4 * Author: Vladimir Nadvornik
5 * based on a patch by Uwe Ohse
7 * This software is released under the GNU General Public License (GNU GPL).
8 * Please read the included file COPYING for more information.
9 * This software comes with no warranty of any kind, use at your own risk!
13 #include "histogram.h"
17 *----------------------------------------------------------------------------
19 *----------------------------------------------------------------------------
23 Histogram *histogram_new()
27 histogram = g_new0(Histogram, 1);
28 histogram->histogram_chan = HCHAN_RGB;
29 histogram->histogram_logmode = 1;
34 void histogram_free(Histogram *histogram)
40 gint histogram_set_channel(Histogram *histogram, gint chan)
42 if (!histogram) return 0;
43 histogram->histogram_chan = chan;
47 gint histogram_get_channel(Histogram *histogram)
49 if (!histogram) return 0;
50 return histogram->histogram_chan;
53 gint histogram_set_mode(Histogram *histogram, gint mode)
55 if (!histogram) return 0;
56 histogram->histogram_logmode = mode;
60 gint histogram_get_mode(Histogram *histogram)
62 if (!histogram) return 0;
63 return histogram->histogram_logmode;
66 const gchar *histogram_label(Histogram *histogram)
69 if (!histogram) return NULL;
71 if (histogram->histogram_logmode)
72 switch (histogram->histogram_chan) {
73 case HCHAN_R: t1 = _("logarithmical histogram on red"); break;
74 case HCHAN_G: t1 = _("logarithmical histogram on green"); break;
75 case HCHAN_B: t1 = _("logarithmical histogram on blue"); break;
76 case HCHAN_VAL: t1 = _("logarithmical histogram on value"); break;
77 case HCHAN_RGB: t1 = _("logarithmical histogram on RGB"); break;
78 case HCHAN_MAX: t1 = _("logarithmical histogram on max value"); break;
81 switch (histogram->histogram_chan) {
82 case HCHAN_R: t1 = _("linear histogram on red"); break;
83 case HCHAN_G: t1 = _("linear histogram on green"); break;
84 case HCHAN_B: t1 = _("linear histogram on blue"); break;
85 case HCHAN_VAL: t1 = _("linear histogram on value"); break;
86 case HCHAN_RGB: t1 = _("linear histogram on RGB"); break;
87 case HCHAN_MAX: t1 = _("linear histogram on max value"); break;
92 gulong histogram_read(Histogram *histogram, GdkPixbuf *imgpixbuf)
94 gint w, h, i, j, srs, has_alpha;
97 if (!histogram) return 0;
99 w = gdk_pixbuf_get_width(imgpixbuf);
100 h = gdk_pixbuf_get_height(imgpixbuf);
101 srs = gdk_pixbuf_get_rowstride(imgpixbuf);
102 s_pix = gdk_pixbuf_get_pixels(imgpixbuf);
103 has_alpha = gdk_pixbuf_get_has_alpha(imgpixbuf);
105 for (i = 0; i < 256*4; i++) histogram->histmap[i] = 0;
107 for (i = 0; i < h; i++)
109 guchar *sp = s_pix + (i * srs); /* 8bit */
110 for (j = 0; j < w; j++)
112 histogram->histmap[sp[0]+0]++;
113 histogram->histmap[sp[1]+256]++;
114 histogram->histmap[sp[2]+512]++;
115 if (histogram->histogram_chan == HCHAN_MAX)
118 if (sp[1]>t) t = sp[1];
119 if (sp[2]>t) t = sp[2];
120 histogram->histmap[t+768]++;
123 histogram->histmap[768+(sp[0]+sp[1]+sp[2])/3]++;
133 int histogram_draw(Histogram *histogram, GdkPixbuf *pixbuf, gint x, gint y, gint width, gint height)
135 /* FIXME: use the coordinates correctly */
140 if (!histogram) return 0;
142 for (i=0; i<1024; i++) {
145 switch (histogram->histogram_chan)
147 case HCHAN_RGB: if ((i%4) != 3 ) flag = 1; break;
148 case HCHAN_R: if ((i%4) == 0) flag = 1; break;
149 case HCHAN_G: if ((i%4) == 1) flag = 1; break;
150 case HCHAN_B: if ((i%4) == 2) flag = 1; break;
151 case HCHAN_VAL: if ((i%4) == 3) flag = 1; break;
152 case HCHAN_MAX: if ((i%4) == 3) flag = 1; break;
154 if (flag && histogram->histmap[i] > max) max = histogram->histmap[i];
158 for (i=0; i<256; i++)
166 v[0] = histogram->histmap[i+0*256]; // r
167 v[1] = histogram->histmap[i+1*256]; // g
168 v[2] = histogram->histmap[i+2*256]; // b
169 v[3] = histogram->histmap[i+3*256]; // value, max
181 if (v[k] > v[max2]) max2 = k;
185 case HCHAN_R: rplus = r = 255; break;
186 case HCHAN_G: gplus = g = 255; break;
187 case HCHAN_B: bplus = b = 255; break;
190 switch(histogram->histogram_chan)
192 case HCHAN_MAX: r = 0; b = 0; g = 0; break;
193 case HCHAN_VAL: r = 0; b = 0; g = 0; break;
194 case HCHAN_R: g = 0; b = 0; break;
195 case HCHAN_G: r = 0; b = 0; break;
196 case HCHAN_B: r = 0; g = 0; break;
198 if (r == 255 && g == 255 && b == 255) {
208 else if (histogram->histogram_logmode)
209 pt = ((float)log(v[max2]))/logmax*255;
211 pt = ((float)v[max2])/max*255;
212 if (histogram->histogram_chan >= HCHAN_RGB
213 || max2 == histogram->histogram_chan)
214 pixbuf_draw_line(pixbuf,
215 0+5, height-255, 256, 256,
216 i+5, height, i+5, height-pt,