mirror of
https://github.com/tesseract-ocr/tesseract.git
synced 2024-12-11 23:19:04 +08:00
864b2f6d80
git-svn-id: https://tesseract-ocr.googlecode.com/svn/trunk@1042 d0cd1f9f-072b-0410-8dd7-cf729c803f20
752 lines
22 KiB
C++
752 lines
22 KiB
C++
// Include automatically generated configuration file if running autoconf.
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#ifdef HAVE_CONFIG_H
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#include "config_auto.h"
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#endif
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#include "baseapi.h"
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#include "renderer.h"
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#include "math.h"
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#include "strngs.h"
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#include "cube_utils.h"
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#include "allheaders.h"
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#if !defined(VERSION)
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#include "version.h"
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#endif
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#ifdef _MSC_VER
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#include "mathfix.h"
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#endif
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namespace tesseract {
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// Use for PDF object fragments. Must be large enough
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// to hold a colormap with 256 colors in the verbose
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// PDF representation.
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const int kBasicBufSize = 2048;
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// If the font is 10 pts, nominal character width is 5 pts
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const int kCharWidth = 2;
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/**********************************************************************
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* PDF Renderer interface implementation
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**********************************************************************/
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TessPDFRenderer::TessPDFRenderer(const char *datadir)
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: TessResultRenderer("PDF", "pdf") {
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obj_ = 0;
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datadir_ = datadir;
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offsets_.push_back(0);
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}
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void TessPDFRenderer::AppendPDFObjectDIY(size_t objectsize) {
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offsets_.push_back(objectsize + offsets_.back());
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obj_++;
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}
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void TessPDFRenderer::AppendPDFObject(const char *data) {
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AppendPDFObjectDIY(strlen(data));
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AppendString((const char *)data);
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}
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// Helper function to prevent us from accidentaly writing
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// scientific notation to an HOCR or PDF file. Besides, three
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// decimal points are all you really need.
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double prec(double x) {
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double kPrecision = 1000.0;
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double a = round(x * kPrecision) / kPrecision;
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if (a == -0)
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return 0;
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return a;
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}
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long dist2(int x1, int y1, int x2, int y2) {
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return (x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1);
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}
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char* TessPDFRenderer::GetPDFTextObjects(TessBaseAPI* api,
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double width, double height,
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int page_number) {
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double ppi = api->GetSourceYResolution();
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STRING pdf_str("");
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double old_x = 0.0, old_y = 0.0;
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int old_pointsize = 0;
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// TODO(jbreiden) Slightly cleaner from an abstraction standpoint
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// if this were to live inside a separate text object.
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pdf_str += "q ";
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pdf_str.add_str_double("", prec(width));
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pdf_str += " 0 0 ";
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pdf_str.add_str_double("", prec(height));
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pdf_str += " 0 0 cm /Im1 Do Q\n";
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ResultIterator *res_it = api->GetIterator();
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while (!res_it->Empty(RIL_BLOCK)) {
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if (res_it->IsAtBeginningOf(RIL_BLOCK)) {
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pdf_str += "BT\n3 Tr\n"; // Begin text object, use invisible ink
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old_pointsize = 0.0; // Every block will declare its font
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}
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int line_x1, line_y1, line_x2, line_y2;
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if (res_it->IsAtBeginningOf(RIL_TEXTLINE)) {
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res_it->Baseline(RIL_TEXTLINE,
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&line_x1, &line_y1, &line_x2, &line_y2);
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double rise = abs(line_y2 - line_y1) * 72 / ppi;
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double run = abs(line_x2 - line_x1) * 72 / ppi;
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// There are some really stupid PDF viewers in the wild, such as
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// 'Preview' which ships with the Mac. They might do a better
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// job with text selection and highlighting when given perfectly
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// straight text instead of very slightly tilted text. I chose
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// this threshold large enough to absorb noise, but small enough
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// that lines probably won't cross each other if the whole page
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// is tilted at almost exactly the clipping threshold.
