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libvips/libvips/foreign/pdfload.c

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/* load PDF with libpoppler
*
* 7/2/16
* - from openslideload.c
* 12/5/16
* - add @n ... number of pages to load
* 23/11/16
* - set page-height, if we can
* 28/6/17
* - use a much larger strip size, thanks bubba
* 8/6/18
* - add background param
* 16/8/18 [kleisauke]
* - shut down the input file as soon as we can
* 19/9/19
* - reopen the input if we minimised too early
* 11/3/20
* - move on top of VipsSource
*/
/*
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
*/
/*
#define DEBUG
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <vips/vips.h>
#include <vips/buf.h>
#include <vips/internal.h>
#include "pforeign.h"
/* TODO ... put minimise support back in.
*/
#if defined(HAVE_POPPLER)
#include <cairo.h>
#include <poppler.h>
#define VIPS_TYPE_FOREIGN_LOAD_PDF (vips_foreign_load_pdf_get_type())
#define VIPS_FOREIGN_LOAD_PDF( obj ) \
(G_TYPE_CHECK_INSTANCE_CAST( (obj), \
VIPS_TYPE_FOREIGN_LOAD_PDF, VipsForeignLoadPdf ))
#define VIPS_FOREIGN_LOAD_PDF_CLASS( klass ) \
(G_TYPE_CHECK_CLASS_CAST( (klass), \
VIPS_TYPE_FOREIGN_LOAD_PDF, VipsForeignLoadPdfClass))
#define VIPS_IS_FOREIGN_LOAD_PDF( obj ) \
(G_TYPE_CHECK_INSTANCE_TYPE( (obj), VIPS_TYPE_FOREIGN_LOAD_PDF ))
#define VIPS_IS_FOREIGN_LOAD_PDF_CLASS( klass ) \
(G_TYPE_CHECK_CLASS_TYPE( (klass), VIPS_TYPE_FOREIGN_LOAD_PDF ))
#define VIPS_FOREIGN_LOAD_PDF_GET_CLASS( obj ) \
(G_TYPE_INSTANCE_GET_CLASS( (obj), \
VIPS_TYPE_FOREIGN_LOAD_PDF, VipsForeignLoadPdfClass ))
typedef struct _VipsForeignLoadPdf {
VipsForeignLoad parent_object;
/* The VipsSource we load from, and the GInputStream we wrap around
* it. Set from subclasses.
*/
VipsSource *source;
GInputStream *stream;
/* Load this page.
*/
int page_no;
/* Load this many pages.
*/
int n;
/* Render at this DPI.
*/
double dpi;
/* Calculate this from DPI. At 72 DPI, we render 1:1 with cairo.
*/
double scale;
/* Background colour.
*/
VipsArrayDouble *background;
/* Poppler is not thread-safe, so we run inside a single-threaded
* cache. On the plus side, this means we only need one @page pointer,
* even though we change this during _generate().
*/
PopplerDocument *doc;
PopplerPage *page;
int current_page;
/* Doc has this many pages.
*/
int n_pages;
/* We need to read out the size of each page we will render, and lay
* them out in the final image.
*/
VipsRect image;
VipsRect *pages;
/* The [double] background converted to the image format.
*/
VipsPel *ink;
} VipsForeignLoadPdf;
typedef struct _VipsForeignLoadPdfClass {
VipsForeignLoadClass parent_class;
} VipsForeignLoadPdfClass;
G_DEFINE_ABSTRACT_TYPE( VipsForeignLoadPdf, vips_foreign_load_pdf,
VIPS_TYPE_FOREIGN_LOAD );
static void
vips_foreign_load_pdf_dispose( GObject *gobject )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( gobject );
VIPS_UNREF( pdf->page );
VIPS_UNREF( pdf->doc );
VIPS_UNREF( pdf->source );
VIPS_UNREF( pdf->stream );
G_OBJECT_CLASS( vips_foreign_load_pdf_parent_class )->
dispose( gobject );
}
static int
vips_foreign_load_pdf_build( VipsObject *object )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( object );
GError *error = NULL;
if( !vips_object_argument_isset( object, "scale" ) )
pdf->scale = pdf->dpi / 72.0;
pdf->stream = vips_g_input_stream_new_from_source( pdf->source );
if( !(pdf->doc = poppler_document_new_from_stream( pdf->stream,
vips_source_length( pdf->source ), NULL, NULL, &error )) ) {
vips_g_error( &error );
return( -1 );
}
if( VIPS_OBJECT_CLASS( vips_foreign_load_pdf_parent_class )->
build( object ) )
return( -1 );
return( 0 );
}
static VipsForeignFlags
vips_foreign_load_pdf_get_flags_filename( const char *filename )
{
/* We can render any part of the page on demand.
