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NAME: average_cut PURPOSE: average a map along a given direction. CATEGORY: image processing CALLING SEQUENCE: cut=average_cut(d,h,angle=angle,Ninter=Ninter,dist=dist,xval=xval, $ silent=silent,dval=dval,input_distance=input_distance, $ median=median,std=std INPUTS: d,h = data array (2D) and fits header OPTIONAL INPUT PARAMETERS: Ninter = number of intervals for the integration along the cut (default=100) angle = angle of the cut (degree) from North (default=1st diagonal) input_distance = a (2D) array of distance to be used in the averaging silent = if set, behave silently. median = if set, the median value is used instead of the average. OUTPUTS: cut = values averaged along the cut (1D) size given by Ninter OPTIONAL OUTPUT PARAMETERS: xval = average (or median) position values (1D) along the cut (degrees). dval = position values (1D) used to average into (degrees). same as xval if no !indef values are excluded. dist = distance array used in the averaging. std = standard deviation values (1-sig) COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: PROCEDURE: !indef values in the image (or distance array, if input_distance is used) are excluded from the processing. Uses sxpar.pro, la_median.pro, la_mean.pro MODIFICATION HISTORY: 20-Aug-1998, Written by Jean-Philippe Bernard
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:average_cut.pro)
NAME: cut_image CALLING SEQUENCE: imout=cut_image(im,hin[,hout=hout][,/silent]) PURPOSE: cut a fits image to trim undefined lines and columns INPUTS: im,hin = image (2D) and header OPTIONAL INPUT: silent : If set, behaves silently OUTPUTS: imout = trimmed image OPTIONAL OUTPUTS: hout = header for imout PROCEDURE AND SUBROUTINE USED Straightforward Uses sxpar.pro find_ind.pro RESTRICTIONS MODIFICATION HISTORY: written JPB 15-08-92
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:cut_image.pro)
NAME: degrade_res PURPOSE: degrade the angular resolution of an image by convolving it with a 2D gaussian. indef values in the original image are not considered if remove_border is set, values affected by the map edge (closer than reso from the edge) are set to indef CATEGORY: image_processing CALLING SEQUENCE: result=degrade_res(input,h,reso,hout [,/remove_border][,/remove_indef][,indef=] [,get_kernel=][,/no_convol]) INPUTS: input,h = input image (2D or 3D) and header reso = angular resolution requiered (degree) hout = output header OPTIONAL INPUTS: remove_border = if set the edge of the map is set to indef remove_indef = if set the edge of indef zones is set to indef indef = specify indef value to be used [default=!indef] no_convol = if set no convolution is performed KEYWORD PARAMETERS: OUTPUTS: result of the function = smoothed image OPTIONAL OUTPUTS: get_kernel = if set, the kernel is returned COMMON BLOCKS: None SIDE EFFECTS: The final image does not really have the resolution reso ! RESTRICTIONS: PROCEDURE: EXAMPLE: MODIFICATION HISTORY: written JPB 09-08-92
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:degrade_res.pro)
NAME: enlarge CALLING SEQUENCE: ind2=enlarge(ind,Npix,sx,sy) PURPOSE: enlarge a region pointed by ind in a 2D array by Npix pixels the area selected is enlarged by neighbor pixels INPUTS: ind = index of the region Npix = number of pixels to extend sx, sy = size of the array in x and y OPTIONAL INPUT: OUTPUTS: modified index SUBROUTINE AND PROCEDURE USED SIDE EFFECTS: Should use long loop index, instead of cutting loops. MODIFICATION HISTORY: WRITTEN, J.P. Bernard, 6-11-1992 modified JPB Jun 21 1994 to deal with large indexes sets
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:enlarge.pro)
NAME: fix_radec_header PURPOSE: makes sure that the center of a header is not at center of a pixel useful for TAN projection headers for which coordinates cannot compute at center CATEGORY: Coordinates conversions CALLING SEQUENCE: header=fix_radec_header(h) INPUTS: h = the input header OPTIONAL INPUT PARAMETERS: OUTPUTS: header = modified header OPTIONAL OUTPUT PARAMETERS: ACCEPTED KEY-WORDS: COMMON BLOCKS: SIDE EFFECTS: RESTRICTIONS: applied only to RA-TAN headers. PROCEDURE: MODIFICATION HISTORY: Written Jan 31 1995 J.P. Bernard, IPAC.
