kfaximage.cpp

okular

/* 
   This file is part of KDE FAX image library
   Copyright (c) 2005 Helge Deller <[e-mail]>

   based on Frank D. Cringle's viewfax package
   Copyright (C) 1990, 1995  Frank D. Cringle.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License version 2 as published by the Free Software Foundation.
   
   This library 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
   Library General Public License for more details.
   
   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/

#include <config.h>

#include <stdlib.h>

#include <qimage.h>
#include <qfile.h>

#include <kglobal.h>
#include <klocale.h>

#include "faxexpand.h"
#include "kfaximage.h"
#include "kdebug.h"

static const char FAXMAGIC[]   = "\000PC Research, Inc\000\000\000\000\000\000";
static const char littleTIFF[] = "\x49\x49\x2a\x00";
static const char bigTIFF[]    = "\x4d\x4d\x00\x2a";

KFaxImage::KFaxImage( const QString &filename, QObject *parent, const char *name )
   : QObject(parent)
{
  setObjectName(QLatin1String(name));
  KGlobal::locale()->insertCatalog( QString::fromLatin1("libkfaximage") );
  loadImage(filename);
}

KFaxImage::~KFaxImage()
{ }

bool KFaxImage::loadImage( const QString &filename )
{
  reset();

  m_filename = filename;
  m_errorString = QString::null;

  if (m_filename.isEmpty())
	return false;

  int ok = notetiff();
  if (!ok) {
	reset();
  }
  return ok == 1;
}

void KFaxImage::reset()
{
  fax_init_tables();
  qDeleteAll(m_pagenodes);
  m_pagenodes.clear();
  // do not reset m_errorString and m_filename, since 
  // they may be needed by calling application 
}

QImage KFaxImage::page( int pageNr )
{
  if (pageNr < 0 || pageNr >= numPages()) {
    kDebug() << "KFaxImage::page() called with invalid page number\n";
    return QImage();
  }
  pagenode *pn = m_pagenodes.at(pageNr);
  GetImage(pn);
  return pn->image;
}

QPoint KFaxImage::page_dpi( int pageNr )
{
  if (pageNr < 0 || pageNr >= numPages()) {
    kDebug() << "KFaxImage::page_dpi() called with invalid page number\n";
    return QPoint(0,0);
  }
  pagenode *pn = m_pagenodes.at(pageNr);
  GetImage(pn);
  return pn->dpi;
}

QSize KFaxImage::page_size( int pageNr )
{
  if (pageNr < 0 || pageNr >= numPages()) {
    kDebug() << "KFaxImage::page_size() called with invalid page number\n";
    return QSize(0,0);
  }
  pagenode *pn = m_pagenodes.at(pageNr);
  GetImage(pn);
  return pn->size;
}


pagenode *KFaxImage::AppendImageNode(int type)
{
    pagenode *pn = new pagenode();
    if (pn) {
	pn->type = type;
        pn->expander = g31expand;
	pn->strips = NULL;
	pn->size = QSize(1728,2339);
	pn->vres = -1;
	pn->dpi = KFAX_DPI_FINE;
	m_pagenodes.append(pn);
    }
    return pn;
}

bool KFaxImage::NewImage(pagenode *pn, int w, int h)
{
    pn->image = QImage( w, h, 1, 2, QImage::systemByteOrder() );
    pn->image.setColor(0, qRgb(255,255,255));
    pn->image.setColor(1, qRgb(0,0,0));
    pn->data = (quint16*) pn->image.bits();
    pn->bytes_per_line = pn->image.bytesPerLine();
    pn->dpi = KFAX_DPI_FINE;

    return !pn->image.isNull();
}

void KFaxImage::FreeImage(pagenode *pn)
{
    pn->image = QImage();
    pn->data = NULL;
    pn->bytes_per_line = 0;
}

void KFaxImage::kfaxerror(const QString& error)
{
    m_errorString = error;
    kError() << "kfaxerror: " << error << endl;
}


/* Enter an argument in the linked list of pages */
pagenode *
KFaxImage::notefile(int type)
{
    pagenode *newnode = new pagenode();
    newnode->type = type;
    newnode->size = QSize(1728,0);
    return newnode;
}

static t32bits
get4(unsigned char *p, QImage::Endian endian)
{
    return (endian == QImage::BigEndian) 
	? (p[0]<<24)|(p[1]<<16)|(p[2]<<8)|p[3] :
	   p[0]|(p[1]<<8)|(p[2]<<16)|(p[3]<<24);
}

static int
get2(unsigned char *p, QImage::Endian endian)
{
    return (endian == QImage::BigEndian) ? (p[0]<<8)|p[1] : p[0]|(p[1]<<8);
}

/* generate pagenodes for the images in a tiff file */
int
KFaxImage::notetiff()
{
#define SC(x) (char *)(x)
    unsigned char header[8];
    QImage::Endian endian;
    t32bits IFDoff;
    pagenode *pn = NULL;
    QString str;

