From e2215bd04c4e19b82b6baf43fc63ea6f7351dd37 Mon Sep 17 00:00:00 2001 From: John Cupitt Date: Sat, 17 Aug 2013 16:59:28 +0100 Subject: [PATCH] redo im_histnD() as a class --- ChangeLog | 4 +- TODO | 3 + libvips/arithmetic/Makefile.am | 1 + libvips/arithmetic/arithmetic.c | 2 + libvips/arithmetic/hist_find.c | 3 + libvips/arithmetic/hist_find_ndim.c | 348 ++++++++++++++++++++++++++++ libvips/deprecated/vips7compat.c | 19 ++ libvips/histogram/Makefile.am | 1 - libvips/histogram/im_histnD.c | 270 --------------------- libvips/include/vips/arithmetic.h | 2 + libvips/include/vips/histogram.h | 1 - libvips/include/vips/vips7compat.h | 1 + 12 files changed, 381 insertions(+), 274 deletions(-) create mode 100644 libvips/arithmetic/hist_find_ndim.c delete mode 100644 libvips/histogram/im_histnD.c diff --git a/ChangeLog b/ChangeLog index abef4d30..309118c9 100644 --- a/ChangeLog +++ b/ChangeLog @@ -3,8 +3,8 @@ - rename image arrays as image matrices ... INTERPRETATION_ARRAY -> INTERPRETATION_MATRIX etc. - rewrite im_buildlut(), im_identity*(), im_maplut(), im_falsecolour(), - im_gammacorrect(), im_histgr(), im_histcum(), im_histnorm(), im_heq() - as classes + im_gammacorrect(), im_histgr(), im_histcum(), im_histnorm(), im_heq(), + im_histnD() as classes - added vips_error_freeze() / vips_error_thaw() - used freeze() / thaw() to stop file format sniffers logging spurious errors - vipsthumbnail uses embedded jpg thumbnails if it can diff --git a/TODO b/TODO index 84388473..55396302 100644 --- a/TODO +++ b/TODO @@ -1,3 +1,6 @@ +- im_histspec() is a binary hist operator ... need many inputs for + VipsHistogram and VipsHistBuffer + - use g_log() instead of vips_info() - what's the difference between buildlut and invertlut? can we make invertlut diff --git a/libvips/arithmetic/Makefile.am b/libvips/arithmetic/Makefile.am index 784a01b2..af3cbb0d 100644 --- a/libvips/arithmetic/Makefile.am +++ b/libvips/arithmetic/Makefile.am @@ -16,6 +16,7 @@ libarithmetic_la_SOURCES = \ min.c \ max.c \ hist_find.c \ + hist_find_ndim.c \ subtract.c \ math.c \ arithmetic.c \ diff --git a/libvips/arithmetic/arithmetic.c b/libvips/arithmetic/arithmetic.c index d92fec94..e70e25b6 100644 --- a/libvips/arithmetic/arithmetic.c +++ b/libvips/arithmetic/arithmetic.c @@ -691,6 +691,7 @@ vips_arithmetic_operation_init( void ) extern GType vips_sign_get_type( void ); extern GType vips_stats_get_type( void ); extern GType vips_hist_find_get_type( void ); + extern GType vips_hist_find_ndim_get_type( void ); extern GType vips_measure_get_type( void ); extern GType vips_round_get_type( void ); extern GType vips_relational_get_type( void ); @@ -721,6 +722,7 @@ vips_arithmetic_operation_init( void ) vips_sign_get_type(); vips_stats_get_type(); vips_hist_find_get_type(); + vips_hist_find_ndim_get_type(); vips_measure_get_type(); vips_round_get_type(); vips_relational_get_type(); diff --git a/libvips/arithmetic/hist_find.c b/libvips/arithmetic/hist_find.c index 75cd57c0..bf508629 100644 --- a/libvips/arithmetic/hist_find.c +++ b/libvips/arithmetic/hist_find.c @@ -420,6 +420,9 @@ vips_hist_find_init( VipsHistFind *hist_find ) * vips_hist_find: * @in: input image * @out: output image + * + * Optional