C	PROGRAM FILGAP.FT
C	----------------
C
C	PETER LEMKIN
C	IMAGE PROCESSING UNIT, DCBD
C	NATIONAL CANCER INSTITUTE
C	NATIONAL INSTITUTES OF HEALTH
C	9000 ROCKVILLE PIKE
C	BETHESDA, MD. 20014
C
C	FEB 6, 1978
C
C
C
C	INTRODUCTION
C	------------
C	FILGAP.FT IS A CHAINED PROGRAM USED WITH BMON2
C	IT RECEIVES ITS ARGUMENTS FROM THE CD AREA AND THE IBM1,IHGH1
C	IBM2,IHGH2, JBM, JHGH  VARIABLES IN COMMON. COMMON IS RESTORED
C	FIRST BEFORE THE FUNCTION (TO BE INSERTED INTO THE BODY) IS
C	EVALUATED. AFTER THE FUNCTION IS PERFORMED, COMMON
C	IS SAVED AND BMON2 IS CHAINED BACK TO.
C	ANY COMPUTATIONS ARE DONE, THE ARGUMENTS ARE THEN CHECKED
C
C	<BMj>_FILGAP,<BMi>,Threshold  t  -  Fill gaps in narrow
C        dark lines. The filter looks for a light gap of 1 to  2
C        pixels in length in a narrow dark line of 1 to 2 pixels
C        wide.  The filter consists of a 5x5 neighborhood  in  8
C        different   orientations   (actually   16   but  8  are
C        symmetric).
C	Let Fi be one of the eight filters. Then the Gj(x,y) is
C        computed as:
C
C	Gj(x,y) = If Max{Fi(x,y)} > t
C			Then Max(25-neighborhood of (x,y))
C			Else Gi(x,y);
C
C	The eight filters are:
C
C		0  0 +4  0  0
C		0  0 +2  0  0
C	a      -2 -1 -6 -1 -2
C		0  0 +2  0  0
C		0  0 +4  0  0
C
C		0  0 +2 +2  0
C	       -1  0 +1 +1  0
C	b      -1 -1 -6 -1 -1
C		0 +1 +1  0 -1
C		0 +2 +2  0  0
C
C	       -2  0  0  0 +4
C	        0 -1  0 +2  0
C	c       0  0 -6  0  0
C		0 +2  0 -1  0
C	       +4  0  0  0 -2
C
C	        0 +2 +2  0  0
C	        0 +1 +1  0 -1
C	d      -1 -1 -6 -1 -1
C	       -1  0 +1 +1  0
C	        0  0 +2 +2  0
C
C	The  filters a', b', c' and d' are filters a, b, c, and
C        d rotated 90 degrees.
C
C	        0  0 -2  0  0
C	        0  0 -1  0  0
C	a'     +4 +2 -6 +2 +4
C	        0  0 -1  0  0
C	        0  0 -2  0  0
C
C	        0  0 -1 -1  0
C	       +2 +1 -1  0  0
C	b'     +2 +1 -6 +1 +2
C	        0  0 -1 +1 +2
C	        0 -1 -1  0  0
C
C	       +4  0  0  0 -2
C	        0 +2  0 -1  0
C	c'      0  0 -6  0  0
C	        0 -1  0 +2  0
C	       -2  0  0  0 +4
C
C	        0 -1 -1  0  0
C	        0  0 -1 +1 +2
C	d'     +2 +1 -6 +1 +2
C	       +2 +1 -1  0  0
C	        0  0 -1 -1  0
C
C	The 5 line buffers are stored in Field 6.
