Fourth, the image storage format
The image storage format has a great influence on the digital image. The storage format is related to whether the image is compressed, the number of colors it can express, and the depth of the image pixels. Here are some of our common storage formats:
*. Jpg/*. Jpeg (Joint Photographic Expert Group)
*. Jpg/*. Jpeg is a 24-bit image file format, which is also an efficient compression format. It is a compression standard for continuous-tone still images. Its original purpose was to use a 64Kbps communication line to transmit compressed 720 × 576 resolution images. With minimal loss of resolution, the amount of memory required for the image can be reduced to 10% of its original size. Due to its high compression efficiency and standardization requirements, it has been widely used in the transmission of color faxes, still images, teleconferences, and print and news photos. However, the deleted data cannot be restored when decompressed, so *. Jpg/*. The jpeg file is not suitable for magnified viewing, and the quality of the output into print can also be affected. However, its effect on the loss of graphic images is not very large, a 16M (24-bit) *. Jpg/*. The jpeg image does not look much different from the photo, and non-professionals cannot even distinguish it. Same picture with *. jpg/ *. The files stored in the jpeg format are 1/10 to 1/20 of other types of graphic files. Under normal circumstances, *. Jpe/*. The jpes file is only a few tens of kilobytes, and the maximum number of colors can reach 24 bits.
*.tif/*.tiff(Tag Image File format)
*.tiff is a graphics file format developed by Aldus for Macintosh computers. It was first popular with the Macintosh and is now supported by mainstream image applications on Windows. Currently, it is the most widely used bitmap format on Macintosh and PC. It is very convenient to transplant *.tiff graphic images on these two hardware platforms. Most scanners can also output *.tiff format image files. The format supports up to 16M colors. Its characteristics are: the quality of the stored image is high, but the storage space it occupies is also very large, and the size is 10 times that of the *.jpeg image; the information in the subtle level is more, which is conducive to the reproduction of original tonality and color. This format has two forms of compression and non-compression, in which the compressed form uses the LZW (Lempel-Ziv-Welch) lossless compression scheme. In PhotoShop, the *.tiff format can support 24 channels, which is the only file format that can store multiple four channels in addition to the format in PhotoShop (*.psd and *.pdd). The only downside is that because of the unique variable structure of *.tiff, it is very difficult to decompress *.tiff files.
*. Pcd (Kodak PhotoCD)
*. pcd is a Photo CD file format developed by Kodak Company. Other software systems can only read it. This format is mainly used to store color scanned images on CD-ROM. It uses the YCC color mode to define the colors in the image. The Y CC color mode is a variant of the CIE color mode. The CIE color space is an international standard that defines the colors that all human eyes can observe. The YCC and CIE color spaces contain much more colors than RGS and CMYK colors for displays and printing devices. Most of the Photo CD images are of very high quality. The cost of scanning a roll of film to a Photp CD file is not high, but the quality of the scan also depends on the type of film used and the level of operation of the scanner user.
*. Eps (Encapsulated Postscript)
*. Eps is an ASCII graphics file format described in the Postscript language. It can print high-quality graphic images on a Postscript graphics printer and can represent up to 32-bit graphic images. The format is divided into PhotoShop EPS format (Adobe Illustrator Eps) and standard EPS format, which standard EPS format can be divided into graphic formats and image formats. It is worth noting that only EPS files in image format can be opened in PhotoShop. *. The eps format consists of two parts: the first part is a low-resolution image file displayed on the screen, which facilitates previewing and positioning during image processing; the second part contains separate data for each color separation. *. The eps file is stored in the form of DCS/CMYK. The file contains individual data of the four colors of CMYK, which can directly output four-color meshes. However, in addition to being more reliable on Postscript printers, the *.epsilon format has many drawbacks. First, the efficiency of storing images in the *.eps format is particularly low; second, the compression scheme in the *.eps format is also poor, and generally the same. Image by *. Tiff's LZW compression is 3 to 4 degrees smaller than the *.eps image.
*. bmp(Bitmap)
*. bmp is a Bitmap format for Windows and OS/2. The file is hardly compressed and takes up a lot of disk space. Its color storage format is 1, 4, 8 and 24 bits. The resolution can also be from 480×320 to 1024×768. This format is quite stable under Windows environment, and the image processing software under DOS and Windows supports this format. Therefore, this format is a widely used format today. However, the disadvantage is that the format file is relatively large, so it can only be used on a stand-alone machine and is not welcomed by the Internet.
The above mentioned is the storage format of the image file. Regarding the storage of the image, the size of the image is also related to the storage of the image. Here are two concepts introduced below to describe the image size: One is the physical size of the image, that is, height and width. For digital images, it is usually expressed in pixels instead of inches or millimeters. However, in a finished layout design, the size of the image is often expressed in inches. The other one refers to the size of the image file, ie how many bytes (bytes or megabytes). This involves the image's resolution, pixel depth, and maximum size. We can use the following formula to calculate the file size of a digital image: (pixel width × pixel height) × (pixel depth ÷ 8)
This is calculated as the number of bytes of the file. Dividing the number of bytes by 1024 yields kilobytes. If divided by 1024, megabytes are obtained. For example, a digital image in 24bits RGB color mode has a pixel width of 459pixels and a pixel height of 612 pixels. The file size is 823K:
(459×612)×(24÷8)=842724 bytes÷1024=823K
The image storage format has a great influence on the digital image. The storage format is related to whether the image is compressed, the number of colors it can express, and the depth of the image pixels. Here are some of our common storage formats:
*. Jpg/*. Jpeg (Joint Photographic Expert Group)
*. Jpg/*. Jpeg is a 24-bit image file format, which is also an efficient compression format. It is a compression standard for continuous-tone still images. Its original purpose was to use a 64Kbps communication line to transmit compressed 720 × 576 resolution images. With minimal loss of resolution, the amount of memory required for the image can be reduced to 10% of its original size. Due to its high compression efficiency and standardization requirements, it has been widely used in the transmission of color faxes, still images, teleconferences, and print and news photos. However, the deleted data cannot be restored when decompressed, so *. Jpg/*. The jpeg file is not suitable for magnified viewing, and the quality of the output into print can also be affected. However, its effect on the loss of graphic images is not very large, a 16M (24-bit) *. Jpg/*. The jpeg image does not look much different from the photo, and non-professionals cannot even distinguish it. Same picture with *. jpg/ *. The files stored in the jpeg format are 1/10 to 1/20 of other types of graphic files. Under normal circumstances, *. Jpe/*. The jpes file is only a few tens of kilobytes, and the maximum number of colors can reach 24 bits.
