Detailed explanation of various formats saved in Photoshop

1.PSD (*.PSD)

PSD format is the format of Adobe Photoshop software itself. This format can store all layers, channels, guides, Information such as annotations and color modes. When saving an image, if the image contains layers, it is generally saved in Photoshop (PSD) format. The saved image will not have any layers.

PSD format will compress the file when saving to reduce the disk space occupied, but the PSD format contains more image data information (such as layers, channels, clipping paths, guides, etc.), so it is better than other format image files are still much larger. Since the PSD file retains all the original image data information, it is more convenient to modify. Most typesetting software does not support files in the PSD format. It must be converted to other file formats that take up less space and have good storage quality after the image is processed.

Layer + background intact

2.BMP (*.BMP)

The BMP file format is a A Windows or OS2 standard bitmap image file format that supports RGB, indexed color, grayscale, and bitmap style modes, but does not support Alpha channels. This file format can also support 1-24-bit formats. For 4-8-bit images, the Run Length Encodlng (RLE. Run Length Encoding) compression scheme is used. This compression scheme does not lose data and is very stable. format. The BMP format does not support CMYK mode images.

3.GIF (*.GIF)

The GIF format is a graphics format provided by CompuServe, which only saves up to 256 colors of RGB Color level, it uses LZW compression method to compress files without taking up disk space. Therefore, the GIF format is widely used in Internet HTML web documents or image transmission on the network, but it can only support 8-bit image files.

Before saving the GIF format, the image format must be converted to a color mode such as bitmap, grayscale or indexed color. The GIF format uses two saving formats, one is the CompuServe GIF format, which can support Interlace (interlaced ) saving format, allowing the image to gradually transform from blurry to clear when displayed on the Internet. Another format is GIF 89a Export. In addition to supporting Ibterlace (interlaced) features, it can also support transparent background and animation formats. It only supports image information of an Alpha channel.

Supports transparent background, but does not support transparent background. Use

4.Photoshop EPS (*.EPS) format for animation

EPS format is Compressed PostScript format, a format developed for outputting images on PostScript printers. Its biggest advantage is that it can be previewed at low resolution in the typesetting software and output at high resolution when printing. It does not support alpha channels and can support clipping paths.

EPS format supports all color modes of Photoshop and can be used to store bitmap images and phasor graphics. When storing bitmap images, you can also set the white pixels of the image to a transparent effect. It is in the bitmap Mode can support transparency.

5.JPEG (*.JPG) format

The full English name of JPEG is Jont Picture Expert Group (Joint Picture Expert Group). It is a lossy compression format. Images in this format are commonly used in image previews and some hypertext documents (HTML documents). The biggest feature of the JPEG format is that the file is relatively small and can be compressed at a high rate. It is one of the formats with the highest compression rate among all formats currently. However, during the compression and saving process, the JPEG format will lose some data that is difficult to detect with the naked eye in a manner with minimal loss. Therefore, the saved image is different from the original image and is not as good as the original image, so it is best not to use this image format for printed matter.

The JPEG format supports CMYK, RGB and grayscale color modes, but does not support the Alpha channel. When you save an image as a JPEG image format, the JPEG Options dialog box will open, from which you can select the image quality and compression ratio. Usually in most cases, choose the "Maximum" option to compress the image to produce a quality that is the same as the original image. There won't be much difference in quality, but the file size will be reduced a lot.

The background is opaque and the background is white

6.PCX (*.PCX)

The PCX image format was originally developed by the Paintbrush graphics software of ZSOFT Company. Supported image formats. The PCX format supports 1-24-bit images like the BMP format, and can save files using RLE compression. The PCX format can also support RGB, indexed color, grayscale color, grayscale and bitmap color modes, but does not support Alpha channel.

7.PDF (*.PDF)

PDF format is developed by Adobe for Windows, Mac OS, UNIX and DOS systems A document format for electronic publishing software that is suitable for different platforms. It is based on the PostScript Level12 language, so it can cover vector images and bitmap images, and supports hyperlinks.

PDF file is a file format generated by Adobe Acrobat software. This format file can store multiple pages of information and includes search and navigation functions for graphic files. Therefore, using this software does not require typesetting or graphics software to obtain a layout with mixed graphics and text. Because this format supports hypertext links, it is a file frequently used for network downloads.