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if (rise < 2.0 && 2.0 < run)
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line_y1 = line_y2 = (line_y1 + line_y2) / 2;
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}
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if (res_it->Empty(RIL_WORD)) {
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res_it->Next(RIL_WORD);
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continue;
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}
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int word_x1, word_y1, word_x2, word_y2;
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res_it->Baseline(RIL_WORD, &word_x1, &word_y1, &word_x2, &word_y2);
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// The critical one is writing_direction
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tesseract::Orientation orientation;
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tesseract::WritingDirection writing_direction;
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tesseract::TextlineOrder textline_order;
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float deskew_angle;
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res_it->Orientation(&orientation, &writing_direction,
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&textline_order, &deskew_angle);
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// Unlike Tesseract, we always want the word baseline in reading order.
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if (writing_direction == WRITING_DIRECTION_RIGHT_TO_LEFT) {
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Swap(&word_x1, &word_x2);
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Swap(&word_y1, &word_y2);
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}
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// Viewers like evince can get really confused during copy-paste
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// when the baseline wanders around. I've decided to force every
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// word to match the (straight) baseline. The math below is just
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// projecting the word origin onto the baseline. All numbers are
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// in the native PDF coordinate system, which has the origin in
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// the bottom left and the unit is points, which is 1/72 inch.
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double word_length;
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double x, y;
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{
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int px = word_x1;
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int py = word_y1;
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double l2 = dist2(line_x1, line_y1, line_x2, line_y2);
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if (l2 == 0) {
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x = line_x1;
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y = line_y1;
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} else {
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double t = ((px - line_x2) * (line_x2 - line_x1) +
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(py - line_y2) * (line_y2 - line_y1)) / l2;
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x = line_x2 + t * (line_x2 - line_x1);
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y = line_y2 + t * (line_y2 - line_y1);
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}
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word_length = sqrt(static_cast<double>(dist2(word_x1, word_y1,
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word_x2, word_y2)));
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word_length = word_length * 72.0 / ppi;
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x = x * 72 / ppi;
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y = height - (y * 72.0 / ppi);
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}
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int pointsize = 0;
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if (res_it->IsAtBeginningOf(RIL_TEXTLINE)) {
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// Calculate the rotation angle in the PDF cooordinate system,
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// which has the origin in the bottom left. The Tesseract
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// coordinate system has the origin in the upper left.
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//
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// PDF is kind of a like turtle graphics, and we orient the
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// turtle (errr... initial cursor position) with an affine
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// transformation.
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//
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// Rotate RTL Translate
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//
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// [ x' y' 1 ] = [ x y 1 ] [ cos𝜃 -sin𝜃 0 ] [ -1 0 0 ] [ 1 0 0 ]
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// [ sin𝜃 cos𝜃 0 ] [ 0 1 0 ] [ 0 1 0 ]
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// [ 0 0 1 ] [ 0 0 1 ] [ x y 1 ]
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//
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double theta = atan2(static_cast<double>(line_y1 - line_y2),
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static_cast<double>(line_x2 - line_x1));
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double a, b, c, d;
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a = cos(theta);
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b = sin(theta);
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c = -sin(theta);
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d = cos(theta);
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switch(writing_direction) {
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case WRITING_DIRECTION_RIGHT_TO_LEFT:
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a = -a;
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b = -b;
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c = -c;
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break;
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case WRITING_DIRECTION_TOP_TO_BOTTOM:
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// TODO(jbreiden) Consider switching PDF writing mode to vertical.
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break;
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default:
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break;
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}
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pdf_str.add_str_double("", prec(a)); // . This affine matrix
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pdf_str.add_str_double(" ", prec(b)); // . sets the coordinate
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pdf_str.add_str_double(" ", prec(c)); // . system for all
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pdf_str.add_str_double(" ", prec(d)); // . text in the entire
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pdf_str.add_str_double(" ", prec(x)); // . line.
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pdf_str.add_str_double(" ", prec(y)); // .