arguments: + * * @band: band to equalise * * Find the histogram of @in. Find the histogram for band @band (producing a diff --git a/libvips/arithmetic/hist_find_ndim.c b/libvips/arithmetic/hist_find_ndim.c new file mode 100644 index 00000000..e6afd9b7 --- /dev/null +++ b/libvips/arithmetic/hist_find_ndim.c @@ -0,0 +1,348 @@ +/* n-dimensional histogram + * + * Written on: 8/7/03 + * 10/11/04 + * - oops, was not checking the bandfmt coming in + * 24/3/10 + * - gtkdoc + * - small celanups + * 17/8/13 + * - redo as a class + */ + +/* + + This file is part of VIPS. + + VIPS is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + 02110-1301 USA + + */ + +/* + + These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk + + */ + +#ifdef HAVE_CONFIG_H +#include +#endif /*HAVE_CONFIG_H*/ +#include + +#include +#include +#include + +#include + +#include "statistic.h" + +struct _VipsHistFindNDim; + +/* Accumulate a histogram in one of these. + */ +typedef struct { + struct _VipsHistFindNDim *ndim; + + int bins; + int max_val; + unsigned int ***data; +} Histogram; + +typedef struct _VipsHistFindNDim { + VipsStatistic parent_instance; + + /* Number of bins on each axis. + */ + int bins; + + /* Main image histogram. Subhists accumulate to this. + */ + Histogram *hist; + + /* Write hist to this output image. + */ + VipsImage *out; + +} VipsHistFindNDim; + +typedef VipsStatisticClass VipsHistFindNDimClass; + +G_DEFINE_TYPE( VipsHistFindNDim, vips_hist_find_ndim, VIPS_TYPE_STATISTIC ); + +/* Build a Histogram. + */ +static Histogram * +histogram_new( VipsHistFindNDim *ndim ) +{ + VipsImage *in = VIPS_STATISTIC( ndim )->ready; + VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( ndim ); + int bins = ndim->bins; + + /* How many dimensions do we need to allocate? + */ + int ilimit = in->Bands > 2 ? bins : 1; + int jlimit = in->Bands > 1 ? bins : 1; + + int i, j; + Histogram *hist; + + if( !(hist = VIPS_NEW( ndim, Histogram )) ) + return( NULL ); + + hist->ndim = ndim; + hist->bins = bins; + hist->max_val = in->BandFmt == VIPS_FORMAT_UCHAR ? 256 : 65536; + if( bins < 1 || + bins > hist->max_val ) { + vips_error( class->nickname, + _( "bins out of range [1,%d]" ), hist->max_val ); + return( NULL ); + } + + if( !(hist->data = VIPS_ARRAY( ndim, bins, unsigned int ** )) ) + return( NULL ); + memset( hist->data, 0, bins * sizeof( unsigned int ** ) ); + + for( i = 0; i < ilimit; i++ ) { + if( !(hist->data[i] = + VIPS_ARRAY( ndim, bins, unsigned int * )) ) + return( NULL ); + memset( hist->data[i], 0, bins * sizeof( unsigned int * ) ); + for( j = 0; j < jlimit; j++ ) { + if( !(hist->data[i][j] = + VIPS_ARRAY( ndim, bins, unsigned int )) ) + return( NULL ); + memset( hist->data[i][j], + 0, bins * sizeof( unsigned int ) ); + } + } + + return( hist ); +} + +static int +vips_hist_find_ndim_build( VipsObject *object ) +{ + VipsStatistic *statistic = VIPS_STATISTIC( object ); + VipsHistFindNDim *ndim = (VipsHistFindNDim *) object; + + unsigned int *obuffer; + int y, i, x, z; + + g_object_set( object, + "out", vips_image_new(), + NULL ); + + /* main hist made on first thread start. + */ + + if( VIPS_OBJECT_CLASS( vips_hist_find_ndim_parent_class )-> + build( object ) ) + return( -1 ); + + if( vips_image_copy_fields( ndim->out, statistic->ready ) ) + return( -1 ); + vips_image_init_fields( ndim->out, + ndim->bins, + statistic->ready->Bands > 1 ? ndim->bins : 1, + statistic->ready->Bands > 2 ? ndim->bins : 1, + VIPS_FORMAT_UINT, + VIPS_CODING_NONE, VIPS_INTERPRETATION_HISTOGRAM, 1.0, 1.0 ); + + if( !