C
C
C	OPDEFS
C	------
S	OPDEF	TADI	1400
S	OPDEF	DCAI	3400
C
S	OPDEF	DISP1	6435
S	OPDEF	DISP2	6436
C
C
S	OPDEF	SWAB	7431
S	OPDEF	SWBA	7447
C
S	OPDEF	MQA	7501
S	OPDEF	MQL	7421
S	OPDEF   KRS	6034
S	OPDEF	BSW	7002
C
C
C	5-LINE BUFFER NOTATION
C
C	J11 J12 J13 J14 J15
C	J21 J22 J23 J24 J25
C	J41 J42 J43 J44 J45
C	J51 J52 J53 J54 J55
C	[0] INITIALIZATION
C	[0.1] INITIALIZATION
	WRITE(1,995)
	WRITE(3,995)
995	FORMAT(' FILGAP 2/6/78 - 4:06PM')
	ET=TIMER(0)
	CALL DAYTIME(1)
	CALL DAYTIME(3)
C
C
C
C	[0.2] VERIFY BM SPECS
S	JMS CKIN
S	JMS CKOUT
C@@S	JMS CKIN2
C
C
C	[1] FILTER THE IMAGE.
	DO 200 IY1=KY1,KY2
	IY=IY1-1
S	TAD \IY
S	DISP2
C
C
C	GET A NEW BUFFER
S	JMS READNEXTLINE
C
C
C	[1.1] PROCESS A LINE
	DO 210 IX1=KX1,KX2
	IX=IX1-1
S	TAD \IX
S	DISP1
C
S	JMS GET5X5
C
C	PROCESS THE 8 FILTERS!
C		0  0 +4  0  0
C		0  0 +2  0  0
C	a      -2 -1 -6 -1 -2
C		0  0 +2  0  0
C		0  0 +4  0  0
C
C	GET + (A) SUM
S	TAD \J13
S	CLL RTL /*4
S	TAD \J23 /*2
S	TAD \J23
S	DCA 7
S	TAD \J53
S	CLL RTL /*4
S	TAD 7
S	TAD \J43 /*2
S	TAD \J43
S	DCA 7
C
C	GET - (A) SUM
S	TAD \J33
S	CLL RAL /*2
S	TAD \J33
S	CLL RAL /(3*J33)*2
S	TAD \J31
S	TAD \J31
S	TAD \J32
S	TAD \J34
S	TAD \J35
S	TAD \J35
S	CIA
S	TAD 7
S	DCA \IFA
C
C		0  0 +2 +2  0
C	       -1  0 +1 +1  0
C	b      -1 -1 -6 -1 -1
C		0 +1 +1  0 -1
C		0 +2 +2  0  0
C
C	GET + (B) SUM
S	TAD \J13
S	TAD \J13
S	TAD \J14
S	TAD \J14
S	TAD \J23
S	TAD \J24
S	TAD \J42
S	TAD \J43
S	TAD \J52
S	TAD \J52
S	TAD \J53
S	TAD \J53
S	DCA 7
C
C	GET - (B) SUM
S	TAD \J33
S	CLL RAL /*2
S	TAD \J33
S	CLL RAL /(3*J33)*2
S	TAD \J13
S	TAD \J12
S	TAD \J14
S	TAD \J15
S	CIA
S	TAD 7
S	DCA \IFB
C
C
C
C	       -2  0  0  0 +4
C	        0 -1  0 +2  0
C	c       0  0 -6  0  0
C		0 +2  0 -1  0
C	       +4  0  0  0 -2
C
C	GET + (C) SUM
S	TAD \J15
S	CLL RTL /*4
S	TAD \J24
S	TAD \J24
S	TAD \J42
S	TAD \J42
S	DCA 7
S	TAD \J51
S	CLL RTL /*4
S	TAD 7
S	DCA 7
S	DCA 7
C
C	GET - (C) SUM
S	TAD \J33
S	CLL RAL /*2
S	TAD \J33
S	CLL RAL /(3*J33)*2
S	TAD \J13
S	TAD \J13
S	TAD \J22
S	TAD \J44
S	TAD \J55
S	TAD \J55
S	CIA
S	TAD 7
S	DCA \IFC
C	        0 +2 +2  0  0
C	        0 +1 +1  0 -1
C	d      -1 -1 -6 -1 -1
C	       -1  0 +1 +1  0
C	        0  0 +2 +2  0
C
C	The  filters a', b', c' and d' are filters a, b, c, and
C        d rotated 90 degrees.
