CV/CV.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include <gdk-pixbuf/gdk-pixbuf.h>

#include <gperl.h>
#include <gtk2perl.h>

#define IW 80

#define RAND (seed = (seed + 7141) * 54773 % 134456)

#define LINELENGTH 240

#define ELLIPSIS "\xe2\x80\xa6"

static guint32 a85_val;
static guint a85_cnt;
static guchar a85_buf[LINELENGTH], *a85_ptr;

static void
a85_init (void)
{
  a85_cnt = 4;
  a85_ptr = a85_buf;
}

static void
a85_push (PerlIO *fp, guchar c)
{
  a85_val = a85_val << 8 | c;

  if (!--a85_cnt)
    {
      a85_cnt = 4;
      if (a85_val)
        {
          a85_ptr[4] = (a85_val % 85) + 33; a85_val /= 85; 
          a85_ptr[3] = (a85_val % 85) + 33; a85_val /= 85; 
          a85_ptr[2] = (a85_val % 85) + 33; a85_val /= 85; 
          a85_ptr[1] = (a85_val % 85) + 33; a85_val /= 85;
          a85_ptr[0] = (a85_val     ) + 33;

          a85_ptr += 5;
        }
      else
        *a85_ptr++ = 'z';

      if (a85_ptr >= a85_buf + sizeof (a85_buf) - 7)
        {
          *a85_ptr++ = '\n';
          PerlIO_write (fp, a85_buf, a85_ptr - a85_buf);
          a85_ptr = a85_buf;
        }
    }
    
}

static void
a85_finish (PerlIO *fp)
{
  while (a85_cnt != 4)
    a85_push (fp, 0);

  *a85_ptr++ = '~'; // probably buggy end-marker
  *a85_ptr++ = '>'; // probably buggy end-marker
  *a85_ptr++ = '\n';

  PerlIO_write (fp, a85_buf, a85_ptr - a85_buf);
}

static void
rgb_to_hsv (unsigned int  r, unsigned int  g, unsigned int  b,
            unsigned int *h, unsigned int *s, unsigned int *v)
{
  unsigned int mx = r; if (g > mx) mx = g; if (b > mx) mx = b;
  unsigned int mn = r; if (g < mn) mn = g; if (b < mn) mn = b;
  unsigned int delta = mx - mn;

  *v = mx;

  *s = mx ? delta * 255 / mx : 0;

  if (delta == 0)
    *h = 0;
  else
    {
      if (r == mx)
        *h = ((int)g - (int)b) * 255 / (int)(delta * 3);
      else if (g == mx)
        *h = ((int)b - (int)r) * 255 / (int)(delta * 3) + 52;
      else if (b == mx)
        *h = ((int)r - (int)g) * 255 / (int)(delta * 3) + 103;

      *h &= 255;
    }
}

/////////////////////////////////////////////////////////////////////////////

MODULE = Gtk2::CV PACKAGE = Gtk2::CV

PROTOTYPES: ENABLE

GdkPixbuf_noinc *
transpose (GdkPixbuf *pb)
        CODE:
{
        int w = gdk_pixbuf_get_width (pb);
        int h = gdk_pixbuf_get_height (pb);
        int bpp = gdk_pixbuf_get_n_channels (pb);
        int x, y, i;
        guchar *src = gdk_pixbuf_get_pixels (pb), *dst;
        int sstr = gdk_pixbuf_get_rowstride (pb), dstr;

        RETVAL = gdk_pixbuf_new (GDK_COLORSPACE_RGB, bpp == 4, 8, h, w);

        dst = gdk_pixbuf_get_pixels (RETVAL);
        dstr = gdk_pixbuf_get_rowstride (RETVAL);

        for (y = 0; y < h; y++)
          for (x = 0; x < w; x++)
            for (i = 0; i < bpp; i++)
              dst[y * bpp + x * dstr + i] = src[x * bpp + y * sstr + i];
}
        OUTPUT:
        RETVAL