(obuffer = VIPS_ARRAY( ndim, + VIPS_IMAGE_N_ELEMENTS( ndim->out ), unsigned int )) ) + return( -1 ); + + for( y = 0; y < ndim->out->Ysize; y++ ) { + for( i = 0, x = 0; x < ndim->out->Xsize; x++ ) + for( z = 0; z < ndim->out->Bands; z++, i++ ) + obuffer[i] = ndim->hist->data[z][y][x]; + + if( vips_image_write_line( ndim->out, y, (VipsPel *) obuffer ) ) + return( -1 ); + } + + return( 0 ); +} + +static void * +vips_hist_find_ndim_start( VipsStatistic *statistic ) +{ + VipsHistFindNDim *ndim = (VipsHistFindNDim *) statistic; + + /* Make the main hist, if necessary. + */ + if( !ndim->hist ) + ndim->hist = histogram_new( ndim ); + + return( (void *) histogram_new( ndim ) ); +} + +/* Join a sub-hist onto the main hist. + */ +static int +vips_hist_find_ndim_stop( VipsStatistic *statistic, void *seq ) +{ + Histogram *sub_hist = (Histogram *) seq; + VipsHistFindNDim *ndim = (VipsHistFindNDim *) statistic; + Histogram *hist = ndim->hist; + + int i, j, k; + + for( i = 0; i < hist->bins; i++ ) + for( j = 0; j < hist->bins; j++ ) + for( k = 0; k < hist->bins; k++ ) + if( hist->data[i] && hist->data[i][j] ) { + hist->data[i][j][k] += + sub_hist->data[i][j][k]; + + /* Zap sub-hist to make sure we + * can't add it again. + */ + sub_hist->data[i][j][k] = 0; + } + + return( 0 ); +} + +#define LOOP( TYPE ) { \ + TYPE *p = (TYPE *) in; \ + \ + for( i = 0, j = 0; j < n; j++ ) { \ + for( k = 0; k < nb; k++, i++ ) \ + index[k] = p[i] / scale; \ + \ + hist->data[index[2]][index[1]][index[0]] += 1; \ + } \ +} + +static int +vips_hist_find_ndim_scan( VipsStatistic *statistic, void *seq, + int x, int y, void *in, int n ) +{ + Histogram *hist = (Histogram *) seq; + VipsImage *im = statistic->ready; + int nb = im->Bands; + double scale = (double) (hist->max_val + 1) / hist->bins; + int i, j, k; + int index[3]; + + /* Fill these with dimensions, backwards. + */ + index[0] = index[1] = index[2] = 0; + + switch( im->BandFmt ) { + case VIPS_FORMAT_UCHAR: + LOOP( unsigned char ); + break; + + case VIPS_FORMAT_USHORT: + LOOP( unsigned short ); + break; + + default: + g_assert( 0 ); + } + + return( 0 ); +} + +/* Save a bit of typing. + */ +#define UC VIPS_FORMAT_UCHAR +#define US VIPS_FORMAT_USHORT +#define UI VIPS_FORMAT_UINT + +/* Type mapping: go to uchar or ushort. + */ +static const VipsBandFormat vips_hist_find_ndim_format_table[10] = { +/* UC C US S UI I F X D DX */ + UC, UC, US, US, US, US, US, US, US, US +}; + +static void +vips_hist_find_ndim_class_init( VipsHistFindNDimClass *class ) +{ + GObjectClass *gobject_class = (GObjectClass *) class; + VipsObjectClass *object_class = (VipsObjectClass *) class; + VipsStatisticClass *sclass = VIPS_STATISTIC_CLASS( class ); + + gobject_class->set_property = vips_object_set_property; + gobject_class->get_property = vips_object_get_property; + + object_class->nickname = "hist_find_ndim"; + object_class->description = _( "find