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pdf_str += (" Tm "); // Place cursor absolutely
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} else {
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double offset = sqrt(static_cast<double>(dist2(old_x, old_y, x, y)));
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pdf_str.add_str_double(" ", prec(offset)); // Delta x in pts
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pdf_str.add_str_double(" ", 0); // Delta y in pts
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pdf_str += (" Td "); // Relative moveto
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}
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old_x = x;
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old_y = y;
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// Adjust font size on a per word granularity. Pay attention to
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// pointsize, old_pointsize, and pdf_str.
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{
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bool bold, italic, underlined, monospace, serif, smallcaps;
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int font_id;
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res_it->WordFontAttributes(&bold, &italic, &underlined, &monospace,
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&serif, &smallcaps, &pointsize, &font_id);
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if (pointsize != old_pointsize) {
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char textfont[20];
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snprintf(textfont, sizeof(textfont), "/f-0-0 %d Tf ", pointsize);
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pdf_str += textfont;
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old_pointsize = pointsize;
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}
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}
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bool last_word_in_line = res_it->IsAtFinalElement(RIL_TEXTLINE, RIL_WORD);
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bool last_word_in_block = res_it->IsAtFinalElement(RIL_BLOCK, RIL_WORD);
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STRING pdf_word("");
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int pdf_word_len = 0;
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do {
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const char *grapheme = res_it->GetUTF8Text(RIL_SYMBOL);
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if (grapheme && grapheme[0] != 0) {
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// TODO(jbreiden) Do a real UTF-16BE conversion
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// http://en.wikipedia.org/wiki/UTF-16#Example_UTF-16_encoding_procedure
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string_32 utf32;
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CubeUtils::UTF8ToUTF32(grapheme, &utf32);
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char utf16[20];
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for (int i = 0; i < static_cast<int>(utf32.length()); i++) {
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snprintf(utf16, sizeof(utf16), "<%04X>", utf32[i]);
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pdf_word += utf16;
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pdf_word_len++;
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}
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}
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delete []grapheme;
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res_it->Next(RIL_SYMBOL);
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} while (!res_it->Empty(RIL_BLOCK) && !res_it->IsAtBeginningOf(RIL_WORD));
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if (word_length > 0 && pdf_word_len > 0 && pointsize > 0) {
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double h_stretch =
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kCharWidth * prec(100.0 * word_length / (pointsize * pdf_word_len));
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pdf_str.add_str_double("", h_stretch);
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pdf_str += " Tz"; // horizontal stretch
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pdf_str += " [ ";
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pdf_str += pdf_word; // UTF-16BE representation
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pdf_str += " ] TJ"; // show the text
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}
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if (last_word_in_line) {
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pdf_str += " \n";
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}
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if (last_word_in_block) {
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pdf_str += "ET\n"; // end the text object
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}
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}
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char *ret = new char[pdf_str.length() + 1];
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strcpy(ret, pdf_str.string());
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delete res_it;
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return ret;
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}
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bool TessPDFRenderer::BeginDocumentHandler() {
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char buf[kBasicBufSize];
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snprintf(buf, sizeof(buf),
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"%%PDF-1.5\n"
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"%%%c%c%c%c\n",
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0xDE, 0xAD, 0xBE, 0xEB);
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AppendPDFObject(buf);
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// CATALOG
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snprintf(buf, sizeof(buf),
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"1 0 obj\n"
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"<<\n"
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" /Type /Catalog\n"
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" /Pages %ld 0 R\n"
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">>\n"
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"endobj\n", 2L);
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AppendPDFObject(buf);
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// We are reserving object #2 for the /Pages
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// object, which I am going to create and write
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// at the end of the PDF file.
