tesseract::TessdataManager Class Reference

#include <tessdatamanager.h>

Public Member Functions
	TessdataManager ()
	TessdataManager (FileReader reader)
	~TessdataManager ()
bool	swap () const
bool	is_loaded () const
bool	Init (const char *data_file_name)
bool	LoadMemBuffer (const char *name, const char *data, int size)
bool	SaveFile (const STRING &filename, FileWriter writer) const
void	Serialize (GenericVector< char > *data) const
void	Clear ()
void	Directory () const
bool	GetComponent (TessdataType type, TFile *fp)
bool	IsBaseAvailable () const
bool	IsLSTMAvailable () const
const STRING &	GetDataFileName () const
bool	CombineDataFiles (const char *language_data_path_prefix, const char *output_filename)
bool	OverwriteComponents (const char *new_traineddata_filename, char **component_filenames, int num_new_components)
bool	ExtractToFile (const char *filename)

Static Public Member Functions
static bool	TessdataTypeFromFileSuffix (const char *suffix, TessdataType *type)
static bool	TessdataTypeFromFileName (const char *filename, TessdataType *type)

Detailed Description

Definition at line 121 of file tessdatamanager.h.

Constructor & Destructor Documentation

TessdataManager() [1/2]

tesseract::TessdataManager::TessdataManager ( )

inline

Definition at line 123 of file tessdatamanager.h.

: reader_(nullptr), is_loaded_(false), swap_(false) {}

TessdataManager() [2/2]

tesseract::TessdataManager::TessdataManager ( FileReader  reader )

inlineexplicit

Definition at line 124 of file tessdatamanager.h.

      : reader_(reader), is_loaded_(false), swap_(false) {}

~TessdataManager()

tesseract::TessdataManager::~TessdataManager ( )

inline

Definition at line 126 of file tessdatamanager.h.

{}

Member Function Documentation

Clear()

void tesseract::TessdataManager::Clear

(

)

Definition at line 117 of file tessdatamanager.cpp.

                            {
  for (int i = 0; i < TESSDATA_NUM_ENTRIES; ++i) {
    entries_[i].clear();
  }
  is_loaded_ = false;
}

CombineDataFiles()

bool tesseract::TessdataManager::CombineDataFiles	(	const char *	language_data_path_prefix,
		const char *	output_filename
	)

Reads all the standard tesseract config and data files for a language at the given path and bundles them up into one binary data file. Returns true if the combined traineddata file was successfully written.

Definition at line 146 of file tessdatamanager.cpp.

                                 {
  // Load individual tessdata components from files.
  for (int i = 0; i < TESSDATA_NUM_ENTRIES; ++i) {
    TessdataType type;
    ASSERT_HOST(TessdataTypeFromFileSuffix(kTessdataFileSuffixes[i], &type));
    STRING filename = language_data_path_prefix;
    filename += kTessdataFileSuffixes[i];
    FILE *fp = fopen(filename.string(), "rb");
    if (fp != nullptr) {
      fclose(fp);
      if (!LoadDataFromFile(filename, &entries_[type])) {
        tprintf("Load of file %s failed!\n", filename.string());
        return false;
      }
    }
  }
  is_loaded_ = true;

  // Make sure that the required components are present.
  if (!IsBaseAvailable() && !IsLSTMAvailable()) {
    tprintf(
        "Error: traineddata file must contain at least (a unicharset file"
        "and inttemp) OR an lstm file.\n");
    return false;
  }
  // Write updated data to the output traineddata file.
  return SaveFile(output_filename, nullptr);
}

Directory()

void tesseract::TessdataManager::Directory

(

)

const

Definition at line 125 of file tessdatamanager.cpp.

                                      {
  int offset = TESSDATA_NUM_ENTRIES * sizeof(inT64);
  for (int i = 0; i < TESSDATA_NUM_ENTRIES; ++i) {
    if (!entries_[i].empty()) {
      tprintf("%d:%s:size=%d, offset=%d\n", i, kTessdataFileSuffixes[i],
              entries_[i].size(), offset);
      offset += entries_[i].size();
    }
  }
}

ExtractToFile()

bool tesseract::TessdataManager::ExtractToFile

(

const char *

filename

)

Extracts tessdata component implied by the name of the input file from the combined traineddata loaded into TessdataManager. Writes the extracted component to the file indicated by the file name. E.g. if the filename given is somepath/somelang.unicharset, unicharset will be extracted from the data loaded into the TessdataManager and will be written to somepath/somelang.unicharset.

