; SEQ.PRO
;
; Originally written to show images from Polar Camera initial field test
; at Ryning Farm Observatory
; Modified 1993/1/29 by DPS to handle images from image tree structure
; on /jasper/cnsr3_data1
; Modified 1993/5/11 from SHOW.PRO to display images from both cameras
; in the order they were acquired.
;
; create byte-valued input parameters
cam=0B & filt=cam & day=cam & month=cam
mask=BYTARR(256,256)
; load various string-valued arrays needed
initialize,filters,months,days,modes,mpaths,firstchars
s=''
!ORDER=1
; set colour table 
loadct,13
; uncover screen where text is to be printed
IF !D.NAME EQ 'X' THEN WDELETE,0 

; prompt user and get input
PRINT,'Enter the starting year, month, day, UT hour, minute, and second desired'
READ,year,month,day,hr,min,sec
; ensure a 4-digit year for display; make reasonable assumptions
IF year LT 1900 THEN BEGIN
    IF year LT 50 THEN year=year+2000
    IF year GT 50 THEN year=year+1900
ENDIF

; create title for image plot
wtitle=STRING(year,months(month-1),day $
	     ,FORMAT='("Polar Camera",2X,I4,1X,A3,1X,I0.2)')
; define mask for images, with fixed horizon at 150 superpixels 
prad=150
d256=SHIFT(dist(256),128,128) & base=WHERE(d256 GT 150)
wprad=WHERE(d256 LE prad) & mask(wprad)=1

; make lists of available files of desired type
rdilist,0,year,month,day,hr,min,sec,n0,t0,files0
rdilist,1,year,month,day,hr,min,sec,n1,t1,files1
; zip lists together
IF (n0 EQ n1) THEN BEGIN	; equal numbers in both lists
    IF (MIN(ABS(t0-t1)) LT .5) THEN BEGIN
        t=TRANSPOSE([TRANSPOSE(t0),TRANSPOSE(t1)])
        files=TRANSPOSE([TRANSPOSE(files0),TRANSPOSE(files1)])
    ENDIF
ENDIF ELSE BEGIN		; lists have different lengths
    t=FLTARR(MAX([n0,n1]),2)
    files=STRARR(MAX([n0,n1]),2)
    IF n0 GT n1 THEN BEGIN	; more from Camera 0
        t(*,0)=t0
        files(*,0)=files0
        FOR i=0,n1-1 DO BEGIN	; find best match for each Cam 1 image
            d=MIN(ABS(t0-t1(i)),p)
            IF d LT 0.5 THEN BEGIN
                t(p,1)=t1(i)
                files(p,1)=files1(i)
            ENDIF
        ENDFOR
    ENDIF ELSE BEGIN		; more from Cam 1
        t(*,1)=t1
        files(*,1)=files1
        FOR i=0,n0-1 DO BEGIN   ; find best match for each Cam 0 image
            d=MIN(ABS(t1-t0(i)),p)
            IF d LT 0.5 THEN BEGIN
                t(p,0)=t0(i)
                files(p,0)=files0(i)
            ENDIF
        ENDFOR
    ENDELSE
ENDELSE
ext_list=extension(files)

; read in or generate required dark frames
dkt=0
dkim=INTARR(1,512)
dkpair=INTARR(256,512)
FOR i=0,n0-1 DO BEGIN
    exp0=FIX(STRMID(files0(i),STRLEN(files0(i))-7,3))
    we=WHERE(exp0 EQ dkt,nwe)
    IF nwe EQ 0 THEN BEGIN	; haven't got this exposure time yet
        rdmeandk,0,exp0,dk0
        rdmeandk,1,exp0,dk1
        dkpair(*,0:255)=dk0
        dkpair(*,256:511)=dk1
        dkt=[dkt,exp0]
        dkim=[dkim,dkpair]
    ENDIF
ENDFOR
FOR i=0,n1-1 DO BEGIN
    exp1=FIX(STRMID(files1(i),STRLEN(files1(i))-7,3))
    we=WHERE(exp1 EQ dkt,nwe)
    IF nwe EQ 0 THEN BEGIN	; haven't got this exposure time yet
        rdmeandk,0,exp1,dk0
        rdmeandk,1,exp1,dk1
        dkpair(*,0:255)=dk0
        dkpair(*,256:511)=dk1
        dkt=[dkt,exp1]
        dkim=[dkim,dkpair]
    ENDIF
ENDFOR
dkt=dkt(1:*)		; drop dummy entry at start of array
dkim=dkim(1:*,*)	; drop dummy column ...