GdkPixbuf_noinc *
flop (GdkPixbuf *pb)
        CODE:
{
        int w = gdk_pixbuf_get_width (pb);
        int h = gdk_pixbuf_get_height (pb);
        int bpp = gdk_pixbuf_get_n_channels (pb);
        int x, y, i;
        guchar *src = gdk_pixbuf_get_pixels (pb), *dst;
        int sstr = gdk_pixbuf_get_rowstride (pb), dstr;

        RETVAL = gdk_pixbuf_new (GDK_COLORSPACE_RGB, bpp == 4, 8, w, h);

        dst = gdk_pixbuf_get_pixels (RETVAL);
        dstr = gdk_pixbuf_get_rowstride (RETVAL);

        for (y = 0; y < h; y++)
          for (x = 0; x < w; x++)
            for (i = 0; i < bpp; i++)
              dst[(w - 1 - x) * bpp + y * dstr + i] = src[x * bpp + y * sstr + i];
}
        OUTPUT:
        RETVAL

#############################################################################

MODULE = Gtk2::CV PACKAGE = Gtk2::CV::Schnauzer

GdkPixbuf_noinc *
p7_to_pb (int w, int h, guchar *src)
        CODE:
{
        int x, y;
        guchar *dst, *d;
        int dstr;

        RETVAL = gdk_pixbuf_new (GDK_COLORSPACE_RGB, 0, 8,  w, h);
        dst = gdk_pixbuf_get_pixels (RETVAL);
        dstr = gdk_pixbuf_get_rowstride (RETVAL);

        for (y = 0; y < h; y++)
          for (d = dst + y * dstr, x = 0; x < w; x++)
            {
              *d++ = (((*src >> 5) & 7) * 255 + 4) / 7;
              *d++ = (((*src >> 2) & 7) * 255 + 4) / 7;
              *d++ = (((*src >> 0) & 3) * 255 + 2) / 3;

              src++;
            }
}
        OUTPUT:
        RETVAL

SV *
pb_to_p7 (GdkPixbuf *pb)
        CODE:
{
        int w = gdk_pixbuf_get_width  (pb);
        int h = gdk_pixbuf_get_height (pb);
        int x, y;
        guchar *dst;
        int bpp = gdk_pixbuf_get_n_channels (pb);
        guchar *src = gdk_pixbuf_get_pixels (pb);
        int sstr = gdk_pixbuf_get_rowstride (pb);
        int Er[IW], Eg[IW], Eb[IW];
        int seed = 77;

        RETVAL = newSV (w * h);
        SvPOK_only (RETVAL);
        SvCUR_set (RETVAL, w * h);

        dst = SvPVX (RETVAL);

        memset (Er, 0, sizeof (int) * IW);
        memset (Eg, 0, sizeof (int) * IW);
        memset (Eb, 0, sizeof (int) * IW);

        /* some primitive error distribution + random dithering */

        for (y = 0; y < h; y++)
          {
            int er = 0, eg = 0, eb = 0;

            for (x = 0; x < w; x++)
              {
                int r, g, b;
                guchar *p = src + x * bpp + y * sstr;

                r = ((p[0] + er + Er[x]) * 7 + 128) / 255;
                g = ((p[1] + eg + Eg[x]) * 7 + 128) / 255;
                b = ((p[2] + eb + Eb[x]) * 3 + 128) / 255;

                r = r > 7 ? 7 : r < 0 ? 0 : r;
                g = g > 7 ? 7 : g < 0 ? 0 : g;
                b = b > 3 ? 3 : b < 0 ? 0 : b;

                er += p[0] - (r * 255 + 4) / 7;
                eg += p[1] - (g * 255 + 4) / 7;
                eb += p[2] - (b * 255 + 2) / 3;

                Er[x] = er / 2; er -= er / 2 + RAND % 7 - 3;
                Eg[x] = eg / 2; eg -= eg / 2 + RAND % 7 - 3;
                Eb[x] = eb / 2; eb -= eb / 2 + RAND % 7 - 3;

                *dst++ = r << 5 | g << 2 | b;
              }
          }
}
        OUTPUT:
        RETVAL

