NAME
Image::Leptonica::Func::sel1
VERSION
version 0.04
sel1.c
sel1.c
    Basic ops on Sels and Selas
       Create/destroy/copy:
          SELA      *selaCreate()
          void       selaDestroy()
          SEL       *selCreate()
          void       selDestroy()
          SEL       *selCopy()
          SEL       *selCreateBrick()
          SEL       *selCreateComb()
       Helper proc:
          l_int32  **create2dIntArray()
       Extension of sela:
          SELA      *selaAddSel()
          static l_int32  selaExtendArray()
       Accessors:
          l_int32    selaGetCount()
          SEL       *selaGetSel()
          char      *selGetName()
          l_int32    selSetName()
          l_int32    selaFindSelByName()
          l_int32    selGetElement()
          l_int32    selSetElement()
          l_int32    selGetParameters()
          l_int32    selSetOrigin()
          l_int32    selGetTypeAtOrigin()
          char      *selaGetBrickName()
          char      *selaGetCombName()
   static char      *selaComputeCompositeParameters()
          l_int32    getCompositeParameters()
          SARRAY    *selaGetSelnames()
       Max translations for erosion and hmt
          l_int32    selFindMaxTranslations()
       Rotation by multiples of 90 degrees
          SEL       *selRotateOrth()
       Sela and Sel serialized I/O
          SELA      *selaRead()
          SELA      *selaReadStream()
          SEL       *selRead()
          SEL       *selReadStream()
          l_int32    selaWrite()
          l_int32    selaWriteStream()
          l_int32    selWrite()
          l_int32    selWriteStream()
       Building custom hit-miss sels from compiled strings
          SEL       *selCreateFromString()
          char      *selPrintToString()     [for debugging]
       Building custom hit-miss sels from a simple file format
          SELA      *selaCreateFromFile()
          static SEL *selCreateFromSArray()
       Making hit-only sels from Pta and Pix
          SEL       *selCreateFromPta()
          SEL       *selCreateFromPix()
       Making hit-miss sels from Pix and image files
          SEL       *selReadFromColorImage()
          SEL       *selCreateFromColorPix()
       Printable display of sel
          PIX       *selDisplayInPix()
          PIX       *selaDisplayInPix()
   Usage notes:
      In this file we have seven functions that make sels:
        (1)  selCreate(), with input (h, w, [name])
             The generic function.  Roll your own, using selSetElement().
        (2)  selCreateBrick(), with input (h, w, cy, cx, val)
             The most popular function.  Makes a rectangular sel of
             all hits, misses or don't-cares.  We have many morphology
             operations that create a sel of all hits, use it, and
             destroy it.
        (3)  selCreateFromString() with input (text, h, w, [name])
             Adam Langley's clever function, allows you to make a hit-miss
             sel from a string in code that is geometrically laid out
             just like the actual sel.
        (4)  selaCreateFromFile() with input (filename)
             This parses a simple file format to create an array of
             hit-miss sels.  The sel data uses the same encoding
             as in (3), with geometrical layout enforced.
        (5)  selCreateFromPta() with input (pta, cy, cx, [name])
             Another way to make a sel with only hits.
        (6)  selCreateFromPix() with input (pix, cy, cx, [name])
             Yet another way to make a sel from hits.
        (7)  selCreateFromColorPix() with input (pix, name).
             Another way to make a general hit-miss sel, starting with
             an image editor.
      In addition, there are three functions in selgen.c that
      automatically generate a hit-miss sel from a pix and
      a number of parameters.  This is useful for problems like
      "find all patterns that look like this one."
      Consistency, being the hobgoblin of small minds,
      is adhered to here in the dimensioning and accessing of sels.
      Everything is done in standard matrix (row, column) order.
      When we set specific elements in a sel, we likewise use
      (row, col) ordering:
           selSetElement(), with input (row, col, type)
FUNCTIONS
create2dIntArray
l_int32 ** create2dIntArray ( l_int32 sy, l_int32 sx )
create2dIntArray()
    Input:  sy (rows == height)
            sx (columns == width)
    Return: doubly indexed array (i.e., an array of sy row pointers,
            each of which points to an array of sx ints)
Notes:
    (1) The array[sy][sx] is indexed in standard "matrix notation",
        with the row index first.
selCopy
SEL * selCopy ( SEL *sel )
selCopy()
    Input:  sel
    Return: a copy of the sel, or null on error
selCreate
SEL * selCreate ( l_int32 height, l_int32 width, const char *name )
selCreate()
    Input:  height, width
            name (<optional> sel name; can be null)
    Return: sel, or null on error
Notes:
    (1) selCreate() initializes all values to 0.
