LQR_CARVER_LIST_FOREACH(3) LqR library API reference LQR_CARVER_LIST_FOREACH(3)NAME
lqr_carver_list_foreach - perform operations on all LqrCarver objects in an LqrCarverList object
SYNOPSIS
#include <lqr.h>
LqrRetVal lqr_carver_list_foreach(LqrCarverList* list, LqrCarverFunc func, LqrDataTok data);
LqrRetVal lqr_carver_list_foreach_recursive(LqrCarverList* list, LqrCarverFunc func, LqrDataTok data);
DESCRIPTION
The function lqr_carver_list_foreach can be used to apply the function func to all the LqrCarver objects listed in list. The parameter data
is used to pass arguments to the function.
The list value should be obtained through the function lqr_carver_list_start(3). The order in the list will then follow the one in which
carver objects were attached.
The function func is of type LqrCarverFunc, whose prototype is defined by:
typedef LqrRetVal (*LqrCarverFunc) (LqrCarver *carver, LqrDataTok data);
The data argument is of type LqrDataTok, which is defined as a union with the following fields:
o LqrCarver* carver
o gint integer
o gpointer data
The function lqr_carver_list_foreach_recursive is equivelant to lqr_carver_list_foreach, but it works recursively if the LqrCarver objects
in list have themselves other attached LqrCarver objects attached. In this case, the function func will be applied to each element of the
list and to each element of the attached list recursively, before moving on to the next element.
SEE ALSO LqrRetVal(3), lqr_carver_attach(3), lqr_carver_list_start(3), lqr_carver_list_current(3), lqr_carver_list_next(3)COPYRIGHT
Copyright (C) 2007-2009 Carlo Baldassi
LqR library 0.4.1 API (3:1:3) 10 Maj 2009 LQR_CARVER_LIST_FOREACH(3)
Check Out this Related Man Page
LQR_CARVER_BIAS_ADD(3) LqR library API reference LQR_CARVER_BIAS_ADD(3)NAME
lqr_carver_bias_add_xy, lqr_carver_bias_add_area, lqr_carver_bias_add, lqr_carver_bias_add_rgb_area, lqr_carver_bias_add_rgb - update an
LqrCarver bias
SYNOPSIS
#include <lqr.h>
LqrRetVal lqr_carver_bias_add_xy(LqrCarver* carver, gdouble bias, gint x, gint y);
LqrRetVal lqr_carver_bias_add_area(LqrCarver* carver, gdouble* buffer, gint bias_factor, gint width, gint height, gint x_off, gint y_off);
LqrRetVal lqr_carver_bias_add(LqrCarver* carver, gdouble* buffer, gint bias_factor);
LqrRetVal lqr_carver_bias_add_rgb_area(LqrCarver* carver, gdouble* buffer, gint bias_factor, gint channels, gint width, gint height,
gint x_off, gint y_off);
LqrRetVal lqr_carver_bias_add_rgb(LqrCarver* carver, gdouble* buffer, gint bias_factor, gint channels);
FOREWORD
All the functions described in this page are used to add a bias to LqrCarver objects. A positive biased pixel will be more likely to be
avoided by seams, and thus be preserved during rescaling, while a negative bias has the opposite effect.
All of these functions must be called before lqr_carver_resize(3). If called multiple times, the biases added at each call will sum up.
ADDING A BIAS PIXEL BY PIXEL
The function lqr_carver_bias_add_xy adds a bias to the x, y pixel of the image loaded into the LqrCarver object pointed to by carver
A typical value for bias_factor would be 1000 (in absolute value).
ADDING A BIAS FROM A BUFFER
The function lqr_carver_bias_add_area adds a bias to an area of the image loaded into the LqrCarver object pointed to by carver.
The parameter buffer must point to an array of doubles of size width * height, ordered first by rows, then by columns.
The offset of the area relative to the image can be specified through x_off and y_off. The bias area can exceed the boundary of the image,
and the offsets can be negative.
The parameter bias_factor is an overall bias scale. A typical value when the buffer contents are of the order of 1 would be 1000 (in
absolute value).
The function lqr_carver_bias_add can be used when the area to add is of the same size of the image loaded in the LqrCarver object and the
offsets are 0.
ADDING A BIAS FROM AN IMAGE
The functions lqr_carver_bias_add_rgb_area and lqr_carver_bias_add_rgb are very similar to lqr_carver_bias_add_area and
lqr_carver_bias_add, except that they use 8-bit multi-channel images as inputs.
The number of channels in the image is passed via the parameter channels. The last channel is assumed to be the alpha (opacity) channel if
channels is equal to 2 or greater than 3 (if this is not the case, use the previous functions).
The bias is computed from the average of the colour channels, multiplied by the value of the alpha channel if present. For example, in RGBA
images a white, nontransparent pixel is equivalent to a value of 1.0 when using a buffer in lqr_carver_bias_add_area.
RETURN VALUES
The return values follow the Liquid Rescale library signalling system.
SEE ALSO LqrRetVal(3), lqr_carver_init(3), lqr_carver_rigmask_add(3)COPYRIGHT
Copyright (C) 2007-2009 Carlo Baldassi
LqR library 0.4.1 API (3:1:3) 10 Maj 2009 LQR_CARVER_BIAS_ADD(3)