SV *
make_histogram (SV *ar)
        CODE:
{
        int i;
        AV *av, *result;

        if (!SvROK (ar) || SvTYPE (SvRV (ar)) != SVt_PVAV)
          croak ("Not an array ref as first argument to make_histogram");

        av = (AV *) SvRV (ar);
        result = newAV ();

        for (i = 0; i <= av_len (av); ++i)
          {
            int bigst = 1;
            int j = 0;
            SV *sv = *av_fetch (av, i, 1);
            STRLEN len;
            char *buf = SvPVbyte (sv, len);
            int tmphist[256];
            char *hist;

            SV *histsv = newSV (257);//("", 0);
            sv_upgrade (histsv, SVt_PV);
            SvCUR_set (histsv, 256);
            hist = SvPV_nolen (histsv);

            Zero (tmphist, 256, int);

            while (len--)
              ++tmphist[*buf++];

            for (j = 0; j < 256; ++j)
              if (tmphist[j] > bigst)
                bigst = tmphist[j];
            
            for (j = 0; j < 256; ++j)
              hist[j] = tmphist[j] * 255 / bigst;

            av_push (result, histsv);
          }

        RETVAL = newRV_noinc ((SV *)result);
}
        OUTPUT:
        RETVAL


#############################################################################

MODULE = Gtk2::CV PACKAGE = Gtk2::CV::PostScript

void
dump_ascii85 (PerlIO *fp, GdkPixbuf *pb)
        CODE:
{
        int w = gdk_pixbuf_get_width  (pb);
        int h = gdk_pixbuf_get_height (pb);
        int x, y, i;
        guchar *dst;
        int bpp = gdk_pixbuf_get_n_channels (pb);
        guchar *src = gdk_pixbuf_get_pixels (pb);
        int sstr = gdk_pixbuf_get_rowstride (pb);

        a85_init ();

        for (y = 0; y < h; y++)
          for (x = 0; x < w; x++)
            for (i = 0; i < (bpp < 3 ? 1 : 3); i++)
              a85_push (fp, src [x * bpp + y * sstr + i]);

        a85_finish (fp);
}

void
dump_binary (PerlIO *fp, GdkPixbuf *pb)
        CODE:
{
        int w = gdk_pixbuf_get_width  (pb);
        int h = gdk_pixbuf_get_height (pb);
        int x, y, i;
        guchar *dst;
        int bpp = gdk_pixbuf_get_n_channels (pb);
        guchar *src = gdk_pixbuf_get_pixels (pb);
        int sstr = gdk_pixbuf_get_rowstride (pb);

        for (y = 0; y < h; y++)
          for (x = 0; x < w; x++)
            for (i = 0; i < (bpp < 3 ? 1 : 3); i++)
              PerlIO_putc (fp, src [x * bpp + y * sstr + i]);
}

#############################################################################

MODULE = Gtk2::CV PACKAGE = Gtk2::CV

SV *
pb_to_hv84 (GdkPixbuf *pb)
        CODE:
{
        int w = gdk_pixbuf_get_width  (pb);
        int h = gdk_pixbuf_get_height (pb);
        int x, y;
        guchar *dst;
        int bpp = gdk_pixbuf_get_n_channels (pb);
        guchar *src = gdk_pixbuf_get_pixels (pb);
        int sstr = gdk_pixbuf_get_rowstride (pb);

        RETVAL = newSV (6 * 8 * 12 / 8);
        SvPOK_only (RETVAL);
        SvCUR_set (RETVAL, 6 * 8 * 12 / 8);

        dst = SvPVX (RETVAL);

        /* some primitive error distribution + random dithering */

        for (y = 0; y < h; y++)
          {
            guchar *p = src + y * sstr;

            for (x = 0; x < w; x += 2)
              {
                unsigned int r, g, b, h, s, v, H, V1, V2;

                if (bpp == 3)
                  r = *p++, g = *p++, b = *p++;
                else if (bpp == 1)
                  r = g = b = *p++;
                else
                  abort ();

                rgb_to_hsv (r, g, b, &h, &s, &v);

                H = (h * 15 / 255) << 4;
                V1 = v;

                if (bpp == 3)
                  r = *p++, g = *p++, b = *p++;
                else if (bpp == 1)
                  r = g = b = *p++;
                else
                  abort ();

                rgb_to_hsv (r, g, b, &h, &s, &v);

                H |= h * 15 / 255;
                V2 = v;