; create and label image display window
X_charheight=10		; try to keep scalings that apply in X windows
X_charwidth=8
barwidth=16
ninrow=4
nincol=3
ninwin=ninrow*nincol
wwidth=ninrow*256+barwidth
wheight=nincol*256+4*X_charheight
IF !D.NAME EQ 'X' THEN $
    WINDOW,0,XSIZE=wwidth,YSIZE=wheight $
    ELSE DEVICE,/COLOR,BITS_PER_PIXEL=8	; PostScript
csz=((1.*X_charheight)/wheight)/((1.*!D.Y_CH_SIZE)/!D.Y_VSIZE)	; keep 'X' char size
XYOUTS,scl(res=120.,(wwidth-barwidth)/2) $
      ,scl(res=120.,wheight-3*X_charheight),wtitle $
      ,/DEVICE,ALIGNMENT=0.5,CHARSIZE=2.0*csz,WIDTH=twidthn
twidthd=CONVERT_COORD([twidthn,0.],/NORMAL,/TO_DEVICE)
twidthd=twidthd(0)			; we only need the x-component
; get user's name and display it
SPAWN,'whoami',username
XYOUTS,scl(res=120.,wwidth-X_charwidth),scl(res=120.,wheight-3.9*X_charheight) $
      ,'User '+STRUPCASE(username),ALIGNMENT=1.0,/DEVICE,CHARSIZE=csz
; get date/time and display them
SPAWN,'date -u',datetime
XYOUTS,scl(res=120.,wwidth-X_charwidth),scl(res=120.,wheight-2.5*X_charheight) $
      ,STRMID(datetime,11,9)+' UT',ALIGNMENT=1.0,/DEVICE,CHARSIZE=csz
XYOUTS,scl(res=120.,wwidth-X_charwidth),scl(res=120.,wheight-1.1*X_charheight) $
      ,STRMID(datetime,4,7)+STRMID(datetime,24,4),ALIGNMENT=1.0,/DEVICE,CHARSIZE=csz
; create and display color bar
bar=REBIN(BINDGEN(256,barwidth),nincol*256,barwidth)
bar=ROTATE(bar,3)
mtv,bar,ninrow*256,0,res=120.

; read in each image, decode the header, subtract dark frame, rebin to 
; 256x256 if necessary, scale to 8 bits and display
ip=-1
mid=-1
itime=BYTARR(4)
FOR i=0,MIN([n0,n1])-1 DO BEGIN
    ti=t(i,0)
    p=WHERE(ABS(t(*,1)-ti),nm)
    IF nm GT -1 THEN p=[i,p(0)] ELSE p=[i,i]
    FOR j=0,1 DO BEGIN
        fnlen=STRLEN(files(i,j))
        IF fnlen GT 0 THEN BEGIN
            rdkimg,files(i,j),h,im
            KIh=gethd(h)
            FOR k=0,3 DO itime(k)=KIh.misc.tm.(k)
; if image isn't 256x256, rebin it
            im=REBIN(im,256,256)
; ensure counts are actually summed if a 512x512 image is compressed
            cfac=512/(256*KIh.exp.sbin)
            rfac=512/(256*KIh.exp.pbin)
            im=im*cfac*rfac
; subtract appropriate dark frame
            exp=FIX(KIh.misc.exp_scale*KIh.exp.exposure/1000.)
            dp=WHERE(dkt EQ exp)
            im=(im-dkim(256*dp(0):256*dp(0)+255,256*j:256*j+255))>0
; identify useful min and max values for byte-scaling
            ih=HISTOGRAM(im(wprad),MIN=0,BIN=1)	; histogram of exposed image
            cih=ih	; next line computes cumulative pixel value pdf
            FOR jj=1,N_ELEMENTS(cih)-1 DO cih(jj)=cih(jj)+cih(jj-1)
            cih=cih/FLOAT(MAX(cih))		; normalize to unity
            lmaxi=MAX(WHERE(cih LE .999))	; top 0.1% of pixels saturate
; if viewing sky image, take dark 'skirt' as min value
            exptype=STRMID(files(i,j),fnlen-12,1)
            shut=(exptype EQ 'b') OR (exptype EQ 'd')	; bias or dark frame
            IF NOT shut THEN BEGIN
                bh=HISTOGRAM(im(base),MIN=0,BIN=1)
                maxbh=MAX(bh,lmaxbh)		; bottom = most prob. skirt value
            ENDIF ELSE BEGIN
; otherwise take lowest level in dark frame
                lmini=MIN(WHERE(cih GE .001))
                lmaxbh=lmini	; rename this parameter for compatibility below
            ENDELSE
        ENDIF ELSE BEGIN
; if no file name, generate an identifiably fake image
            im=BYTARR(256,256)
            im(RANDOMU(s,100))=1
            itime=BYTARR(4)
            exp=-1
            lmaxi=1
            lmaxbh=0
        ENDELSE

