MIL-HDBK-1300 National Imagery Transmission Format Standard NitfsThis document describes the NITFS and its image and communications processing components. It provides general information regarding NITFS.

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MIL-HDBK-1300A

5.5.1.4  Vector Quantization.  Vector quantization is a compression method that is suitable for gray scale and color images of any pixel depth.  Compression is very slow and computationally intensive.  For this reason, it is not normally used for the distribution of near real time data.  However, decompression without special hardware is very fast (as little as one-tenth the time of JPEG), so it is often used for static data, such as maps or broad area imagery.  Image quality is good at moderate compression ratios.  Vector Quantization compression is defined in more detail in MIL-STD-188-199.

FIGURE 8.  General JPEG DCT-based encoder.

FIGURE 9.  General JPEG DCT based decoder.

5.5.1.5  None.  No compression is used when the user desires to send the imagery at full resolution with no quality loss.  The image data are blocked left to right, top to bottom, according to the values supplied in the image subheader.

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