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Acrobat to Img - Convert Acrobat files to Img files (acrobat2img,acrobattoimg)

Types of Bitmap Img Formats

A Bitmap Img is an array of bits that specifies the color of each pixel in a rectangular array of pixels. The number of bits devoted to an individual pixel determines the number of colors that can be assigned to that pixel. For example, if each pixel is represented by 4 bits, then a given pixel can be assigned one of 16 different colors (2^4 = 16). The following table shows a few examples of the number of colors that can be assigned to a pixel represented by a given number of bits.

Bits per pixel Number of colors that can be assigned to a pixel
1 2^1 = 2
2 2^2 = 4
4 2^4 = 16
8 2^8 = 256
16 2^16 = 65,536
24 2^24 = 16, 777, 216

Disk files that store Img bitmaps usually contain one or more information blocks that store information such as number of bits per pixel, number of pixels in each row, and number of rows in the array. Such a file might also contain a color table (sometimes called a color palette). A color table maps numbers in the bitmap Img to specific colors. The following illustration shows an enlarged image along with its bitmap Img and color table. Each pixel is represented by a 4-bit number, so there are 2^4 = 16 colors in the color table. Each color in the table is represented by a 24-bit number: 8 bits for red, 8 bits for green, and 8 bits for blue. The numbers are shown in hexadecimal (base 16) form: A = 10, B = 11, C = 12, D = 13, E = 14, F = 15.

Look at the pixel in row 3, column 5 of the image. The corresponding number in the bitmap Img is 1. The color table tells us that 1 represents the color red, so the pixel is red. All the entries in the top row of the bitmap are 3. The color table tells us that 3 represents blue, so all the pixels in the top row of the image are blue.

Note  Some bitmap Img files are stored in bottom-up format; the numbers in the first row of the bitmap Img correspond to the pixels in the bottom row of the image.

A bitmap Img that stores indexes into a color table is called a palette-indexed bitmap. Some bitmap Img files have no need for a color table. For example, if a bitmap Img uses 24 bits per pixel, that bitmap Img can store the colors themselves rather than indexes into a color table. The following illustration shows a bitmap that stores colors directly (24 bits per pixel) rather than using a color table. The illustration also shows an enlarged view of the corresponding image. In the bitmap Img, FFFFFF represents white, FF0000 represents red, 00FF00 represents green, and 0000FF represents blue.

Acrobat to Img Converter is able to convert Adobe Acrobat PDF files to Bitmap Img format, the conversion can be done quickly and without any delay. Acrobat to Img Converter will render all elements from PDF file to raster image, you can view the output img files in any Image Viewer application. Acrobat to Img Converter does support password protected PDF files, you needn't include the password by manual if your PDF file is contain owner password only. Acrobat to Img Converter doesn't require the Adobe Acrobat and Adobe Reader installed, it is a stand-alone application.

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