PROJECT:
	SXI-M Ground Data System

 NAME:
	MAKE_BKGD

 PURPOSE:
	Process level-1 backgrounds for subtraction.

 EXPLANATION:
	TBS

 CALLING SEQUENCE:
   function make_bkgd,dark_path,index1,background

 INPUTS:
	dark_path		=	directory where background files are located
	index1			=	FITS level-1 header index for solar image
						(contains names of two background files)

 OUTPUTS:
	background		=	512x512 background array

 OPTIONAL INPUT KEYWORDS:
	N/A

 EXTERNAL CALLS:
   N/A

 CALLED BY:
	SXIM_PREP

 METHOD:
	TBS

 CALLS: ***
	READFITS [1], READFITS [2], READFITS [3], fitshead2struct, sxi_make_name
	sxi_parse_name
 HISTORY:
   003.000 Written by Steven Hill at NOAA/SEC 29 Oct 2001

 PROJECT:
	SXI-M Ground Data System

 NAME:
	MAKE_BROWSE

 PURPOSE:
   Generate byte images for browsing and real-time display.

 EXPLANATION:
	TBS

 CALLING SEQUENCE:
	MAKE_BROWSE,image,index,image_type,level,browse,stamp

 INPUTS:
	image			=	input image (512x512)
	index			=	input header (from FITS) as index structure
   image_type		=	image type, e.g., flare, etc.
	level			=	image level code, e.g., A=level-0, B=level-1

 OUTPUTS:
	browse			=	browse image array with annotation (512x512 byte array)
	stamp			=	stamp image array with no annotation (128x128 byte array)

 OPTIONAL INPUT KEYWORDS:
	N/A

 EXTERNAL CALLS:
	N/A

 CALLED BY:
	SXIG12_PREP

 METHOD:
	TBS

 CALLS: ***
	SXI_MAKE_BROWSE, str_replace [1], str_replace [2]
 CALLED BY:
	REDUCE_LEVEL_05
 HISTORY:
   001.001  Written by Steven Hill at NOAA/SEC 30 Jan 2001
   001.002  Modified by SMH 4/6/2001
            Removed full path for level-1 circular mask file
            Added color bar on left side of full sized images
   001.003  Modified by SMH 7/10/2001
            Added correct ph/pix/sec scaling for level-1 PNGs
   001.004  Modified by SMH 7/26/2001
            Accommodated message for missing TSYNC packet
            impact on MCP gain computation
   003.001  Modified by VJP 8/13/2001
            changed mask read to byte array
            changed mask test so that mask only applied for 'SUN' images
   003.002  Modified by SMH 9/10/2001
            Made display scales fixed at 0-1023 for level-0 and
            0 to the maximum possible for level-1 images
            Changed MCP and exposure time to settings instead of
            measured actuals.
   003.003  Modified by SMH 9/19/2001
            Set maximum for level-1 files based on MCP gain setting
            and an offset value to get around measurement noise on
            MCP1K_V telemetry
   003.004  Modified by SMH 9/20/2001
            Added incremental scaling so that underexposed images
            could be seen
   003.005  Modified by SMH 9/21/2001
            Scale level-1 images based on MCP_GAIN rather than MCP1K_V info
            in BSCALE.  Noise in MCP1K_V measurement makes images flicker.
            Need a long-term solution to this.
   003.006  Modified by SMH 9/21/2001
            Added logic to exclude WAVELNTH='RDSH' images from level-1 scaling.
            Previously had been screening on IMAGE_TYPE='BG', but for new
            ESTs that is sometimes 'TST' instead.
   003.007  Modified by SMH 9/24/2001
            Commented out incremental scaling from 003.004 and replaced with
            fixed base 10 logarithmic scaling.
   003.008  Modified by SMH 10/3/2001
            Fixed date-time parsing error for month
   003.009  Modified by SMH 10/29/2001
            Moved dn-to-photons conversion to independent function
   003.010  Modified by SMH 11/19/2001
            Changed Level-1 scaling from ph/s to DN/s due to uncertainty
            in MCP gain linearity
   003.011  Modified by SMH 05/17/2002
            Changed name to sxi_make_browse from make_browse
            Changed call to sxim_dn2photons to sxig12_dn2photons
   003.012  Modified by SMH 6/11/2002
            Added notation to browse image to indicate images taken
            with logarithmic amplifier
            Removed MCP error message, removed msg as a passed parameter.
            Error displays will now be based on index paramaters
   003.013  Modified by SMH 6/12/2002
            Changed date-time format in browse images to be more
            consistent with SQL and CCSDS formats
   003.014  Modified by SMH 4/22/2003
            Changed MAXSCALE to SCALE_FACTOR which is based only on
            DN/s rather than fudging a DN2PH of unity to retain future
            options with physical units. For level-1 products, set
            SCALE_FACTOR=4.0 to minimize monitor saturation when
            instrument saturated pixels have been replaced.
            Set IMGSCALE to unity.
            Added character 'C' to PNG annotation when sat. pix.
            are replaced to indicated 'composite' image