Lossless Compression Handbook

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PART IV / STANDARDS

either 5 or 120 combinations of compression parameters are tried, usually manages no more than

1% improvement over the standard PNG heuristic. 13

19.9 MNG

MNG, short for

Multiple-Image Network Graphics,

was originally conceived as a minimal

metaformat for gluing together sequences of PNG images. But because there was no pressing

need for a multi-image or animated PNG extension in early 1995, its development was left on hold

for more than a year, allowing developers time instead to write the first PNG implementations

and to begin the long process of standardization.

In the meantime, as we noted earlier, ...