        ip=ip+1		; index number for screen position of image
; show image orientation, one time only
        IF ip EQ 0 THEN BEGIN
            nflag=isnumber(KIh.misc.az,azimuth)
            IF nflag NE 0 THEN BEGIN 	; if the camera azimuth is known,
                azrad=!DTOR*azimuth		; plot arrows showing the azimuth
                leftend=scl(res=120.,wwidth/2.)-twidthd/2.
                maxlen=(leftend-scl(res=120.,1.5*X_charwidth)) $
                       /scl(res=120.,(COS(azrad)+SIN(azrad))*X_charheight)
                arlen=MIN([FIX(maxlen),4])*X_charheight
                tailx=REPLICATE(scl(res=120.,0.5*X_charwidth+SIN(azrad)*arlen),2)
                taily=REPLICATE(scl(res=120.,nincol*256),2)
                headx=[tailx(0)-scl(res=120.,arlen*SIN(azrad)), $
                       tailx(1)+scl(res=120.,arlen*COS(azrad))]
                heady=[scl(res=120.,nincol*256+arlen*COS(azrad)), $
                       scl(res=120.,nincol*256+arlen*SIN(azrad))]
                arrow,tailx,taily,headx,heady,/device,hsize=-0.2
                XYOUTS,tailx(0),heady(0)-scl(res=120.,X_charheight),'N' $
                       ,ALIGNMENT=0,/DEVICE,CHARSIZE=csz
                XYOUTS,headx(1)+scl(res=120.,X_charwidth),heady(1),'E' $
                       ,ALIGNMENT=0.5,/DEVICE,CHARSIZE=csz
            ENDIF ELSE BEGIN		; otherwise show cardinal directions
                XYOUTS,scl(3*X_charwidth,res=120.) $
                      ,scl(nincol*256+3*X_charheight,res=120.) $
                      ,'N',/DEVICE,ALIGNMENT=0.5,CHARSIZE=csz
                XYOUTS,scl(res=120.,X_charwidth) $
                      ,scl(res=120.,nincol*256+1.5*X_charheight),'W' $
                      ,/DEVICE,ALIGNMENT=0.5,CHARSIZE=csz
                XYOUTS,scl(res=120.,5*X_charwidth) $
                      ,scl(res=120.,nincol*256+1.5*X_charheight),'E' $
                      ,/DEVICE,ALIGNMENT=0.5,CHARSIZE=csz
                XYOUTS,scl(res=120.,3*X_charwidth) $
                      ,scl(res=120.,nincol*256),'S',/DEVICE $
                      ,ALIGNMENT=0.5,CHARSIZE=csz
            ENDELSE
        ENDIF
; display the image
        mtv,ROTATE(im*mask,5),low=lmaxbh,high=lmaxi,res=120. $
           ,(ip MOD ninrow)*256,(nincol-1-(ip MOD ninwin)/ninrow)*256
; display image camera, filter, and sequence numbers
        IF fnlen GT 0 $
            THEN camfilt=STRMID(files(i,j),fnlen-9,2) $
            ELSE camfilt=STRMID(files(i,1-j),fnlen-9,2)
        XYOUTS,scl(res=120.,(ip MOD ninrow)*256+1) $
              ,scl(res=120.,(nincol-(ip MOD ninwin)/ninrow)*256-1-X_charheight) $
              ,camfilt+':'+ext_list(i),/DEVICE,ALIGNMENT=0.0,CHARSIZE=csz $
              ,COLOR=0.8*!D.N_COLORS
; and image time
        XYOUTS,scl(res=120.,(ip MOD ninrow)*256+1) $
              ,scl(res=120.,(nincol-1-(ip MOD ninwin)/ninrow)*256+3+X_charheight) $
              ,/DEVICE,ALIGNMENT=0.0,CHARSIZE=csz,COLOR=0.8*!D.N_COLORS $
              ,STRING(itime(0:2),FORMAT='(I2.2,":",I2.2,":",I2.2)')
; and exposure time
        XYOUTS,scl(res=120.,(ip MOD ninrow)*256+1) $
              ,scl(res=120.,(nincol-1-(ip MOD ninwin)/ninrow)*256+1) $
              ,STRING(exp,FORMAT='(F5.1,1X,"s")'),/DEVICE,ALIGNMENT=0.0 $
              ,CHARSIZE=csz,COLOR=0.8*!D.N_COLORS
; and maximum displayed DN
        XYOUTS,scl(res=120.,((ip MOD ninrow)+1)*256-1) $
              ,scl(res=120.,(nincol-(ip MOD ninwin)/ninrow)*256-1-X_charheight) $
              ,STRING(FIX(lmaxi),FORMAT='("< ",I0.0," DN")') $
              ,/DEVICE,ALIGNMENT=1.0,CHARSIZE=csz,COLOR=0.8*!D.N_COLORS
; and minimum displayed DN
        XYOUTS,scl(res=120.,((ip MOD ninrow)+1)*256-1) $
              ,scl(res=120.,(nincol-1-(ip MOD ninwin)/ninrow)*256+1) $
              ,STRING(FIX(lmaxbh),FORMAT='("> ",I0.0," DN")'),/DEVICE $
              ,ALIGNMENT=1.0,CHARSIZE=csz,COLOR=0.8*!D.N_COLORS
        PRINT,'.',FORMAT='(A,$)'
        IF (ip+1) MOD ninwin EQ 0 THEN PRINT,'|',FORMAT='(A,$)'
    ENDFOR
    IF GET_KBRD(1) EQ 'q' THEN GOTO,DONE
ENDFOR
DONE:
PRINT,''
END