF, EPS artwork into an Adobe Photoshop image: 1. Open the Adobe Photoshop image in which you want to place the artwork. 2. Chose File > Place, select the file you want to place, and Click Open. 3. If you are placing a PDF file that contains multiple pages, select the page you want to place, and click OK. The placed artwork appears as a new layer inside a bounding box at the center of the Adobe Photoshop image. The artwork maintains its original aspect ratio. 4. Adjust the placed artwork. |