image histogram" ); + object_class->build = vips_hist_find_ndim_build; + + sclass->start = vips_hist_find_ndim_start; + sclass->scan = vips_hist_find_ndim_scan; + sclass->stop = vips_hist_find_ndim_stop; + sclass->format_table = vips_hist_find_ndim_format_table; + + VIPS_ARG_IMAGE( class, "out", 100, + _( "Output" ), + _( "Output histogram" ), + VIPS_ARGUMENT_REQUIRED_OUTPUT, + G_STRUCT_OFFSET( VipsHistFindNDim, out ) ); + + VIPS_ARG_INT( class, "bins", 110, + _( "Bins" ), + _( "Number of bins in each dimension" ), + VIPS_ARGUMENT_OPTIONAL_INPUT, + G_STRUCT_OFFSET( VipsHistFindNDim, bins ), + 1, 65536, 10 ); + +} + +static void +vips_hist_find_ndim_init( VipsHistFindNDim *ndim ) +{ + ndim->bins = 10; +} + +/** + * vips_hist_find_ndim: + * @in: input image + * @out: output image + * + * Optional arguments: + * + * @bins: number of bins to make on each axis + * + * Make a one, two or three dimensional histogram of a 1, 2 or + * 3 band image. Divide each axis into @bins bins .. ie. + * output is 1 x bins, bins x bins, or bins x bins x bins bands. + * @bins defaults to 10. + * + * Images are cast to uchar or ushort before histogramming. + * + * See also: vips_hist_find(), vips_hist_find_indexed(). + * + * Returns: 0 on success, -1 on error + */ +int +vips_hist_find_ndim( VipsImage *in, VipsImage **out, ... ) +{ + va_list ap; + int result; + + va_start( ap, out ); + result = vips_call_split( "hist_find_ndim", ap, in, out ); + va_end( ap ); + + return( result ); +} diff --git a/libvips/deprecated/vips7compat.c b/libvips/deprecated/vips7compat.c index a3387cce..cf476f00 100644 --- a/libvips/deprecated/vips7compat.c +++ b/libvips/deprecated/vips7compat.c @@ -3420,6 +3420,25 @@ im_histgr( IMAGE *in, IMAGE *out, int bandno ) return( 0 ); } +int +im_histnD( VipsImage *in, VipsImage *out, int bins ) +{ + VipsImage *x; + + if( vips_hist_find_ndim( in, &x, + "bins", bins, + NULL ) ) + return( -1 ); + + if( im_copy( x, out ) ) { + g_object_unref( x ); + return( -1 ); + } + g_object_unref( x ); + + return( 0 ); +} + int im_falsecolour( IMAGE *in, IMAGE *out ) { diff --git a/libvips/histogram/Makefile.am b/libvips/histogram/Makefile.am index e41ac1d8..75fa9484 100644 --- a/libvips/histogram/Makefile.am +++ b/libvips/histogram/Makefile.am @@ -11,7 +11,6 @@ libhistogram_la_SOURCES = \ hist_equal.c \ \ hist_dispatch.c \ - im_histnD.c \ im_histplot.c \ im_histindexed.c \ im_histspec.c \ diff --git a/libvips/histogram/im_histnD.c b/libvips/histogram/im_histnD.c deleted file mode 100644 index f0248688..00000000 --- a/libvips/histogram/im_histnD.c +++ /dev/null @@ -1,270 +0,0 @@ -/* n-dimensional histogram - * - * Written on: 8/7/03 - * 10/11/04 - * - oops, was not checking the bandfmt coming in - * 24/3/10 - * - gtkdoc - * - small celanups - */ - -/* - - This file is part of VIPS. - - VIPS is free software; you can redistribute it and/or modify - it under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - 02110-1301 USA - - */ - -/* - - These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk - - */ - -#ifdef HAVE_CONFIG_H -#include -#endif /*HAVE_CONFIG_H*/ -#include - -#include -#include -#include - -#include - -/* Accumulate a histogram in one of these. - */ -typedef struct { - IMAGE *in; - IMAGE *out; - int bins; - - unsigned int ***data; /* Gather stats here */ -} Histogram; - -/* Build a Histogram. - */ -static Histogram * -build_hist( IMAGE *in, IMAGE *out, int bins ) -{ - /* How many dimensions we we need to allocate? - */ - int ilimit = in->Bands > 2 ? bins : 1; - int jlimit = in->Bands > 1 ? bins : 1; - - int i, j; - Histogram *hist; - - if( !