C
C	        0  0 -2  0  0
C	        0  0 -1  0  0
C	a'     +4 +2 -6 +2 +4
C	        0  0 -1  0  0
C	        0  0 -2  0  0
C
C	        0  0 -1 -1  0
C	       +2 +1 -1  0  0
C	b'     +2 +1 -6 +1 +2
C	        0  0 -1 +1 +2
C	        0 -1 -1  0  0
C
C	       +4  0  0  0 -2
C	        0 +2  0 -1  0
C	c'      0  0 -6  0  0
C	        0 -1  0 +2  0
C	       -2  0  0  0 +4
C
C	        0 -1 -1  0  0
C	        0  0 -1 +1 +2
C	d'     +2 +1 -6 +1 +2
C	       +2 +1 -1  0  0
C	        0  0 -1 -1  0
C
210	CONTINUE
C
C	WRITE OUT THE LINE
	MEM=JBM
	IBYTE=JHGH
S	TAD \KPTR3
S	DCA WROUT#
S	TAD (6261 /CDF 60
S	DCA WROUT
C
S	CALL 2,T3BUF
S WROUT,	ARG WROUT
S	ARG (3
C
200	CONTINUE
C
C
C	[999] RETURN
	GOTO 998
999	WRITE(1,996)
996	FORMAT('BAD BM SPECIFICATION!')
998	ET=TIMER(1)
	CALL CHAIN('BMON2')
C***************************************************
C	*PROCEDURE      I N I T B U F
C******************************************************
C
C
C	INIT THE TRIPLE LINE BUFFER
S	CPAGE 3
SRINITBUFF,	JMP I INITBUFF
S INITBUFF,	0 /ENTRY
C
C	[IN.1] SET THE RING POINTERS
	KPTR1=1024
	KPTR2=0
	KPTR3=256
	KPTR4=512
	KPTR5=768
C
C
C	[IN.2] ZERO FIELD 6
S	DCA 7
S	CPAGE 10
S	DCA \IZ
S	6261 /CDF 60
SZBUF,	DCAI 7
S	6211 /CDF COMMON
S	ISZ 7
S	JMP ZBUF
C
C	[IN.3] LOAD BUFFERS FROM BMI
	MEM=IBM1
	IBYTE=IHGH1
C
C	LOAD BUF(KPTR3)<==KY1
	IY=KY1-1
S	TAD \KPTR3
S	DCA LB1#
S	TAD (6261 /CDF 60
S	DCA LB1
S	CALL 2,T3BUF
S LB1,	ARG LB1
S	ARG (2
C
C	LOAD BUF(KPTR4)<==KY1+1
	IY=KY1
S	TAD \KPTR4
S	DCA LB2#
S	TAD (6261 /CDF 60
S	DCA LB2
S	CALL 2,T3BUF
S LB2,	ARG LB2
S	ARG (2
C
C	LOAD BUF(KPTR5)<==KY1+2
	IY=KY1+1
S	TAD \KPTR5
S	DCA LB3#
S	TAD (6261 /CDF 60
S	DCA LB3
S	CALL 2,T3BUF
S LB3,	ARG LB3
S	ARG (2
C
S	JMP RINITBUFF /OK.
