Method
VipsImageglobalbalance
Declaration [src]
int
vips_globalbalance (
VipsImage* in,
VipsImage** out,
...
)
Description [src]
Optional arguments:
gamma: gamma of source imagesint_output:TRUEfor integer image output
vips_globalbalance() can be used to remove contrast differences in
an assembled mosaic.
It reads the History field attached to in and builds a list of the source
images that were used to make the mosaic and the position that each ended
up at in the final image.
It opens each of the source images in turn and extracts all parts which
overlap with any of the other images. It finds the average values in the
overlap areas and uses least-mean-square to find a set of correction
factors which will minimise overlap differences. It uses gamma to
gamma-correct the source images before calculating the factors. A value of
1.0 will stop this.
Each of the source images is transformed with the appropriate correction
factor, then the mosaic is reassembled. out is #VIPS_FORMAT_FLOAT, but
if int_output is set, the output image is the same format as the input images.
There are some conditions that must be met before this operation can work:
the source images must all be present under the filenames recorded in the
history on in, and the mosaic must have been built using only operations in
this package.
See also: vips_remosaic().
This method is not directly available to language bindings.
Parameters
out-
Type:
VipsImageOutput image.
The argument will be set by the function. The caller of the method takes ownership of the returned data, and is responsible for freeing it. ...-
Type:
NULL-terminated list of optional named arguments.