zarray_t *apriltag_quad_thresh(apriltag_detector_t *td, image_u8_t *im)
{
////////////////////////////////////////////////////////
// step 1. threshold the image, creating the edge image.
int w = im->width, h = im->height, s = im->stride;
image_u8_t *threshim = threshold(td, im);
assert(threshim->stride == s);
image_u8_t *edgeim = image_u8_create(w, h);
if (1) {
image_u8_t *sumim = image_u8_create(w, h);
// apply a horizontal sum kernel of width 3
for (int y = 0; y < h; y++) {
for (int x = 1; x+1 < w; x++) {
sumim->buf[y*s + x] =
threshim->buf[y*s + x - 1] +
threshim->buf[y*s + x + 0] +
threshim->buf[y*s + x + 1];
}
}
timeprofile_stamp(td->tp, "sumim");
// deglitch
if (td->qtp.deglitch) {
for (int y = 1; y+1 < h; y++) {
for (int x = 1; x+1 < w; x++) {
// edge: black pixel next to white pixel
if (threshim->buf[y*s + x] == 0 &&
sumim->buf[y*s + x - s] + sumim->buf[y*s + x] + sumim->buf[y*s + x + s] == 8) {
threshim->buf[y*s + x] = 1;
sumim->buf[y*s + x - 1]++;
sumim->buf[y*s + x + 0]++;
sumim->buf[y*s + x + 1]++;
}
if (threshim->buf[y*s + x] == 1 &&
sumim->buf[y*s + x - s] + sumim->buf[y*s + x] + sumim->buf[y*s + x + s] == 1) {
threshim->buf[y*s + x] = 0;
sumim->buf[y*s + x - 1]--;
sumim->buf[y*s + x + 0]--;
sumim->buf[y*s + x + 1]--;
}
}
}
timeprofile_stamp(td->tp, "deglitch");
}
// apply a vertical sum kernel of width 3; check if any
// over-threshold pixels are adjacent to an under-threshold
// pixel.
//
// There are two types of edges: white pixels neighboring a
// black pixel, and black pixels neighboring a white pixel. We
// label these separately. (Values 0xc0 and 0x3f are picked
// such that they add to 255 (see below) and so that they can be
// viewed as pixel intensities for visualization purposes.)
//
// symmetry of detection. We don't want to use JUST "black
// near white" (or JUST "white near black"), because that
// biases the detection towards one side of the edge. This
// measurably reduces detection performance.
//
// On large tags, we could treat "neighbor" pixels the same
// way. But on very small tags, there may be other edges very
// near the tag edge. Since each of these edges is effectively
// two pixels thick (the white pixel near the black pixel, and
// the black pixel near the white pixel), it becomes likely
// that these two nearby edges will actually touch.
//
// A partial solution to this problem is to define edges to be
// adjacent white-near-black and black-near-white pixels.
//
for (int y = 1; y+1 < h; y++) {
for (int x = 1; x+1 < w; x++) {
if (threshim->buf[y*s + x] == 0) {
// edge: black pixel next to white pixel
if (sumim->buf[y*s + x - s] + sumim->buf[y*s + x] + sumim->buf[y*s + x + s] > 0)
edgeim->buf[y*s + x] = 0xc0;
} else {
// edge: white pixel next to black pixel when both
// edge types are on, we get less bias towards one
// side of the edge.
if (sumim->buf[y*s + x - s] + sumim->buf[y*s + x] + sumim->buf[y*s + x + s] < 9)
edgeim->buf[y*s + x] = 0x3f;
}
}
}
if (td->debug) {
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
threshim->buf[y*s + x] *= 255;
}
}
image_u8_write_pnm(threshim, "debug_threshold.pnm");
image_u8_write_pnm(edgeim, "debug_edge.pnm");
// image_u8_destroy(edgeim2);
}
image_u8_destroy(threshim);
image_u8_destroy(sumim);
}
timeprofile_stamp(td->tp, "edges");
////////////////////////////////////////////////////////
// step 2. find connected components.
