void
cjb2(const GURL &urlin, const GURL &urlout, cjb2opts &opts)
{
GP<ByteStream> ibs=ByteStream::create(urlin, "rb");
CCImage rimg;
#if HAVE_TIFF
if (is_tiff(ibs))
read_tiff(rimg, ibs, opts);
else
#endif
{
GP<GBitmap> input=GBitmap::create(*ibs);
rimg.init(input->columns(), input->rows(), opts.dpi);
rimg.add_bitmap_runs(*input);
}
if (opts.verbose)
DjVuFormatErrorUTF8( "%s\t%d", ERR_MSG("cjb2.runs"),
rimg.runs.size() );
// Component analysis
rimg.make_ccids_by_analysis(); // obtain ccids
rimg.make_ccs_from_ccids(); // compute cc descriptors
if (opts.verbose)
DjVuFormatErrorUTF8( "%s\t%d", ERR_MSG("cjb2.ccs_before"),
rimg.ccs.size());
if (opts.losslevel > 0)
rimg.erase_tiny_ccs(); // clean
rimg.merge_and_split_ccs(); // reorganize weird ccs
rimg.sort_in_reading_order(); // sort cc descriptors
if (opts.verbose)
DjVuFormatErrorUTF8( "%s\t%d", ERR_MSG("cjb2.ccs_after"),
rimg.ccs.size());
// Pattern matching
GP<JB2Image> jimg = rimg.get_jb2image(); // get ``raw'' jb2image
rimg.runs.empty(); // save memory
rimg.ccs.empty(); // save memory
if (opts.losslevel>1)
tune_jb2image_lossy(jimg, opts.dpi, opts.losslevel);
else
tune_jb2image_lossless(jimg);
if (opts.verbose)
{
int nshape=0, nrefine=0;
for (int i=0; i<jimg->get_shape_count(); i++) {
if (!jimg->get_shape(i).bits) continue;
if (jimg->get_shape(i).parent >= 0) nrefine++;
nshape++;
}
DjVuFormatErrorUTF8( "%s\t%d\t%d", ERR_MSG("cjb2.shapes"),
nshape, nrefine);
}
// Code
GP<ByteStream> obs=ByteStream::create(urlout, "wb");
GP<IFFByteStream> giff=IFFByteStream::create(obs);
IFFByteStream &iff=*giff;
// -- main composite chunk
iff.put_chunk("FORM:DJVU", 1);
// -- ``INFO'' chunk
GP<DjVuInfo> ginfo=DjVuInfo::create();
DjVuInfo &info=*ginfo;
info.height = rimg.height;
info.width = rimg.width;
info.dpi = opts.dpi;
iff.put_chunk("INFO");
info.encode(*iff.get_bytestream());
iff.close_chunk();
// -- ``Sjbz'' chunk
iff.put_chunk("Sjbz");
jimg->encode(iff.get_bytestream());
iff.close_chunk();
// -- terminate main composite chunk
iff.close_chunk();
// Finished!
}
static void
read_tiff(CCImage &rimg, ByteStream *bs, cjb2opts &opts)
{
TIFF *tiff = TIFFClientOpen("libtiff", "rm", (thandle_t)bs,
readproc, writeproc, seekproc,
closeproc, sizeproc,
mapproc, unmapproc );
// bitonal
uint16 bps = 0, spp = 0;
TIFFGetFieldDefaulted(tiff, TIFFTAG_BITSPERSAMPLE, &bps);
TIFFGetFieldDefaulted(tiff, TIFFTAG_SAMPLESPERPIXEL, &spp);
if (bps != 1 || spp != 1)
G_THROW("Tiff image is not bitonal");
// photometric
uint16 photo = PHOTOMETRIC_MINISWHITE;
TIFFGetFieldDefaulted(tiff, TIFFTAG_PHOTOMETRIC, &photo);
// image size
uint32 w, h;
if (!TIFFGetFieldDefaulted(tiff, TIFFTAG_IMAGEWIDTH, &w) ||
!TIFFGetFieldDefaulted(tiff, TIFFTAG_IMAGELENGTH, &h) )
G_THROW("Tiff image size is not defined");
// resolution
float xres, yres;
if (TIFFGetFieldDefaulted(tiff, TIFFTAG_XRESOLUTION, &xres) &&
TIFFGetFieldDefaulted(tiff, TIFFTAG_YRESOLUTION, &yres) )
{
if (xres != yres)
DjVuPrintErrorUTF8( "cjb2: X- and Y-resolution do not match\n");
if (! opts.forcedpi)
opts.dpi = (int) (xres + yres) / 2;
}
// init rimg
rimg.init(w, h, opts.dpi);
// allocate scanline
tsize_t scanlinesize = TIFFScanlineSize(tiff);
scanlinesize = MAX(scanlinesize,1);
unsigned char *scanline = 0;
GPBuffer<unsigned char> gscanline(scanline, scanlinesize);
// iterate on rows
for (int y=0; y<(int)h; y++)
{
int yy = h - y - 1;
if (TIFFReadScanline(tiff, (tdata_t)scanline, y) < 0)
G_THROW("Tiff file is corrupted (TIFFReadScanline)");
if (photo != PHOTOMETRIC_MINISWHITE)
for (int i=0; i<(int)scanlinesize; i++)
scanline[i] ^= 0xff;
int lastx=0, off=0;
unsigned char mask=0, c=0, b=0;
for (int x=0; x<(int)w; x++)
{
if (! mask)
{
b = scanline[off++];
while (b==c && x+8<(int)w )
{
x = x + 8; // speedup
b = scanline[off++];
}
mask = 0x80;
}
if ( (b ^ c) & mask )
{
c ^= 0xff;
if (c)
lastx = x;
else
rimg.add_single_run(yy, lastx, x-1);
}
mask >>= 1;
}
if (c)
rimg.add_single_run(yy, lastx, w-1);
}
// close
TIFFClose(tiff);
}
