"

 COPYRIGHT (c) 1993 by Claus Gittinger

              All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

Image subclass:#Depth1Image

         instanceVariableNames:''

         classVariableNames:''

         poolDictionaries:''

         category:'Graphics-Display Objects'

!

Depth1Image comment:'

COPYRIGHT (c) 1993 by Claus Gittinger

              All Rights Reserved

'!

!Depth1Image class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1993 by Claus Gittinger

              All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

!

version

"

"

!

documentation

"

    this class represents bilevel (1 bit / pixel) images.

    It mainly consists of methods already implemented in Image,

    reimplemented here for more performance.

"

! !

!Depth1Image methodsFor:'accessing'!

bitsPerPixel

    "return the number of bits per pixel"

    ^ 1

!

bitsPerRow

    "return the number of bits in one scanline of the image"

    ^  width

!

bitsPerSample

    "return the number of bits per sample.

     The return value is an array of bits-per-plane."

    ^ #(1)

!

bytesPerRow

    "return the number of bytes in one scanline of the image"

    |nbytes|

    nbytes := width // 8.

    ((width \\ 8) ~~ 0) ifTrue:[

        ^ nbytes + 1

    ].

    ^ nbytes

!

samplesPerPixel

    "return the number of samples per pixel in the image."

    ^ 1

!

valueAtX:x y:y

    "retrieve a pixel at x/y; return a pixel value.

     Pixels start at x=0 , y=0 for upper left pixel, end at

     x = width-1, y=height-1 for lower right pixel"

    |bytesPerRow "{Class: SmallInteger}"

     index       "{Class: SmallInteger}"

     byte        "{Class: SmallInteger}"

     mask        "{Class: SmallInteger}"|

%{  /* NOCONTEXT */

    if (__isByteArray(_INST(bytes))

     && _isSmallInteger(x)

     && _isSmallInteger(y)

     && _isSmallInteger(_INST(width)) ) {

        int _w = _intVal(_INST(width));

        int _y = _intVal(y);

        int _x = _intVal(x);

        unsigned _byte;

        _byte = _ByteArrayInstPtr(_INST(bytes))->ba_element[(_w + 7) / 8 * _y + (_x / 8)];

        RETURN( (_byte & (0x80 >> (_x % 8))) ? _MKSMALLINT(1) : _MKSMALLINT(0) );

    }

%}

.

    bytesPerRow := width // 8.

    ((width \\ 8) ~~ 0) ifTrue:[

        bytesPerRow := bytesPerRow + 1

    ].

    index := (bytesPerRow * y) + 1 + (x // 8).

    "left pixel is in high bit"

    byte := bytes at:index.

    mask := #(16r80 16r40 16r20 16r10 16r08 16r04 16r02 16r01) at:((x \\ 8) + 1).

    (byte bitAnd:mask) == 0 ifTrue:[^ 0].

    ^ 1

!

atX:x y:y

    "retrieve a pixel at x/y; return a color.

     Pixels start at x=0 , y=0 for upper left pixel, end at

     x = width-1, y=height-1 for lower right pixel"

    |lineIndex "{ Class: SmallInteger }"

     byte      "{ Class: SmallInteger }"

     shift     "{ Class: SmallInteger }"

     value     "{ Class: SmallInteger }"|

    lineIndex := (self bytesPerRow * y) + 1.

    "left pixel is in high bit"

    byte := bytes at:(lineIndex + (x // 8)).

    shift := #(-7 -6 -5 -4 -3 -2 -1 0) at:((x \\ 8) + 1).

    value := (byte bitShift:shift) bitAnd:1.

    photometric == #whiteIs0 ifTrue:[

        (value == 0) ifTrue:[

            ^ Color white

        ].

        ^ Color black

    ].

    photometric == #blackIs0 ifTrue:[

        (value == 0) ifTrue:[

            ^ Color black

        ].

        ^ Color white

    ].

    photometric ~~ #palette ifTrue:[

        self error:'format not supported'.

        ^ nil

    ].

    value := value + 1.

    ^ Color red:(((colorMap at:1) at:value) * (100.0 / 255.0))

          green:(((colorMap at:2) at:value) * (100.0 / 255.0))

           blue:(((colorMap at:3) at:value) * (100.0 / 255.0))

!

atX:x y:y putValue:aPixelValue

    "set the pixel at x/y to aPixelValue.

