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			simple reversible color transform into the processing
			which significantly improves the compression.
			Use this switch in combination with the -block N
			switch (see above) for lossless JPEG coding.
			CAUTION: A decoder with inverse color transform
			support is required for this feature.  Reversible
			color transform support is not yet widely implemented,
			so many decoders will be unable to view a reversible
			color transformed JPEG file at all.

	-bgycc		Create big gamut YCC JPEG file.
			In this type of encoding the color difference
			components are quantized further by a factor of 2
			compared to the normal Cb/Cr values, thus creating
			space to allow larger color values with higher
			saturation than the normal gamut limits to be encoded.
			In order to compensate for the loss of color fidelity
			compared to a normal YCC encoded file, the color
			quantization tables can be adjusted accordingly.
			For example, cjpeg -bgycc -quality 80,90 will give
			similar results as cjpeg -quality 80.
			CAUTION: For correct decompression a decoder with big
			gamut YCC support (JFIF version 2) is required.
			An old decoder may or may not display a big gamut YCC
			encoded JPEG file, depending on JFIF version check
			and corresponding warning/error configuration.
			In case of a granted decompression the old decoder
			will display the image with half saturated colors.

	-dct int	Use integer DCT method (default).
	-dct fast	Use fast integer DCT (less accurate).
	-dct float	Use floating-point DCT method.
			The float method is very slightly more accurate than
			the int method, but is much slower unless your machine
			has very fast floating-point hardware.  Also note that
			results of the floating-point method may vary slightly
			across machines, while the integer methods should give
			the same results everywhere.  The fast integer method
			is much less accurate than the other two.

	-nosmooth	Don't use high-quality downsampling.

	-restart N	Emit a JPEG restart marker every N MCU rows, or every
			N MCU blocks if "B" is attached to the number.
			-restart 0 (the default) means no restart markers.

	-smooth N	Smooth the input image to eliminate dithering noise.
			N, ranging from 1 to 100, indicates the strength of
			smoothing.  0 (the default) means no smoothing.

	-maxmemory N	Set limit for amount of memory to use in processing
			large images.  Value is in thousands of bytes, or
			millions of bytes if "M" is attached to the number.
			For example, -max 4m selects 4000000 bytes.  If more
			space is needed, temporary files will be used.

	-verbose	Enable debug printout.  More -v's give more printout.
	or  -debug	Also, version information is printed at startup.

The -restart option inserts extra markers that allow a JPEG decoder to
resynchronize after a transmission error.  Without restart markers, any damage
to a compressed file will usually ruin the image from the point of the error
to the end of the image; with restart markers, the damage is usually confined
to the portion of the image up to the next restart marker.  Of course, the
restart markers occupy extra space.  We recommend -restart 1 for images that
will be transmitted across unreliable networks such as Usenet.

The -smooth option filters the input to eliminate fine-scale noise.  This is
often useful when converting dithered images to JPEG: a moderate smoothing
factor of 10 to 50 gets rid of dithering patterns in the input file, resulting
in a smaller JPEG file and a better-looking image.  Too large a smoothing
factor will visibly blur the image, however.

Switches for wizards:

	-baseline	Force baseline-compatible quantization tables to be
			generated.  This clamps quantization values to 8 bits
			even at low quality settings.  (This switch is poorly
			named, since it does not ensure that the output is
			actually baseline JPEG.  For example, you can use
			-baseline and -progressive together.)

	-qtables file	Use the quantization tables given in the specified
			text file.

	-qslots N[,...] Select which quantization table to use for each color
			component.

	-sample HxV[,...]  Set JPEG sampling factors for each color component.

	-scans file	Use the scan script given in the specified text file.

The "wizard" switches are intended for experimentation with JPEG.  If you
don't know what you are doing, DON'T USE THEM.  These switches are documented
further in the file wizard.txt.


DJPEG DETAILS

The basic command line switches for djpeg are:

	-colors N	Reduce image to at most N colors.  This reduces the
	or -quantize N	number of colors used in the output image, so that it
			can be displayed on a colormapped display or stored in
			a colormapped file format.  For example, if you have
			an 8-bit display, you'd need to reduce to 256 or fewer
			colors.  (-colors is the recommended name, -quantize
			is provided only for backwards compatibility.)

	-fast		Select recommended processing options for fast, low
			quality output.  (The default options are chosen for
			highest quality output.)  Currently, this is equivalent
			to "-dct fast -nosmooth -onepass -dither ordered".

	-grayscale	Force gray-scale output even if JPEG file is color.
			Useful for viewing on monochrome displays; also,
			djpeg runs noticeably faster in this mode.

	-scale M/N	Scale the output image by a factor M/N.  Currently
			supported scale factors are M/N with all M from 1 to
			16, where N is the source DCT size, which is 8 for