void scan_image (const char *filename)
{
scanner.reset();
// normally scanner would reset associated decoder,
// but this debug program connects them manually
// (to make intermediate state more readily available)
// so decoder must also be reset manually
decoder.reset();
Magick::Image image;
image.read(filename);
string file = image.baseFilename();
size_t baseidx = file.rfind('/');
if(baseidx != string::npos)
file = file.substr(baseidx + 1, file.length() - baseidx - 1);
ofstream svg((file + ".svg").c_str());
unsigned inwidth = image.columns();
unsigned flush1 = inwidth / 32;
unsigned flush0 = 2;
unsigned width = inwidth + flush1 + flush0;
unsigned height = image.rows();
unsigned midy = (height + 1) / 2 + 2;
image.crop(Magick::Geometry(inwidth, 1, 0, midy));
image.size(Magick::Geometry(width, 1, 0, 0));
svg << "<?xml version='1.0'?>" << endl
<< "<!DOCTYPE svg PUBLIC '-//W3C//DTD SVG 1.1//EN'"
<< " 'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd'>" << endl
<< "<svg version='1.1' id='top'"
<< " width='10in' height='6in' preserveAspectRatio='xMinYMid slice'"
<< " overflow='visible' viewBox='0,0 " << width * 2 << ",384'"
<< " xmlns:xlink='http://www.w3.org/1999/xlink'"
<< " xmlns='http://www.w3.org/2000/svg'>" << endl
<< "<defs><style type='text/css'><![CDATA[" << endl
<< " * { stroke-linejoin: round; stroke-linecap: round;"
<< " stroke-width: .1; text-anchor: middle;"
<< " image-rendering: optimizeSpeed;"
<< " font-size: 6; font-weight: bold }" << endl
<< " path { fill: none }" << endl
<< " #zero { stroke: #00f }" << endl
<< " #edges { stroke: #f00 }" << endl
<< " #cur-edge { stroke: #f44 }" << endl
<< " #raw { stroke: orange }" << endl
<< " #y0 { stroke: yellow }" << endl
<< " #y1 { stroke: #0c0 }" << endl
<< " #y2 { stroke: #0aa }" << endl
<< " .y1thr { stroke: #f0f }" << endl
<< " rect.bar { fill: black }" << endl
<< " text.bar { fill: white }" << endl
<< " rect.space { fill: white }" << endl
<< " text.space { fill: black }" << endl
<< " text.data { fill: #44f; font-size: 16 }" << endl
<< "]]></style></defs>" << endl
<< "<image width='" << width * 2 << "' height='384'"
<< " preserveAspectRatio='none'"
<< " xlink:href='" << file << ".png'/>" << endl
<< "<g transform='translate(1,384) scale(2,-.5)'>" << endl;
// brute force
unsigned raw[width];
{
// extract scan from image pixels
image.modifyImage();
Magick::Pixels view(image);
Magick::PixelPacket *pxp = view.get(0, 0, width, 1);
Magick::ColorYUV y;
double max = 0;
svg << "<path id='raw' d='M";
unsigned i;
for(i = 0; i < inwidth; i++, pxp++) {
y = *pxp;
if(max < y.y())
max = y.y();
raw[i] = (unsigned)(y.y() * 0x100);
svg << ((i != 1) ? " " : " L ") << i << "," << raw[i];
y.u(0);
y.v(0);
*pxp = y;
}
y.y(max); /* flush scan FIXME? */
for(; i < inwidth + flush1; i++) {
raw[i] = (unsigned)(y.y() * 0x100);
svg << " " << i << "," << raw[i];
*pxp++ = y;
}
y.y(0);
for(; i < width; i++) {
raw[i] = (unsigned)(y.y() * 0x100);
svg << " " << i << "," << raw[i];
*pxp++ = y;
}
view.sync();
svg << "'/>" << endl
<< "</g>" << endl;
}
image.depth(8);
image.write(file + ".png");
// process scan and capture calculated values
unsigned cur_edge[width], last_edge[width];
int y0[width], y1[width], y2[width], y1_thr[width];
svg << "<g transform='translate(-3)'>" << endl;
for(unsigned i = 0; i < width; i++) {
int edge = scanner.scan_y(raw[i]);
unsigned x;
zbar_scanner_get_state(scanner.get_c_scanner(), &x,
&cur_edge[i], &last_edge[i],
&y0[i], &y1[i], &y2[i], &y1_thr[i]);
#ifdef DEBUG_SCANNER
cerr << endl;
#endif
cur_edge[i] += i - x;
if(edge) {
last_edge[i] += i - x;
unsigned w = scanner.get_width();
svg << "<rect x='" << (2. * (last_edge[i] - w) / ZBAR_FRAC)
<< "' width='" << (w * 2. / ZBAR_FRAC)
<< "' height='32' class='"
<< (scanner.get_color() ? "space" : "bar") << "'/>" << endl
<< "<text transform='translate("
<< ((2. * last_edge[i] - w) / ZBAR_FRAC) - 3
<< ",16) rotate(90)' class='"
<< (scanner.get_color() ? "space" : "bar") << "'>" << endl
<< w << "</text>" << endl;
zbar_symbol_type_t sym = decoder.decode_width(w);
if(sym > ZBAR_PARTIAL) {
svg << "<text transform='translate("
<< (2. * (last_edge[i] + w) / ZBAR_FRAC)
<< ",208) rotate(90)' class='data'>"
<< decoder.get_data_string() << "</text>" << endl;
}
}
else
last_edge[i] = 0;
}
svg << "</g>" << endl
<< "<g transform='translate(-3,384) scale(2,-.5)'>" << endl
<< "<path id='edges' d='";
for(unsigned i = 0; i < width; i++)
if(last_edge[i])
svg << " M" << ((double)last_edge[i] / ZBAR_FRAC) << ",0v768";
svg << "'/>" << endl
<< "</g>" << endl
<< "<g transform='translate(-1,384) scale(2,-.5)'>" << endl
<< "<path id='y0' d='M";
for(unsigned i = 0; i < width; i++)
svg << ((i != 1) ? " " : " L ") << i << "," << y0[i];
svg << "'/>" << endl
<< "</g>" << endl;
svg << "<g transform='translate(-1,128) scale(2,-1)'>" << endl
<< "<line id='zero' x2='" << width << "'/>" << endl
<< "<path id='cur-edge' d='";
for(unsigned i = 1; i < width - 1; i++)
if(!last_edge[i + 1] && (cur_edge[i] != cur_edge[i + 1]))
svg << " M" << ((double)cur_edge[i] / ZBAR_FRAC) - 1 << ",-32v64";
svg << "'/>" << endl
<< "<path class='y1thr' d='M";
for(unsigned i = 0; i < width; i++)
svg << ((i != 1) ? " " : " L ") << i << "," << y1_thr[i];
svg << "'/>" << endl
<< "<path class='y1thr' d='M";
for(unsigned i = 0; i < width; i++)
svg << ((i != 1) ? " " : " L ") << i << "," << -y1_thr[i];
svg << "'/>" << endl
<< "<path id='y1' d='M";
for(unsigned i = 0; i < width; i++)
svg << ((i != 1) ? " " : " L ") << (i - 0.5) << "," << y1[i];
svg << "'/>" << endl
<< "<path id='y2' d='M";
for(unsigned i = 0; i < width; i++)
svg << ((i != 1) ? " " : " L ") << i << "," << y2[i];
svg << "'/>" << endl
<< "</g>" << endl;
svg << "</svg>" << endl;
}
