Quo Vadis JPEG - Another update (3)

[Thomas Richter]

Hi folks, just released a new version of the experimental(!) jpeg coder
demonstrating the ideas our new JPEG standard will provide. The sources
are here:

https://github.com/thorfdbg/libjpeg

Only minor modifications were made in this release. The Huffman coder
now fills undefined bits at the end of the entropy coded segment by
ones, and potentially inserts a stuffed zero byte. Note that the
standard defines this only in an informative note, so it is likely not
required. The insertion of a stuffed zero byte at this position might
also be unnecessary as a parser should identify the first 0xff byte
ahead of the marker as "fill byte".

Residual coding has been reworked and uses now a simple progressive scan
with the special DC case removed. The performance does not differ
significantly, and it makes integration into legacy software or hardware
easier.

Default Huffman tables are now also provided for progressive and
lossless scans, thus optimizing the Huffman tables just for these scan
types is no longer necessary. Residual or refinement scans still require
this argument, though.

Usage of the codec does not differ from previous releases, though
codestreams using the residual coding mode are not compatible to those
generated by 0.5.
Note that this is still experimental software and the codestream might
still change until the ISO committee decides on the technology.

Finally, a couple of workarounds for earlier releases of the g++
compiler have been added.

Greetings,
Thomas