Common picture file formats and their respective features

One, BMP format

The BMP format is a standard image file format in the Windows operating system and can be supported by a variety of Windows applications. The feature is that the image information contained is richer and is hardly compressed. The disadvantage is that it takes too much disk space. Therefore, the current BMP on a single machine is more popular.
Second, GIF format
It is characterized by high compression ratio and less disk space, so this image format has been widely used.
In addition, in view of the actual situation in the network transmission, GIF image format also increased the fade way. Currently, many of the color animation files used on the Internet are files of this format.

But GIF has a small drawback that it cannot store more than 256 colors of images. However, this format is still on the network of the large-scale application, which and the GIF image file short, download speed, many of the same size can be used to make the image file animation and other advantages are inseparable.

Third, JPEG format

JPEG files with the extension of. jpg or. jpeg, the compression technology is very advanced, it uses lossy compression method to remove redundant images and color data, obtain a very high compression rate at the same time can display a very rich vivid image, in other words, can use the least disk space to get better image quality.

JPEG is also a very flexible format, with the ability to adjust the image quality, allowing you to compress the file with different compression ratios, and of course we can find a balance between image quality and file size.
Its application is also very extensive, especially in the network and CD-ROM books, certainly can find its shadow. At present, all kinds of browsers support JPEG image format, because the JPEG format file size is small, download speed, so that the Web page is likely to provide a large number of beautiful images in a short download time, JPEG also logically become the most popular image format on the network.

Iv. format of JPEG2000

JPEG 2000 is a new generation of still image compression technology with higher compression rates and more features.

Unlike JPEG, the JPEG2000 supports both lossy and lossless compression, while JPEG only supports lossy compression (JPEG2000). Lossless compression is useful for preserving some important images. One of the most important features of JPEG2000 is its ability to achieve progressive transmission, which is similar to GIF's "fade", that is, to transfer the contour of the image, and then gradually transfer the data, continuously improve the image quality, so that the images from hazy to clear display, and not necessarily like the current JPEG, Show slowly from top to bottom.

In addition, JPEG2000 supports the so-called "area of Interest" feature, which allows you to arbitrarily specify the compression quality of your area of interest on the image, and optionally extract the specified part first.
JPEG2000 can be used in the traditional JPEG market, such as scanners, digital cameras, etc., also in the emerging fields, such as network transmission, wireless communication and so on
V. TIFF format
TIFF is characterized by complex image formats and more storage information. Because it stores the image of a small level of information very much, the quality of the image can be improved, so it is very beneficial to the copy of the manuscript.

The format is compressed and uncompressed in two forms, where compression can be stored using the LZW lossless compression scheme. However, because the TIFF format is more complex and less compatible, sometimes your software may not recognize the TIFF file correctly (most software now solves this problem). Porting TIFF files on Mac and PC is also handy, so TIFF is now one of the most widely used image file formats on microcomputers.

Six, PSD format
PSD is actually a graphic design of Photoshop "Draft map", which contains a variety of layers, channels, masks and other design of the sample, so that the next time you open the file can modify the previous design. In the various image formats supported by Photoshop, PSD accesses much faster than other formats and is powerful.
Seven, PNG format
PNG is characterized by a rich storage format, both GIF and JPG color mode, the use of lossless compression to reduce the size of the file, display speed, just download 1/64 of the image information can display a low-resolution preview image; PNG also supports the production of transparent images, Transparent images in the production of Web page image is very useful, we can make the image background transparent, using the color information of the page itself instead of the color set to transparent, so that the image and the background of the Web page can be fused together harmoniously. The disadvantage of P Ng is that it does not support the use of animation application effects.

Eight, SWF format

The animated image in this format can represent rich multimedia forms with relatively small volumes. In the image transmission aspect, does not have to wait for the file all to download to watch, but can download the side to see, therefore is particularly suitable for the network transmission, especially in the case of poor transmission rate, but also can achieve better results. It is also proved that SWF has now been widely used in Web pages for multimedia presentations and interactive designs. In addition, the SWF animation is made from the vector technology, so no matter how many times the screen magnification, the screen will not have any damage. In summary, the work with its high-definition picture quality and small volume, by more and more web designer's favor, but also more and more become the mainstream of web animation and web image design, has become the reality of online animation standards.

Nine, SVG format

svg means scalable vector graphics. It is an open-standard vector graphics language that allows you to design exciting, high-resolution web graphics pages. Users can directly use the code to depict the image, you can use any word processing tool to open the SVG image, by changing part of the code to make the image interactive function, and can be inserted into the HTML at any time through the browser to watch.

It provides the current network of popular formats GIF and JPEG do not have the advantage: you can arbitrarily enlarge the graphical display, but never at the expense of image quality, the word in the SVG image retains an editable and searchable state; on average, SVG files are much smaller than files in JPEG and GIF formats, and are therefore fast to download.