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331cc84d8d
tesseract/src/api/baseapi.cpp
Stefan Weil 331cc84d8d Remove assertions for unsupported locale settings 
The latest code passed all unittests with locale de_DE.UTF-8
and has fixed the locale issues which were reported on GitHub.
Therefore the assertions can be removed.

Any remaining locale issue will be fixed when it is identified.
To help finding such remaining isses, debug code now uses the
user's locale settings instead of the default "C" locale for all
executables which use TessBaseAPI.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
2019-05-16 13:59:39 +02:00

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/**********************************************************************
* File: baseapi.cpp
* Description: Simple API for calling tesseract.
* Author: Ray Smith
*
* (C) Copyright 2006, Google Inc.
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
** http://www.apache.org/licenses/LICENSE-2.0
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*
**********************************************************************/
// Include automatically generated configuration file if running autoconf.
#ifdef HAVE_CONFIG_H
#include "config_auto.h"
#endif
#include "baseapi.h"
#ifdef __linux__
#include <csignal> // for sigaction, SA_RESETHAND, SIGBUS, SIGFPE
#endif
#if defined(_WIN32)
#if defined(__MINGW32__)
// workaround for stdlib.h with -std=c++11 for _splitpath and _MAX_FNAME
#undef __STRICT_ANSI__
#endif // __MINGW32__
#include <fcntl.h>
#include <io.h>
#else
#include <dirent.h> // for closedir, opendir, readdir, DIR, dirent
#include <libgen.h>
#include <sys/types.h>
#include <sys/stat.h> // for stat, S_IFDIR
#include <unistd.h>
#endif // _WIN32
#include <cmath> // for round, M_PI
#include <cstdint> // for int32_t
#include <cstring> // for strcmp, strcpy
#include <fstream> // for size_t
#include <iostream> // for std::cin
#include <locale> // for std::locale::classic
#include <memory> // for std::unique_ptr
#include <set> // for std::pair
#include <sstream> // for std::stringstream
#include <vector> // for std::vector
#include "allheaders.h" // for pixDestroy, boxCreate, boxaAddBox, box...
#include "blobclass.h" // for ExtractFontName
#include "boxword.h" // for BoxWord
#include "config_auto.h" // for PACKAGE_VERSION
#include "coutln.h" // for C_OUTLINE_IT, C_OUTLINE_LIST
#include "dawg_cache.h" // for DawgCache
#include "dict.h" // for Dict
#include "edgblob.h" // for extract_edges
#include "elst.h" // for ELIST_ITERATOR, ELISTIZE, ELISTIZEH
#include "environ.h" // for l_uint8
#include "equationdetect.h" // for EquationDetect
#include "errcode.h" // for ASSERT_HOST
#include "globaloc.h" // for SavePixForCrash, signal_exit
#include "helpers.h" // for IntCastRounded, chomp_string
#include "imageio.h" // for IFF_TIFF_G4, IFF_TIFF, IFF_TIFF_G3
#ifndef DISABLED_LEGACY_ENGINE
#include "intfx.h" // for INT_FX_RESULT_STRUCT
#endif
#include "mutableiterator.h" // for MutableIterator
#include "normalis.h" // for kBlnBaselineOffset, kBlnXHeight
#include "ocrclass.h" // for ETEXT_DESC
#if defined(USE_OPENCL)
#include "openclwrapper.h" // for OpenclDevice
#endif
#include "osdetect.h" // for OSResults, OSBestResult, OrientationId...
#include "pageres.h" // for PAGE_RES_IT, WERD_RES, PAGE_RES, CR_DE...
#include "paragraphs.h" // for DetectParagraphs
#include "params.h" // for BoolParam, IntParam, DoubleParam, Stri...
#include "pdblock.h" // for PDBLK
#include "points.h" // for FCOORD
#include "polyblk.h" // for POLY_BLOCK
#include "rect.h" // for TBOX
#include "renderer.h" // for TessResultRenderer
#include "resultiterator.h" // for ResultIterator
#include "stepblob.h" // for C_BLOB_IT, C_BLOB, C_BLOB_LIST
#include "strngs.h" // for STRING
#include "tessdatamanager.h" // for TessdataManager, kTrainedDataSuffix
#include "tesseractclass.h" // for Tesseract
#include "thresholder.h" // for ImageThresholder
#include "tprintf.h" // for tprintf
#include "werd.h" // for WERD, WERD_IT, W_FUZZY_NON, W_FUZZY_SP
BOOL_VAR(stream_filelist, false, "Stream a filelist from stdin");
namespace tesseract {
/** Minimum sensible image size to be worth running tesseract. */
const int kMinRectSize = 10;
/** Character returned when Tesseract couldn't recognize as anything. */
const char kTesseractReject = '~';
/** Character used by UNLV error counter as a reject. */
const char kUNLVReject = '~';
/** Character used by UNLV as a suspect marker. */
const char kUNLVSuspect = '^';
/**
* Filename used for input image file, from which to derive a name to search
* for a possible UNLV zone file, if none is specified by SetInputName.
*/
const char* kInputFile = "noname.tif";
/**
* Temp file used for storing current parameters before applying retry values.
*/
const char* kOldVarsFile = "failed_vars.txt";
/** Max string length of an int. */
const int kMaxIntSize = 22;
/* Add all available languages recursively.
*/
static void addAvailableLanguages(const STRING &datadir, const STRING &base,
GenericVector<STRING>* langs)
{
const STRING base2 = (base.string()[0] == '\0') ? base : base + "/";
const size_t extlen = sizeof(kTrainedDataSuffix);
#ifdef _WIN32
WIN32_FIND_DATA data;
HANDLE handle = FindFirstFile((datadir + base2 + "*").string(), &data);
if (handle != INVALID_HANDLE_VALUE) {
BOOL result = TRUE;
for (; result;) {
char *name = data.cFileName;
// Skip '.', '..', and hidden files
if (name[0] != '.') {
if ((data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) ==
FILE_ATTRIBUTE_DIRECTORY) {
addAvailableLanguages(datadir, base2 + name, langs);
} else {
size_t len = strlen(name);
if (len > extlen && name[len - extlen] == '.' &&
strcmp(&name[len - extlen + 1], kTrainedDataSuffix) == 0) {
name[len - extlen] = '\0';
langs->push_back(base2 + name);
}
}
}
result = FindNextFile(handle, &data);
}
FindClose(handle);
}
#else // _WIN32
DIR* dir = opendir((datadir + base).string());
if (dir != nullptr) {
dirent *de;
while ((de = readdir(dir))) {
char *name = de->d_name;
// Skip '.', '..', and hidden files
if (name[0] != '.') {
struct stat st;
if (stat((datadir + base2 + name).string(), &st) == 0 &&
(st.st_mode & S_IFDIR) == S_IFDIR) {
addAvailableLanguages(datadir, base2 + name, langs);
} else {
size_t len = strlen(name);
if (len > extlen && name[len - extlen] == '.' &&
strcmp(&name[len - extlen + 1], kTrainedDataSuffix) == 0) {
name[len - extlen] = '\0';
langs->push_back(base2 + name);
}
}
}
}
closedir(dir);
}
#endif
}
// Compare two STRING values (used for sorting).
static int CompareSTRING(const void* p1, const void* p2) {
const auto* s1 = static_cast<const STRING*>(p1);
const auto* s2 = static_cast<const STRING*>(p2);
return strcmp(s1->c_str(), s2->c_str());
}
TessBaseAPI::TessBaseAPI()
: tesseract_(nullptr),
osd_tesseract_(nullptr),
equ_detect_(nullptr),
reader_(nullptr),
// Thresholder is initialized to nullptr here, but will be set before use by:
// A constructor of a derived API, SetThresholder(), or
// created implicitly when used in InternalSetImage.
thresholder_(nullptr),
paragraph_models_(nullptr),
block_list_(nullptr),
page_res_(nullptr),
input_file_(nullptr),
output_file_(nullptr),
datapath_(nullptr),
language_(nullptr),
last_oem_requested_(OEM_DEFAULT),
recognition_done_(false),
truth_cb_(nullptr),
rect_left_(0),
rect_top_(0),
rect_width_(0),
rect_height_(0),
image_width_(0),
image_height_(0) {
#if defined(DEBUG)
// The Tesseract executables would use the "C" locale by default,
// but other software which is linked against the Tesseract library
// typically uses the locale from the user's environment.