     Pixels start at x=0 , y=0 for upper left pixel, end at

     x = width-1, y=height-1 for lower right pixel"

    |bytesPerRow "{Class: SmallInteger}"

     index       "{Class: SmallInteger}"

     byte        "{Class: SmallInteger}"

     mask        "{Class: SmallInteger}"|

%{  /* NOCONTEXT */

    if (__isByteArray(_INST(bytes))

     && _isSmallInteger(x)

     && _isSmallInteger(y)

     && _isSmallInteger(_INST(width)) ) {

        int _w = _intVal(_INST(width));

        int _y = _intVal(y);

        int _x = _intVal(x);

        int _idx;

        _idx = (_w + 7) / 8 * _y + (_x / 8);

        if (aPixelValue == _MKSMALLINT(0)) {

            _ByteArrayInstPtr(_INST(bytes))->ba_element[_idx] &= ~(0x80 >> (_x % 8));

        } else {

            _ByteArrayInstPtr(_INST(bytes))->ba_element[_idx] |= (0x80 >> (_x % 8));

        }

        RETURN( self );

    }

%}

.

    bytesPerRow := width // 8.

    ((width \\ 8) ~~ 0) ifTrue:[

        bytesPerRow := bytesPerRow + 1

    ].

    index := (bytesPerRow * y) + 1 + (x // 8).

    "left pixel is in high bit"

    byte := bytes at:index.

    mask := #(16r80 16r40 16r20 16r10 16r08 16r04 16r02 16r01) at:((x \\ 8) + 1).

    aPixelValue == 0 ifTrue:[

        byte := byte bitAnd:(mask bitInvert)

    ] ifFalse:[

        byte := byte bitOr:mask

    ].

    bytes at:index put:byte

!

atX:x y:y put:aColor

    "set the pixel at x/y to aColor.

     Pixels start at x=0 , y=0 for upper left pixel, end at

     x = width-1, y=height-1 for lower right pixel.

     This method checks, if it is possible to store the color

     in the image; i.e. for b/w images, the color MUST be black

     or white; for palette images it must be present in the palette."

    |clr0 clr1|

    photometric == #whiteIs0 ifTrue:[

        clr0 := Color whilte.

        clr1 := Color black.

    ] ifFalse:[

        photometric == #blackIs0 ifTrue:[

            clr0 := Color black.

            clr1 := Color whilte.

        ] ifFalse:[

            photometric ~~ #palette ifTrue:[

                self error:'format not supported'.

                ^ nil

            ].

            clr0 := colorMap at:1.

            clr1 := colorMap at:2.

        ]

    ].

    aColor = clr0 ifTrue:[

        self atX:x y:y putValue:0.

        ^ self

    ].

    aColor = clr1 ifTrue:[

        self atX:x y:y putValue:1.

        ^ self

    ].

    "

     the color to be stored is not in the images

     colormap

    "

    self error:'invalid color'

!

atY:y from:xLow to:xHigh do:aBlock

    "perform aBlock for each pixel from x1 to x2 in row y.

     The block is passed the color at each pixel.

     This method allows slighly faster processing of an

     image than using atX:y:, since some processing can be

     avoided when going from pixel to pixel. However, for

     real image processing, specialized methods should be written."

    |srcIndex "{ Class: SmallInteger }"

     byte     "{ Class: SmallInteger }"

     mask     "{ Class: SmallInteger }"

     x1       "{ Class: SmallInteger }"

     x2       "{ Class: SmallInteger }"

     color0 color1 color|

    x1 := xLow.

    x2 := xHigh.

    srcIndex := (self bytesPerRow * y) + 1.

    "left pixel is in high bit"

    photometric == #whiteIs0 ifTrue:[

        color0 := Color white.

        color1 := Color black

    ] ifFalse:[

        photometric == #blackIs0 ifTrue:[

            color0 := Color black.

            color1 := Color white

        ] ifFalse:[

            photometric == #palette ifTrue:[

                color0 := Color red:(((colorMap at:1) at:1) * 100 / 255)

                              green:(((colorMap at:2) at:1) * 100 / 255)

                               blue:(((colorMap at:3) at:1) * 100 / 255).

                color1 := Color red:(((colorMap at:1) at:2) * 100 / 255)

                              green:(((colorMap at:2) at:2) * 100 / 255)

                               blue:(((colorMap at:3) at:2) * 100 / 255).

            ] ifFalse:[

                self error:'format not supported'.