*/
return( VIPS_FOREIGN_PARTIAL );
}
static VipsForeignFlags
vips_foreign_load_pdf_get_flags( VipsForeignLoad *load )
{
return( VIPS_FOREIGN_PARTIAL );
}
static int
vips_foreign_load_pdf_get_page( VipsForeignLoadPdf *pdf, int page_no )
{
if( pdf->current_page != page_no ||
!pdf->page ) {
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( pdf );
VIPS_UNREF( pdf->page );
pdf->current_page = -1;
#ifdef DEBUG
printf( "vips_foreign_load_pdf_get_page: %d\n", page_no );
#endif /*DEBUG*/
if( !(pdf->page = poppler_document_get_page( pdf->doc,
page_no )) ) {
vips_error( class->nickname,
_( "unable to load page %d" ), page_no );
return( -1 );
}
pdf->current_page = page_no;
}
return( 0 );
}
/* String-based metadata fields we extract.
*/
typedef struct _VipsForeignLoadPdfMetadata {
char *(*pdf_fetch)( PopplerDocument *doc );
char *field;
} VipsForeignLoadPdfMetadata;
static VipsForeignLoadPdfMetadata vips_foreign_load_pdf_metadata[] = {
{ poppler_document_get_title, "pdf-title" },
{ poppler_document_get_author, "pdf-author" },
{ poppler_document_get_subject, "pdf-subject" },
{ poppler_document_get_keywords, "pdf-keywords" },
{ poppler_document_get_creator, "pdf-creator" },
{ poppler_document_get_producer, "pdf-producer" },
{ poppler_document_get_metadata, "pdf-metadata" },
};
static int n_metadata = VIPS_NUMBER( vips_foreign_load_pdf_metadata );
static int
vips_foreign_load_pdf_set_image( VipsForeignLoadPdf *pdf, VipsImage *out )
{
int i;
double res;
#ifdef DEBUG
printf( "vips_foreign_load_pdf_set_image: %p\n", pdf );
#endif /*DEBUG*/
/* We render to a linecache, so fat strips work well.
*/
vips_image_pipelinev( out, VIPS_DEMAND_STYLE_FATSTRIP, NULL );
/* Extract and attach metadata. Set the old name too for compat.
*/
vips_image_set_int( out, "pdf-n_pages", pdf->n_pages );
vips_image_set_int( out, VIPS_META_N_PAGES, pdf->n_pages );
for( i = 0; i < n_metadata; i++ ) {
VipsForeignLoadPdfMetadata *metadata =
&vips_foreign_load_pdf_metadata[i];
char *str;
if( (str = metadata->pdf_fetch( pdf->doc )) ) {
vips_image_set_string( out, metadata->field, str );
g_free( str );
}
}
/* We need pixels/mm for vips.
*/
res = pdf->dpi / 25.4;
vips_image_init_fields( out,
pdf->image.width, pdf->image.height,
4, VIPS_FORMAT_UCHAR,
VIPS_CODING_NONE, VIPS_INTERPRETATION_sRGB, res, res );
return( 0 );
}
static int
vips_foreign_load_pdf_header( VipsForeignLoad *load )
{
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( load );
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( load );
int top;
int i;
#ifdef DEBUG
printf( "vips_foreign_load_pdf_header: %p\n", pdf );
#endif /*DEBUG*/
pdf->n_pages = poppler_document_get_n_pages( pdf->doc );
/* @n == -1 means until the end of the doc.
*/
if( pdf->n == -1 )
pdf->n = pdf->n_pages - pdf->page_no;
if( pdf->page_no + pdf->n > pdf->n_pages ||
pdf->page_no < 0 ||
pdf->n <= 0 ) {
vips_error( class->nickname, "%s", _( "pages out of range" ) );
return( -1 );
}
/* Lay out the pages in our output image.