// Here the default is overridden to allow debugging of potential
// problems caused by the locale settings.
// Use the current locale if building debug code.
std::locale::global(std::locale(""));
#endif
}
TessBaseAPI::~TessBaseAPI() {
End();
}
/**
* Returns the version identifier as a static string. Do not delete.
*/
const char* TessBaseAPI::Version() {
return PACKAGE_VERSION;
}
/**
* If compiled with OpenCL AND an available OpenCL
* device is deemed faster than serial code, then
* "device" is populated with the cl_device_id
* and returns sizeof(cl_device_id)
* otherwise *device=nullptr and returns 0.
*/
size_t TessBaseAPI::getOpenCLDevice(void **data) {
#ifdef USE_OPENCL
ds_device device = OpenclDevice::getDeviceSelection();
if (device.type == DS_DEVICE_OPENCL_DEVICE) {
*data = new cl_device_id;
memcpy(*data, &device.oclDeviceID, sizeof(cl_device_id));
return sizeof(cl_device_id);
}
#endif
*data = nullptr;
return 0;
}
/**
* Writes the thresholded image to stderr as a PBM file on receipt of a
* SIGSEGV, SIGFPE, or SIGBUS signal. (Linux/Unix only).
*/
void TessBaseAPI::CatchSignals() {
#ifdef __linux__
struct sigaction action;
memset(&action, 0, sizeof(action));
action.sa_handler = &signal_exit;
action.sa_flags = SA_RESETHAND;
sigaction(SIGSEGV, &action, nullptr);
sigaction(SIGFPE, &action, nullptr);
sigaction(SIGBUS, &action, nullptr);
#else
// Warn API users that an implementation is needed.
tprintf("CatchSignals has no non-linux implementation!\n");
#endif
}
/**
* Set the name of the input file. Needed only for training and
* loading a UNLV zone file.
*/
void TessBaseAPI::SetInputName(const char* name) {
if (input_file_ == nullptr)
input_file_ = new STRING(name);
else
*input_file_ = name;
}
/** Set the name of the output files. Needed only for debugging. */
void TessBaseAPI::SetOutputName(const char* name) {
if (output_file_ == nullptr)
output_file_ = new STRING(name);
else
*output_file_ = name;
}
bool TessBaseAPI::SetVariable(const char* name, const char* value) {
if (tesseract_ == nullptr) tesseract_ = new Tesseract;
return ParamUtils::SetParam(name, value, SET_PARAM_CONSTRAINT_NON_INIT_ONLY,
tesseract_->params());
}
bool TessBaseAPI::SetDebugVariable(const char* name, const char* value) {
if (tesseract_ == nullptr) tesseract_ = new Tesseract;
return ParamUtils::SetParam(name, value, SET_PARAM_CONSTRAINT_DEBUG_ONLY,
tesseract_->params());
}
bool TessBaseAPI::GetIntVariable(const char *name, int *value) const {
auto *p = ParamUtils::FindParam<IntParam>(
name, GlobalParams()->int_params, tesseract_->params()->int_params);
if (p == nullptr) return false;
*value = (int32_t)(*p);
return true;
}
bool TessBaseAPI::GetBoolVariable(const char *name, bool *value) const {
auto *p = ParamUtils::FindParam<BoolParam>(
name, GlobalParams()->bool_params, tesseract_->params()->bool_params);
if (p == nullptr) return false;
*value = bool(*p);
return true;
}
const char *TessBaseAPI::GetStringVariable(const char *name) const {
auto *p = ParamUtils::FindParam<StringParam>(
name, GlobalParams()->string_params, tesseract_->params()->string_params);
return (p != nullptr) ? p->string() : nullptr;
}
bool TessBaseAPI::GetDoubleVariable(const char *name, double *value) const {
auto *p = ParamUtils::FindParam<DoubleParam>(
name, GlobalParams()->double_params, tesseract_->params()->double_params);
if (p == nullptr) return false;
*value = (double)(*p);
return true;
}
/** Get value of named variable as a string, if it exists. */
bool TessBaseAPI::GetVariableAsString(const char *name, STRING *val) {
return ParamUtils::GetParamAsString(name, tesseract_->params(), val);
}
/** Print Tesseract parameters to the given file. */
void TessBaseAPI::PrintVariables(FILE *fp) const {
ParamUtils::PrintParams(fp, tesseract_->params());
}
/**
* The datapath must be the name of the data directory or
* some other file in which the data directory resides (for instance argv[0].)
* The language is (usually) an ISO 639-3 string or nullptr will default to eng.
* If numeric_mode is true, then only digits and Roman numerals will
* be returned.
* @return: 0 on success and -1 on initialization failure.
*/
int TessBaseAPI::Init(const char* datapath, const char* language,
OcrEngineMode oem, char **configs, int configs_size,
const GenericVector<STRING> *vars_vec,
const GenericVector<STRING> *vars_values,
bool set_only_non_debug_params) {
return Init(datapath, 0, language, oem, configs, configs_size, vars_vec,
vars_values, set_only_non_debug_params, nullptr);
}
// In-memory version reads the traineddata file directly from the given
// data[data_size] array. Also implements the version with a datapath in data,
// flagged by data_size = 0.
int TessBaseAPI::Init(const char* data, int data_size, const char* language,
OcrEngineMode oem, char** configs, int configs_size,
const GenericVector<STRING>* vars_vec,
const GenericVector<STRING>* vars_values,
bool set_only_non_debug_params, FileReader reader) {
// Default language is "eng".
if (language == nullptr) language = "eng";
STRING datapath = data_size == 0 ? data : language;
// If the datapath, OcrEngineMode or the language have changed - start again.
// Note that the language_ field stores the last requested language that was
// initialized successfully, while tesseract_->lang stores the language
// actually used. They differ only if the requested language was nullptr, in
// which case tesseract_->lang is set to the Tesseract default ("eng").
if (tesseract_ != nullptr &&
(datapath_ == nullptr || language_ == nullptr || *datapath_ != datapath ||
last_oem_requested_ != oem ||
(*language_ != language && tesseract_->lang != language))) {
delete tesseract_;
tesseract_ = nullptr;
}
#ifdef USE_OPENCL
OpenclDevice od;
od.InitEnv();
#endif
bool reset_classifier = true;
if (tesseract_ == nullptr) {
reset_classifier = false;
tesseract_ = new Tesseract;
if (reader != nullptr) reader_ = reader;
TessdataManager mgr(reader_);
if (data_size != 0) {
mgr.LoadMemBuffer(language, data, data_size);
}
if (tesseract_->init_tesseract(
datapath.string(),
output_file_ != nullptr ? output_file_->string() : nullptr,
language, oem, configs, configs_size, vars_vec, vars_values,
set_only_non_debug_params, &mgr) != 0) {
return -1;
}
}
// Update datapath and language requested for the last valid initialization.
if (datapath_ == nullptr)
datapath_ = new STRING(datapath);
else
*datapath_ = datapath;
if ((strcmp(datapath_->string(), "") == 0) &&
(strcmp(tesseract_->datadir.string(), "") != 0))
*datapath_ = tesseract_->datadir;
if (language_ == nullptr)
language_ = new STRING(language);
else
*language_ = language;
last_oem_requested_ = oem;
#ifndef DISABLED_LEGACY_ENGINE
// For same language and datapath, just reset the adaptive classifier.
if (reset_classifier) {
tesseract_->ResetAdaptiveClassifier();
}
#endif // ndef DISABLED_LEGACY_ENGINE
return 0;
}
/**
* Returns the languages string used in the last valid initialization.
