potrace_bitmap_t *bitmapFromImage(const QImage &image,
int threshold)
{
// De momento no implementamos que la imagen no tenga alpha channel
// Q_ASSERT(image.hasAlphaChannel());
potrace_bitmap_t *bitmap = bm_new(image.width(), image.height());
int pi = 0;
for(int i = 0; i < image.byteCount(); i += 4)
{
int x = pi % image.width();
int y = pi / image.width();
int p;
if(image.hasAlphaChannel())
{
p = (image.bits()[i+3] > threshold)? 1 : 0;
}
else
{
p = (image.bits()[i] > threshold)? 0 : 1;
}
BM_PUT(bitmap, x, y, p);
++pi;
}
return bitmap;
}
int main() {
int x, y, i;
potrace_bitmap_t *bm;
potrace_param_t *param;
potrace_path_t *p;
potrace_state_t *st;
int n, *tag;
potrace_dpoint_t(*c)[3];
/* create a bitmap */
bm = bm_new(WIDTH, HEIGHT);
if (!bm) {
fprintf(stderr, "Error allocating bitmap: %s\n", strerror(errno));
return 1;
}
/* fill the bitmap with some pattern */
for (y = 0; y < HEIGHT; y++) {
for (x = 0; x < WIDTH; x++) {
BM_PUT(bm, x, y, ((x * x + y * y * y) % 10000 < 5000) ? 1 : 0);
}
}
/* set tracing parameters, starting from defaults */
param = potrace_param_default();
if (!param) {
fprintf(stderr, "Error allocating parameters: %s\n", strerror(errno));
return 1;
}
param->turdsize = 0;
/* trace the bitmap */
st = potrace_trace(param, bm);
if (!st || st->status != POTRACE_STATUS_OK) {
fprintf(stderr, "Error tracing bitmap: %s\n", strerror(errno));
return 1;
}
bm_free(bm);
/* output vector data, e.g. as a rudimentary EPS file */
printf("%%!PS-Adobe-3.0 EPSF-3.0\n");
printf("%%%%BoundingBox: 0 0 %d %d\n", WIDTH, HEIGHT);
printf("gsave\n");
/* draw each curve */
p = st->plist;
while (p != NULL) {
n = p->curve.n;
tag = p->curve.tag;
c = p->curve.c;
printf("%f %f moveto\n", c[n - 1][2].x, c[n - 1][2].y);
for (i = 0; i < n; i++) {
switch (tag[i]) {
case POTRACE_CORNER:
printf("%f %f lineto\n", c[i][1].x, c[i][1].y);
printf("%f %f lineto\n", c[i][2].x, c[i][2].y);
break;
case POTRACE_CURVETO:
printf("%f %f %f %f %f %f curveto\n", c[i][0].x, c[i][0].y, c[i][1].x, c[i][1].y,
c[i][2].x, c[i][2].y);
break;
}
}
/* at the end of a group of a positive path and its negative
children, fill. */
if (p->next == NULL || p->next->sign == '+') {
printf("0 setgray fill\n");
}
p = p->next;
}
printf("grestore\n");
printf("%%EOF\n");
potrace_state_free(st);
potrace_param_free(param);
return 0;
}
JNIEXPORT jobject JNICALL Java_com_jiangpeng_android_antrace_Utils_traceImage(JNIEnv* env, jobject thiz, jobject bitmap)
{
AndroidBitmapInfo info;
int ret = 0;
void* src_pixels = 0;
if ((ret = AndroidBitmap_getInfo(env, bitmap, &info)) < 0) {
return NULL;
}
if (info.format != ANDROID_BITMAP_FORMAT_RGBA_8888) {
return NULL;
}
if ((ret = AndroidBitmap_lockPixels(env, bitmap, &src_pixels)) < 0) {
return NULL;
}
potrace_param_t* param_t = potrace_param_default();
param_t->turdsize = 15;
param_t->opttolerance = 0.8;
potrace_bitmap_t* bmp_t = bm_new(info.width, info.height);
//memcpy(bmp_t->map, src_pixels, bmp_t->dy * bmp_t->h * BM_WORDSIZE);
const int kShiftBits = 20;
const int32_t kRedRatio = static_cast<int32_t>((1 << kShiftBits) * 0.21f);
const int32_t kGreenRatio = static_cast<int32_t>((1 << kShiftBits) * 0.71f);
const int32_t kBlueRatio = static_cast<int32_t>((1 << kShiftBits) * 0.07f);
for (uint32_t scan_line = 0; scan_line < info.height; scan_line++) {
pixel32_t* src = reinterpret_cast<pixel32_t*>(src_pixels);
pixel32_t* src_line_end = src + info.width;
int x = 0;
while (src < src_line_end) {
int32_t src_red = src->rgba8[0];
int32_t src_green = src->rgba8[1];
int32_t src_blue = src->rgba8[2];
int32_t src_alpha = src->rgba8[3];
int32_t dst_color = (kRedRatio * src_red + kGreenRatio * src_green +
kBlueRatio * src_blue) >> kShiftBits;
if (dst_color > 128) {
BM_PUT(bmp_t, x, info.height - 1 - scan_line, 1);
}
else
{
BM_PUT(bmp_t, x, info.height - 1 - scan_line, 0);
}
src++;
++x;
}
src_pixels = reinterpret_cast<char*>(src_pixels) + info.stride;
}
if(s_state != NULL)
{
potrace_state_free(s_state);
s_state = NULL;
}
s_state = potrace_trace(param_t, bmp_t);
potrace_param_free(param_t);
bm_free(bmp_t);
AndroidBitmap_unlockPixels(env, bitmap);
if (!s_state || s_state->status != POTRACE_STATUS_OK) {
return NULL;
}
potrace_path_t* start = s_state->plist;
jobject prev = 0;
jclass cls = env->FindClass("com/jiangpeng/android/antrace/Objects/path");
jobject retPath = 0;
for(potrace_path_t* n = start; n != 0; n = n->next)
{
jobject path = createPath(env, n);
if(retPath == 0)
{
retPath = path;
}
if(prev != 0)
{
jfieldID fid = env->GetFieldID(cls, "next", "Lcom/jiangpeng/android/antrace/Objects/path;");
env->SetObjectField(prev, fid, path);
env->DeleteLocalRef(prev);
}
prev = path;
}
env->DeleteLocalRef(cls);
return retPath;
}