    (2) After this call, (cy,cx) and nonzero data values must be
        assigned.  If a text name is not assigned here, it will
        be needed later when the sel is put into a sela.
selCreateBrick
SEL * selCreateBrick ( l_int32 h, l_int32 w, l_int32 cy, l_int32 cx, l_int32 type )
selCreateBrick()
    Input:  height, width
            cy, cx  (origin, relative to UL corner at 0,0)
            type  (SEL_HIT, SEL_MISS, or SEL_DONT_CARE)
    Return: sel, or null on error
Notes:
    (1) This is a rectangular sel of all hits, misses or don't cares.
selCreateComb
SEL * selCreateComb ( l_int32 factor1, l_int32 factor2, l_int32 direction )
selCreateComb()
    Input:  factor1 (contiguous space between comb tines)
            factor2 (number of comb tines)
            direction (L_HORIZ, L_VERT)
    Return: sel, or null on error
Notes:
    (1) This generates a comb Sel of hits with the origin as
        near the center as possible.
selCreateFromColorPix
SEL * selCreateFromColorPix ( PIX *pixs, char *selname )
selCreateFromColorPix()
    Input:  pixs (cmapped or rgb)
            selname (<optional> sel name; can be null)
    Return: sel if OK, null on error
Notes:
    (1) The sel size is given by the size of pixs.
    (2) In pixs, hits are represented by green pixels, misses by red
        pixels, and don't-cares by white pixels.
    (3) In pixs, there may be no misses, but there must be at least 1 hit.
    (4) At most there can be only one origin pixel, which is optionally
        specified by using a lower-intensity pixel:
          if a hit:  dark green
          if a miss: dark red
          if a don't care: gray
        If there is no such pixel, the origin defaults to the approximate
        center of the sel.
selCreateFromPix
SEL * selCreateFromPix ( PIX *pix, l_int32 cy, l_int32 cx, const char *name )
selCreateFromPix()
    Input:  pix
            cy, cx (origin of sel)
            name (<optional> sel name; can be null)
    Return: sel, or null on error
Notes:
    (1) The origin must be positive.
selCreateFromPta
SEL * selCreateFromPta ( PTA *pta, l_int32 cy, l_int32 cx, const char *name )
selCreateFromPta()
    Input:  pta
            cy, cx (origin of sel)
            name (<optional> sel name; can be null)
    Return: sel (of minimum required size), or null on error
Notes:
    (1) The origin and all points in the pta must be positive.
selCreateFromString
SEL * selCreateFromString ( const char *text, l_int32 h, l_int32 w, const char *name )
selCreateFromString()
    Input:  text
            height, width
            name (<optional> sel name; can be null)
    Return: sel of the given size, or null on error
Notes:
    (1) The text is an array of chars (in row-major order) where
        each char can be one of the following:
           'x': hit
           'o': miss
           ' ': don't-care
    (2) Use an upper case char to indicate the origin of the Sel.
        When the origin falls on a don't-care, use 'C' as the uppecase
        for ' '.
    (3) The text can be input in a format that shows the 2D layout; e.g.,
            static const char *seltext = "x    "
                                         "x Oo "
                                         "x    "
                                         "xxxxx";
selDestroy
void selDestroy ( SEL **psel )
selDestroy()
    Input:  &sel (<to be nulled>)
    Return: void
selDisplayInPix
PIX * selDisplayInPix ( SEL *sel, l_int32 size, l_int32 gthick )
selDisplayInPix()
    Input:  sel
            size (of grid interiors; odd; minimum size of 13 is enforced)
            gthick (grid thickness; minimum size of 2 is enforced)
    Return: pix (display of sel), or null on error
Notes:
    (1) This gives a visual representation of a general (hit-miss) sel.
    (2) The empty sel is represented by a grid of intersecting lines.
    (3) Three different patterns are generated for the sel elements:
        - hit (solid black circle)
        - miss (black ring; inner radius is radius2)
        - origin (cross, XORed with whatever is there)
selFindMaxTranslations
l_int32 selFindMaxTranslations ( SEL *sel, l_int32 *pxp, l_int32 *pyp, l_int32 *pxn, l_int32 *pyn )
selFindMaxTranslations()
    Input:  sel
            &xp, &yp, &xn, &yn  (<return> max shifts)
    Return: 0 if OK; 1 on error
Note: these are the maximum shifts for the erosion operation.