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:fix_radec_header.pro)
NAME: integrated_intensity PURPOSE: compute integrated intensity map in a given vlsr range CATEGORY: Molecular data reduction CALLING SEQUENCE: ii=integrated_intensity(input,header,[vrange=]) INPUTS: d = data cube h = data header OPTIONAL INPUT PARAMETERS: vrange = vlsr range to be used (default=full range) OUTPUTS: ii = ntegrated intensity map OPTIONAL OUTPUT PARAMETERS: None ACCEPTED KEY-WORDS: silent = if set, behaves silently COMMON BLOCKS: Npne SIDE EFFECTS: does not work with default vrange RESTRICTIONS: PROCEDURE: make_axis.pro EXAMPLES MODIFICATION HISTORY: Written by J.P. Bernard Sep 1 1998
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:integrated_intensity.pro)
NAME: make_axis CALLING SEQUENCE: make_axis,header,axis1,[axis2[,axis3]] PURPOSE: make 1D axis INPUTS: header = cube or image header OPTIONAL INPUT: ACCEPTED KEY-WORDS: OUTPUTS: axis1, axis2, axis3 PROCEDURE AND SUBROUTINE USED SIDE EFFECTS: ? MODIFICATION HISTORY: written Jean-Philippe Bernard 19-Mars-93
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:make_axis.pro)
NAME: make_pos_vel_map PURPOSE: Construct a position-velocity diagram from a cube of molecular data from a center position along a given direction on the sky. CATEGORY: image processing CALLING SEQUENCE: map=make_pos_vel_map(d,h,vrange,vstep,Ninter,angle,dl, $ cent_coord=cent_coord,vval=vval,xval=xval, $ xrange=xrange,dist=dist) INPUTS: d,h = data array (3D) and fits header vrange = range of vlsr to be covered by map vstep = step in vlsr of the map Ninter = number of intervals for the integration along the cut and the y-size of map angle = angle of the cut (degree) from North dl = width of the cut (degree) OPTIONAL INPUT PARAMETERS: cent_coord = coordinates (degree) from the center (e.g. [ra,dec]) default=center of the cube xrange = range of position values for map. default=all values silent = if set behaves silently OUTPUTS: map = position-velocity map. x and y axis correspond to velocity and position respectively. OPTIONAL OUTPUT PARAMETERS: vval = vlsr values (1D) corresponding to map xval = position values (1D) corresponding to map dist = distance array used in the averaging. stdmap = standard deviation map (1-sig) COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: PROCEDURE: Uses average_cut.pro, integrated_intensity.pro MODIFICATION HISTORY: 20-Aug-1998, Written by Jean-Philippe Bernard
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:make_pos_vel_map.pro)
NAME: mosaique3 CALLING SEQUENCE: mosaique3,al,del,d,h,w,res,weight PURPOSE: create a composite image of image res (big image) and image in d (small image). Coordinates are derived from their headers and projected coreclty res might already have defined values, in which case (res+d)/2. is set in the overlaping regions interpolation is done bilinearily (no averaging in a beam) INPUTS: al,del = alpha & delta coord of each pix of big image (res). 2 D arrays d,h = data and header of the small image w = weight of the image d weight = current weight map for res (used as a weight in summing) OPTIONAL INPUT: undef = undefined value silent = if set routine is silent deg_res = if set the small image's angular resolution is first degraded to deg_res (deg) OUTPUTS: res = res+small image, weight is updated PROCEDURE AND SUBROUTINE USED 1/ input coordinates are transformed into pixels of the small image input coordinates are considered to be of the type given in h (accepted are RA, GLON, ECLON) 2/ If requested, the angular resolution of the small image is first degraded using degrade_res.pro 3/ The small image is projected onto the big one using my_bilinear2 4/ The so-projected image is added to res res might already have defined values, in which case (res+d)/2. is set in the overlaping regions interpolation is done bilinearily (no averaging in a beam) my_bilinear2,sxpar,degrade_res RESTRICTIONS when adding the 1st map, res should be all set to !indef and weight to 0. MODIFICATION HISTORY: written JPB 15-08-92 modified JPB Aug 23 1996 to include indiv weight w
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:mosaique3.pro)
NAME: my_bilinear2 PURPOSE: same as bilinear of user library but can deal with big arrays CATEGORY: Coordinates conversions CALLING SEQUENCE: my_bilinear , array, x, y INPUTS: array = array (2D) in which interpolation is to be made x, y = 2D array of x and y values (must be of same size) OPTIONAL INPUT PARAMETERS: OUTPUTS: function output=interpolated array (same size as x and y) OPTIONAL OUTPUT PARAMETERS: COMMON BLOCKS: SIDE EFFECTS: x and y values not in the target image (outside array) are changed to 0 or -1 RESTRICTIONS: PROCEDURE: BILINEAR (users library) indef values are difficult to handle. Here values in the interpolated values which values are smaller than the smaller defined value in the original array are set to indef. This works for a highly <0 indef (e.g indef=-32768.) and generally >0 image MODIFICATION HISTORY: 14-Aug-1992, Written by Jean-Philippe Bernard, Nagoya Univ.