C***************************************************
C	*PROCEDURE      R E A D N E X T B U F
C******************************************************
C
C
C	READNEXT THE TRIPLE LINE BUFFER
S	CPAGE 3
SRREADNEXTBUFF,	JMP I READNEXTBUFF
S READNEXTBUFF,	0 /ENTRY
C
C	[RNB.1] IF IY1>KY1
	IYSAVE=IY
C		THEN INCREMENT THE RING POINTERS
C		ELSE INIT POINTERS AND BUFFER AND RETURN;
S	TAD \IY1
S	CIA
S	TAD \KY1
S	SZA CLA
S	JMP \1810 />
C	GO INIT
S	JMS INITBUF
	IY=IYSAVE
S	JMP RREADNEXTBUFF
C
C	ELSE ROTATE BUFFER POINTERS
1810	IZ=KPTR1
	KPTR1=KPTR2
	KPTR2=KPTR3
	KPTR3=KPTR4
	KPTR4=KPTR5
	KPTR5=IZ
C
C
C	[RNB.2] LOAD BUFFER KPTR5 FROM LINE IY1+2 MIN 255;
	MEM=IBM1
	IBYTE=IHGH1
C	LOAD BUF(KPTR5)<==MIN(IY1+2,255)
	IY=IY1+1
	IF(IY-256)1811,1820,1820
S\1811,	TAD \KPTR5
S	DCA LB4#
S	TAD (6261 /CDF 60
S	DCA LB4
S	CALL 2,T3BUF
S LB4,	ARG LB4
S	ARG (2
C
	IY=IYSAVE
C
C
C	[RNB.3] LOAD NEXT BUFFER WITH ZEROS
S\1820,	CLA CMA
S	TAD \KPTR3
S	DCA 11 /AUTOINDEX
	DO 1821 IX=1,256
S	CPAGE 6
S	DCA \IZ
S	6261 /CDF 60
S	DCAI 11
S	6211 /CDF 10
1821	CONTINUE
	IY=IYSAVE
S	JMP RREADNEXTBUF
S	JMP RREADNEXTBUFF /OK.
C***************************************************
C	*PROCEDURE      G E T 5 X 5
C******************************************************
C
C
C	GET THE CURRENT NEIGHBORHOOD IN THE 5-LINE BUFFER
C	CENTERED AT IX (ZEROS AT END POINTS) INTO Jx,y.
S	CPAGE 3
SRGET5X5,	JMP I GET5X5
S GET5X5,	0 /ENTRY
C
C
C	[GET.1] SET THE 5 POINTERS INTO AUTOINDEX REG
S	CLA CMA
S	TAD \KPTR1
S	DCA 11
C
S	CLA CMA
S	TAD \KPTR2
S	DCA 12
C
S	CLA CMA
S	TAD \KPTR3
S	DCA 13
C
S	CLA CMA
S	TAD \KPTR4
S	DCA 14
C
S	CLA CMA
S	TAD \KTR5
S	DCA 15
C
C
C	[GET.2] READ THE LINES
S	CPAGE 15
S	DCA \IZ
S	TADI 11
S	DCA 25
S	TADI 12
S	DCA 26
S	TADI 13
S	DCA 27
S	TADI 14
S	DCA 30
S	TADI 15
S	6211
S	DCA \J15
S	TAD 25
S	DCA \J11
S	TAD 26
S	DCA \J12
S	TAD 27
S	DCA \J13
S	TAD 30
S	DCA \J14
C
S	CPAGE 15
S	DCA \IZ
S	TADI 11
S	DCA 25
S	TADI 12
S	DCA 26
S	TADI 13
S	DCA 27
S	TADI 14
S	DCA 30
S	TADI 15
S	6211
S	DCA \J25
S	TAD 25
S	DCA \J21
S	TAD 26
S	DCA \J22
S	TAD 27
S	DCA \J23
S	TAD 30
S	DCA \J24
C
S	CPAGE 15
S	DCA \IZ
S	TADI 11
S	DCA 25
S	TADI 12
S	DCA 26
S	TADI 13
S	DCA 27
S	TADI 14
S	DCA 30
S	TADI 15
S	6211
S	DCA \J35
S	TAD 25
S	DCA \J31
S	TAD 26
S	DCA \J32
S	TAD 27
S	DCA \J33
S	TAD 30
S	DCA \J34
C
S	CPAGE 15
S	DCA \IZ
S	TADI 11
S	DCA 25
S	TADI 12
S	DCA 26
S	TADI 13
S	DCA 27
S	TADI 14
S	DCA 30
S	TADI 15
S	6211
S	DCA \J45
S	TAD 25
S	DCA \J41
S	TAD 26
S	DCA \J42
S	TAD 27
S	DCA \J43
S	TAD 30
S	DCA \J44
C
S	CPAGE 15
S	DCA \IZ
S	TADI 11
S	DCA 25
S	TADI 12
S	DCA 26
S	TADI 13
S	DCA 27
S	TADI 14
S	DCA 30
S	TADI 15
S	6211
S	DCA \J55
S	TAD 25
S	DCA \J51
S	TAD 26
S	DCA \J52
S	TAD 27
S	DCA \J53
S	TAD 30
S	DCA \J54
C
S	JMP RGET5X5
C***************************************************
C	*PROCEDURE      C K O U T
C******************************************************
C
C
C	CHECK WHETHER THE OUTPUT BM SPEC IS LEGAL ELSE GOTO 999.