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AppendPDFObject("");
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// TYPE0 FONT
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snprintf(buf, sizeof(buf),
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"3 0 obj\n"
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"<<\n"
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" /BaseFont /GlyphLessFont\n"
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" /DescendantFonts [ %ld 0 R ]\n"
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" /Encoding /Identity-H\n"
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" /Subtype /Type0\n"
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" /ToUnicode %ld 0 R\n"
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" /Type /Font\n"
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">>\n"
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"endobj\n",
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4L, // CIDFontType2 font
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5L // ToUnicode
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);
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AppendPDFObject(buf);
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// CIDFONTTYPE2
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snprintf(buf, sizeof(buf),
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"4 0 obj\n"
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"<<\n"
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" /BaseFont /GlyphLessFont\n"
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" /CIDToGIDMap /Identity\n"
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" /CIDSystemInfo\n"
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" <<\n"
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" /Ordering (Identity)\n"
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" /Registry (Adobe)\n"
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" /Supplement 0\n"
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" >>\n"
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" /FontDescriptor %ld 0 R\n"
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" /Subtype /CIDFontType2\n"
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" /Type /Font\n"
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" /DW %d\n"
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">>\n"
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"endobj\n",
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6L, // Font descriptor
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1000 / kCharWidth);
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AppendPDFObject(buf);
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const char *stream =
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"/CIDInit /ProcSet findresource begin\n"
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"12 dict begin\n"
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"begincmap\n"
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"/CIDSystemInfo\n"
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"<<\n"
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" /Registry (Adobe)\n"
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" /Ordering (UCS)\n"
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" /Supplement 0\n"
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">> def\n"
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"/CMapName /Adobe-Identify-UCS def\n"
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"/CMapType 2 def\n"
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"1 begincodespacerange\n"
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"<0000> <FFFF>\n"
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"endcodespacerange\n"
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"1 beginbfrange\n"
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"<0000> <FFFF> <0000>\n"
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"endbfrange\n"
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"endcmap\n"
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"CMapName currentdict /CMap defineresource pop\n"
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"end\n"
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"end\n";
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// TOUNICODE
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snprintf(buf, sizeof(buf),
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"5 0 obj\n"
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"<< /Length %lu >>\n"
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"stream\n"
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"%s"
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"endstream\n"
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"endobj\n", (unsigned long) strlen(stream), stream);
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AppendPDFObject(buf);
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// FONT DESCRIPTOR
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const int kCharHeight = 2; // Effect: highlights are half height
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snprintf(buf, sizeof(buf),
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"6 0 obj\n"
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"<<\n"
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" /Ascent %d\n"
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" /CapHeight %d\n"
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" /Descent -1\n" // Spec says must be negative
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" /Flags 5\n" // FixedPitch + Symbolic
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" /FontBBox [ 0 0 %d %d ]\n"
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" /FontFile2 %ld 0 R\n"
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" /FontName /GlyphLessFont\n"
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" /ItalicAngle 0\n"
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" /StemV 80\n"
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" /Type /FontDescriptor\n"
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">>\n"
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"endobj\n",
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1000 / kCharHeight,
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1000 / kCharHeight,
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1000 / kCharWidth,
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1000 / kCharHeight,
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7L // Font data
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);
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AppendPDFObject(buf);
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snprintf(buf, sizeof(buf), "%s/pdf.ttf", datadir_);
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FILE *fp = fopen(buf, "rb");
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if (!fp)
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return false;
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fseek(fp, 0, SEEK_END);
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long int size = ftell(fp);
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fseek(fp, 0, SEEK_SET);
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char *buffer = new char[size];
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fread(buffer, 1, size, fp);
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fclose(fp);
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// FONTFILE2
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snprintf(buf, sizeof(buf),
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"7 0 obj\n"
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"<<\n"
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" /Length %ld\n"
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" /Length1 %ld\n"
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">>\n"
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"stream\n", size, size);
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AppendString(buf);
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size_t objsize = strlen(buf);
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AppendData(buffer, size);
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objsize += size;
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snprintf(buf, sizeof(buf),
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"endstream\n"
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"endobj\n");
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AppendString(buf);
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objsize += strlen(buf);
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AppendPDFObjectDIY(objsize);
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return true;
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}
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// TODO(jbreiden) I hear that you can pull the flate stream out
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// of a PNG file and, by mentioning the predictor in the PDF object,
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// make most of them work without transcoding. If so that's a big win
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// versus what we do now. Try it out.