                *dst++ = H;
                *dst++ = V1;
                *dst++ = V2;
              }
          }
}
        OUTPUT:
        RETVAL

SV *
hv84_to_av (unsigned char *hv84)
        CODE:
{
        int i = 72 / 3;
        AV *av = newAV ();

        RETVAL = (SV *)newRV_noinc ((SV *)av);
        while (i--)
          {
            int h  = *hv84++;
            int v1 = *hv84++;
            int v2 = *hv84++;

            av_push (av, newSViv (v1));
            av_push (av, newSViv ((h >> 4) * 255 / 15));
            av_push (av, newSViv (v2));
            av_push (av, newSViv ((h & 15) * 255 / 15));
          }
}
        OUTPUT:
        RETVAL


Revision:	1.10
Committed:	Tue Feb 8 10:34:19 2005 UTC (19 years, 3 months ago) by root
Branch:	MAIN
Changes since 1.9:	+50 -0 lines
Log Message:	histogram sort
#	User	Rev	Content
1	root	1.1	#include "EXTERN.h"
2			#include "perl.h"
3			#include "XSUB.h"
4
5	root	1.2	#include <gdk-pixbuf/gdk-pixbuf.h>
6
7			#include <gperl.h>
8			#include <gtk2perl.h>
9
10	root	1.5	#define IW 80
11
12			#define RAND (seed = (seed + 7141) * 54773 % 134456)
13
14	root	1.7	#define LINELENGTH 240
15
16	root	1.6	#define ELLIPSIS "\xe2\x80\xa6"
17
18	root	1.4	static guint32 a85_val;
19			static guint a85_cnt;
20	root	1.7	static guchar a85_buf[LINELENGTH], *a85_ptr;
21	root	1.4
22			static void
23			a85_init (void)
24			{
25			a85_cnt = 4;
26			a85_ptr = a85_buf;
27			}
28
29			static void
30			a85_push (PerlIO *fp, guchar c)
31			{
32			a85_val = a85_val << 8 \| c;
33
34			if (!--a85_cnt)
35			{
36			a85_cnt = 4;
37			if (a85_val)
38			{
39			a85_ptr[4] = (a85_val % 85) + 33; a85_val /= 85;
40			a85_ptr[3] = (a85_val % 85) + 33; a85_val /= 85;
41			a85_ptr[2] = (a85_val % 85) + 33; a85_val /= 85;
42			a85_ptr[1] = (a85_val % 85) + 33; a85_val /= 85;
43			a85_ptr[0] = (a85_val ) + 33;
44
45			a85_ptr += 5;
46			}
47			else
48			*a85_ptr++ = 'z';
49
50			if (a85_ptr >= a85_buf + sizeof (a85_buf) - 7)
51			{
52			*a85_ptr++ = '\n';
53			PerlIO_write (fp, a85_buf, a85_ptr - a85_buf);
54			a85_ptr = a85_buf;
55			}
56			}
57
58			}
59
60	root	1.8	static void
61	root	1.4	a85_finish (PerlIO *fp)
62			{
63			while (a85_cnt != 4)
64			a85_push (fp, 0);
65
66			*a85_ptr++ = '~'; // probably buggy end-marker
67			*a85_ptr++ = '>'; // probably buggy end-marker
68			*a85_ptr++ = '\n';
69
70			PerlIO_write (fp, a85_buf, a85_ptr - a85_buf);
71			}
72
73	root	1.8	static void
74			rgb_to_hsv (unsigned int r, unsigned int g, unsigned int b,
75			unsigned int h, unsigned int s, unsigned int *v)
76			{
77			unsigned int mx = r; if (g > mx) mx = g; if (b > mx) mx = b;
78			unsigned int mn = r; if (g < mn) mn = g; if (b < mn) mn = b;
79			unsigned int delta = mx - mn;
80
81			*v = mx;
82
83			s = mx ? delta 255 / mx : 0;
84
85			if (delta == 0)
86			*h = 0;
87			else
88			{
89			if (r == mx)