* If the last initialization specified "deu+hin" then that will be
* returned. If hin loaded eng automatically as well, then that will
* not be included in this list. To find the languages actually
* loaded use GetLoadedLanguagesAsVector.
* The returned string should NOT be deleted.
*/
const char* TessBaseAPI::GetInitLanguagesAsString() const {
return (language_ == nullptr || language_->string() == nullptr) ?
"" : language_->string();
}
/**
* Returns the loaded languages in the vector of STRINGs.
* Includes all languages loaded by the last Init, including those loaded
* as dependencies of other loaded languages.
*/
void TessBaseAPI::GetLoadedLanguagesAsVector(
GenericVector<STRING>* langs) const {
langs->clear();
if (tesseract_ != nullptr) {
langs->push_back(tesseract_->lang);
int num_subs = tesseract_->num_sub_langs();
for (int i = 0; i < num_subs; ++i)
langs->push_back(tesseract_->get_sub_lang(i)->lang);
}
}
/**
* Returns the available languages in the sorted vector of STRINGs.
*/
void TessBaseAPI::GetAvailableLanguagesAsVector(
GenericVector<STRING>* langs) const {
langs->clear();
if (tesseract_ != nullptr) {
addAvailableLanguages(tesseract_->datadir, "", langs);
langs->sort(CompareSTRING);
}
}
//TODO(amit): Adapt to lstm
#ifndef DISABLED_LEGACY_ENGINE
/**
* Init only the lang model component of Tesseract. The only functions
* that work after this init are SetVariable and IsValidWord.
* WARNING: temporary! This function will be removed from here and placed
* in a separate API at some future time.
*/
int TessBaseAPI::InitLangMod(const char* datapath, const char* language) {
if (tesseract_ == nullptr)
tesseract_ = new Tesseract;
else
ParamUtils::ResetToDefaults(tesseract_->params());
TessdataManager mgr;
return tesseract_->init_tesseract_lm(datapath, nullptr, language, &mgr);
}
#endif // ndef DISABLED_LEGACY_ENGINE
/**
* Init only for page layout analysis. Use only for calls to SetImage and
* AnalysePage. Calls that attempt recognition will generate an error.
*/
void TessBaseAPI::InitForAnalysePage() {
if (tesseract_ == nullptr) {
tesseract_ = new Tesseract;
#ifndef DISABLED_LEGACY_ENGINE
tesseract_->InitAdaptiveClassifier(nullptr);
#endif
}
}
/**
* Read a "config" file containing a set of parameter name, value pairs.
* Searches the standard places: tessdata/configs, tessdata/tessconfigs
* and also accepts a relative or absolute path name.
*/
void TessBaseAPI::ReadConfigFile(const char* filename) {
tesseract_->read_config_file(filename, SET_PARAM_CONSTRAINT_NON_INIT_ONLY);
}
/** Same as above, but only set debug params from the given config file. */
void TessBaseAPI::ReadDebugConfigFile(const char* filename) {
tesseract_->read_config_file(filename, SET_PARAM_CONSTRAINT_DEBUG_ONLY);
}
/**
* Set the current page segmentation mode. Defaults to PSM_AUTO.
* The mode is stored as an IntParam so it can also be modified by
* ReadConfigFile or SetVariable("tessedit_pageseg_mode", mode as string).
*/
void TessBaseAPI::SetPageSegMode(PageSegMode mode) {
if (tesseract_ == nullptr)
tesseract_ = new Tesseract;
tesseract_->tessedit_pageseg_mode.set_value(mode);
}
/** Return the current page segmentation mode. */
PageSegMode TessBaseAPI::GetPageSegMode() const {
if (tesseract_ == nullptr)
return PSM_SINGLE_BLOCK;
return static_cast<PageSegMode>(
static_cast<int>(tesseract_->tessedit_pageseg_mode));
}
/**
* Recognize a rectangle from an image and return the result as a string.
* May be called many times for a single Init.
* Currently has no error checking.
* Greyscale of 8 and color of 24 or 32 bits per pixel may be given.
* Palette color images will not work properly and must be converted to
* 24 bit.
* Binary images of 1 bit per pixel may also be given but they must be
* byte packed with the MSB of the first byte being the first pixel, and a
* one pixel is WHITE. For binary images set bytes_per_pixel=0.
* The recognized text is returned as a char* which is coded
* as UTF8 and must be freed with the delete [] operator.
*/
char* TessBaseAPI::TesseractRect(const unsigned char* imagedata,
int bytes_per_pixel,
int bytes_per_line,
int left, int top,
int width, int height) {
if (tesseract_ == nullptr || width < kMinRectSize || height < kMinRectSize)
return nullptr; // Nothing worth doing.
// Since this original api didn't give the exact size of the image,
// we have to invent a reasonable value.
int bits_per_pixel = bytes_per_pixel == 0 ? 1 : bytes_per_pixel * 8;
SetImage(imagedata, bytes_per_line * 8 / bits_per_pixel, height + top,
bytes_per_pixel, bytes_per_line);
SetRectangle(left, top, width, height);
return GetUTF8Text();
}
#ifndef DISABLED_LEGACY_ENGINE
/**
* Call between pages or documents etc to free up memory and forget
* adaptive data.
*/
void TessBaseAPI::ClearAdaptiveClassifier() {
if (tesseract_ == nullptr)
return;
tesseract_->ResetAdaptiveClassifier();
tesseract_->ResetDocumentDictionary();
}
#endif // ndef DISABLED_LEGACY_ENGINE
/**
* Provide an image for Tesseract to recognize. Format is as
* TesseractRect above. Copies the image buffer and converts to Pix.
* SetImage clears all recognition results, and sets the rectangle to the
* full image, so it may be followed immediately by a GetUTF8Text, and it
* will automatically perform recognition.
*/
void TessBaseAPI::SetImage(const unsigned char* imagedata,
int width, int height,
int bytes_per_pixel, int bytes_per_line) {
if (InternalSetImage()) {
thresholder_->SetImage(imagedata, width, height,
bytes_per_pixel, bytes_per_line);
SetInputImage(thresholder_->GetPixRect());
}
}
void TessBaseAPI::SetSourceResolution(int ppi) {
if (thresholder_)
thresholder_->SetSourceYResolution(ppi);
else
tprintf("Please call SetImage before SetSourceResolution.\n");
}
/**
* Provide an image for Tesseract to recognize. As with SetImage above,
* Tesseract takes its own copy of the image, so it need not persist until
* after Recognize.
* Pix vs raw, which to use?
* Use Pix where possible. Tesseract uses Pix as its internal representation
* and it is therefore more efficient to provide a Pix directly.
*/
void TessBaseAPI::SetImage(Pix* pix) {
if (InternalSetImage()) {
if (pixGetSpp(pix) == 4 && pixGetInputFormat(pix) == IFF_PNG) {
// remove alpha channel from png
Pix* p1 = pixRemoveAlpha(pix);
pixSetSpp(p1, 3);
(void)pixCopy(pix, p1);
pixDestroy(&p1);
}
thresholder_->SetImage(pix);
SetInputImage(thresholder_->GetPixRect());
}
}
/**
* Restrict recognition to a sub-rectangle of the image. Call after SetImage.
* Each SetRectangle clears the recogntion results so multiple rectangles
* can be recognized with the same image.
*/
void TessBaseAPI::SetRectangle(int left, int top, int width, int height) {
if (thresholder_ == nullptr)
return;
thresholder_->SetRectangle(left, top, width, height);
ClearResults();
}
/**
* ONLY available after SetImage if you have Leptonica installed.
* Get a copy of the internal thresholded image from Tesseract.