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bool TessPDFRenderer::fileToPDFObj(char *filename, long int objnum,
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char **pdf_object,
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long int *pdf_object_size) {
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char b1[kBasicBufSize];
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char b2[kBasicBufSize];
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if (!pdf_object_size || !pdf_object)
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return false;
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*pdf_object = NULL;
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*pdf_object_size = 0;
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if (!filename)
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return false;
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FILE *fp = fopen(filename, "rb");
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if (!fp)
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return false;
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int format;
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findFileFormatStream(fp, &format);
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if (format != IFF_JFIF_JPEG) {
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fclose(fp);
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return false;
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}
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fseek(fp, 0, SEEK_END);
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long int jpeg_size = ftell(fp);
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fseek(fp, 0, SEEK_SET);
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int spp, cmyk, w, h;
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freadHeaderJpeg(fp, &w, &h, &spp, NULL, &cmyk);
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const char *colorspace;
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switch (spp) {
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case 1:
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colorspace = "/DeviceGray";
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break;
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case 3:
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colorspace = "/DeviceRGB";
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break;
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case 4:
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if (cmyk)
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colorspace = "/DeviceCMYK";
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else
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return false;
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break;
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default:
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return false;
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}
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// IMAGE
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snprintf(b1, sizeof(b1),
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"%ld 0 obj\n"
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"<<\n"
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" /Length %ld\n"
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" /Subtype /Image\n"
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" /ColorSpace %s\n"
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" /Width %d\n"