90			h = ((int)g - (int)b) 255 / (int)(delta * 3);
91			else if (g == mx)
92			h = ((int)b - (int)r) 255 / (int)(delta * 3) + 52;
93			else if (b == mx)
94			h = ((int)r - (int)g) 255 / (int)(delta * 3) + 103;
95
96			*h &= 255;
97			}
98			}
99
100	root	1.6	/////////////////////////////////////////////////////////////////////////////
101
102	root	1.9	MODULE = Gtk2::CV PACKAGE = Gtk2::CV
103	root	1.1
104			PROTOTYPES: ENABLE
105	root	1.2
106	root	1.3	GdkPixbuf_noinc *
107	root	1.2	transpose (GdkPixbuf *pb)
108			CODE:
109			{
110			int w = gdk_pixbuf_get_width (pb);
111			int h = gdk_pixbuf_get_height (pb);
112	root	1.7	int bpp = gdk_pixbuf_get_n_channels (pb);
113	root	1.2	int x, y, i;
114			guchar src = gdk_pixbuf_get_pixels (pb), dst;
115			int sstr = gdk_pixbuf_get_rowstride (pb), dstr;
116
117			RETVAL = gdk_pixbuf_new (GDK_COLORSPACE_RGB, bpp == 4, 8, h, w);
118
119			dst = gdk_pixbuf_get_pixels (RETVAL);
120			dstr = gdk_pixbuf_get_rowstride (RETVAL);
121
122	root	1.3	for (y = 0; y < h; y++)
123			for (x = 0; x < w; x++)
124	root	1.2	for (i = 0; i < bpp; i++)
125			dst[y * bpp + x * dstr + i] = src[x * bpp + y * sstr + i];
126			}
127			OUTPUT:
128			RETVAL
129
130	root	1.3	GdkPixbuf_noinc *
131	root	1.2	flop (GdkPixbuf *pb)
132			CODE:
133			{
134			int w = gdk_pixbuf_get_width (pb);
135			int h = gdk_pixbuf_get_height (pb);
136	root	1.7	int bpp = gdk_pixbuf_get_n_channels (pb);
137	root	1.2	int x, y, i;
138			guchar src = gdk_pixbuf_get_pixels (pb), dst;
139			int sstr = gdk_pixbuf_get_rowstride (pb), dstr;
140
141			RETVAL = gdk_pixbuf_new (GDK_COLORSPACE_RGB, bpp == 4, 8, w, h);
142
143			dst = gdk_pixbuf_get_pixels (RETVAL);
144			dstr = gdk_pixbuf_get_rowstride (RETVAL);
145
146	root	1.3	for (y = 0; y < h; y++)
147			for (x = 0; x < w; x++)
148	root	1.2	for (i = 0; i < bpp; i++)
149	root	1.4	dst[(w - 1 - x) * bpp + y * dstr + i] = src[x * bpp + y * sstr + i];
150	root	1.2	}
151			OUTPUT:
152			RETVAL
153
154	root	1.6	#############################################################################
155
156	root	1.2	MODULE = Gtk2::CV PACKAGE = Gtk2::CV::Schnauzer
157
158	root	1.3	GdkPixbuf_noinc *
159	root	1.2	p7_to_pb (int w, int h, guchar *src)
160			CODE:
161			{
162			int x, y;
163			guchar dst, d;
164			int dstr;
165
166			RETVAL = gdk_pixbuf_new (GDK_COLORSPACE_RGB, 0, 8, w, h);
167			dst = gdk_pixbuf_get_pixels (RETVAL);
168			dstr = gdk_pixbuf_get_rowstride (RETVAL);
169
170			for (y = 0; y < h; y++)
171			for (d = dst + y * dstr, x = 0; x < w; x++)
172			{
173	root	1.3	d++ = (((src >> 5) & 7) * 255 + 4) / 7;
174			d++ = (((src >> 2) & 7) * 255 + 4) / 7;
175			d++ = (((src >> 0) & 3) * 255 + 2) / 3;
176	root	1.2
177			src++;
178			}
179	root	1.3	}
180			OUTPUT:
181			RETVAL
182
183			SV *
184			pb_to_p7 (GdkPixbuf *pb)
185			CODE:
186			{
187			int w = gdk_pixbuf_get_width (pb);
188			int h = gdk_pixbuf_get_height (pb);
189			int x, y;
