Changeset 716

Timestamp:

03/03/10 04:04:50 (2 years ago)

Author:

mosttw

Message:

Basic histogramming works

Location:

trunk/software/rb/vision

Files:

• _processing.c (modified) (7 diffs)
• makefile (modified) (1 diff)

trunk/software/rb/vision/_processing.c

@@ -25 +25 @@
 #include "_camera.h"
 
+// The following macros return pointers to pixels in 1- and 3-channel images, respectively.
+#define IMAGE_PIXEL_C1(image, x, y) ((guint8*) (image->imageData + image->widthStep * y + x))
+#define IMAGE_PIXEL_C3(image, x, y) ((guint8*) (image->imageData + image->widthStep * y + x * 3))
+
+
 static PyTypeObject *PyGObjectType = NULL;
 static PyTypeObject *IplImageObjectType = NULL;
@@ -85 +90 @@
                 int sobel_aperture = 5;
                 int blur_aperture = 3;
+                int hist_bins = 100;
+                // Histogram bins below these thresholds are zeroed.
+                int hist_s_low =  50;
+                int hist_v_low = 100;
+
+                inline int hist_bin(guint8 pixel_value) {
+                        return pixel_value * hist_bins / 255.0; 
+                }
 
                 // Calculate the "working" image size
@@ -99 +112 @@
                 CvMat *sobel;
                 IplImage *texture;
+                int *hist_h;
+                int *hist_s;
+                int *hist_v;
 
                 hsv_full   = cvCreateImage(cvSize(input->width, input->height), IPL_DEPTH_8U, 3);
@@ -107 +123 @@
                 texture    = cvCreateImage(cvSize(working_width, working_height), IPL_DEPTH_8U, 1);
                 output     = cvCreateImage(cvSize(working_width, working_height), IPL_DEPTH_8U, 3);
+                hist_h     = malloc(sizeof(int) * hist_bins); // TODO: Check this return value
+                hist_s     = malloc(sizeof(int) * hist_bins); // TODO: Check this return value
+                hist_v     = malloc(sizeof(int) * hist_bins); // TODO: Check this return value
 
                 // Colorspace conversion and scaling
@@ -112 +131 @@
                 cvSplit(hsv_full, NULL, NULL, v_full, NULL);
                 cvResize(hsv_full, hsv, CV_INTER_AREA);
+
+                // Create the output image
+                cvResize(input, output, CV_INTER_AREA);
 
                 // Calculate "texture" channel
@@ -119 +141 @@
                 cvSmooth(texture, texture, CV_BLUR, blur_aperture, 0, 0, 0);
 
+                // Calculate the location of the "safe region", which will be histogrammed in
+                // order to determine what the grass looks like.
+                int tl_x = working_width * 0.2;
+                int tl_y = working_height * 0.8;
+                int br_x = working_width - tl_x - 1;
+                int br_y = working_height - 1;
+
+                // Generate the ground histogram
+                for (int x = tl_x; x <= br_x; x++) {
+                        for (int y = tl_y; y <= br_y; y++) {
+                                guint8 *pixel = IMAGE_PIXEL_C3(hsv, x, y);
+                                hist_h[hist_bin(pixel[0])]++;
+                                hist_s[hist_bin(pixel[1])]++;
+                                hist_v[hist_bin(pixel[2])]++;
+                        }
+                }
+
+                // Low-pass filter the histograms
+                for (int i = 0; i < hist_bins; i++) {
+                        if (hist_s[i] < hist_s_low) hist_s[i] = 0;
+                        if (hist_v[i] < hist_v_low) hist_v[i] = 0;
+                }
+
+                for (int x = 0; x < working_width; x++) {
+                        for (int y = 0; y < working_height; y++) {
+                                guint8 *hsv_pixel = IMAGE_PIXEL_C3(hsv, x, y);
+                                guint8 *out_pixel = IMAGE_PIXEL_C3(output, x, y);
+                                if (hist_h[hist_bin(hsv_pixel[0])] &&
+                                                hist_s[hist_bin(hsv_pixel[1])] &&
+                                                hist_v[hist_bin(hsv_pixel[2])]) {
+                                        out_pixel[0] = 0;
+                                        out_pixel[1] = 255;
+                                        out_pixel[2] = 0;
+                                }
+                        }
+                }
+
+
                 // Create output image
-                cvCvtColor(texture, output, CV_GRAY2BGR);
+                //cvCvtColor(texture, output, CV_GRAY2BGR);
         
                 cvReleaseImage(&hsv_full);
@@ -128 +188 @@
                 cvReleaseMat(&sobel);
                 cvReleaseImage(&texture);
+                free(hist_h);
+                free(hist_s);
+                free(hist_v);
         Py_END_ALLOW_THREADS
 

trunk/software/rb/vision/makefile

@@ -1 @@
-CFLAGS   := -p -pg -g -Wall -Werror -Wno-unused -pedantic -fPIC --std=gnu99 -fgnu89-inline -O3 $(shell pkg-config --cflags opencv gsl glib-2.0 gobject-2.0)
+CFLAGS   := -p -pg -g -Wall -Werror -Wno-unused -fPIC --std=gnu99 -fgnu89-inline -O3 $(shell pkg-config --cflags opencv gsl glib-2.0 gobject-2.0)
 #CFLAGS   := -p -pg -g -Wall -Werror -pedantic -fPIC -O3 $(shell pkg-config --cflags opencv gsl)
 CPPFLAGS := -p -pg -g -Wall -Werror -Wno-unused -pedantic -fPIC -O3 $(shell pkg-config --cflags opencv gsl)