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" /Height %d\n"
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" /BitsPerComponent 8\n"
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" /Filter /DCTDecode\n"
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">>\n"
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"stream\n", objnum, jpeg_size,
|
|
colorspace, w, h);
|
|
size_t b1_len = strlen(b1);
|
|
|
|
snprintf(b2, sizeof(b2),
|
|
"\n"
|
|
"endstream\n"
|
|
"endobj\n");
|
|
size_t b2_len = strlen(b2);
|
|
|
|
*pdf_object_size = b1_len + jpeg_size + b2_len;
|
|
*pdf_object = new char[*pdf_object_size];
|
|
if (!pdf_object)
|
|
return false;
|
|
memcpy(*pdf_object, b1, b1_len);
|
|
if (static_cast<int>(fread(*pdf_object + b1_len, 1, jpeg_size, fp)) !=
|
|
jpeg_size) {
|
|
delete[] pdf_object;
|
|
return false;
|
|
}
|
|
memcpy(*pdf_object + b1_len + jpeg_size, b2, b2_len);
|
|
fclose(fp);
|
|
return true;
|
|
}
|
|
|
|
bool TessPDFRenderer::pixToPDFObj(Pix *pix, long int objnum,
|
|
char **pdf_object,
|
|
long int *pdf_object_size) {
|
|
if (!pdf_object_size || !pdf_object)
|
|
return false;
|
|
*pdf_object = NULL;
|
|
*pdf_object_size = 0;
|
|
char b0[kBasicBufSize];
|
|
char b1[kBasicBufSize * 2];
|
|
char b2[kBasicBufSize];
|
|
L_COMP_DATA *cid;
|
|
int encoding_type;
|
|
const int kJpegQuality = 85;
|
|
if (selectDefaultPdfEncoding(pix, &encoding_type) != 0)
|
|
return false;
|
|
if (pixGenerateCIData(pix, encoding_type, kJpegQuality, 0, &cid) != 0)
|
|
return false;
|
|
|
|
const char *filter;
|
|
switch(encoding_type) {
|
|
case L_FLATE_ENCODE:
|
|
filter = "/FlateDecode";
|
|
break;
|
|
case L_JPEG_ENCODE:
|
|
filter = "/DCTDecode";
|
|
break;
|
|
case L_G4_ENCODE:
|
|
filter = "/CCITTFaxDecode";
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
const char *colorspace;
|
|
if (cid->ncolors > 0) {
|
|
snprintf(b0, sizeof(b0), "[ /Indexed /DeviceRGB %d %s ]",
|
|
cid->ncolors - 1, cid->cmapdatahex);
|
|
colorspace = b0;
|
|
} else {
|
|
switch (cid->spp) {
|
|
case 1:
|
|
colorspace = "/DeviceGray";
|
|
break;
|
|
case 3:
|
|
colorspace = "/DeviceRGB";
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
snprintf(b1, sizeof(b1),
|
|
"%ld 0 obj\n"
|
|
"<<\n"
|
|
" /Length %lu\n"
|
|
" /Subtype /Image\n"
|
|
" /ColorSpace %s\n"
|
|
" /Width %d\n"
|
|
" /Height %d\n"
|
|
" /BitsPerComponent %d\n"
|
|
" /Filter %s\n"
|
|
" /DecodeParms\n"
|
|
" <<\n"
|
|
" /K -1\n"
|
|
" /Columns %d\n"
|
|
" >>\n"
|
|
">>\n"
|
|
"stream\n",
|
|
objnum, (unsigned long) cid->nbytescomp, colorspace,
|
|
cid->w, cid->h, cid->bps, filter, cid->w);
|
|
size_t b1_len = strlen(b1);
|
|
|
|
snprintf(b2, sizeof(b2),
|
|
"\n"
|
|
"endstream\n"
|
|
"endobj\n");
|
|
size_t b2_len = strlen(b2);
|
|
|
|
*pdf_object_size = b1_len + cid->nbytescomp + b2_len;
|
|
*pdf_object = new char[*pdf_object_size];
|
|
if (!pdf_object)
|
|
return false;
|
|
memcpy(*pdf_object, b1, b1_len);
|
|
memcpy(*pdf_object + b1_len, cid->datacomp, cid->nbytescomp);
|
|
memcpy(*pdf_object + b1_len + cid->nbytescomp, b2, b2_len);
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
bool TessPDFRenderer::AddImageHandler(TessBaseAPI* api) {
|
|
char buf[kBasicBufSize];
|
|
Pix *pix = api->GetInputImage();
|
|
char *filename = (char *)api->GetInputName();
|
|
int ppi = api->GetSourceYResolution();
|
|
if (!pix || ppi <= 0)
|
|
return false;
|
|
double width = pixGetWidth(pix) * 72.0 / ppi;
|
|
double height = pixGetHeight(pix) * 72.0 / ppi;
|
|
|
|
// PAGE
|
|
snprintf(buf, sizeof(buf),
|
|
"%ld 0 obj\n"
|
|
"<<\n"
|
|
" /Type /Page\n"
|
|
" /Parent %ld 0 R\n"
|
|
" /MediaBox [0 0 %.2f %.2f]\n"