190			guchar *dst;
191	root	1.7	int bpp = gdk_pixbuf_get_n_channels (pb);
192	root	1.3	guchar *src = gdk_pixbuf_get_pixels (pb);
193			int sstr = gdk_pixbuf_get_rowstride (pb);
194	root	1.5	int Er[IW], Eg[IW], Eb[IW];
195			int seed = 77;
196	root	1.3
197			RETVAL = newSV (w * h);
198			SvPOK_only (RETVAL);
199			SvCUR_set (RETVAL, w * h);
200
201			dst = SvPVX (RETVAL);
202
203	root	1.5	memset (Er, 0, sizeof (int) * IW);
204			memset (Eg, 0, sizeof (int) * IW);
205			memset (Eb, 0, sizeof (int) * IW);
206
207			/* some primitive error distribution + random dithering */
208
209	root	1.3	for (y = 0; y < h; y++)
210			{
211			int er = 0, eg = 0, eb = 0;
212
213			for (x = 0; x < w; x++)
214			{
215			int r, g, b;
216			guchar p = src + x bpp + y * sstr;
217
218	root	1.5	r = ((p[0] + er + Er[x]) * 7 + 128) / 255;
219			g = ((p[1] + eg + Eg[x]) * 7 + 128) / 255;
220			b = ((p[2] + eb + Eb[x]) * 3 + 128) / 255;
221	root	1.3
222			r = r > 7 ? 7 : r < 0 ? 0 : r;
223			g = g > 7 ? 7 : g < 0 ? 0 : g;
224			b = b > 3 ? 3 : b < 0 ? 0 : b;
225
226			er += p[0] - (r * 255 + 4) / 7;
227			eg += p[1] - (g * 255 + 4) / 7;
228			eb += p[2] - (b * 255 + 2) / 3;
229	root	1.5
230			Er[x] = er / 2; er -= er / 2 + RAND % 7 - 3;
231			Eg[x] = eg / 2; eg -= eg / 2 + RAND % 7 - 3;
232			Eb[x] = eb / 2; eb -= eb / 2 + RAND % 7 - 3;
233	root	1.3
234			*dst++ = r << 5 \| g << 2 \| b;
235			}
236			}
237	root	1.2	}
238			OUTPUT:
239			RETVAL
240	root	1.6
241	root	1.10	SV *
242			make_histogram (SV *ar)
243			CODE:
244			{
245			int i;
246			AV av, result;
247
248			if (!SvROK (ar) \|\| SvTYPE (SvRV (ar)) != SVt_PVAV)
249			croak ("Not an array ref as first argument to make_histogram");
250
251			av = (AV *) SvRV (ar);
252			result = newAV ();
253
254			for (i = 0; i <= av_len (av); ++i)
255			{
256			int bigst = 1;
257			int j = 0;
258			SV sv = av_fetch (av, i, 1);
259			STRLEN len;
260			char *buf = SvPVbyte (sv, len);
261			int tmphist[256];
262			char *hist;
263
264			SV *histsv = newSV (257);//("", 0);
265			sv_upgrade (histsv, SVt_PV);
266			SvCUR_set (histsv, 256);
267			hist = SvPV_nolen (histsv);
268
269			Zero (tmphist, 256, int);
270
271			while (len--)
272			++tmphist[*buf++];
273
274			for (j = 0; j < 256; ++j)
275			if (tmphist[j] > bigst)
276			bigst = tmphist[j];
277
278			for (j = 0; j < 256; ++j)
279			hist[j] = tmphist[j] * 255 / bigst;
280
281			av_push (result, histsv);
282			}
283
284			RETVAL = newRV_noinc ((SV *)result);
285			}
286			OUTPUT:
287			RETVAL
288
289
290
291	root	1.6	#############################################################################
292	root	1.4
293			MODULE = Gtk2::CV PACKAGE = Gtk2::CV::PostScript
294
295			void
296	root	1.7	dump_ascii85 (PerlIO fp, GdkPixbuf pb)
297	root	1.4	CODE:
298			{
299			int w = gdk_pixbuf_get_width (pb);
300			int h = gdk_pixbuf_get_height (pb);
301			int x, y, i;