unionfind_t *uf = unionfind_create(w * h);
for (int y = 1; y < h - 1; y++) {
for (int x = 1; x < w -1; x++) {
uint8_t v = edgeim->buf[y*s + x];
if (v==0)
continue;
// (dx,dy) pairs for 8 connectivity:
// (REFERENCE) (1, 0)
// (-1, 1) (0, 1) (1, 1)
//
// i.e., the minimum value of dx should be:
// y=0: 1
// y=1: -1
for (int dy = 0; dy <= 1; dy++) {
for (int dx = 1-2*dy; dx <= 1; dx++) {
if (edgeim->buf[(y+dy)*s + (x+dx)] == v) {
unionfind_connect(uf, y*w + x, (y+dy)*w + x + dx);
}
}
}
}
}
timeprofile_stamp(td->tp, "unionfind");
zhash_t *clustermap = zhash_create(sizeof(uint64_t), sizeof(zarray_t*),
zhash_uint64_hash, zhash_uint64_equals);
for (int y = 1; y < h-1; y++) {
for (int x = 1; x < w-1; x++) {
uint8_t v0 = edgeim->buf[y*s + x];
if (v0 == 0)
continue;
uint64_t rep0 = unionfind_get_representative(uf, y*w + x);
// 8 connectivity. (4 neighbors to check).
// for (int dy = 0; dy <= 1; dy++) {
// for (int dx = 1-2*dy; dx <= 1; dx++) {
// 4 connectivity. (2 neighbors to check)
for (int n = 1; n <= 2; n++) {
int dy = n & 1;
int dx = (n & 2) >> 1;
uint8_t v1 = edgeim->buf[(y+dy)*s + x + dx];
if (v0 + v1 != 255)
continue;
uint64_t rep1 = unionfind_get_representative(uf, (y+dy)*w + x+dx);
uint64_t clusterid;
if (rep0 < rep1)
clusterid = (rep1 << 32) + rep0;
else
clusterid = (rep0 << 32) + rep1;
zarray_t *cluster = NULL;
if (!zhash_get(clustermap, &clusterid, &cluster)) {
cluster = zarray_create(sizeof(struct pt));
zhash_put(clustermap, &clusterid, &cluster, NULL, NULL);
}
// NB: We will add some points multiple times to a
// given cluster. I don't know an efficient way to
// avoid that here; we remove them later on when we
// sort points by pt_compare_theta.
if (1) {
struct pt p = { .x = x, .y = y};
zarray_add(cluster, &p);
}
if (1) {
struct pt p = { .x = x+dx, .y = y+dy};
zarray_add(cluster, &p);
}
}
}
}
// make segmentation image.
if (td->debug) {
image_u8_t *d = image_u8_create(w, h);
assert(d->stride == s);
uint8_t *colors = (uint8_t*) calloc(w*h, 1);
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
uint32_t v = unionfind_get_representative(uf, y*w+x);
uint32_t sz = unionfind_get_set_size(uf, y*w+x);
if (sz < td->qtp.min_cluster_pixels)
continue;
uint8_t color = colors[v];
if (color == 0) {
const int bias = 20;
color = bias + (random() % (255-bias));
colors[v] = color;
}
float mix = 0.7;
mix = 1.0;
d->buf[y*d->stride + x] = mix*color + (1-mix)*im->buf[y*im->stride + x];
}
}
free(colors);
image_u8_write_pnm(d, "debug_segmentation.pnm");
image_u8_destroy(d);
}
timeprofile_stamp(td->tp, "make clusters");
////////////////////////////////////////////////////////
// step 3. process each connected component.
zarray_t *clusters = zhash_values(clustermap);
zhash_destroy(clustermap);
zarray_t *quads = zarray_create(sizeof(struct quad));
int sz = zarray_size(clusters);
int chunksize = 1 + sz / (APRILTAG_TASKS_PER_THREAD_TARGET * td->nthreads);
struct quad_task tasks[sz / chunksize + 1];
int ntasks = 0;
for (int i = 0; i < sz; i += chunksize) {
tasks[ntasks].td = td;
tasks[ntasks].cidx0 = i;
tasks[ntasks].cidx1 = imin(sz, i + chunksize);
tasks[ntasks].h = h;
tasks[ntasks].w = w;
tasks[ntasks].quads = quads;
tasks[ntasks].clusters = clusters;
tasks[ntasks].im = im;
workerpool_add_task(td->wp, do_quad_task, &tasks[ntasks]);
ntasks++;
}
workerpool_run(td->wp);
timeprofile_stamp(td->tp, "fit quads to clusters");
if (td->debug) {
FILE *f = fopen("debug_lines.ps", "w");
fprintf(f, "%%!PS\n\n");
image_u8_t *im2 = image_u8_copy(im);
image_u8_darken(im2);
image_u8_darken(im2);
// assume letter, which is 612x792 points.
