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"
15 #include "pixbuf_util.h"
20 *----------------------------------------------------------------------------
22 *----------------------------------------------------------------------------
26 Histogram *histogram_new()
30 histogram = g_new0(Histogram, 1);
31 histogram->histogram_chan = HCHAN_RGB;
32 histogram->histogram_logmode = 1;
37 void histogram_free(Histogram *histogram)
43 gint histogram_set_channel(Histogram *histogram, gint chan)
45 if (!histogram) return 0;
46 histogram->histogram_chan = chan;
50 gint histogram_get_channel(Histogram *histogram)
52 if (!histogram) return 0;
53 return histogram->histogram_chan;
56 gint histogram_set_mode(Histogram *histogram, gint mode)
58 if (!histogram) return 0;
59 histogram->histogram_logmode = mode;
63 gint histogram_get_mode(Histogram *histogram)
65 if (!histogram) return 0;
66 return histogram->histogram_logmode;
69 const gchar *histogram_label(Histogram *histogram)
72 if (!histogram) return NULL;
74 if (histogram->histogram_logmode)
75 switch (histogram->histogram_chan) {
76 case HCHAN_R: t1 = _("logarithmical histogram on red"); break;
77 case HCHAN_G: t1 = _("logarithmical histogram on green"); break;
78 case HCHAN_B: t1 = _("logarithmical histogram on blue"); break;
79 case HCHAN_VAL: t1 = _("logarithmical histogram on value"); break;
80 case HCHAN_RGB: t1 = _("logarithmical histogram on RGB"); break;
81 case HCHAN_MAX: t1 = _("logarithmical histogram on max value"); break;
84 switch (histogram->histogram_chan) {
85 case HCHAN_R: t1 = _("linear histogram on red"); break;
86 case HCHAN_G: t1 = _("linear histogram on green"); break;
87 case HCHAN_B: t1 = _("linear histogram on blue"); break;
88 case HCHAN_VAL: t1 = _("linear histogram on value"); break;
89 case HCHAN_RGB: t1 = _("linear histogram on RGB"); break;
90 case HCHAN_MAX: t1 = _("linear histogram on max value"); break;
95 gulong histogram_read(Histogram *histogram, GdkPixbuf *imgpixbuf)
97 gint w, h, i, j, srs, has_alpha;
100 if (!histogram) return 0;
102 w = gdk_pixbuf_get_width(imgpixbuf);
103 h = gdk_pixbuf_get_height(imgpixbuf);
104 srs = gdk_pixbuf_get_rowstride(imgpixbuf);
105 s_pix = gdk_pixbuf_get_pixels(imgpixbuf);
106 has_alpha = gdk_pixbuf_get_has_alpha(imgpixbuf);
108 for (i = 0; i < 256*4; i++) histogram->histmap[i] = 0;
110 for (i = 0; i < h; i++)
112 guchar *sp = s_pix + (i * srs); /* 8bit */
113 for (j = 0; j < w; j++)
115 histogram->histmap[sp[0]+0]++;
116 histogram->histmap[sp[1]+256]++;
117 histogram->histmap[sp[2]+512]++;
118 if (histogram->histogram_chan == HCHAN_MAX)
121 if (sp[1]>t) t = sp[1];
122 if (sp[2]>t) t = sp[2];
123 histogram->histmap[t+768]++;
126 histogram->histmap[768+(sp[0]+sp[1]+sp[2])/3]++;
136 gint histogram_draw(Histogram *histogram, GdkPixbuf *pixbuf, gint x, gint y, gint width, gint height)
138 /* FIXME: use the coordinates correctly */
143 if (!histogram) return 0;
145 for (i=0; i<1024; i++) {
148 switch (histogram->histogram_chan)
150 case HCHAN_RGB: if ((i%4) != 3 ) flag = 1; break;
151 case HCHAN_R: if ((i%4) == 0) flag = 1; break;
152 case HCHAN_G: if ((i%4) == 1) flag = 1; break;
153 case HCHAN_B: if ((i%4) == 2) flag = 1; break;
154 case HCHAN_VAL: if ((i%4) == 3) flag = 1; break;
155 case HCHAN_MAX: if ((i%4) == 3) flag = 1; break;
157 if (flag && histogram->histmap[i] > max) max = histogram->histmap[i];
161 for (i=0; i<256; i++)
169 v[0] = histogram->histmap[i+0*256]; // r
170 v[1] = histogram->histmap[i+1*256]; // g
171 v[2] = histogram->histmap[i+2*256]; // b
172 v[3] = histogram->histmap[i+3*256]; // value, max
184 if (v[k] > v[max2]) max2 = k;
188 case HCHAN_R: rplus = r = 255; break;
189 case HCHAN_G: gplus = g = 255; break;
190 case HCHAN_B: bplus = b = 255; break;
193 switch(histogram->histogram_chan)
195 case HCHAN_MAX: r = 0; b = 0; g = 0; break;
196 case HCHAN_VAL: r = 0; b = 0; g = 0; break;
197 case HCHAN_R: g = 0; b = 0; break;
198 case HCHAN_G: r = 0; b = 0; break;
199 case HCHAN_B: r = 0; g = 0; break;
201 if (r == 255 && g == 255 && b == 255) {
211 else if (histogram->histogram_logmode)
212 pt = ((float)log(v[max2]))/logmax*255;
214 pt = ((float)v[max2])/max*255;
215 if (histogram->histogram_chan >= HCHAN_RGB
216 || max2 == histogram->histogram_chan)
217 pixbuf_draw_line(pixbuf,
218 0+5, height-255, 256, 256,
219 i+5, height, i+5, height-pt,