Returns

true if the component was successfully extracted, false if the component was not present in the traineddata loaded into TessdataManager.

Definition at line 196 of file tessdatamanager.cpp.

                                                        {
  TessdataType type = TESSDATA_NUM_ENTRIES;
  ASSERT_HOST(
      tesseract::TessdataManager::TessdataTypeFromFileName(filename, &type));
  if (entries_[type].empty()) return false;
  return SaveDataToFile(entries_[type], filename);
}

GetComponent()

bool tesseract::TessdataManager::GetComponent	(	TessdataType	type,
		TFile *	fp
	)

Definition at line 138 of file tessdatamanager.cpp.

                                                               {
  if (!is_loaded_ && !Init(data_file_name_.string())) return false;
  if (entries_[type].empty()) return false;
  fp->Open(&entries_[type][0], entries_[type].size());
  fp->set_swap(swap_);
  return true;
}

GetDataFileName()

const STRING& tesseract::TessdataManager::GetDataFileName ( ) const

inline

Definition at line 164 of file tessdatamanager.h.

{ return data_file_name_; }

Init()

bool tesseract::TessdataManager::Init

(

const char *

data_file_name

)

Opens and reads the given data file right now.

Returns

true on success.

Definition at line 36 of file tessdatamanager.cpp.

                                                     {
  GenericVector<char> data;
  if (reader_ == nullptr) {
    if (!LoadDataFromFile(data_file_name, &data)) return false;
  } else {
    if (!(*reader_)(data_file_name, &data)) return false;
  }
  return LoadMemBuffer(data_file_name, &data[0], data.size());
}

is_loaded()

bool tesseract::TessdataManager::is_loaded ( ) const

inline

Definition at line 129 of file tessdatamanager.h.

{ return is_loaded_; }

IsBaseAvailable()

bool tesseract::TessdataManager::IsBaseAvailable ( ) const

inline

Definition at line 155 of file tessdatamanager.h.

                               {
    return !entries_[TESSDATA_UNICHARSET].empty() &&
           !entries_[TESSDATA_INTTEMP].empty();
  }

IsLSTMAvailable()

bool tesseract::TessdataManager::IsLSTMAvailable ( ) const

inline

Definition at line 161 of file tessdatamanager.h.

{ return !entries_[TESSDATA_LSTM].empty(); }

LoadMemBuffer()

bool tesseract::TessdataManager::LoadMemBuffer	(	const char *	name,
		const char *	data,
		int	size
	)

Definition at line 47 of file tessdatamanager.cpp.

                                              {
  data_file_name_ = name;
  TFile fp;
  fp.Open(data, size);
  inT32 num_entries = TESSDATA_NUM_ENTRIES;
  if (fp.FRead(&num_entries, sizeof(num_entries), 1) != 1) return false;
  swap_ = num_entries > kMaxNumTessdataEntries || num_entries < 0;
  fp.set_swap(swap_);
  if (swap_) ReverseN(&num_entries, sizeof(num_entries));
  if (num_entries > kMaxNumTessdataEntries || num_entries < 0) return false;
  GenericVector<inT64> offset_table;
  offset_table.resize_no_init(num_entries);
  if (fp.FReadEndian(&offset_table[0], sizeof(offset_table[0]), num_entries) !=
      num_entries)
    return false;
  for (int i = 0; i < num_entries && i < TESSDATA_NUM_ENTRIES; ++i) {
    if (offset_table[i] >= 0) {
      inT64 entry_size = size - offset_table[i];
      int j = i + 1;
      while (j < num_entries && offset_table[j] == -1) ++j;
      if (j < num_entries) entry_size = offset_table[j] - offset_table[i];
      entries_[i].resize_no_init(entry_size);
      if (fp.FRead(&entries_[i][0], 1, entry_size) != entry_size) return false;
    }
  }
  is_loaded_ = true;
  return true;
}

OverwriteComponents()

bool tesseract::TessdataManager::OverwriteComponents	(	const char *	new_traineddata_filename,
		char **	component_filenames,
		int	num_new_components
	)

Gets the individual components from the data_file_ with which the class was initialized. Overwrites the components specified by component_filenames. Writes the updated traineddata file to new_traineddata_filename.