*/
if( !(pdf->pages = VIPS_ARRAY( pdf, pdf->n, VipsRect )) )
return( -1 );
top = 0;
pdf->image.left = 0;
pdf->image.top = 0;
pdf->image.width = 0;
pdf->image.height = 0;
for( i = 0; i < pdf->n; i++ ) {
double width;
double height;
if( vips_foreign_load_pdf_get_page( pdf, pdf->page_no + i ) )
return( -1 );
poppler_page_get_size( pdf->page, &width, &height );
pdf->pages[i].left = 0;
pdf->pages[i].top = top;
/* We do round to nearest, in the same way that vips_resize()
* does round to nearest. Without this, things like
* shrink-on-load will break.
*/
pdf->pages[i].width = VIPS_RINT( width * pdf->scale );
pdf->pages[i].height = VIPS_RINT( height * pdf->scale );
if( pdf->pages[i].width > pdf->image.width )
pdf->image.width = pdf->pages[i].width;
pdf->image.height += pdf->pages[i].height;
top += pdf->pages[i].height;
}
/* If all pages are the same height, we can tag this as a toilet roll
* image.
*/
for( i = 1; i < pdf->n; i++ )
if( pdf->pages[i].height != pdf->pages[0].height )
break;
if( vips_object_argument_isset( VIPS_OBJECT( pdf ), "n" ) )
vips_image_set_int( load->out,
VIPS_META_PAGE_HEIGHT, pdf->pages[0].height );
vips_foreign_load_pdf_set_image( pdf, load->out );
/* Convert the background to the image format.
*
* FIXME ... we probably should convert this to pre-multiplied BGRA
* to match the Cairo convention. See vips__cairo2rgba().
*/
if( !(pdf->ink = vips__vector_to_ink( class->nickname,
load->out,
VIPS_AREA( pdf->background )->data, NULL,
VIPS_AREA( pdf->background )->n )) )
return( -1 );
vips_source_minimise( pdf->source );
return( 0 );
}
static int
vips_foreign_load_pdf_generate( VipsRegion *or,
void *seq, void *a, void *b, gboolean *stop )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( a );
VipsRect *r = &or->valid;
int top;
int i;
int y;
/*
printf( "vips_foreign_load_pdf_generate: "
"left = %d, top = %d, width = %d, height = %d\n",
r->left, r->top, r->width, r->height );
*/
/* Poppler won't always paint the background.
*/
vips_region_paint_pel( or, r, pdf->ink );
/* Search through the pages we are drawing for the first containing
* this rect. This could be quicker, perhaps a binary search, but who
* cares.
*/
for( i = 0; i < pdf->n; i++ )
if( VIPS_RECT_BOTTOM( &pdf->pages[i] ) > r->top )
break;
top = r->top;
while( top < VIPS_RECT_BOTTOM( r ) ) {
VipsRect rect;
cairo_surface_t *surface;
cairo_t *cr;
vips_rect_intersectrect( r, &pdf->pages[i], &rect );
surface = cairo_image_surface_create_for_data(
VIPS_REGION_ADDR( or, rect.left, rect.top ),
CAIRO_FORMAT_ARGB32,
rect.width, rect.height,
VIPS_REGION_LSKIP( or ) );
cr = cairo_create( surface );
cairo_surface_destroy( surface );
cairo_scale( cr, pdf->scale, pdf->scale );
cairo_translate( cr,
(pdf->pages[i].left - rect.left) / pdf->scale,
(pdf->pages[i].top - rect.top) / pdf->scale );
/* poppler is single-threaded, but we don't need to lock since
* we're running inside a non-threaded tilecache.
*/
if( vips_foreign_load_pdf_get_page( pdf, pdf->page_no + i ) )
return( -1 );
poppler_page_render( pdf->page, cr );
cairo_destroy( cr );
top += rect.height;
i += 1;
}
/* Cairo makes pre-multipled BRGA, we must byteswap and unpremultiply.
*/
for( y = 0; y < r->height; y++ )
vips__cairo2rgba(
(guint32 *) VIPS_REGION_ADDR( or, r->left, r->top + y ),
r->width );
return( 0 );
}
static int
vips_foreign_load_pdf_load( VipsForeignLoad *load )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( load );
VipsImage **t = (VipsImage **)
vips_object_local_array( (VipsObject *) load, 2 );
#ifdef DEBUG
printf( "vips_foreign_load_pdf_load: %p\n", pdf );
#endif /*DEBUG*/
/* Read to this image, then cache to out, see below.
*/
t[0] = vips_image_new();
/* Don't minimise on ::minimise (end of computation): we support
* threaded read, and minimise will happen outside the cache lock.