S	CPAGE 3
SRCKOUT,	JMP I CKOUT
S CKOUT,	0 /ENTRY
C
C	[1] TEST IF KOUTFILE="BM"
S	TAD \KOUTFILE
S	CIA
S	TAD BMTEXT
S	SZA CLA
S	JMP \999 /FAILED
C
C	[2] TEST IF (KOUTFILE(2) LAND '7700)=DIGIT
S	TAD \KOUTFILE#
S	BSW
S	AND (0077
S	TAD (-60 /"0"
S	SPA
S	JMP \999 /NO, FAILED
S	TAD (-D8 /"7" TEST
S	SMA CLA
S	JMP \999 /FAILED
S	JMP RCKOUT /OK.
C
C
C***************************************************
C	*PROCEDURE      C K I N
C******************************************************
C
C
C	CHECK WHETHER THE INPUT BM SPEC IS LEGAL ELSE GOTO 999.
S	CPAGE 3
SRCKIN,	JMP I CKIN
S CKIN,	0 /ENTRY
C
C	[1] TEST IF BMI1="BM"
S	TAD \SFILE
S	CIA
S	TAD BMTEXT
S	SZA CLA
S	JMP \999 /FAILED
C
C	[2] TEST IF (BMI1(2) LAND '7700)=DIGIT
S	TAD \SFILE#
S	BSW
S	AND (0077
S	TAD (-60 /"0"
S	SPA
S	JMP \999 /NO, FAILED
S	TAD (-D8 /"7" TEST
S	SMA CLA
S	JMP \999 /FAILED
S	JMP RCKIN /OK.
C
C
C***************************************************
C	*PROCEDURE      C K I N 2
C******************************************************
C
C
C	CHECK WHETHER THE INPUT BM SPEC IS LEGAL ELSE GOTO 999.
S	CPAGE 3
SRCKIN2,	JMP I CKIN2
S CKIN2,	0 /ENTRY
C
C	[1] CHECK FIRST IBM1 SPEC
S	JMS CKIN
C
C
C	[2] TEST IF BMI2="BM"
S	TAD \SEXT
S	CIA
S	TAD BMTEXT
S	SZA CLA
S	JMP \999 /FAILED
C
C	[3] TEST IF (BMI2((6) LAND '7700)=DIGIT
S	TAD \SEXT#
S	BSW
S	AND (0077
S	TAD (-60 /"0"
S	SPA
S	JMP \999 /NO, FAILED
S	TAD (-D8 /"7" TEST
S	SMA CLA
S	JMP \999 /FAILED
S	JMP RCKIN2 /OK.
C
C
C************** P A R A M E T E R S *************
	J11=0
	J12=0
	J13=0
	J14=0
	J15=0
	J21=0
	J22=0
	J23=0
	J24=0
	J25=0
	J31=0
	J32=0
	J33=0
	J34=0
	J35=0
	J41=0
	J42=0
	J43=0
	J44=0
	J45=0
	J51=0
	J52=0
	J53=0
	J54=0
	J55=0
C
	IFA=0
	IFB=0
	IFC=0
	IFD=0
	IFAP=0
	IFBP=0
	IFCP=0
	IFDP=0
S BMTEXT,	TEXT /BM/
	END