const Graphics::Surface *MSRLEDecoder::decodeFrame(Common::SeekableReadStream &stream) {
if (_bitsPerPixel == 8) {
decode8(stream);
} else
error("Unhandled %d bit Microsoft RLE encoding", _bitsPerPixel);
return _surface;
}
int sysUncrypt(char* src,int indexsrc,int len,int lensrc,unsigned int key,int alpha)
{
if ((indexsrc<0)||(indexsrc+len>lensrc)||(len<=0)) return -1;
return decode8(src+indexsrc,len,key,alpha);
}
int sampleLine(const String &line, int y, String &code)
{
double mean = 0;
int i=0, x=0, w=line.size();
// find quiet zones:
Point sl = detail::quietZone(line, 0, w/2, 1, mean );
Point sr = detail::quietZone(line, w-1, w/2, -1, mean );
int distance = sr.x - sl.x;
if ( distance < 58 )
{
return 1; // too short
}
// try to sample a square wave from the grayscale data
// between the quiet zones,
// start at first black pixel
bool last_state = true;
vector<Point> pt(1,Point(0,0)); // pos,length, pos,length, ..
for ( i = sl.x+1; i<sr.x; i++ )
{
// todo : proper nms
bool state = (line[i] < mean);
// toggle state:
if ( state != last_state )
{
pt.push_back(Point(i, 1));
last_state = state;
continue;
}
// state unchanged, increase length of current section
pt.back().y ++;
}
// ean13 has 95 bits and 58 state toggles,
// ean8 has 67 bits and 42 state toggles.
double siz = distance;
if ( pt.size() == 58 )
{
siz /= 95.0; // ean13
}
else
if ( pt.size() == 42 )
{
siz /= 67.0; // ean8
}
else
{
return 2; // no match to either ean8 or ean13
}
// scale pattern down to 1 pixel per bit:
int sum = 0;
double last = (sl.x+1);
for( i=0; i<pt.size(); i++ )
{
double d = pt[i].x - last;
last = pt[i].x;
d = int( 0.5 + d/siz ); // floor ?
sum += d;
pt[i].y = d; // now holds bit count
}
if ( sum > 95 )
{
return 3; // too long
}
// make bitstring:
bool bit = true;
String bits = "";
for( int i=0; i<pt.size(); i++ )
{
for( int j=0; j<pt[i].y; j++ )
{
bits += ( bit ? '1' : '0' );
if ( bits.size() > 95 )
{
return 4; // still too long
}
}
bit = ! bit;
}
bits += '1';
if ( bits.size() == 67 )
return decode8( bits, code );
if ( bits.size() == 95 )
return decode13( bits, code );
return 4; // no match to either ean8 or ean13
}