(hist = IM_NEW( out, Histogram )) ) - return( NULL ); - - hist->in = in; - hist->out = out; - hist->bins = bins; - - if( !(hist->data = IM_ARRAY( out, bins, unsigned int ** )) ) - return( NULL ); - memset( hist->data, 0, bins * sizeof( unsigned int ** ) ); - - for( i = 0; i < ilimit; i++ ) { - if( !(hist->data[i] = IM_ARRAY( out, bins, unsigned int * )) ) - return( NULL ); - memset( hist->data[i], 0, bins * sizeof( unsigned int * ) ); - for( j = 0; j < jlimit; j++ ) { - if( !(hist->data[i][j] = IM_ARRAY( out, - bins, unsigned int )) ) - return( NULL ); - memset( hist->data[i][j], - 0, bins * sizeof( unsigned int ) ); - } - } - - return( hist ); -} - -/* Build a sub-hist, based on the main hist. - */ -static void * -build_subhist( IMAGE *out, void *a, void *b ) -{ - Histogram *mhist = (Histogram *) a; - - return( (void *) - build_hist( mhist->in, mhist->out, mhist->bins ) ); -} - -/* Join a sub-hist onto the main hist. - */ -static int -merge_subhist( void *seq, void *a, void *b ) -{ - Histogram *shist = (Histogram *) seq; - Histogram *mhist = (Histogram *) a; - int i, j, k; - - /* Sanity! - */ - if( shist->in != mhist->in || shist->out != mhist->out ) - error_exit( "sanity failure in merge_subhist" ); - - /* Add on sub-data. - */ - for( i = 0; i < mhist->bins; i++ ) - for( j = 0; j < mhist->bins; j++ ) - for( k = 0; k < mhist->bins; k++ ) - if( mhist->data[i] && mhist->data[i][j] ) { - mhist->data[i][j][k] += - shist->data[i][j][k]; - - /* Zap sub-hist to make sure we - * can't add it again. - */ - shist->data[i][j][k] = 0; - } - - return( 0 ); -} - -#define LOOP( TYPE ) { \ - TYPE *p = (TYPE *) line;\ - \ - for( i = 0, x = 0; x < r->width; x++ ) { \ - for( z = 0; z < nb; z++, i++ ) \ - index[z] = p[i] / scale; \ - \ - hist->data[index[2]][index[1]][index[0]]++; \ - } \ -} - -static int -find_hist( REGION *reg, void *seq, void *a, void *b, gboolean *stop ) -{ - Histogram *hist = (Histogram *) seq; - Rect *r = ®->valid; - IMAGE *im = reg->im; - int le = r->left; - int to = r->top; - int bo = IM_RECT_BOTTOM(r); - int nb = im->Bands; - int max_val = im->BandFmt == IM_BANDFMT_UCHAR ? 256 : 65536; - int scale = max_val / hist->bins; - int x, y, z, i; - int index[3]; - - /* Fill these with dimensions, backwards. - */ - index[0] = index[1] = index[2] = 0; - - /* Accumulate! - */ - for( y = to; y < bo; y++ ) { - VipsPel *line = IM_REGION_ADDR( reg, le, y ); - - switch( im->BandFmt ) { - case IM_BANDFMT_UCHAR: - LOOP( unsigned char ); - break; - - case IM_BANDFMT_USHORT: - LOOP( unsigned char ); - break; - - default: - error_exit( "panic #34847563245" ); - } - } - - return( 0 ); -} - -/** - * im_histnD: - * @in: input image - * @out: output image - * @bins: number of bins to make on each axis - * - * Make a one, two or three dimensional histogram of a 1, 2 or - * 3 band