double scale = fmin(612.0/im->width, 792.0/im2->height);
fprintf(f, "%.15f %.15f scale\n", scale, scale);
fprintf(f, "0 %d translate\n", im2->height);
fprintf(f, "1 -1 scale\n");
postscript_image(f, im);
for (int i = 0; i < zarray_size(quads); i++) {
struct quad *q;
zarray_get_volatile(quads, i, &q);
float rgb[3];
int bias = 100;
for (int i = 0; i < 3; i++)
rgb[i] = bias + (random() % (255-bias));
fprintf(f, "%f %f %f setrgbcolor\n", rgb[0]/255.0f, rgb[1]/255.0f, rgb[2]/255.0f);
fprintf(f, "%.15f %.15f moveto %.15f %.15f lineto %.15f %.15f lineto %.15f %.15f lineto %.15f %.15f lineto stroke\n",
q->p[0][0], q->p[0][1],
q->p[1][0], q->p[1][1],
q->p[2][0], q->p[2][1],
q->p[3][0], q->p[3][1],
q->p[0][0], q->p[0][1]);
}
fclose(f);
}
// printf(" %d %d %d %d\n", indices[0], indices[1], indices[2], indices[3]);
/*
if (td->debug) {
for (int i = 0; i < 4; i++) {
int i0 = indices[i];
int i1 = indices[(i+1)&3];
if (i1 < i0)
i1 += zarray_size(cluster);
for (int j = i0; j <= i1; j++) {
struct pt *p;
zarray_get_volatile(cluster, j % zarray_size(cluster), &p);
edgeim->buf[p->y*edgeim->stride + p->x] = 30+64*i;
}
}
} */
unionfind_destroy(uf);
for (int i = 0; i < zarray_size(clusters); i++) {
zarray_t *cluster;
zarray_get(clusters, i, &cluster);
zarray_destroy(cluster);
}
zarray_destroy(clusters);
image_u8_destroy(edgeim);
return quads;
}
static void update_view(vx_gtk_buffer_manager_t * gtk)
{
// This order of these two mutex locks should prevent deadloc
// even if a user sends op codes while the user holds the GDK mutex
gdk_threads_enter();
pthread_mutex_lock(>k->mutex);
// Clear XXX Double buffered?
GList * children = gtk_container_get_children(GTK_CONTAINER(gtk->window));
for(GList * iter = children; iter != NULL; iter = g_list_next(iter))
gtk_widget_destroy(GTK_WIDGET(iter->data));
g_list_free(children);
// Rebuild from scratch
GtkWidget * box = gtk_vbox_new(0, 10);
GtkWidget * widget = NULL;
zarray_t *layers = zhash_values(gtk->layers); // contents: layer_info_t*
zarray_sort(layers, layer_info_compare);
for (int lidx = 0; lidx < zarray_size(layers); lidx++) {
layer_info_t *linfo = NULL;
zarray_get(layers, lidx, &linfo);
// Draw the layer name:
widget = gtk_label_new("");
char * text = sprintf_alloc("<b>Layer %d</b>", linfo->layer_id);
gtk_label_set_markup(GTK_LABEL(widget), text);
free(text);
//gtk_container_add(GTK_CONTAINER(box), widget);
gtk_box_pack_start(GTK_BOX(box), widget, FALSE, FALSE, 0);
// Make a checkbox for each buffer
zarray_t *buffers = zhash_values(linfo->buffers); // contents: buffer_info_t*
zarray_sort(buffers, buffer_info_compare);
for (int i = 0; i < zarray_size(buffers); i++) {
buffer_info_t * buffer = NULL;
zarray_get(buffers, i, &buffer);
assert(buffer != NULL);
widget = gtk_check_button_new_with_label(buffer->name);
gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(widget), buffer->enabled);
g_signal_connect (G_OBJECT(widget), "toggled",
G_CALLBACK (buffer_checkbox_changed), buffer);
//gtk_container_add(GTK_CONTAINER(box), widget);
gtk_box_pack_start(GTK_BOX(box), widget, FALSE, FALSE, 0);
}
zarray_destroy(buffers);
}
gtk_container_add(GTK_CONTAINER(gtk->window), box);