      For example, when j < cx, the shift of the image
      is +x to the cx.  This is a positive xp shift.
selGetElement
l_int32 selGetElement ( SEL *sel, l_int32 row, l_int32 col, l_int32 *ptype )
selGetElement()
    Input:  sel
            row
            col
            &type  (<return> SEL_HIT, SEL_MISS, SEL_DONT_CARE)
    Return: 0 if OK; 1 on error
selGetName
char * selGetName ( SEL *sel )
selGetName()
    Input:  sel
    Return: sel name (not copied), or null if no name or on error
selGetParameters
l_int32 selGetParameters ( SEL *sel, l_int32 *psy, l_int32 *psx, l_int32 *pcy, l_int32 *pcx )
selGetParameters()
    Input:  sel
            &sy, &sx, &cy, &cx (<optional return>; each can be null)
    Return: 0 if OK, 1 on error
selGetTypeAtOrigin
l_int32 selGetTypeAtOrigin ( SEL *sel, l_int32 *ptype )
selGetTypeAtOrigin()
    Input:  sel
            &type  (<return> SEL_HIT, SEL_MISS, SEL_DONT_CARE)
    Return: 0 if OK; 1 on error or if origin is not found
selPrintToString
char * selPrintToString ( SEL *sel )
selPrintToString()
    Input:  sel
    Return: str (string; caller must free)
Notes:
    (1) This is an inverse function of selCreateFromString.
        It prints a textual representation of the SEL to a malloc'd
        string.  The format is the same as selCreateFromString
        except that newlines are inserted into the output
        between rows.
    (2) This is useful for debugging.  However, if you want to
        save some Sels in a file, put them in a Sela and write
        them out with selaWrite().  They can then be read in
        with selaRead().
selRead
SEL * selRead ( const char *fname )
selRead()
    Input:  filename
    Return: sel, or null on error
selReadFromColorImage
SEL * selReadFromColorImage ( const char *pathname )
selReadFromColorImage()
    Input:  pathname
    Return: sel if OK; null on error
Notes:
    (1) Loads an image from a file and creates a (hit-miss) sel.
    (2) The sel name is taken from the pathname without the directory
        and extension.
selReadStream
SEL * selReadStream ( FILE *fp )
selReadStream()
    Input:  stream
    Return: sel, or null on error
selRotateOrth
SEL * selRotateOrth ( SEL *sel, l_int32 quads )
selRotateOrth()
    Input:  sel
            quads (0 - 4; number of 90 degree cw rotations)
    Return: seld, or null on error
selSetElement
l_int32 selSetElement ( SEL *sel, l_int32 row, l_int32 col, l_int32 type )
selSetElement()
    Input:  sel
            row
            col
            type  (SEL_HIT, SEL_MISS, SEL_DONT_CARE)
    Return: 0 if OK; 1 on error
Notes:
    (1) Because we use row and column to index into an array,
        they are always non-negative.  The location of the origin
        (and the type of operation) determine the actual
        direction of the rasterop.
selSetName
l_int32 selSetName ( SEL *sel, const char *name )
selSetName()
    Input:  sel
            name (<optional>; can be null)
    Return: 0 if OK, 1 on error
Notes:
    (1) Always frees the existing sel name, if defined.
    (2) If name is not defined, just clears any existing sel name.
selSetOrigin
l_int32 selSetOrigin ( SEL *sel, l_int32 cy, l_int32 cx )
selSetOrigin()
    Input:  sel
            cy, cx
    Return: 0 if OK; 1 on error
selWrite
l_int32 selWrite ( const char *fname, SEL *sel )
selWrite()
    Input:  filename
            sel
    Return: 0 if OK, 1 on error
selWriteStream
l_int32 selWriteStream ( FILE *fp, SEL *sel )
selWriteStream()
    Input:  stream
            sel
    Return: 0 if OK, 1 on error
selaAddSel
l_int32 selaAddSel ( SELA *sela, SEL *sel, const char *selname, l_int32 copyflag )
selaAddSel()
    Input:  sela
            sel to be added
            selname (ignored if already defined in sel;
                     req'd in sel when added to a sela)
            copyflag (for sel: 0 inserts, 1 copies)
    Return: 0 if OK; 1 on error
Notes:
    (1) This adds a sel, either inserting or making a copy.