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:my_bilinear2.pro)
NAME: project2 CALLING SEQUENCE: im2=project2(h1,im1,h2) PURPOSE: reprojects im1,h1 into the projection specified by h2 INPUTS: im1,h1 = image, header to be reprojected h2 = header of the output image (must have a different proj as h1) OPTIONAL INPUT: save_it=to save the project parameters restore_it=to restore project parameters previous_lut=to use the previous projection OUTPUTS: im2 = result of the reprojection SUBROUTINE AND PROCEDURE USED sxpar,create_coo2,coo2pix2,my_bilinear, coo2coo SIDE EFFECTS: RESTRICTIONS: Should take coord,epoch,Naxis,.... into account. MODIFICATION HISTORY: written J.P. Bernard @ IPAC Jan 31 1995
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:project2.pro)
NAME: rebin_image PURPOSE: scales a fits image by a given scale factor and update header info. CATEGORY: image_processing CALLING SEQUENCE: im=rebin_image(image,header,hout,ffact[,/sample][,/median]) INPUTS: image = input image (2D) header = header for image ffact = rebin factor OPTIONAL INPUTS: sample = to keep pixel information median = ? KEYWORD PARAMETERS: OUTPUTS: hout = modified header (for im) im = rebined image OPTIONAL OUTPUTS: COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: PROCEDURE: EXAMPLE: MODIFICATION HISTORY: written JPB 09-08-92
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:rebin_image.pro)
NAME: set_dist2 CALLING SEQUENCE: set_dist2,sep,i0,j0,k0 PURPOSE: Computes the square distance array to a center in pixels INPUTS: sep = empty array i0 = center position on 1st axis j0 = center position on 2nd axis OPTIONAL INPUT: k0 = center position on 3rd axis OUTPUTS: sep = array containing the square distance in pixels PROCEDURE AND SUBROUTINE USED SIDE EFFECTS: EXAMPLE: MODIFICATION HISTORY: written by Jean-Philippe Bernard (?) 09-92
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:set_dist2.pro)
NAME: zmy CALLING SEQUENCE: zmarray=zmy(image,head,siz[,hout] [,centcoord=[]][,centpix=[]][,/previous_lut) PURPOSE: zoom an image in various coordinate system/projection. A new header is generated for the zoomed array INPUTS: image, head = original image and header siz = size of the area (degrees). Can be a 2 elt set OPTIONAL INPUT: centcoord = a set giving center coord in degrees in the NEW coordinate system centpix = a set giving center pixel in the original image new_proj = to set a new projection type new_coord = to set a new coordinate system previous_lut = use the previous Look-up table projection OUTPUTS: hout = header of the zoomed image PROCEDURE AND SUBROUTINE USED A zoomed image header is produced, according to the coordinates, coordinate system and projection specified. The result image is obtained as the projection of the input corresponding to this new header. pix2coo2,coo2pix2,h2pix,project2 COMMONS: @proj_common.com, @lut_proj.com SIDE EFFECTS: ? MODIFICATION HISTORY: written JPB 05-08-92 Modified JPB 22-01-93 to use convert_ad_pix instead of cor2pix and create a better output header Modified 19-Mar-93 to put header center @ image center Modified Dec 12 1993 to allow deal with l,b maps and cube inputs Modified MAR 22 1995 to Generalize coordinate conversion
(See MacintoshHD:IDL Libraries:JPBlib:Image_Processing:zmy.pro)