*/
vips_foreign_load_pdf_set_image( pdf, t[0] );
if( vips_image_generate( t[0],
NULL, vips_foreign_load_pdf_generate, NULL, pdf, NULL ) )
return( -1 );
/* Don't use tilecache to keep the number of calls to
* pdf_page_render() low. Don't thread the cache, we rely on
* locking to keep pdf single-threaded. Use a large strip size to
* (again) keep the number of calls to page_render low.
*/
if( vips_linecache( t[0], &t[1],
"tile_height", VIPS_MIN( 5000, pdf->pages[0].height ),
NULL ) )
return( -1 );
if( vips_image_write( t[1], load->real ) )
return( -1 );
return( 0 );
}
static void
vips_foreign_load_pdf_class_init( VipsForeignLoadPdfClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
gobject_class->dispose = vips_foreign_load_pdf_dispose;
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
object_class->nickname = "pdfload_base";
object_class->description = _( "load PDF with libpoppler" );
object_class->build = vips_foreign_load_pdf_build;
load_class->get_flags_filename =
vips_foreign_load_pdf_get_flags_filename;
load_class->get_flags = vips_foreign_load_pdf_get_flags;
load_class->header = vips_foreign_load_pdf_header;
load_class->load = vips_foreign_load_pdf_load;
VIPS_ARG_INT( class, "page", 20,
_( "Page" ),
_( "Load this page from the file" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdf, page_no ),
0, 100000, 0 );
VIPS_ARG_INT( class, "n", 21,
_( "n" ),
_( "Load this many pages" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdf, n ),
-1, 100000, 1 );
VIPS_ARG_DOUBLE( class, "dpi", 22,
_( "DPI" ),
_( "Render at this DPI" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdf, dpi ),
0.001, 100000.0, 72.0 );
VIPS_ARG_DOUBLE( class, "scale", 23,
_( "Scale" ),
_( "Scale output by this factor" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdf, scale ),
0.001, 100000.0, 1.0 );
VIPS_ARG_BOXED( class, "background", 24,
_( "Background" ),
_( "Background value" ),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdf, background ),
VIPS_TYPE_ARRAY_DOUBLE );
}
static void
vips_foreign_load_pdf_init( VipsForeignLoadPdf *pdf )
{
pdf->dpi = 72.0;
pdf->scale = 1.0;
pdf->n = 1;
pdf->current_page = -1;
pdf->background = vips_array_double_newv( 1, 255.0 );
}
typedef struct _VipsForeignLoadPdfFile {
VipsForeignLoadPdf parent_object;
/* Filename for load.
*/
char *filename;
char *uri;
} VipsForeignLoadPdfFile;
typedef VipsForeignLoadPdfClass VipsForeignLoadPdfFileClass;
G_DEFINE_TYPE( VipsForeignLoadPdfFile, vips_foreign_load_pdf_file,
vips_foreign_load_pdf_get_type() );
static void
vips_foreign_load_pdf_file_dispose( GObject *gobject )
{
VipsForeignLoadPdfFile *file =
(VipsForeignLoadPdfFile *) gobject;
VIPS_FREE( file->uri );
G_OBJECT_CLASS( vips_foreign_load_pdf_file_parent_class )->
dispose( gobject );
}
static int
vips_foreign_load_pdf_file_header( VipsForeignLoad *load )
{
VipsForeignLoadPdfFile *file = (VipsForeignLoadPdfFile *) load;
VIPS_SETSTR( load->out->filename, file->filename );
return( VIPS_FOREIGN_LOAD_CLASS(
vips_foreign_load_pdf_file_parent_class )->header( load ) );
}
static const char *vips_foreign_pdf_suffs[] = {
".pdf",
NULL
};
static int
vips_foreign_load_pdf_file_build( VipsObject *object )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( object );
VipsForeignLoadPdfFile *file = (VipsForeignLoadPdfFile *) pdf;
#ifdef DEBUG
printf( "vips_foreign_load_pdf_file_build: %s\n", file->filename );
#endif /*DEBUG*/
if( file->filename ) {
char *path;
GError *error = NULL;
/* We need an absolute path for a URI.