*/
Pix* TessBaseAPI::GetThresholdedImage() {
if (tesseract_ == nullptr || thresholder_ == nullptr) return nullptr;
if (tesseract_->pix_binary() == nullptr &&
!Threshold(tesseract_->mutable_pix_binary())) {
return nullptr;
}
return pixClone(tesseract_->pix_binary());
}
/**
* Get the result of page layout analysis as a leptonica-style
* Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
*/
Boxa* TessBaseAPI::GetRegions(Pixa** pixa) {
return GetComponentImages(RIL_BLOCK, false, pixa, nullptr);
}
/**
* Get the textlines as a leptonica-style Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
* If blockids is not nullptr, the block-id of each line is also returned as an
* array of one element per line. delete [] after use.
* If paraids is not nullptr, the paragraph-id of each line within its block is
* also returned as an array of one element per line. delete [] after use.
*/
Boxa* TessBaseAPI::GetTextlines(const bool raw_image, const int raw_padding,
Pixa** pixa, int** blockids, int** paraids) {
return GetComponentImages(RIL_TEXTLINE, true, raw_image, raw_padding,
pixa, blockids, paraids);
}
/**
* Get textlines and strips of image regions as a leptonica-style Boxa, Pixa
* pair, in reading order. Enables downstream handling of non-rectangular
* regions.
* Can be called before or after Recognize.
* If blockids is not nullptr, the block-id of each line is also returned as an
* array of one element per line. delete [] after use.
*/
Boxa* TessBaseAPI::GetStrips(Pixa** pixa, int** blockids) {
return GetComponentImages(RIL_TEXTLINE, false, pixa, blockids);
}
/**
* Get the words as a leptonica-style
* Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
*/
Boxa* TessBaseAPI::GetWords(Pixa** pixa) {
return GetComponentImages(RIL_WORD, true, pixa, nullptr);
}
/**
* Gets the individual connected (text) components (created
* after pages segmentation step, but before recognition)
* as a leptonica-style Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
*/
Boxa* TessBaseAPI::GetConnectedComponents(Pixa** pixa) {
return GetComponentImages(RIL_SYMBOL, true, pixa, nullptr);
}
/**
* Get the given level kind of components (block, textline, word etc.) as a
* leptonica-style Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
* If blockids is not nullptr, the block-id of each component is also returned
* as an array of one element per component. delete [] after use.
* If text_only is true, then only text components are returned.
*/
Boxa* TessBaseAPI::GetComponentImages(PageIteratorLevel level,
bool text_only, bool raw_image,
const int raw_padding,
Pixa** pixa, int** blockids,
int** paraids) {
PageIterator* page_it = GetIterator();
if (page_it == nullptr)
page_it = AnalyseLayout();
if (page_it == nullptr)
return nullptr; // Failed.
// Count the components to get a size for the arrays.
int component_count = 0;
int left, top, right, bottom;
TessResultCallback<bool>* get_bbox = nullptr;
if (raw_image) {
// Get bounding box in original raw image with padding.
get_bbox = NewPermanentTessCallback(page_it, &PageIterator::BoundingBox,
level, raw_padding,
&left, &top, &right, &bottom);
} else {
// Get bounding box from binarized imaged. Note that this could be
// differently scaled from the original image.
get_bbox = NewPermanentTessCallback(page_it,
&PageIterator::BoundingBoxInternal,
level, &left, &top, &right, &bottom);
}
do {
if (get_bbox->Run() &&
(!text_only || PTIsTextType(page_it->BlockType())))
++component_count;
} while (page_it->Next(level));
Boxa* boxa = boxaCreate(component_count);
if (pixa != nullptr)
*pixa = pixaCreate(component_count);
if (blockids != nullptr)
*blockids = new int[component_count];
if (paraids != nullptr)
*paraids = new int[component_count];
int blockid = 0;
int paraid = 0;
int component_index = 0;
page_it->Begin();
do {
if (get_bbox->Run() &&
(!text_only || PTIsTextType(page_it->BlockType()))) {
Box* lbox = boxCreate(left, top, right - left, bottom - top);
boxaAddBox(boxa, lbox, L_INSERT);
if (pixa != nullptr) {
Pix* pix = nullptr;
if (raw_image) {
pix = page_it->GetImage(level, raw_padding, GetInputImage(), &left,
&top);
} else {
pix = page_it->GetBinaryImage(level);
}
pixaAddPix(*pixa, pix, L_INSERT);
pixaAddBox(*pixa, lbox, L_CLONE);
}
if (paraids != nullptr) {
(*paraids)[component_index] = paraid;
if (page_it->IsAtFinalElement(RIL_PARA, level))
++paraid;
}
if (blockids != nullptr) {
(*blockids)[component_index] = blockid;
if (page_it->IsAtFinalElement(RIL_BLOCK, level)) {
++blockid;
paraid = 0;
}
}
++component_index;
}
} while (page_it->Next(level));
delete page_it;
delete get_bbox;
return boxa;
}
int TessBaseAPI::GetThresholdedImageScaleFactor() const {
if (thresholder_ == nullptr) {
return 0;
}
return thresholder_->GetScaleFactor();
}
/**
* Runs page layout analysis in the mode set by SetPageSegMode.
* May optionally be called prior to Recognize to get access to just
* the page layout results. Returns an iterator to the results.
* If merge_similar_words is true, words are combined where suitable for use
* with a line recognizer. Use if you want to use AnalyseLayout to find the
* textlines, and then want to process textline fragments with an external
* line recognizer.
* Returns nullptr on error or an empty page.
* The returned iterator must be deleted after use.
* WARNING! This class points to data held within the TessBaseAPI class, and
* therefore can only be used while the TessBaseAPI class still exists and
* has not been subjected to a call of Init, SetImage, Recognize, Clear, End
* DetectOS, or anything else that changes the internal PAGE_RES.
*/
PageIterator* TessBaseAPI::AnalyseLayout() { return AnalyseLayout(false); }
PageIterator* TessBaseAPI::AnalyseLayout(bool merge_similar_words) {
if (FindLines() == 0) {
if (block_list_->empty())
return nullptr; // The page was empty.
page_res_ = new PAGE_RES(merge_similar_words, block_list_, nullptr);
DetectParagraphs(false);
return new PageIterator(
page_res_, tesseract_, thresholder_->GetScaleFactor(),
thresholder_->GetScaledYResolution(),
rect_left_, rect_top_, rect_width_, rect_height_);
}
return nullptr;
}
/**
* Recognize the tesseract global image and return the result as Tesseract
* internal structures.
*/
int TessBaseAPI::Recognize(ETEXT_DESC* monitor) {
if (tesseract_ == nullptr)
return -1;
if (FindLines() != 0)
return -1;
delete page_res_;
if (block_list_->empty()) {
page_res_ = new PAGE_RES(false, block_list_,
&tesseract_->prev_word_best_choice_);
return 0; // Empty page.
}
tesseract_->SetBlackAndWhitelist();
recognition_done_ = true;
#ifndef DISABLED_LEGACY_ENGINE
if (tesseract_->tessedit_resegment_from_line_boxes) {
page_res_ = tesseract_->ApplyBoxes(*input_file_, true, block_list_);
} else if (tesseract_->tessedit_resegment_from_boxes) {
page_res_ = tesseract_->ApplyBoxes(*input_file_, false, block_list_);
} else
#endif // ndef DISABLED_LEGACY_ENGINE
{
page_res_ = new PAGE_RES(tesseract_->AnyLSTMLang(),
block_list_, &tesseract_->prev_word_best_choice_);
}
if (page_res_ == nullptr) {
return -1;
}
if (tesseract_->tessedit_train_line_recognizer) {
tesseract_->TrainLineRecognizer(*input_file_, *output_file_, block_list_);
tesseract_->CorrectClassifyWords(page_res_);
return 0;
}
#ifndef DISABLED_LEGACY_ENGINE
if (tesseract_->tessedit_make_boxes_from_boxes) {
tesseract_->CorrectClassifyWords(page_res_);
return 0;
}
#endif // ndef DISABLED_LEGACY_ENGINE
if (truth_cb_ != nullptr) {
tesseract_->wordrec_run_blamer.set_value(true);
auto *page_it = new PageIterator(
page_res_, tesseract_, thresholder_->GetScaleFactor(),
thresholder_->GetScaledYResolution(),
rect_left_, rect_top_, rect_width_, rect_height_);
truth_cb_->Run(tesseract_->getDict().getUnicharset(),
image_height_, page_it, this->tesseract()->pix_grey());
delete page_it;
}
int result = 0;
if (tesseract_->interactive_display_mode) {
#ifndef GRAPHICS_DISABLED
tesseract_->pgeditor_main(rect_width_, rect_height_, page_res_);
#endif // GRAPHICS_DISABLED
// The page_res is invalid after an interactive session, so cleanup
// in a way that lets us continue to the next page without crashing.