    (2) Because every sel in a sela must have a name, it copies
        the input name if necessary.  You can input NULL for
        selname if the sel already has a name.
selaCreate
SELA * selaCreate ( l_int32 n )
selaCreate()
    Input:  n (initial number of sel ptrs; use 0 for default)
    Return: sela, or null on error
selaCreateFromFile
SELA * selaCreateFromFile ( const char *filename )
selaCreateFromFile()
    Input:  filename
    Return: sela, or null on error
Notes:
    (1) The file contains a sequence of Sel descriptions.
    (2) Each Sel is formatted as follows:
         - Any number of comment lines starting with '#' are ignored
         - The next line contains the selname
         - The next lines contain the Sel data.  They must be
           formatted similarly to the string format in
           selCreateFromString(), with each line beginning and
           ending with a double-quote, and showing the 2D layout.
         - Each Sel ends when a blank line, a comment line, or
           the end of file is reached.
    (3) See selCreateFromString() for a description of the string
        format for the Sel data.  As an example, here are the lines
        of is a valid file for a single Sel.  In the file, all lines
        are left-justified:
                  # diagonal sel
                  sel_5diag
                  "x    "
                  " x   "
                  "  X  "
                  "   x "
                  "    x"
selaDestroy
void selaDestroy ( SELA **psela )
selaDestroy()
    Input:  &sela (<to be nulled>)
    Return: void
selaDisplayInPix
PIX * selaDisplayInPix ( SELA *sela, l_int32 size, l_int32 gthick, l_int32 spacing, l_int32 ncols )
selaDisplayInPix()
    Input:  sela
            size (of grid interiors; odd; minimum size of 13 is enforced)
            gthick (grid thickness; minimum size of 2 is enforced)
            spacing (between sels, both horizontally and vertically)
            ncols (number of sels per "line")
    Return: pix (display of all sels in sela), or null on error
Notes:
    (1) This gives a visual representation of all the sels in a sela.
    (2) See notes in selDisplayInPix() for display params of each sel.
    (3) This gives the nicest results when all sels in the sela
        are the same size.
selaFindSelByName
l_int32 selaFindSelByName ( SELA *sela, const char *name, l_int32 *pindex, SEL **psel )
selaFindSelByName()
    Input:  sela
            sel name
            &index (<optional, return>)
            &sel  (<optional, return> sel (not a copy))
    Return: 0 if OK; 1 on error
selaGetBrickName
char * selaGetBrickName ( SELA *sela, l_int32 hsize, l_int32 vsize )
selaGetBrickName()
    Input:  sela
            hsize, vsize (of brick sel)
    Return: sel name (new string), or null if no name or on error
selaGetCombName
char * selaGetCombName ( SELA *sela, l_int32 size, l_int32 direction )
selaGetCombName()
    Input:  sela
            size (the product of sizes of the brick and comb parts)
            direction (L_HORIZ, L_VERT)
    Return: sel name (new string), or null if name not found or on error
Notes:
    (1) Combs are by definition 1-dimensional, either horiz or vert.
    (2) Use this with comb Sels; e.g., from selaAddDwaCombs().
selaGetCount
l_int32 selaGetCount ( SELA *sela )
selaGetCount()
    Input:  sela
    Return: count, or 0 on error
selaGetSel
SEL * selaGetSel ( SELA *sela, l_int32 i )
selaGetSel()
    Input:  sela
            index of sel to be retrieved (not copied)
    Return: sel, or null on error
Notes:
    (1) This returns a ptr to the sel, not a copy, so the caller
        must not destroy it!
selaGetSelnames
SARRAY * selaGetSelnames ( SELA *sela )
selaGetSelnames()
    Input:  sela
    Return: sa (of all sel names), or null on error
selaRead
SELA * selaRead ( const char *fname )
selaRead()
    Input:  filename
    Return: sela, or null on error
selaReadStream
SELA * selaReadStream ( FILE *fp )
selaReadStream()
    Input:  stream
    Return: sela, or null on error
selaWrite
l_int32 selaWrite ( const char *fname, SELA *sela )
selaWrite()
    Input:  filename
            sela
    Return: 0 if OK, 1 on error
selaWriteStream
l_int32 selaWriteStream ( FILE *fp, SELA *sela )
selaWriteStream()
    Input:  stream
            sela
    Return: 0 if OK, 1 on error
AUTHOR
Zakariyya Mughal <zmughal@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2014 by Zakariyya Mughal.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.