static int
ifthenelse( IMAGE *c, IMAGE *a, IMAGE *b, IMAGE *out )
{
IMAGE **in;
/* Check args.
*/
if( im_check_uncoded( "im_ifthenelse", c ) ||
im_check_coding_known( "im_ifthenelse", a ) ||
im_check_coding_known( "im_ifthenelse", b ) ||
im_check_format( "ifthenelse", c, IM_BANDFMT_UCHAR ) ||
im_check_format_same( "ifthenelse", a, b ) ||
im_check_bands_same( "ifthenelse", a, b ) ||
im_check_bands_1orn( "im_ifthenelse", c, a ) ||
im_piocheck( c, out ) ||
im_pincheck( a ) ||
im_pincheck( b ) )
return( -1 );
/* Make output image.
*/
if( im_demand_hint( out, IM_THINSTRIP, c, a, b, NULL ) ||
im_cp_descv( out, a, b, c, NULL ) ||
!(in = im_allocate_input_array( out, c, a, b, NULL )) ||
im_generate( out,
im_start_many, ifthenelse_gen, im_stop_many,
in, NULL ) )
return( -1 );
return( 0 );
}
/**
* im_maplut:
* @in: input image
* @out: output image
* @lut: look-up table
*
* Map an image through another image acting as a LUT (Look Up Table).
* The lut may have any type, and the output image will be that type.
*
* The input image will be cast to one of the unsigned integer types, that is,
* IM_BANDFMT_UCHAR, IM_BANDFMT_USHORT or IM_BANDFMT_UINT.
*
* If @lut is too small for the input type (for example, if @in is
* IM_BANDFMT_UCHAR but @lut only has 100 elements), the lut is padded out
* by copying the last element. Overflows are reported at the end of
* computation.
* If @lut is too large, extra values are ignored.
*
* If @lut has one band, then all bands of @in pass through it. If @lut
* has same number of bands as @in, then each band is mapped
* separately. If @in has one band, then @lut may have many bands and
* the output will have the same number of bands as @lut.
*
* See also: im_histgr(), im_identity().
*
* Returns: 0 on success, -1 on error
*/
int
im_maplut( IMAGE *in, IMAGE *out, IMAGE *lut )
{
IMAGE *t;
LutInfo *st;
/* Check input output. Old-style IO from lut, for simplicity.
*/
if( im_check_hist( "im_maplut", lut ) ||
im_check_uncoded( "im_maplut", lut ) ||
im_check_uncoded( "im_maplut", in ) ||
im_check_bands_1orn( "im_maplut", in, lut ) ||
im_piocheck( in, out ) ||
im_incheck( lut ) )
return( -1 );
/* Cast in to u8/u16/u32.
*/
if( !(t = im_open_local( out, "im_maplut", "p" )) ||
im_clip2fmt( in, t, bandfmt_maplut[in->BandFmt] ) )
return( -1 );
/* Prepare the output header.
*/
if( im_cp_descv( out, t, lut, NULL ) )
return( -1 );
/* Force output to be the same type as lut.
*/
out->BandFmt = lut->BandFmt;
/* Output has same number of bands as LUT, unless LUT has 1 band, in
* which case output has same number of bands as input.
*/
if( lut->Bands != 1 )
out->Bands = lut->Bands;
/* Make tables.
*/
if( !(st = build_luts( out, lut )) )
return( -1 );
/* Set demand hints.
*/
if( im_demand_hint( out, IM_THINSTRIP, t, NULL ) )
return( -1 );
/* Process!
*/
if( im_generate( out, maplut_start, maplut_gen, maplut_stop, t, st ) )
return( -1 );
return( 0 );
}