delete page_res_;
page_res_ = nullptr;
return -1;
#ifndef DISABLED_LEGACY_ENGINE
} else if (tesseract_->tessedit_train_from_boxes) {
STRING fontname;
ExtractFontName(*output_file_, &fontname);
tesseract_->ApplyBoxTraining(fontname, page_res_);
} else if (tesseract_->tessedit_ambigs_training) {
FILE *training_output_file = tesseract_->init_recog_training(*input_file_);
// OCR the page segmented into words by tesseract.
tesseract_->recog_training_segmented(
*input_file_, page_res_, monitor, training_output_file);
fclose(training_output_file);
#endif // ndef DISABLED_LEGACY_ENGINE
} else {
// Now run the main recognition.
bool wait_for_text = true;
GetBoolVariable("paragraph_text_based", &wait_for_text);
if (!wait_for_text) DetectParagraphs(false);
if (tesseract_->recog_all_words(page_res_, monitor, nullptr, nullptr, 0)) {
if (wait_for_text) DetectParagraphs(true);
} else {
result = -1;
}
}
return result;
}
#ifndef DISABLED_LEGACY_ENGINE
/** Tests the chopper by exhaustively running chop_one_blob. */
int TessBaseAPI::RecognizeForChopTest(ETEXT_DESC* monitor) {
if (tesseract_ == nullptr)
return -1;
if (thresholder_ == nullptr || thresholder_->IsEmpty()) {
tprintf("Please call SetImage before attempting recognition.\n");
return -1;
}
if (page_res_ != nullptr)
ClearResults();
if (FindLines() != 0)
return -1;
// Additional conditions under which chopper test cannot be run
if (tesseract_->interactive_display_mode) return -1;
recognition_done_ = true;
page_res_ = new PAGE_RES(false, block_list_,
&(tesseract_->prev_word_best_choice_));
PAGE_RES_IT page_res_it(page_res_);
while (page_res_it.word() != nullptr) {
WERD_RES *word_res = page_res_it.word();
GenericVector<TBOX> boxes;
tesseract_->MaximallyChopWord(boxes, page_res_it.block()->block,
page_res_it.row()->row, word_res);
page_res_it.forward();
}
return 0;
}
#endif // ndef DISABLED_LEGACY_ENGINE
// Takes ownership of the input pix.
void TessBaseAPI::SetInputImage(Pix* pix) { tesseract_->set_pix_original(pix); }
Pix* TessBaseAPI::GetInputImage() { return tesseract_->pix_original(); }
const char * TessBaseAPI::GetInputName() {
if (input_file_)
return input_file_->c_str();
return nullptr;
}
const char * TessBaseAPI::GetDatapath() {
return tesseract_->datadir.c_str();
}
int TessBaseAPI::GetSourceYResolution() {
return thresholder_->GetSourceYResolution();
}
// If flist exists, get data from there. Otherwise get data from buf.
// Seems convoluted, but is the easiest way I know of to meet multiple
// goals. Support streaming from stdin, and also work on platforms
// lacking fmemopen.
bool TessBaseAPI::ProcessPagesFileList(FILE *flist,
STRING *buf,
const char* retry_config,
int timeout_millisec,
TessResultRenderer* renderer,
int tessedit_page_number) {
if (!flist && !buf) return false;
int page = (tessedit_page_number >= 0) ? tessedit_page_number : 0;
char pagename[MAX_PATH];
GenericVector<STRING> lines;
if (!flist) {
buf->split('\n', &lines);
if (lines.empty()) return false;
}
// Skip to the requested page number.
for (int i = 0; i < page; i++) {
if (flist) {
if (fgets(pagename, sizeof(pagename), flist) == nullptr) break;
}
}
// Begin producing output
if (renderer && !renderer->BeginDocument(unknown_title_)) {
return false;
}
// Loop over all pages - or just the requested one
while (true) {
if (flist) {
if (fgets(pagename, sizeof(pagename), flist) == nullptr) break;
} else {
if (page >= lines.size()) break;
snprintf(pagename, sizeof(pagename), "%s", lines[page].c_str());
}
chomp_string(pagename);
Pix *pix = pixRead(pagename);
if (pix == nullptr) {
tprintf("Image file %s cannot be read!\n", pagename);
return false;
}
tprintf("Page %d : %s\n", page, pagename);
bool r = ProcessPage(pix, page, pagename, retry_config,
timeout_millisec, renderer);
pixDestroy(&pix);
if (!r) return false;
if (tessedit_page_number >= 0) break;
++page;
}
// Finish producing output
if (renderer && !renderer->EndDocument()) {
return false;
}
return true;
}
bool TessBaseAPI::ProcessPagesMultipageTiff(const l_uint8 *data,
size_t size,
const char* filename,
const char* retry_config,
int timeout_millisec,
TessResultRenderer* renderer,
int tessedit_page_number) {
#ifndef ANDROID_BUILD
Pix *pix = nullptr;
int page = (tessedit_page_number >= 0) ? tessedit_page_number : 0;
size_t offset = 0;
for (; ; ++page) {
if (tessedit_page_number >= 0)
page = tessedit_page_number;
pix = (data) ? pixReadMemFromMultipageTiff(data, size, &offset)
: pixReadFromMultipageTiff(filename, &offset);
if (pix == nullptr) break;
tprintf("Page %d\n", page + 1);
char page_str[kMaxIntSize];
snprintf(page_str, kMaxIntSize - 1, "%d", page);
SetVariable("applybox_page", page_str);
bool r = ProcessPage(pix, page, filename, retry_config,
timeout_millisec, renderer);
pixDestroy(&pix);
if (!r) return false;
if (tessedit_page_number >= 0) break;
if (!offset) break;
}
return true;
#else
return false;
#endif
}
// Master ProcessPages calls ProcessPagesInternal and then does any post-
// processing required due to being in a training mode.
bool TessBaseAPI::ProcessPages(const char* filename, const char* retry_config,
int timeout_millisec,
TessResultRenderer* renderer) {
bool result =
ProcessPagesInternal(filename, retry_config, timeout_millisec, renderer);
#ifndef DISABLED_LEGACY_ENGINE
if (result) {
if (tesseract_->tessedit_train_from_boxes &&
!tesseract_->WriteTRFile(*output_file_)) {
tprintf("Write of TR file failed: %s\n", output_file_->string());
return false;
}
}
#endif // ndef DISABLED_LEGACY_ENGINE
return result;
}
// In the ideal scenario, Tesseract will start working on data as soon
// as it can. For example, if you stream a filelist through stdin, we
// should start the OCR process as soon as the first filename is
// available. This is particularly useful when hooking Tesseract up to
// slow hardware such as a book scanning machine.
//
// Unfortunately there are tradeoffs. You can't seek on stdin. That
// makes automatic detection of datatype (TIFF? filelist? PNG?)
// impractical. So we support a command line flag to explicitly
// identify the scenario that really matters: filelists on
// stdin. We'll still do our best if the user likes pipes.
bool TessBaseAPI::ProcessPagesInternal(const char* filename,
const char* retry_config,
int timeout_millisec,
TessResultRenderer* renderer) {
bool stdInput = !strcmp(filename, "stdin") || !strcmp(filename, "-");
if (stdInput) {
#ifdef WIN32
if (_setmode(_fileno(stdin), _O_BINARY) == -1)
tprintf("ERROR: cin to binary: %s", strerror(errno));
#endif // WIN32
}
if (stream_filelist) {
return ProcessPagesFileList(stdin, nullptr, retry_config,
timeout_millisec, renderer,
tesseract_->tessedit_page_number);
}
// At this point we are officially in autodection territory.