image. Divide each axis into a certain number of bins .. ie. - * output is 1 x bins, bins x bins, or bins x bins x bins bands. - * uchar and ushort only. - * - * See also: im_histgr(), im_histindexed(). - * - * Returns: 0 on success, -1 on error - */ -int -im_histnD( IMAGE *in, IMAGE *out, int bins ) -{ - int max_val; - Histogram *mhist; - int x, y, z, i; - unsigned int *obuffer; - - /* Check images. PIO from in, WIO to out. - */ - if( im_check_uncoded( "im_histnD", in ) || - im_check_u8or16( "im_histnD", in ) || - im_pincheck( in ) || - im_outcheck( out ) ) - return( -1 ); - - max_val = in->BandFmt == IM_BANDFMT_UCHAR ? 256 : 65536; - if( bins < 1 || bins > max_val ) { - im_error( "im_histnD", - _( " bins out of range [1,%d]" ), max_val ); - return( -1 ); - } - - /* Build main hist we accumulate to. - */ - if( !(mhist = build_hist( in, out, bins )) ) - return( -1 ); - - /* Accumulate data. - */ - if( vips_sink( in, - build_subhist, find_hist, merge_subhist, mhist, NULL ) ) - return( -1 ); - - /* Make the output image. - */ - if( im_cp_desc( out, in ) ) - return( -1 ); - im_initdesc( out, - bins, in->Bands > 1 ? bins : 1, in->Bands > 2 ? bins : 1, - IM_BBITS_INT, IM_BANDFMT_UINT, - IM_CODING_NONE, IM_TYPE_HISTOGRAM, 1.0, 1.0, 0, 0 ); - if( im_setupout( out ) ) - return( -1 ); - - /* Interleave to output buffer. - */ - if( !(obuffer = IM_ARRAY( out, - IM_IMAGE_N_ELEMENTS( out ), unsigned int )) ) - return( -1 ); - - for( y = 0; y < out->Ysize; y++ ) { - for( i = 0, x = 0; x < out->Xsize; x++ ) - for( z = 0; z < out->Bands; z++, i++ ) - obuffer[i] = mhist->data[z][y][x]; - - if( im_writeline( y, out, (VipsPel *) obuffer ) ) - return( -1 ); - } - - return( 0 ); -} diff --git a/libvips/include/vips/arithmetic.h b/libvips/include/vips/arithmetic.h index 8809ea35..3ab18ed6 100644 --- a/libvips/include/vips/arithmetic.h +++ b/libvips/include/vips/arithmetic.h @@ -379,6 +379,8 @@ int vips_measure( VipsImage *in, VipsImage **out, int h, int v, ... ) __attribute__((sentinel)); int vips_hist_find( VipsImage *in, VipsImage **out, ... ) __attribute__((sentinel)); +int vips_hist_find_ndim( VipsImage *in, VipsImage **out, ... ) + __attribute__((sentinel)); #ifdef __cplusplus } diff --git a/libvips/include/vips/histogram.h b/libvips/include/vips/histogram.h index 1afe9601..1b7a569f 100644 --- a/libvips/include/vips/histogram.h +++ b/libvips/include/vips/histogram.h @@ -48,7 +48,6 @@ int vips_hist_equal( VipsImage *in, VipsImage **out, ... ) __attribute__((sentinel)); -int im_histnD( VipsImage *in, VipsImage *out, int bins ); int im_hist_indexed( VipsImage *index, VipsImage *value, VipsImage *out ); int im_invertlut( DOUBLEMASK *input, VipsImage *output, int lut_size ); diff --git a/libvips/include/vips/vips7compat.h b/libvips/include/vips/vips7compat.h index 1ef87008..d0af8f5c 100644 --- a/libvips/include/vips/vips7compat.h +++ b/libvips/include/vips/vips7compat.h @@ -856,6 +856,7 @@ int im_histcum( VipsImage *in, VipsImage *out ); int im_histnorm( VipsImage *in, VipsImage *out ); int im_histeq( VipsImage *in, VipsImage *out ); int im_heq( VipsImage *in, VipsImage *out, int bandno ); +int im_histnD( VipsImage *in, VipsImage *out, int bins ); /* ruby-vips uses this */