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PPM file format
Portable pixmap images can be stored using the PPM format, which is basic, for example, color (PPM), grayscale (PGM), and black and white (PBM). A portable pixmap can provide a hallway representation of information in the conversion process of bitmap image files of the three types mentioned between different platforms. Jeff Poskanzerom developed the PPM format.
PPM files comprise sequences of a single or more PPM image. Data, padding, and limits do not exist before or after or in the middle of images. Every PPM comprises a single magic number used in identifying the type of file; the magic number for a PPM image is the two-character P6, whitespace (blanks, TABs, CRs, and LFs), and width presented as ASCII characters in decimal. It also comprises whitespace again, which is shown in ASCII decimal. Whitespace, the color value at a maximum (Maxval), is in decimal form, and it should be greater than zero but less than 65536. It is also composed of another single whitespace character, which is on another line. Lastly, it is composed of a raster of height rows found in reverse chronological order. The rows are comprised of width pixels in a left to right format. The samples represented have a pure binary nature, which is by one or two bytes. I byte has a Maxval of less than 256; otherwise, it is 2 bytes. The first byte is the most relevant. The straightforward format is another version of the PPM that exists but is most uncommon.