// That means any data in stdin must be buffered, to make it
// seekable.
std::string buf;
const l_uint8 *data = nullptr;
if (stdInput) {
buf.assign((std::istreambuf_iterator<char>(std::cin)),
(std::istreambuf_iterator<char>()));
data = reinterpret_cast<const l_uint8 *>(buf.data());
} else {
// Check whether the input file can be read.
if (FILE* file = fopen(filename, "rb")) {
fclose(file);
} else {
fprintf(stderr, "Error, cannot read input file %s: %s\n",
filename, strerror(errno));
return false;
}
}
// Here is our autodetection
int format;
int r = (stdInput) ?
findFileFormatBuffer(data, &format) :
findFileFormat(filename, &format);
// Maybe we have a filelist
if (r != 0 || format == IFF_UNKNOWN) {
STRING s;
if (stdInput) {
s = buf.c_str();
} else {
std::ifstream t(filename);
std::string u((std::istreambuf_iterator<char>(t)),
std::istreambuf_iterator<char>());
s = u.c_str();
}
return ProcessPagesFileList(nullptr, &s, retry_config,
timeout_millisec, renderer,
tesseract_->tessedit_page_number);
}
// Maybe we have a TIFF which is potentially multipage
bool tiff = (format == IFF_TIFF || format == IFF_TIFF_PACKBITS ||
format == IFF_TIFF_RLE || format == IFF_TIFF_G3 ||
format == IFF_TIFF_G4 || format == IFF_TIFF_LZW ||
format == IFF_TIFF_ZIP);
// Fail early if we can, before producing any output
Pix *pix = nullptr;
if (!tiff) {
pix = (stdInput) ? pixReadMem(data, buf.size()) : pixRead(filename);
if (pix == nullptr) {
return false;
}
}
// Begin the output
if (renderer && !renderer->BeginDocument(unknown_title_)) {
pixDestroy(&pix);
return false;
}
// Produce output
r = (tiff) ?
ProcessPagesMultipageTiff(data, buf.size(), filename, retry_config,
timeout_millisec, renderer,
tesseract_->tessedit_page_number) :
ProcessPage(pix, 0, filename, retry_config,
timeout_millisec, renderer);
// Clean up memory as needed
pixDestroy(&pix);
// End the output
if (!r || (renderer && !renderer->EndDocument())) {
return false;
}
return true;
}
bool TessBaseAPI::ProcessPage(Pix* pix, int page_index, const char* filename,
const char* retry_config, int timeout_millisec,
TessResultRenderer* renderer) {
SetInputName(filename);
SetImage(pix);
bool failed = false;
if (tesseract_->tessedit_pageseg_mode == PSM_AUTO_ONLY) {
// Disabled character recognition
PageIterator* it = AnalyseLayout();
if (it == nullptr) {
failed = true;
} else {
delete it;
}
} else if (tesseract_->tessedit_pageseg_mode == PSM_OSD_ONLY) {
failed = FindLines() != 0;
} else if (timeout_millisec > 0) {
// Running with a timeout.
ETEXT_DESC monitor;
monitor.cancel = nullptr;
monitor.cancel_this = nullptr;
monitor.set_deadline_msecs(timeout_millisec);
// Now run the main recognition.
failed = Recognize(&monitor) < 0;
} else {
// Normal layout and character recognition with no timeout.
failed = Recognize(nullptr) < 0;
}
if (tesseract_->tessedit_write_images) {
#ifndef ANDROID_BUILD
Pix* page_pix = GetThresholdedImage();
pixWrite("tessinput.tif", page_pix, IFF_TIFF_G4);
#endif // ANDROID_BUILD
}
if (failed && retry_config != nullptr && retry_config[0] != '\0') {
// Save current config variables before switching modes.
FILE* fp = fopen(kOldVarsFile, "wb");
if (fp == nullptr) {
tprintf("Error, failed to open file \"%s\"\n", kOldVarsFile);
} else {
PrintVariables(fp);
fclose(fp);
}
// Switch to alternate mode for retry.
ReadConfigFile(retry_config);
SetImage(pix);
Recognize(nullptr);
// Restore saved config variables.
ReadConfigFile(kOldVarsFile);
}
if (renderer && !failed) {
failed = !renderer->AddImage(this);
}
return !failed;
}
/**
* Get a left-to-right iterator to the results of LayoutAnalysis and/or
* Recognize. The returned iterator must be deleted after use.
*/
LTRResultIterator* TessBaseAPI::GetLTRIterator() {
if (tesseract_ == nullptr || page_res_ == nullptr)
return nullptr;
return new LTRResultIterator(
page_res_, tesseract_,
thresholder_->GetScaleFactor(), thresholder_->GetScaledYResolution(),
rect_left_, rect_top_, rect_width_, rect_height_);
}
/**
* Get a reading-order iterator to the results of LayoutAnalysis and/or
* Recognize. The returned iterator must be deleted after use.
* WARNING! This class points to data held within the TessBaseAPI class, and
* therefore can only be used while the TessBaseAPI class still exists and
* has not been subjected to a call of Init, SetImage, Recognize, Clear, End
* DetectOS, or anything else that changes the internal PAGE_RES.
*/
ResultIterator* TessBaseAPI::GetIterator() {
if (tesseract_ == nullptr || page_res_ == nullptr)
return nullptr;
return ResultIterator::StartOfParagraph(LTRResultIterator(
page_res_, tesseract_,
thresholder_->GetScaleFactor(), thresholder_->GetScaledYResolution(),
rect_left_, rect_top_, rect_width_, rect_height_));
}
/**
* Get a mutable iterator to the results of LayoutAnalysis and/or Recognize.
* The returned iterator must be deleted after use.
* WARNING! This class points to data held within the TessBaseAPI class, and
* therefore can only be used while the TessBaseAPI class still exists and
* has not been subjected to a call of Init, SetImage, Recognize, Clear, End
* DetectOS, or anything else that changes the internal PAGE_RES.
*/
MutableIterator* TessBaseAPI::GetMutableIterator() {
if (tesseract_ == nullptr || page_res_ == nullptr)
return nullptr;
return new MutableIterator(page_res_, tesseract_,
thresholder_->GetScaleFactor(),
thresholder_->GetScaledYResolution(),
rect_left_, rect_top_, rect_width_, rect_height_);
}
/** Make a text string from the internal data structures. */
char* TessBaseAPI::GetUTF8Text() {
if (tesseract_ == nullptr ||
(!recognition_done_ && Recognize(nullptr) < 0))
return nullptr;
STRING text("");
ResultIterator *it = GetIterator();
do {
if (it->Empty(RIL_PARA)) continue;
const std::unique_ptr<const char[]> para_text(it->GetUTF8Text(RIL_PARA));
text += para_text.get();
} while (it->Next(RIL_PARA));
char* result = new char[text.length() + 1];
strncpy(result, text.string(), text.length() + 1);
delete it;
return result;
}
static void AddBoxToTSV(const PageIterator* it, PageIteratorLevel level,
STRING* text) {
int left, top, right, bottom;
it->BoundingBox(level, &left, &top, &right, &bottom);
text->add_str_int("\t", left);
text->add_str_int("\t", top);
text->add_str_int("\t", right - left);
text->add_str_int("\t", bottom - top);
}
/**
* Make a TSV-formatted string from the internal data structures.
* page_number is 0-based but will appear in the output as 1-based.
* Returned string must be freed with the delete [] operator.
*/
char* TessBaseAPI::GetTSVText(int page_number) {
if (tesseract_ == nullptr || (page_res_ == nullptr && Recognize(nullptr) < 0))
return nullptr;
int lcnt = 1, bcnt = 1, pcnt = 1, wcnt = 1;
int page_id = page_number + 1; // we use 1-based page numbers.
