void
JB2Dict::JB2Codec::Decode::code_absolute_mark_size(GBitmap &bm, int border)
{
int xsize=CodeNum(0, BIGPOSITIVE, abs_size_x);
int ysize=CodeNum(0, BIGPOSITIVE, abs_size_y);
if ((xsize!=(unsigned short)xsize) || (ysize!=(unsigned short)ysize))
G_THROW( ERR_MSG("JB2Image.bad_number") );
bm.init(ysize, xsize, border);
}
void
JB2Dict::JB2Codec::Decode::code_relative_mark_size(GBitmap &bm, int cw, int ch, int border)
{
int xdiff=CodeNum(BIGNEGATIVE, BIGPOSITIVE, rel_size_x);
int ydiff=CodeNum(BIGNEGATIVE, BIGPOSITIVE, rel_size_y);
int xsize = cw + xdiff;
int ysize = ch + ydiff;
if ((xsize!=(unsigned short)xsize) || (ysize!=(unsigned short)ysize))
G_THROW( ERR_MSG("JB2Image.bad_number") );
bm.init(ysize, xsize, border);
}
static void
maskedSubsample(const GPixmap* img,
const GBitmap *p_mask,
GPixmap& subsampled_image,
GBitmap& subsampled_mask,
int gridwidth, int inverted_mask,
int minpixels=1
)
{
const GPixmap& image= *img;
const GBitmap& mask = *p_mask;
int imageheight = image.rows();
int imagewidth = image.columns();
// compute the size of the resulting subsampled image
int subheight = imageheight/gridwidth;
if(imageheight%gridwidth)
subheight++;
int subwidth = imagewidth/gridwidth;
if(imagewidth%gridwidth)
subwidth++;
// set the sizes unless in incremental mode
subsampled_image.init(subheight, subwidth);
subsampled_mask.init(subheight, subwidth);
// go subsampling
int row, col; // row and col in the subsampled image
int posx, posxend, posy, posyend; // corresponding square in the original image
for(row=0, posy=0; row<subheight; row++, posy+=gridwidth)
{
GPixel* subsampled_image_row = subsampled_image[row]; // row row of subsampled image
unsigned char* subsampled_mask_row = subsampled_mask[row]; // row row of subsampled mask
posyend = posy+gridwidth;
if(posyend>imageheight)
posyend = imageheight;
for(col=0, posx=0; col<subwidth; col++, posx+=gridwidth)
{
posxend = posx+gridwidth;
if(posxend>imagewidth)
posxend = imagewidth;
int count = 0;
int r = 0;
int g = 0;
int b = 0;
for(int y=posy; y<posyend; y++)
{
const unsigned char* mask_y = mask[y]; // Row y of the mask
for(int x=posx; x<posxend; x++)
{
unsigned char masked = (inverted_mask ? !mask_y[x] :mask_y[x]);
if(!masked)
{
GPixel p = image[y][x];
r += p.r;
g += p.g;
b += p.b;
count ++;
}
}
}
/* minpixels pixels are enough to give the color */
/* so set it, and do not mask this point */
if(count >= minpixels)
{
GPixel p;
p.r = r/count;
p.g = g/count;
p.b = b/count;
subsampled_image_row[col] = p;
subsampled_mask_row[col] = 0;
}
else /* make it bright red and masked */
{
subsampled_image_row[col] = GPixel::RED;
subsampled_mask_row[col] = 1;
}
}
}
}