*/
path = vips_realpath( file->filename );
if( !(file->uri = g_filename_to_uri( path, NULL, &error )) ) {
g_free( path );
vips_g_error( &error );
return( -1 );
}
g_free( path );
if( !(pdf->source =
vips_source_new_from_file( file->filename )) )
return( -1 );
}
return( VIPS_OBJECT_CLASS( vips_foreign_load_pdf_file_parent_class )->
build( object ) );
}
static void
vips_foreign_load_pdf_file_class_init(
VipsForeignLoadPdfFileClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsForeignClass *foreign_class = (VipsForeignClass *) class;
VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
gobject_class->dispose = vips_foreign_load_pdf_file_dispose;
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
object_class->nickname = "pdfload";
object_class->description = _( "load PDF from file" );
object_class->build = vips_foreign_load_pdf_file_build;
foreign_class->suffs = vips_foreign_pdf_suffs;
load_class->is_a = vips_foreign_load_pdf_is_a;
load_class->header = vips_foreign_load_pdf_file_header;
VIPS_ARG_STRING( class, "filename", 1,
_( "Filename" ),
_( "Filename to load from" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdfFile, filename ),
NULL );
}
static void
vips_foreign_load_pdf_file_init( VipsForeignLoadPdfFile *file )
{
}
typedef struct _VipsForeignLoadPdfBuffer {
VipsForeignLoadPdf parent_object;
/* Load from a buffer.
*/
VipsArea *buf;
} VipsForeignLoadPdfBuffer;
typedef VipsForeignLoadPdfClass VipsForeignLoadPdfBufferClass;
G_DEFINE_TYPE( VipsForeignLoadPdfBuffer, vips_foreign_load_pdf_buffer,
vips_foreign_load_pdf_get_type() );
static int
vips_foreign_load_pdf_buffer_build( VipsObject *object )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( object );
VipsForeignLoadPdfBuffer *buffer = (VipsForeignLoadPdfBuffer *) pdf;
if( buffer->buf &&
!(pdf->source = vips_source_new_from_memory(
VIPS_AREA( buffer->buf )->data,
VIPS_AREA( buffer->buf )->length )) )
return( -1 );
return( VIPS_OBJECT_CLASS( vips_foreign_load_pdf_buffer_parent_class )->
build( object ) );
}
static void
vips_foreign_load_pdf_buffer_class_init(
VipsForeignLoadPdfBufferClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
object_class->nickname = "pdfload_buffer";
object_class->description = _( "load PDF from buffer" );
object_class->build = vips_foreign_load_pdf_buffer_build;
load_class->is_a_buffer = vips_foreign_load_pdf_is_a_buffer;
VIPS_ARG_BOXED( class, "buffer", 1,
_( "Buffer" ),
_( "Buffer to load from" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdfBuffer, buf ),
VIPS_TYPE_BLOB );
}
static void
vips_foreign_load_pdf_buffer_init( VipsForeignLoadPdfBuffer *buffer )
{
}
typedef struct _VipsForeignLoadPdfSource {
VipsForeignLoadPdf parent_object;
VipsSource *source;
} VipsForeignLoadPdfSource;
typedef VipsForeignLoadPdfClass VipsForeignLoadPdfSourceClass;
G_DEFINE_TYPE( VipsForeignLoadPdfSource, vips_foreign_load_pdf_source,
vips_foreign_load_pdf_get_type() );
static int
vips_foreign_load_pdf_source_build( VipsObject *object )
{
VipsForeignLoadPdf *pdf = VIPS_FOREIGN_LOAD_PDF( object );
VipsForeignLoadPdfSource *source = (VipsForeignLoadPdfSource *) pdf;
if( source->source ) {
pdf->source = source->source;
g_object_ref( pdf->source );
}
return( VIPS_OBJECT_CLASS( vips_foreign_load_pdf_source_parent_class )->
build( object ) );
}
static gboolean
vips_foreign_load_pdf_source_is_a_source( VipsSource *source )
{
const unsigned char *p;
return( (p = vips_source_sniff( source, 4 )) &&
p[0] == '%' &&
p[1] == 'P' &&
p[2] == 'D' &&
p[3] == 'F' );
}
static void
vips_foreign_load_pdf_source_class_init(
VipsForeignLoadPdfSourceClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsForeignLoadClass *load_class = (VipsForeignLoadClass *) class;
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
object_class->nickname = "pdfload_source";
object_class->description = _( "load PDF from source" );
object_class->build = vips_foreign_load_pdf_source_build;
load_class->is_a_source = vips_foreign_load_pdf_source_is_a_source;
VIPS_ARG_OBJECT( class, "source", 1,
_( "Source" ),
_( "Source to load from" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadPdfSource, source ),
VIPS_TYPE_SOURCE );
}
static void
vips_foreign_load_pdf_source_init( VipsForeignLoadPdfSource *source )
{
}
#endif /*defined(HAVE_POPPLER)*/
/* Also used by the pdfium loader.