|
|
" /Contents %ld 0 R\n"
|
|
" /Resources\n"
|
|
" <<\n"
|
|
" /XObject << /Im1 %ld 0 R >>\n"
|
|
" /ProcSet [ /PDF /Text /ImageB /ImageI /ImageC ]\n"
|
|
" /Font << /f-0-0 %ld 0 R >>\n"
|
|
" >>\n"
|
|
">>\n"
|
|
"endobj\n",
|
|
obj_,
|
|
2L, // Pages object
|
|
width,
|
|
height,
|
|
obj_ + 1, // Contents object
|
|
obj_ + 2, // Image object
|
|
3L); // Type0 Font
|
|
pages_.push_back(obj_);
|
|
AppendPDFObject(buf);
|
|
|
|
// CONTENTS
|
|
char* pdftext = GetPDFTextObjects(api, width, height, imagenum());
|
|
long pdftext_len = strlen(pdftext);
|
|
unsigned char *pdftext_casted = reinterpret_cast<unsigned char *>(pdftext);
|
|
size_t len;
|
|
unsigned char *comp_pdftext =
|
|
zlibCompress(pdftext_casted,
|
|
pdftext_len,
|
|
&len);
|
|
long comp_pdftext_len = len;
|
|
snprintf(buf, sizeof(buf),
|
|
"%ld 0 obj\n"
|
|
"<<\n"
|
|
" /Length %ld /Filter /FlateDecode\n"
|
|
">>\n"
|
|
"stream\n", obj_, comp_pdftext_len);
|
|
AppendString(buf);
|
|
long objsize = strlen(buf);
|
|
AppendData(reinterpret_cast<char *>(comp_pdftext), comp_pdftext_len);
|
|
objsize += comp_pdftext_len;
|
|
lept_free(comp_pdftext);
|
|
|
|
delete[] pdftext;
|
|
snprintf(buf, sizeof(buf),
|
|
"endstream\n"
|
|
"endobj\n");
|
|
AppendString(buf);
|
|
objsize += strlen(buf);
|
|
AppendPDFObjectDIY(objsize);
|
|
|
|
char *pdf_object;
|
|
if (!fileToPDFObj(filename, obj_, &pdf_object, &objsize)) {
|
|
if (!pixToPDFObj(pix, obj_, &pdf_object, &objsize)) {
|
|
return false;
|
|
}
|
|
}
|
|
AppendData(pdf_object, objsize);
|
|
AppendPDFObjectDIY(objsize);
|
|
delete[] pdf_object;
|
|
return true;
|
|
}
|
|
|
|
|
|
bool TessPDFRenderer::EndDocumentHandler() {
|
|
char buf[kBasicBufSize];
|
|
|
|
// We reserved the /Pages object number early, so that the /Page
|
|
// objects could refer to their parent. We finally have enough
|
|
// information to go fill it in. Using lower level calls to manipulate
|
|
// the offset record in two spots, because we are placing objects
|
|
// out of order in the file.
|
|
|
|
// PAGES
|
|
const long int kPagesObjectNumber = 2;
|
|
offsets_[kPagesObjectNumber] = offsets_.back(); // manipulation #1
|
|
snprintf(buf, sizeof(buf),
|
|
"%ld 0 obj\n"
|
|
"<<\n"
|
|
" /Type /Pages\n"
|
|
" /Kids [ ", kPagesObjectNumber);
|
|
AppendString(buf);
|
|
size_t pages_objsize = strlen(buf);
|
|
for (size_t i = 0; i < pages_.size(); i++) {
|
|
snprintf(buf, sizeof(buf),
|
|
"%ld 0 R ", pages_[i]);
|
|
AppendString(buf);
|
|
pages_objsize += strlen(buf);
|
|
}
|
|
snprintf(buf, sizeof(buf),
|
|
"]\n"
|
|
" /Count %d\n"
|
|
">>\n"
|
|
"endobj\n", pages_.size());
|
|
AppendString(buf);
|
|
pages_objsize += strlen(buf);
|
|
offsets_.back() += pages_objsize; // manipulation #2
|
|
|
|
// INFO
|
|
char* datestr = l_getFormattedDate();
|
|
snprintf(buf, sizeof(buf),
|
|
"%ld 0 obj\n"
|
|
"<<\n"
|
|
" /Producer (Tesseract %s)\n"
|
|
" /CreationDate (D:%s)\n"
|
|
" /Title (%s)"
|
|
">>\n"
|
|
"endobj\n", obj_, VERSION, datestr, title());
|
|
lept_free(datestr);
|
|
AppendPDFObject(buf);
|
|
|
|
snprintf(buf, sizeof(buf),
|
|
"xref\n"
|
|
"0 %ld\n"
|
|
"0000000000 65535 f \n", obj_);
|
|
AppendString(buf);
|
|
for (int i = 1; i < obj_; i++) {
|
|
snprintf(buf, sizeof(buf), "%010ld 00000 n \n", offsets_[i]);
|
|
AppendString(buf);
|
|
}
|
|
snprintf(buf, sizeof(buf),
|
|
"trailer\n"
|
|
"<<\n"
|
|
" /Size %ld\n"
|
|
" /Root %ld 0 R\n"
|
|
" /Info %ld 0 R\n"
|
|
">>\n"
|
|
"startxref\n"
|
|
"%ld\n"
|
|
"%%%%EOF\n",
|
|
obj_,
|
|
1L, // catalog
|
|
obj_ - 1, // info
|
|
offsets_.back());
|
|
|
|
AppendString(buf);
|
|
return true;
|
|
}
|
|
|
|
} // namespace tesseract
|