Definition at line 177 of file tessdatamanager.cpp.

                            {
  // Open the files with the new components.
  for (int i = 0; i < num_new_components; ++i) {
    TessdataType type;
    if (TessdataTypeFromFileName(component_filenames[i], &type)) {
      if (!LoadDataFromFile(component_filenames[i], &entries_[type])) {
        tprintf("Failed to read component file:%s\n", component_filenames[i]);
        return false;
      }
    }
  }

  // Write updated data to the output traineddata file.
  return SaveFile(new_traineddata_filename, nullptr);
}

SaveFile()

bool tesseract::TessdataManager::SaveFile	(	const STRING &	filename,
		FileWriter	writer
	)		const

Definition at line 78 of file tessdatamanager.cpp.

                                                        {
  ASSERT_HOST(is_loaded_);
  GenericVector<char> data;
  Serialize(&data);
  if (writer == nullptr)
    return SaveDataToFile(data, filename);
  else
    return (*writer)(data, filename);
}

Serialize()

void tesseract::TessdataManager::Serialize

(

GenericVector< char > *

data

)

const

Definition at line 90 of file tessdatamanager.cpp.

                                                               {
  ASSERT_HOST(is_loaded_);
  // Compute the offset_table and total size.
  inT64 offset_table[TESSDATA_NUM_ENTRIES];
  inT64 offset = sizeof(inT32) + sizeof(offset_table);
  for (int i = 0; i < TESSDATA_NUM_ENTRIES; ++i) {
    if (entries_[i].empty()) {
      offset_table[i] = -1;
    } else {
      offset_table[i] = offset;
      offset += entries_[i].size();
    }
  }
  data->init_to_size(offset, 0);
  inT32 num_entries = TESSDATA_NUM_ENTRIES;
  TFile fp;
  fp.OpenWrite(data);
  fp.FWrite(&num_entries, sizeof(num_entries), 1);
  fp.FWrite(offset_table, sizeof(offset_table), 1);
  for (int i = 0; i < TESSDATA_NUM_ENTRIES; ++i) {
    if (!entries_[i].empty()) {
      fp.FWrite(&entries_[i][0], entries_[i].size(), 1);
    }
  }
}

swap()

bool tesseract::TessdataManager::swap ( ) const

inline

Definition at line 128 of file tessdatamanager.h.

{ return swap_; }

TessdataTypeFromFileName()

bool tesseract::TessdataManager::TessdataTypeFromFileName ( const char *  filename, TessdataType *  type  )

static

Tries to determine tessdata component file suffix from filename, returns true on success.

Definition at line 217 of file tessdatamanager.cpp.

                                                                   {
  // Get the file suffix (extension)
  const char *suffix = strrchr(filename, '.');
  if (suffix == nullptr || *(++suffix) == '\0') return false;
  return TessdataTypeFromFileSuffix(suffix, type);
}

TessdataTypeFromFileSuffix()

bool tesseract::TessdataManager::TessdataTypeFromFileSuffix ( const char *  suffix, TessdataType *  type  )

static

Fills type with TessdataType of the tessdata component represented by the given file name. E.g. tessdata/eng.unicharset -> TESSDATA_UNICHARSET.

Returns

true if the tessdata component type could be determined from the given file name.

Definition at line 204 of file tessdatamanager.cpp.

                                                                     {
  for (int i = 0; i < TESSDATA_NUM_ENTRIES; ++i) {
    if (strcmp(kTessdataFileSuffixes[i], suffix) == 0) {
      *type = static_cast<TessdataType>(i);
      return true;
    }
  }
  tprintf("TessdataManager can't determine which tessdata"
         " component is represented by %s\n", suffix);
  return false;
}

---

The documentation for this class was generated from the following files:

• /home/stefan/src/github/tesseract-ocr/tesseract/ccutil/tessdatamanager.h
• /home/stefan/src/github/tesseract-ocr/tesseract/ccutil/tessdatamanager.cpp