*/
gboolean
vips_foreign_load_pdf_is_a_buffer( const void *buf, size_t len )
{
const guchar *str = (const guchar *) buf;
if( len >= 4 &&
str[0] == '%' &&
str[1] == 'P' &&
str[2] == 'D' &&
str[3] == 'F' )
return( 1 );
return( 0 );
}
/* Also used by the pdfium loader.
*/
gboolean
vips_foreign_load_pdf_is_a( const char *filename )
{
unsigned char buf[4];
if( vips__get_bytes( filename, buf, 4 ) == 4 &&
vips_foreign_load_pdf_is_a_buffer( buf, 4 ) )
return( 1 );
return( 0 );
}
/**
* vips_pdfload:
* @filename: file to load
* @out: (out): output image
* @...: %NULL-terminated list of optional named arguments
*
* Optional arguments:
*
* * @page: %gint, load this page, numbered from zero
* * @n: %gint, load this many pages
* * @dpi: %gdouble, render at this DPI
* * @scale: %gdouble, scale render by this factor
* * @background: #VipsArrayDouble background colour
*
* Render a PDF file into a VIPS image. Rendering uses the libpoppler library
* and should be fast.
*
* The output image is always RGBA --- CMYK PDFs will be
* converted. If you need CMYK bitmaps, you should use vips_magickload()
* instead.
*
* Use @page to select a page to render, numbering from zero.
*
* Use @n to select the number of pages to render. The default is 1. Pages are
* rendered in a vertical column, with each individual page aligned to the
* left. Set to -1 to mean "until the end of the document". Use vips_grid()
* to change page layout.
*
* Use @dpi to set the rendering resolution. The default is 72. Alternatively,
* you can scale the rendering from the default 1 point == 1 pixel by
* setting @scale.
*
* Use @background to set the background RGBA colour. The default is 255
* (solid white), use eg. 0 for a transparent background.
*
* The operation fills a number of header fields with metadata, for example
* "pdf-author". They may be useful.
*
* This function only reads the image header and does not render any pixel
* data. Rendering occurs when pixels are accessed.
*
* See also: vips_image_new_from_file(), vips_magickload().
*
* Returns: 0 on success, -1 on error.
*/
int
vips_pdfload( const char *filename, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_call_split( "pdfload", ap, filename, out );
va_end( ap );
return( result );
}
/**
* vips_pdfload_buffer:
* @buf: (array length=len) (element-type guint8): memory area to load
* @len: (type gsize): size of memory area
* @out: (out): image to write
* @...: %NULL-terminated list of optional named arguments
*
* Optional arguments:
*
* * @page: %gint, load this page, numbered from zero
* * @n: %gint, load this many pages
* * @dpi: %gdouble, render at this DPI
* * @scale: %gdouble, scale render by this factor
* * @background: #VipsArrayDouble background colour
*
* Read a PDF-formatted memory buffer into a VIPS image. Exactly as
* vips_pdfload(), but read from memory.
*
* You must not free the buffer while @out is active. The
* #VipsObject::postclose signal on @out is a good place to free.
*
* See also: vips_pdfload().
*
* Returns: 0 on success, -1 on error.
*/
int
vips_pdfload_buffer( void *buf, size_t len, VipsImage **out, ... )
{
va_list ap;
VipsBlob *blob;
int result;
/* We don't take a copy of the data or free it.
*/
blob = vips_blob_new( NULL, buf, len );
va_start( ap, out );
result = vips_call_split( "pdfload_buffer", ap, blob, out );
va_end( ap );
vips_area_unref( VIPS_AREA( blob ) );
return( result );
}
/**
* vips_pdfload_source:
* @source: source to load from
* @out: (out): image to write
* @...: %NULL-terminated list of optional named arguments
*
* Optional arguments:
*
* * @page: %gint, load this page, numbered from zero
* * @n: %gint, load this many pages
* * @dpi: %gdouble, render at this DPI
* * @scale: %gdouble, scale render by this factor
* * @background: #VipsArrayDouble background colour
*
* Exactly as vips_pdfload(), but read from a source.
*
* See also: vips_pdfload()
*
* Returns: 0 on success, -1 on error.
*/
int
vips_pdfload_source( VipsSource *source, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_call_split( "pdfload_source", ap, source, out );
va_end( ap );
return( result );
}
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