The PDF format supports RGB, indexed color, CMYK, grayscale, bitmap and Lab color modes, and already supports channel, layer and other data information. And the PDF format also supports JPEG and ZIP compression formats (bitmap color mode does not support ZIP compression format saving). A dialog box will appear when saving, from which you can select the compression method. When JPEG compression is selected, you can also select different compressions. Ratio to control image quality. If you select the Save Transparency check box, you can save the image's transparency properties.

8.Raw(*.RAW)

RAW is a format of digital camera raw data, which is quite Film negatives from traditional cameras. Therefore, its color and gradation tolerance is quite broad. The biggest advantage of RAW is that it preserves the most original CCD data and puts more freedom in the hands of users. The most original and authentic information is recorded without modification or alteration, leaving broad maneuverability for post-production.

9.PICT (*.PCI) format

The characteristic of the PCI file format is that it can process large blocks of graphics of the same color. Effective compression. When an RGB color mode image is saved as a PICT format image, a dialog box will pop up, prompting you to select 16-bit or 32-pixel resolution to save the image. If you select 32-bit, the saved image file can contain channels. The PICT format supports RGB, indexed color, grayscale and bitmap color modes, and the Alpha channel is also supported in RGB mode.

10.PiXaR(*.PXR)

Perhaps only PIXAR workstation users are more familiar with the *.pxr file format. This format Supports grayscale images and RGB color images. A *.pxr image created by PIXAR workstation can be opened in PhotoShop, or the image file can be stored in *.pxr format for transfer to the workstation.

11.PNG (*.PNG)

The PNG format is a format developed by Netscape and can be used for network images, but Unlike the GIF format, which can only save 256 colors, the PNG format can save 24-bit true color images, and supports the function of transparent background and anti-aliased edges, and can compress and save images without distortion. However, since the PNG format does not fully support all browsers, it is used much less frequently on web pages than the GIF and JPEG formats. But I believe that with the development of the network and the improvement of Internet transmission, the PNG format will be a standard image format used in future web pages.

PNG format files support Alpha channel in RGB grayscale mode, but do not support Alpha channel in indexed color bitmap mode. When saving an image in PNG format, a dialog box will pop up. If the Interlaced button is selected in the dialog box, then when you use the browser to appreciate the image, it will gradually appear in a blurry to clear effect. .

Supports transparent background, with transparent background, and can be used

12. Scitex CT (*.SCT)

This format is used High-end image processing on Scitex computers. Image files stored in the SCT format are usually very large and are often used in professional color works, such as magazine advertisements.

13.TGA (*.TGA) format

The TGA format is designed for systems using ruevision video cards and is usually affected by MS- DOS color application support. The Targa format supports 24-bit RGB images (8-bit x 3 color channels) and 32-bit RGB images (8-bit x 3 color channels plus an 8-bit alpha channel). The Targa format also supports indexed color and grayscale images without an alpha channel. When storing RGB images in this format, the pixel depth can be selected.

14. TIFF (*.TIf) format

The full English name of TIFF is Tagged Image File Format (Tagged Image File Format). It is a lossless compression format. The TIFF format facilitates the exchange of image data between applications and computer platforms. Therefore, the TIFF format is a very widely used image format and can be converted between many image software and platforms. The TIFF format supports three color modes: RGB, CMYK and grayscale. It also supports the use of Channels, Layers and Clipping Paths. It can place parts of the image other than the cropping path. It becomes transparent when entering typesetting software (such as PageMaker).

When saving the file format as Basic TIFF in Photoshop, a dialog box will appear, from which you can choose the format of PC or Macintosh, and you can choose the image file saved with LZW compression when saving. The Enhanced TIFF format does not support cropping paths. You can select multiple compression methods in the Save As dialog box, such as selecting LZW, ZIP and JPEG compression methods in the Compression drop-down list to reduce the disk space occupied by the file. Although the file size can be reduced, it will increase the time it takes to open and save the file. You can also choose the format of OC or Macintosh.

Save everything, including paths, etc., but the volume is very large

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