gtk_widget_show_all(box);
zarray_destroy(layers);
pthread_mutex_unlock(>k->mutex);
gdk_threads_leave();
}
void hsv_find_balls_blob_detector(image_u32_t* im, frame_t frame, metrics_t met, zarray_t* blobs_out)
{
assert(frame.xy0.x < frame.xy1.x && frame.xy0.y < frame.xy1.y);
assert(frame.xy0.x >= 0 && frame.xy0.y >= 0 && frame.xy1.x < im->width && frame.xy1.y < im->height);
assert(frame.ex0.x < frame.ex1.x && frame.ex0.y < frame.ex1.y);
assert(frame.ex0.x >= 0 && frame.ex0.y >= 0 && frame.ex1.x < im->width && frame.ex1.y < im->height);
// Int to node
zhash_t* node_map = zhash_create(sizeof(uint32_t), sizeof(node_t*),
zhash_uint32_hash, zhash_uint32_equals);
for(int i = frame.xy0.y; i < frame.xy1.y; i++) {
for(int j = frame.xy0.x; j < frame.xy1.x; j++) {
if((i < frame.ex0.y || i > frame.ex1.y) || (j < frame.ex0.x || j > frame.ex1.x)) {
uint32_t idx_im = i * im->stride + j; // Indframe.ex relative to image
// Pixel color data
uint32_t abgr = im->buf[idx_im];
hsv_t hsv = {0,0,0};
rgb_to_hsv(abgr, &hsv);
hsv_t error = {fabs(hsv.hue - met.hsv.hue),
fabs(hsv.sat - met.hsv.sat),
fabs(hsv.val - met.hsv.val)};
// 'Acceptable'
if((error.hue < met.error.hue) &&
(error.sat < met.error.sat) &&
(error.val < met.error.val))
{
// Create new node, set itself up as a parent
node_t* n = calloc(1, sizeof(node_t));
n->id = idx_im;
n->parent_id = idx_im;
n->parent_node = n;
n->num_children = 0;
node_t* tmp_node;
uint32_t tmp_idx;
// Add node to node map
if(zhash_put(node_map, &idx_im, &n, &tmp_idx, &tmp_node)==1)
{
assert(0);
}
//Check if apart of another blob, or starting a new blob
// if apart of another, point to the parent, if a new blob, point to self
//Check neighbours
if(!met.lines) { // only check this if don't want lines for tape detection
if(j > frame.xy0.x) {
tmp_idx = idx_im - 1; // is Left neighbour similar color
if(zhash_get(node_map, &tmp_idx, &tmp_node) == 1) {
node_t* neighbour = tmp_node;
connect(n, neighbour);
}
}
}
if(i > frame.xy0.y) {
tmp_idx = idx_im - im->stride; // is Bottom neighbor similar color
if(tmp_idx > 0 && zhash_get(node_map, &tmp_idx, &tmp_node) == 1) {
node_t* neighbour = tmp_node;
connect(neighbour,n);
}
}
}
}
}
}
//count number of children for each parent, go through node_map
// if a node is not a parent, add 1 to it's parent->num_children and delete from hash
// if is a parent do nothing
zarray_t* vals = zhash_values(node_map);
for(int i = 0; i < zarray_size(vals); i++) {
node_t* node;
zarray_get(vals, i, &node);
resolve_r(node);
if(node->parent_id != node->id) {
node->parent_node->num_children++;
// key should exist, if it doesn't find out why
assert(zhash_remove(node_map, &node->id, NULL, NULL));
}
}
// search parent only hash and add to blobs out conditionally
vals = zhash_values(node_map);
for(int i = 0; i < zarray_size(vals); i++) {
node_t* node;
zarray_get(vals, i, &node);
if(node->num_children > met.min_size) {
loc_t pos;
pos.x = node->parent_id%im->stride;
pos.y = node->parent_id/im->stride;
zarray_add(blobs_out, &pos);
// printf("parent %d\n", node->id);
}
}
zarray_destroy(vals);
zhash_vmap_values(node_map, free);
zhash_destroy(node_map);
}
