NAME
Image::Leptonica::Func::seedfilllow
VERSION
version 0.04
seedfilllow.c
seedfilllow.c
Seedfill:
Gray seedfill (source: Luc Vincent:fast-hybrid-grayscale-reconstruction)
void seedfillBinaryLow()
void seedfillGrayLow()
void seedfillGrayInvLow()
void seedfillGrayLowSimple()
void seedfillGrayInvLowSimple()
Distance function:
void distanceFunctionLow()
Seed spread:
void seedspreadLow()FUNCTIONS
distanceFunctionLow
void distanceFunctionLow ( l_uint32 *datad, l_int32 w, l_int32 h, l_int32 d, l_int32 wpld, l_int32 connectivity )
distanceFunctionLow()seedfillBinaryLow
void seedfillBinaryLow ( l_uint32 *datas, l_int32 hs, l_int32 wpls, l_uint32 *datam, l_int32 hm, l_int32 wplm, l_int32 connectivity )
seedfillBinaryLow()
Notes:
(1) This is an in-place fill, where the seed image is
filled, clipping to the filling mask, in one full
cycle of UL -> LR and LR -> UL raster scans.
(2) Assume the mask is a filling mask, not a blocking mask.
(3) Assume that the RHS pad bits of the mask
are properly set to 0.
(4) Clip to the smallest dimensions to avoid invalid reads.seedfillGrayInvLow
void seedfillGrayInvLow ( l_uint32 *datas, l_int32 w, l_int32 h, l_int32 wpls, l_uint32 *datam, l_int32 wplm, l_int32 connectivity )
seedfillGrayInvLow()
Notes:
(1) The pixels are numbered as follows:
1 2 3
4 x 5
6 7 8
This low-level filling operation consists of two scans,
raster and anti-raster, covering the entire seed image.
During the anti-raster scan, every pixel p such that its
current value could still be propogated during the next
raster scanning is put into the FIFO-queue.
Next step is the propagation step where where we update
and propagate the values using FIFO structure created in
anti-raster scan.
(2) The "Inv" signifies the fact that in this case, filling
of the seed only takes place when the seed value is
greater than the mask value. The mask will act to stop
the fill when it is higher than the seed level. (This is
in contrast to conventional grayscale filling where the
seed always fills below the mask.)
(3) An example of use is a basin, described by the mask (pixm),
where within the basin, the seed pix (pixs) gets filled to the
height of the highest seed pixel that is above its
corresponding max pixel. Filling occurs while the
propagating seed pixels in pixs are larger than the
corresponding mask values in pixm.
(4) Reference paper :
L. Vincent, Morphological grayscale reconstruction in image
analysis: applications and efficient algorithms, IEEE Transactions
on Image Processing, vol. 2, no. 2, pp. 176-201, 1993.seedfillGrayInvLowSimple
void seedfillGrayInvLowSimple ( l_uint32 *datas, l_int32 w, l_int32 h, l_int32 wpls, l_uint32 *datam, l_int32 wplm, l_int32 connectivity )
seedfillGrayInvLowSimple()
Notes:
(1) The pixels are numbered as follows:
1 2 3
4 x 5
6 7 8
This low-level filling operation consists of two scans,
raster and anti-raster, covering the entire seed image.
The caller typically iterates until the filling is
complete.
(2) The "Inv" signifies the fact that in this case, filling
of the seed only takes place when the seed value is
greater than the mask value. The mask will act to stop
the fill when it is higher than the seed level. (This is
in contrast to conventional grayscale filling where the
seed always fills below the mask.)
(3) An example of use is a basin, described by the mask (pixm),
where within the basin, the seed pix (pixs) gets filled to the
height of the highest seed pixel that is above its
corresponding max pixel. Filling occurs while the
propagating seed pixels in pixs are larger than the
corresponding mask values in pixm.seedfillGrayLow
void seedfillGrayLow ( l_uint32 *datas, l_int32 w, l_int32 h, l_int32 wpls, l_uint32 *datam, l_int32 wplm, l_int32 connectivity )
seedfillGrayLow()
Notes:
(1) The pixels are numbered as follows:
1 2 3
4 x 5
6 7 8
This low-level filling operation consists of two scans,
raster and anti-raster, covering the entire seed image.
This is followed by a breadth-first propagation operation to
complete the fill.
During the anti-raster scan, every pixel p whose current value
could still be propagated after the anti-raster scan is put into
the FIFO queue.
The propagation step is a breadth-first fill to completion.
Unlike the simple grayscale seedfill pixSeedfillGraySimple(),
where at least two full raster/anti-raster iterations are required
for completion and verification, the hybrid method uses only a
single raster/anti-raster set of scans.
(2) The filling action can be visualized from the following example.
Suppose the mask, which clips the fill, is a sombrero-shaped
surface, where the highest point is 200 and the low pixels
around the rim are 30. Beyond the rim, the mask goes up a bit.
Suppose the seed, which is filled, consists of a single point
of height 150, located below the max of the mask, with
the rest 0. Then in the raster scan, nothing happens until
the high seed point is encountered, and then this value is
propagated right and down, until it hits the side of the
sombrero. The seed can never exceed the mask, so it fills
to the rim, going lower along the mask surface. When it
passes the rim, the seed continues to fill at the rim
height to the edge of the seed image. Then on the
anti-raster scan, the seed fills flat inside the
sombrero to the upper and left, and then out from the
rim as before. The final result has a seed that is
flat outside the rim, and inside it fills the sombrero
but only up to 150. If the rim height varies, the
filled seed outside the rim will be at the highest
point on the rim, which is a saddle point on the rim.
(3) Reference paper :
L. Vincent, Morphological grayscale reconstruction in image
analysis: applications and efficient algorithms, IEEE Transactions
on Image Processing, vol. 2, no. 2, pp. 176-201, 1993.seedfillGrayLowSimple
void seedfillGrayLowSimple ( l_uint32 *datas, l_int32 w, l_int32 h, l_int32 wpls, l_uint32 *datam, l_int32 wplm, l_int32 connectivity )
seedfillGrayLowSimple()
Notes:
(1) The pixels are numbered as follows:
1 2 3
4 x 5
6 7 8
This low-level filling operation consists of two scans,
raster and anti-raster, covering the entire seed image.
The caller typically iterates until the filling is
complete.
(2) The filling action can be visualized from the following example.
Suppose the mask, which clips the fill, is a sombrero-shaped
surface, where the highest point is 200 and the low pixels
around the rim are 30. Beyond the rim, the mask goes up a bit.
Suppose the seed, which is filled, consists of a single point
of height 150, located below the max of the mask, with
the rest 0. Then in the raster scan, nothing happens until
the high seed point is encountered, and then this value is
propagated right and down, until it hits the side of the
sombrero. The seed can never exceed the mask, so it fills
to the rim, going lower along the mask surface. When it
passes the rim, the seed continues to fill at the rim
height to the edge of the seed image. Then on the
anti-raster scan, the seed fills flat inside the
sombrero to the upper and left, and then out from the
rim as before. The final result has a seed that is
flat outside the rim, and inside it fills the sombrero
but only up to 150. If the rim height varies, the
filled seed outside the rim will be at the highest
point on the rim, which is a saddle point on the rim.seedspreadLow
void seedspreadLow ( l_uint32 *datad, l_int32 w, l_int32 h, l_int32 wpld, l_uint32 *datat, l_int32 wplt, l_int32 connectivity )
seedspreadLow()
See pixSeedspread() for a brief description of the algorithm here.AUTHOR
Zakariyya Mughal <zmughal@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2014 by Zakariyya Mughal.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.