*.tif/*.tiff(Tag Image File format)
*.tiff is a graphics file format developed by Aldus for Macintosh computers. It was first popular with the Macintosh and is now supported by mainstream image applications on Windows. Currently, it is the most widely used bitmap format on Macintosh and PC. It is very convenient to transplant *.tiff graphic images on these two hardware platforms. Most scanners can also output *.tiff format image files. The format supports up to 16M colors. Its characteristics are: the quality of the stored image is high, but the storage space it occupies is also very large, and the size is 10 times that of the *.jpeg image; the information in the subtle level is more, which is conducive to the reproduction of original tonality and color. This format has two forms of compression and non-compression, in which the compressed form uses the LZW (Lempel-Ziv-Welch) lossless compression scheme. In PhotoShop, the *.tiff format can support 24 channels, which is the only file format that can store multiple four channels in addition to the format in PhotoShop (*.psd and *.pdd). The only downside is that because of the unique variable structure of *.tiff, it is very difficult to decompress *.tiff files.
*. Pcd (Kodak PhotoCD)
*. pcd is a Photo CD file format developed by Kodak Company. Other software systems can only read it. This format is mainly used to store color scanned images on CD-ROM. It uses the YCC color mode to define the colors in the image. The Y CC color mode is a variant of the CIE color mode. The CIE color space is an international standard that defines the colors that all human eyes can observe. The YCC and CIE color spaces contain much more colors than RGS and CMYK colors for displays and printing devices. Most of the Photo CD images are of very high quality. The cost of scanning a roll of film to a Photp CD file is not high, but the quality of the scan also depends on the type of film used and the level of operation of the scanner user.
*. Eps (Encapsulated Postscript)
*. Eps is an ASCII graphics file format described in the Postscript language. It can print high-quality graphic images on a Postscript graphics printer and can represent up to 32-bit graphic images. The format is divided into PhotoShop EPS format (Adobe Illustrator Eps) and standard EPS format, which standard EPS format can be divided into graphic formats and image formats. It is worth noting that only EPS files in image format can be opened in PhotoShop. *. The eps format consists of two parts: the first part is a low-resolution image file displayed on the screen, which facilitates previewing and positioning during image processing; the second part contains separate data for each color separation. *. The eps file is stored in the form of DCS/CMYK. The file contains individual data of the four colors of CMYK, which can directly output four-color meshes. However, in addition to being more reliable on Postscript printers, the *.epsilon format has many drawbacks. First, the efficiency of storing images in the *.eps format is particularly low; second, the compression scheme in the *.eps format is also poor, and generally the same. Image by *. Tiff's LZW compression is 3 to 4 degrees smaller than the *.eps image.
*. bmp(Bitmap)
*. bmp is a Bitmap format for Windows and OS/2. The file is hardly compressed and takes up a lot of disk space. Its color storage format is 1, 4, 8 and 24 bits. The resolution can also be from 480×320 to 1024×768. This format is quite stable under Windows environment, and the image processing software under DOS and Windows supports this format. Therefore, this format is a widely used format today. However, the disadvantage is that the format file is relatively large, so it can only be used on a stand-alone machine and is not welcomed by the Internet.
The above mentioned is the storage format of the image file. Regarding the storage of the image, the size of the image is also related to the storage of the image. Here are two concepts introduced below to describe the image size: One is the physical size of the image, that is, height and width. For digital images, it is usually expressed in pixels instead of inches or millimeters. However, in a finished layout design, the size of the image is often expressed in inches. The other one refers to the size of the image file, ie how many bytes (bytes or megabytes). This involves the image's resolution, pixel depth, and maximum size. We can use the following formula to calculate the file size of a digital image: (pixel width × pixel height) × (pixel depth ÷ 8)
This is calculated as the number of bytes of the file. Dividing the number of bytes by 1024 yields kilobytes. If divided by 1024, megabytes are obtained. For example, a digital image in 24bits RGB color mode has a pixel width of 459pixels and a pixel height of 612 pixels. The file size is 823K:
(459×612)×(24÷8)=842724 bytes÷1024=823K
The dumbbell, a type of free weight, it can use in home and in the gym, is a piece of equipment used in weight training. It can be used individually or in pairs, with one in each hand.
There are currently three main types of dumbbell:
Adjustable Dumbbells , Fixed-Weight Dumbbells, "Selectorized" Dumbbells .
According to different appearance techniques, it has the following types of dumbbell:
Cast Iron Dumbbells, Neoprene Dumbbells, Urethane Dumbbells, Vinyl Dumbbells and Rubber Dumbbells .
According to different shapes, it has the following types of dumbbell:
Hex Dumbbells, Round Dumbbells and Studio Dumbbells.
Dumbbells
Rubber Dumbbell,Hex Dumbbell,Plastic Dumbbells,Commercial Dumbbell
AZJ (China) Fitness Products Co., Ltd , http://www.fitness-cn.com