STRING tsv_str("");
int page_num = page_id;
int block_num = 0;
int par_num = 0;
int line_num = 0;
int word_num = 0;
tsv_str.add_str_int("1\t", page_num); // level 1 - page
tsv_str.add_str_int("\t", block_num);
tsv_str.add_str_int("\t", par_num);
tsv_str.add_str_int("\t", line_num);
tsv_str.add_str_int("\t", word_num);
tsv_str.add_str_int("\t", rect_left_);
tsv_str.add_str_int("\t", rect_top_);
tsv_str.add_str_int("\t", rect_width_);
tsv_str.add_str_int("\t", rect_height_);
tsv_str += "\t-1\t\n";
ResultIterator* res_it = GetIterator();
while (!res_it->Empty(RIL_BLOCK)) {
if (res_it->Empty(RIL_WORD)) {
res_it->Next(RIL_WORD);
continue;
}
// Add rows for any new block/paragraph/textline.
if (res_it->IsAtBeginningOf(RIL_BLOCK)) {
block_num++;
par_num = 0;
line_num = 0;
word_num = 0;
tsv_str.add_str_int("2\t", page_num); // level 2 - block
tsv_str.add_str_int("\t", block_num);
tsv_str.add_str_int("\t", par_num);
tsv_str.add_str_int("\t", line_num);
tsv_str.add_str_int("\t", word_num);
AddBoxToTSV(res_it, RIL_BLOCK, &tsv_str);
tsv_str += "\t-1\t\n"; // end of row for block
}
if (res_it->IsAtBeginningOf(RIL_PARA)) {
par_num++;
line_num = 0;
word_num = 0;
tsv_str.add_str_int("3\t", page_num); // level 3 - paragraph
tsv_str.add_str_int("\t", block_num);
tsv_str.add_str_int("\t", par_num);
tsv_str.add_str_int("\t", line_num);
tsv_str.add_str_int("\t", word_num);
AddBoxToTSV(res_it, RIL_PARA, &tsv_str);
tsv_str += "\t-1\t\n"; // end of row for para
}
if (res_it->IsAtBeginningOf(RIL_TEXTLINE)) {
line_num++;
word_num = 0;
tsv_str.add_str_int("4\t", page_num); // level 4 - line
tsv_str.add_str_int("\t", block_num);
tsv_str.add_str_int("\t", par_num);
tsv_str.add_str_int("\t", line_num);
tsv_str.add_str_int("\t", word_num);
AddBoxToTSV(res_it, RIL_TEXTLINE, &tsv_str);
tsv_str += "\t-1\t\n"; // end of row for line
}
// Now, process the word...
int left, top, right, bottom;
res_it->BoundingBox(RIL_WORD, &left, &top, &right, &bottom);
word_num++;
tsv_str.add_str_int("5\t", page_num); // level 5 - word
tsv_str.add_str_int("\t", block_num);
tsv_str.add_str_int("\t", par_num);
tsv_str.add_str_int("\t", line_num);
tsv_str.add_str_int("\t", word_num);
tsv_str.add_str_int("\t", left);
tsv_str.add_str_int("\t", top);
tsv_str.add_str_int("\t", right - left);
tsv_str.add_str_int("\t", bottom - top);
tsv_str.add_str_int("\t", res_it->Confidence(RIL_WORD));
tsv_str += "\t";
// Increment counts if at end of block/paragraph/textline.
if (res_it->IsAtFinalElement(RIL_TEXTLINE, RIL_WORD)) lcnt++;
if (res_it->IsAtFinalElement(RIL_PARA, RIL_WORD)) pcnt++;
if (res_it->IsAtFinalElement(RIL_BLOCK, RIL_WORD)) bcnt++;
do {
tsv_str +=
std::unique_ptr<const char[]>(res_it->GetUTF8Text(RIL_SYMBOL)).get();
res_it->Next(RIL_SYMBOL);
} while (!res_it->Empty(RIL_BLOCK) && !res_it->IsAtBeginningOf(RIL_WORD));
tsv_str += "\n"; // end of row
wcnt++;
}
char* ret = new char[tsv_str.length() + 1];
strcpy(ret, tsv_str.string());
delete res_it;
return ret;
}
/** The 5 numbers output for each box (the usual 4 and a page number.) */
const int kNumbersPerBlob = 5;
/**
* The number of bytes taken by each number. Since we use int16_t for ICOORD,
* assume only 5 digits max.
*/
const int kBytesPerNumber = 5;
/**
* Multiplier for max expected textlength assumes (kBytesPerNumber + space)
* * kNumbersPerBlob plus the newline. Add to this the
* original UTF8 characters, and one kMaxBytesPerLine for safety.
*/
const int kBytesPerBoxFileLine = (kBytesPerNumber + 1) * kNumbersPerBlob + 1;
/** Max bytes in the decimal representation of int64_t. */
const int kBytesPer64BitNumber = 20;
/**
* A maximal single box could occupy kNumbersPerBlob numbers at
* kBytesPer64BitNumber digits (if someone sneaks in a 64 bit value) and a
* space plus the newline and the maximum length of a UNICHAR.
* Test against this on each iteration for safety.
*/
const int kMaxBytesPerLine = kNumbersPerBlob * (kBytesPer64BitNumber + 1) + 1 +
UNICHAR_LEN;
/**
* The recognized text is returned as a char* which is coded
* as a UTF8 box file.
* page_number is a 0-base page index that will appear in the box file.
* Returned string must be freed with the delete [] operator.
*/
char* TessBaseAPI::GetBoxText(int page_number) {
if (tesseract_ == nullptr ||
(!recognition_done_ && Recognize(nullptr) < 0))
return nullptr;
int blob_count;
int utf8_length = TextLength(&blob_count);
int total_length = blob_count * kBytesPerBoxFileLine + utf8_length +
kMaxBytesPerLine;
char* result = new char[total_length];
result[0] = '\0';
int output_length = 0;
LTRResultIterator* it = GetLTRIterator();
do {
int left, top, right, bottom;
if (it->BoundingBox(RIL_SYMBOL, &left, &top, &right, &bottom)) {
const std::unique_ptr</*non-const*/ char[]> text(
it->GetUTF8Text(RIL_SYMBOL));
// Tesseract uses space for recognition failure. Fix to a reject
// character, kTesseractReject so we don't create illegal box files.
for (int i = 0; text[i] != '\0'; ++i) {
if (text[i] == ' ')
text[i] = kTesseractReject;
}
snprintf(result + output_length, total_length - output_length,
"%s %d %d %d %d %d\n", text.get(), left, image_height_ - bottom,
right, image_height_ - top, page_number);
output_length += strlen(result + output_length);
// Just in case...
if (output_length + kMaxBytesPerLine > total_length)
break;
}
} while (it->Next(RIL_SYMBOL));
delete it;
return result;
}
/**
* Conversion table for non-latin characters.
* Maps characters out of the latin set into the latin set.
* TODO(rays) incorporate this translation into unicharset.
*/
const int kUniChs[] = {
0x20ac, 0x201c, 0x201d, 0x2018, 0x2019, 0x2022, 0x2014, 0
};
/** Latin chars corresponding to the unicode chars above. */
const int kLatinChs[] = {
0x00a2, 0x0022, 0x0022, 0x0027, 0x0027, 0x00b7, 0x002d, 0
};
/**
* The recognized text is returned as a char* which is coded
* as UNLV format Latin-1 with specific reject and suspect codes.
* Returned string must be freed with the delete [] operator.