                ^ nil

            ]

        ]

    ].

    srcIndex := srcIndex + (x1 // 8).

    mask := #[2r10000000 

              2r01000000

              2r00100000

              2r00010000

              2r00001000

              2r00000100

              2r00000010

              2r00000001] at:((x1 \\ 8) + 1).

    x1 to:x2 do:[:x |

        byte := bytes at:srcIndex.

        (byte bitAnd:mask) == 0 ifTrue:[

            color := color0

        ] ifFalse:[

            color := color1

        ].

        aBlock value:x value:color.

        mask := mask bitShift:-1.

        mask == 0 ifTrue:[

            mask := 2r10000000.

            srcIndex := srcIndex + 1

        ]

    ]

! !

!Depth1Image methodsFor:'converting greyscale images'!

greyImageAsFormOn:aDevice

    "convert a greyscale image to a device form"

    |f|

    f := Form width:width height:height fromArray:bytes on:aDevice.

    photometric == #blackIs0 ifTrue:[

        f function:#xor.

        f paint:(Color colorId:1).

        f fillRectangleX:0 y:0 width:width height:height

    ].

    ^ f

!

greyImageAsMonoFormOn:aDevice

    "convert to a monochrome form - thats easy"

    ^ self greyImageAsFormOn:aDevice

! !

!Depth1Image methodsFor:'magnification'!

magnifyRowFrom:srcBytes offset:srcStart  

          into:dstBytes offset:dstStart factor:mX

    "magnify a single pixel row - can only magnify by integer factors"

%{

    unsigned char *srcP, *dstP;

    int _mag;

    REGISTER int i;

    REGISTER unsigned char _byte;

    int _pixels, bpr;

    REGISTER int outcnt, bits, bit, mask, incnt;

    int shift;

    unsigned char byte1, byte2, byte3, byte4;

    /* helper for monochrome magnification by 2 */

    static unsigned char mag1[16] = {0x00, 0x03, 0x0c, 0x0f, 0x30, 0x33, 0x3c, 0x3f, 

                                     0xc0, 0xc3, 0xcc, 0xcf, 0xf0, 0xf3, 0xfc, 0xff};

    if (_isSmallInteger(srcStart) && _isSmallInteger(dstStart)

     && _isSmallInteger(_INST(width)) && _isSmallInteger(mX)

     && __isByteArray(srcBytes) && __isByteArray(dstBytes)) {

        _mag = _intVal(mX);

        srcP = _ByteArrayInstPtr(srcBytes)->ba_element - 1 + _intVal(srcStart);

        dstP = _ByteArrayInstPtr(dstBytes)->ba_element - 1 + _intVal(dstStart);

        _pixels = _intVal(_INST(width));

        switch (_mag) {

            case 1:

                break;

            case 2:

                /* tuned for this common case */

                while (_pixels > 0) {

                    _byte = *srcP++;

                    *dstP++ = mag1[ _byte >> 4 ];

                    if (_pixels > 4) {

                        *dstP++ = mag1[ _byte & 0x0F ];

                    }

                    _pixels -= 8;

                }

                break;

            case 4:

                /* tuned for this common case */

                while (_pixels > 0) {

                    _byte = *srcP++;

                    byte1 = mag1[_byte >> 4];

                    byte2 = mag1[byte1 & 0xF];

                    byte1 = mag1[byte1 >> 4];

                    byte3 = mag1[ _byte & 0x0F ];

                    byte4 = mag1[byte3 & 0xF];

                    byte3 = mag1[byte3 >> 4];

                    *dstP++ = byte1;

                    if (_pixels > 2) {

                        *dstP++ = byte2;

                        if (_pixels > 4) {

                            *dstP++ = byte3;

                            if (_pixels > 6) {

                                *dstP++ = byte4;

                            }

                        }

                    }

                    _pixels -= 8;

                }

                break;

            default:

                bits = 0, incnt = 0, outcnt = 0;

                mask = 0x80;

                _byte = *srcP++;

                while (_pixels--) {

                    if (_byte & mask)

                        bit = 1;

                    else

                        bit = 0;

                    incnt++;

                    if (incnt == 8) {

                        incnt = 0;

                        mask = 0x80;

                        _byte = *srcP++;

                    } else {

                        mask >>= 1;

                    }

                    for (i=_mag; i>0; i--) {

                        bits = (bits << 1) | bit;

                        outcnt++;

                        if (outcnt == 8) {

                            *dstP++ = bits;

                            bits = 0;

                            outcnt = 0;

                        }

                    }

                }

                break;

        }

        RETURN (self);

    }

%}

.

    self primitiveFailed

! !