302			guchar *dst;
303	root	1.7	int bpp = gdk_pixbuf_get_n_channels (pb);
304	root	1.4	guchar *src = gdk_pixbuf_get_pixels (pb);
305			int sstr = gdk_pixbuf_get_rowstride (pb);
306
307			a85_init ();
308
309			for (y = 0; y < h; y++)
310			for (x = 0; x < w; x++)
311	root	1.7	for (i = 0; i < (bpp < 3 ? 1 : 3); i++)
312	root	1.4	a85_push (fp, src [x * bpp + y * sstr + i]);
313
314			a85_finish (fp);
315	root	1.7	}
316
317			void
318			dump_binary (PerlIO fp, GdkPixbuf pb)
319			CODE:
320			{
321			int w = gdk_pixbuf_get_width (pb);
322			int h = gdk_pixbuf_get_height (pb);
323			int x, y, i;
324			guchar *dst;
325			int bpp = gdk_pixbuf_get_n_channels (pb);
326			guchar *src = gdk_pixbuf_get_pixels (pb);
327			int sstr = gdk_pixbuf_get_rowstride (pb);
328
329			for (y = 0; y < h; y++)
330			for (x = 0; x < w; x++)
331			for (i = 0; i < (bpp < 3 ? 1 : 3); i++)
332			PerlIO_putc (fp, src [x * bpp + y * sstr + i]);
333	root	1.4	}
334	root	1.8
335			#############################################################################
336
337			MODULE = Gtk2::CV PACKAGE = Gtk2::CV
338
339			SV *
340			pb_to_hv84 (GdkPixbuf *pb)
341			CODE:
342			{
343			int w = gdk_pixbuf_get_width (pb);
344			int h = gdk_pixbuf_get_height (pb);
345			int x, y;
346			guchar *dst;
347			int bpp = gdk_pixbuf_get_n_channels (pb);
348			guchar *src = gdk_pixbuf_get_pixels (pb);
349			int sstr = gdk_pixbuf_get_rowstride (pb);
350
351			RETVAL = newSV (6 * 8 * 12 / 8);
352			SvPOK_only (RETVAL);
353			SvCUR_set (RETVAL, 6 * 8 * 12 / 8);
354
355			dst = SvPVX (RETVAL);
356
357			/* some primitive error distribution + random dithering */
358
359			for (y = 0; y < h; y++)
360			{
361			guchar p = src + y sstr;
362
363			for (x = 0; x < w; x += 2)
364			{
365			unsigned int r, g, b, h, s, v, H, V1, V2;
366
367			if (bpp == 3)
368			r = p++, g = p++, b = *p++;
369			else if (bpp == 1)
370			r = g = b = *p++;
371			else
372			abort ();
373
374			rgb_to_hsv (r, g, b, &h, &s, &v);
375
376			H = (h * 15 / 255) << 4;
377			V1 = v;
378
379			if (bpp == 3)
380			r = p++, g = p++, b = *p++;
381			else if (bpp == 1)
382			r = g = b = *p++;
383			else
384			abort ();
385
386			rgb_to_hsv (r, g, b, &h, &s, &v);
387
388			H \|= h * 15 / 255;
389			V2 = v;
390
391			*dst++ = H;
392			*dst++ = V1;
393			*dst++ = V2;
394			}
395			}
396			}
397			OUTPUT:
398			RETVAL
399	root	1.4
400	root	1.9	SV *
401			hv84_to_av (unsigned char *hv84)
402			CODE:
403			{
404			int i = 72 / 3;
405			AV *av = newAV ();
406
407			RETVAL = (SV )newRV_noinc ((SV )av);
408			while (i--)
409			{
410			int h = *hv84++;
411			int v1 = *hv84++;
412			int v2 = *hv84++;
413
414			av_push (av, newSViv (v1));
415			av_push (av, newSViv ((h >> 4) * 255 / 15));
416			av_push (av, newSViv (v2));
417			av_push (av, newSViv ((h & 15) * 255 / 15));
418			}
419			}
420			OUTPUT:
421			RETVAL
422	root	1.2
423	root	1.1
424