2007-07-26  Raphael Quinet  <raphael@gimp.org>

	* plug-ins/jpeg/Makefile.am
	* plug-ins/jpeg/jpeg-quality.[ch]
	* plug-ins/jpeg/jpeg-settings.[ch]: new files including functions
	for detecting the quality setting of existing JPEG files by
	analyzing their quantization tables, functions for storing this
	quality and other JPEG settings in a parasite, and functions for
	restoring these values.

	* plug-ins/jpeg/jpeg-load.c (load_image): save the original JPEG
	settings in a parasite after reading the JPEG header.

	* plug-ins/jpeg/jpeg.c (run): restore the original JPEG settings
	if they had been attached to a parasite and if they are better
	than the defaults.

	* plug-ins/jpeg/jpeg-save.c (save_image): added new type of
	subsampling 1x2,1x1,1x1, which is useful for images with height >
	width such as rotated images from some cameras.
	(save_dialog): added hints about how the subsampling types can be
	used, marked these strings as translatable.

	* plug-ins/jpeg/jpegqual.c: new utility to report the quality
	settings and sampling factors of existing JPEG files.

svn path=/trunk/; revision=23018