    QFile file(filename());
    if (!file.open(QIODevice::ReadOnly)) {
	kfaxerror(i18n("Unable to open file for reading."));
	return 0;
    }

    if (file.read(SC(header), 8) != 8) {
	kfaxerror(i18n("Unable to read file header (file too short)."));
	return 0;
    }
    if (memcmp(header, &littleTIFF, 4) == 0)
	endian = QImage::LittleEndian;
    else if (memcmp(header, &bigTIFF, 4) == 0)
	endian = QImage::BigEndian;
    else {
 maybe_RAW_FAX:
        kfaxerror(i18n("This is not a TIFF FAX file."));
        // AppendImageNode(FAX_RAW);
	return 0;
    }
    IFDoff = get4(header+4, endian);
    if (IFDoff & 1) {
	goto maybe_RAW_FAX;
    }
    do {			/* for each page */
	unsigned char buf[8];
	unsigned char *dir = NULL , *dp = NULL;
	int ndirent;
	pixnum iwidth = 1728;
	pixnum iheight = 2339;
	int inverse = false;
	int lsbfirst = 0;
	int t4opt = 0, comp = 0;
	int orient = TURN_NONE;
	int yres = 196; /* 98.0 */
	struct strip *strips = NULL;
	unsigned int rowsperstrip = 0;
	t32bits nstrips = 1;

	if (!file.seek(IFDoff)) {
	realbad:
	  kfaxerror( i18n("Invalid or incomplete TIFF file.") );
	bad:
	    if (strips)
		free(strips);
	    if (dir)
		free(dir);
	    file.close();
	    return 1;
	}
	if (file.read(SC(buf), 2) != 2)
	    goto realbad;
	ndirent = get2(buf, endian);
        int len = 12*ndirent+4;
	dir = (unsigned char *) malloc(len);
	if (file.read(SC(dir), len) != len)
	    goto realbad;
	for (dp = dir; ndirent; ndirent--, dp += 12) {
	    /* for each directory entry */
	    int tag, ftype;
	    t32bits count, value = 0;
	    tag = get2(dp, endian);
	    ftype = get2(dp+2, endian);
	    count = get4(dp+4, endian);
	    switch(ftype) {	/* value is offset to list if count*size > 4 */
	    case 3:		/* short */
		value = get2(dp+8, endian);
		break;
	    case 4:		/* long */
		value = get4(dp+8, endian);
		break;
	    case 5:		/* offset to rational */
		value = get4(dp+8, endian);
		break;
	    }
	    switch(tag) {
	    case 256:		/* ImageWidth */
		iwidth = value;
		break;
	    case 257:		/* ImageLength */
		iheight = value;
		break;
	    case 259:		/* Compression */
		comp = value;
		break;
	    case 262:		/* PhotometricInterpretation */
		inverse ^= (value == 1);
		break;
	    case 266:		/* FillOrder */
		lsbfirst = (value == 2);
		break;
	    case 273:		/* StripOffsets */
		nstrips = count;
		strips = (struct strip *) malloc(count * sizeof *strips);
		if (count == 1 || (count == 2 && ftype == 3)) {
		    strips[0].offset = value;
		    if (count == 2)
			strips[1].offset = get2(dp+10, endian);
		    break;
		}
		if (!file.seek(value))
		    goto realbad;
		for (count = 0; count < nstrips; count++) {
		    if (file.read(SC(buf), (ftype == 3) ? 2 : 4) <= 0)
			goto realbad;
		    strips[count].offset = (ftype == 3) ?
			get2(buf, endian) : get4(buf, endian);
		}
		break;
	    case 274:		/* Orientation */
		switch(value) {
		default:	/* row0 at top,    col0 at left   */
		    orient = 0;
		    break;
		case 2:		/* row0 at top,    col0 at right  */
		    orient = TURN_M;
		    break;
		case 3:		/* row0 at bottom, col0 at right  */
		    orient = TURN_U;
		    break;
		case 4:		/* row0 at bottom, col0 at left   */
		    orient = TURN_U|TURN_M;
		    break;
		case 5:		/* row0 at left,   col0 at top    */
		    orient = TURN_M|TURN_L;
		    break;
		case 6:		/* row0 at right,  col0 at top    */
		    orient = TURN_U|TURN_L;
		    break;
		case 7:		/* row0 at right,  col0 at bottom */
		    orient = TURN_U|TURN_M|TURN_L;
		    break;
		case 8:		/* row0 at left,   col0 at bottom */
		    orient = TURN_L;
		    break;
		}
		break;
	    case 278:		/* RowsPerStrip */
		rowsperstrip = value;	
		break;
	    case 279:		/* StripByteCounts */
		if (count != nstrips) {
		  str = i18n("In file %1\nStripsPerImage tag 273=%2,tag279=%3\n",
			      filename(), nstrips, count);
		  kfaxerror(str);
		  goto realbad;
		}
		if (count == 1 || (count == 2 && ftype == 3)) {