*/
char* TessBaseAPI::GetUNLVText() {
if (tesseract_ == nullptr ||
(!recognition_done_ && Recognize(nullptr) < 0))
return nullptr;
bool tilde_crunch_written = false;
bool last_char_was_newline = true;
bool last_char_was_tilde = false;
int total_length = TextLength(nullptr);
PAGE_RES_IT page_res_it(page_res_);
char* result = new char[total_length];
char* ptr = result;
for (page_res_it.restart_page(); page_res_it.word () != nullptr;
page_res_it.forward()) {
WERD_RES *word = page_res_it.word();
// Process the current word.
if (word->unlv_crunch_mode != CR_NONE) {
if (word->unlv_crunch_mode != CR_DELETE &&
(!tilde_crunch_written ||
(word->unlv_crunch_mode == CR_KEEP_SPACE &&
word->word->space() > 0 &&
!word->word->flag(W_FUZZY_NON) &&
!word->word->flag(W_FUZZY_SP)))) {
if (!word->word->flag(W_BOL) &&
word->word->space() > 0 &&
!word->word->flag(W_FUZZY_NON) &&
!word->word->flag(W_FUZZY_SP)) {
/* Write a space to separate from preceding good text */
*ptr++ = ' ';
last_char_was_tilde = false;
}
if (!last_char_was_tilde) {
// Write a reject char.
last_char_was_tilde = true;
*ptr++ = kUNLVReject;
tilde_crunch_written = true;
last_char_was_newline = false;
}
}
} else {
// NORMAL PROCESSING of non tilde crunched words.
tilde_crunch_written = false;
tesseract_->set_unlv_suspects(word);
const char* wordstr = word->best_choice->unichar_string().string();
const STRING& lengths = word->best_choice->unichar_lengths();
int length = lengths.length();
int i = 0;
int offset = 0;
if (last_char_was_tilde &&
word->word->space() == 0 && wordstr[offset] == ' ') {
// Prevent adjacent tilde across words - we know that adjacent tildes
// within words have been removed.
// Skip the first character.
offset = lengths[i++];
}
if (i < length && wordstr[offset] != 0) {
if (!last_char_was_newline)
*ptr++ = ' ';
else
last_char_was_newline = false;
for (; i < length; offset += lengths[i++]) {
if (wordstr[offset] == ' ' ||
wordstr[offset] == kTesseractReject) {
*ptr++ = kUNLVReject;
last_char_was_tilde = true;
} else {
if (word->reject_map[i].rejected())
*ptr++ = kUNLVSuspect;
UNICHAR ch(wordstr + offset, lengths[i]);
int uni_ch = ch.first_uni();
for (int j = 0; kUniChs[j] != 0; ++j) {
if (kUniChs[j] == uni_ch) {
uni_ch = kLatinChs[j];
break;
}
}
if (uni_ch <= 0xff) {
*ptr++ = static_cast<char>(uni_ch);
last_char_was_tilde = false;
} else {
*ptr++ = kUNLVReject;
last_char_was_tilde = true;
}
}
}
}
}
if (word->word->flag(W_EOL) && !last_char_was_newline) {
/* Add a new line output */
*ptr++ = '\n';
tilde_crunch_written = false;
last_char_was_newline = true;
last_char_was_tilde = false;
}
}
*ptr++ = '\n';
*ptr = '\0';
return result;
}
#ifndef DISABLED_LEGACY_ENGINE
/**
* Detect the orientation of the input image and apparent script (alphabet).
* orient_deg is the detected clockwise rotation of the input image in degrees
* (0, 90, 180, 270)
* orient_conf is the confidence (15.0 is reasonably confident)
* script_name is an ASCII string, the name of the script, e.g. "Latin"
* script_conf is confidence level in the script
* Returns true on success and writes values to each parameter as an output
*/
bool TessBaseAPI::DetectOrientationScript(int* orient_deg, float* orient_conf,
const char** script_name,
float* script_conf) {
OSResults osr;
bool osd = DetectOS(&osr);
if (!osd) {
return false;
}
int orient_id = osr.best_result.orientation_id;
int script_id = osr.get_best_script(orient_id);
if (orient_conf) *orient_conf = osr.best_result.oconfidence;
if (orient_deg) *orient_deg = orient_id * 90; // convert quadrant to degrees
if (script_name) {
const char* script = osr.unicharset->get_script_from_script_id(script_id);
*script_name = script;
}
if (script_conf) *script_conf = osr.best_result.sconfidence;
return true;
}
/**
* The recognized text is returned as a char* which is coded
* as UTF8 and must be freed with the delete [] operator.
* page_number is a 0-based page index that will appear in the osd file.
*/
char* TessBaseAPI::GetOsdText(int page_number) {
int orient_deg;
float orient_conf;
const char* script_name;
float script_conf;
if (!DetectOrientationScript(&orient_deg, &orient_conf, &script_name,
&script_conf))
return nullptr;
// clockwise rotation needed to make the page upright
int rotate = OrientationIdToValue(orient_deg / 90);
std::stringstream stream;
// Use "C" locale (needed for float values orient_conf and script_conf).
stream.imbue(std::locale::classic());
// Use fixed notation with 2 digits after the decimal point for float values.
stream.precision(2);
stream
<< std::fixed
<< "Page number: " << page_number << "\n"
<< "Orientation in degrees: " << orient_deg << "\n"
<< "Rotate: " << rotate << "\n"
<< "Orientation confidence: " << orient_conf << "\n"
<< "Script: " << script_name << "\n"
<< "Script confidence: " << script_conf << "\n";
const std::string& text = stream.str();
char* result = new char[text.length() + 1];
strcpy(result, text.c_str());
return result;
}
#endif // ndef DISABLED_LEGACY_ENGINE
/** Returns the average word confidence for Tesseract page result. */
int TessBaseAPI::MeanTextConf() {
int* conf = AllWordConfidences();
if (!conf) return 0;
int sum = 0;
int *pt = conf;
while (*pt >= 0) sum += *pt++;
if (pt != conf) sum /= pt - conf;
delete [] conf;
return sum;
}
/** Returns an array of all word confidences, terminated by -1. */
int* TessBaseAPI::AllWordConfidences() {
if (tesseract_ == nullptr ||
(!recognition_done_ && Recognize(nullptr) < 0))
return nullptr;
int n_word = 0;
PAGE_RES_IT res_it(page_res_);
for (res_it.restart_page(); res_it.word() != nullptr; res_it.forward())
n_word++;
int* conf = new int[n_word+1];
n_word = 0;
for (res_it.restart_page(); res_it.word() != nullptr; res_it.forward()) {
WERD_RES *word = res_it.word();
WERD_CHOICE* choice = word->best_choice;
int w_conf = static_cast<int>(100 + 5 * choice->certainty());
// This is the eq for converting Tesseract confidence to 1..100
if (w_conf < 0) w_conf = 0;
if (w_conf > 100) w_conf = 100;
conf[n_word++] = w_conf;
}
conf[n_word] = -1;
return conf;
}
#ifndef DISABLED_LEGACY_ENGINE
/**
* Applies the given word to the adaptive classifier if possible.
* The word must be SPACE-DELIMITED UTF-8 - l i k e t h i s , so it can
* tell the boundaries of the graphemes.
* Assumes that SetImage/SetRectangle have been used to set the image
* to the given word. The mode arg should be PSM_SINGLE_WORD or
* PSM_CIRCLE_WORD, as that will be used to control layout analysis.
* The currently set PageSegMode is preserved.
* Returns false if adaption was not possible for some reason.
*/
bool TessBaseAPI::AdaptToWordStr(PageSegMode mode, const char* wordstr) {
int debug = 0;
GetIntVariable("applybox_debug", &debug);
bool success = true;
PageSegMode current_psm = GetPageSegMode();
SetPageSegMode(mode);
SetVariable("classify_enable_learning", "0");
const std::unique_ptr<const char[]> text(GetUTF8Text());
if (debug) {
tprintf("Trying to adapt \"%s\" to \"%s\"\n", text.get(), wordstr);
}
if (text != nullptr) {
PAGE_RES_IT it(page_res_);
WERD_RES* word_res = it.word();
if (word_res != nullptr) {
word_res->word->set_text(wordstr);
// Check to see if text matches wordstr.
int w = 0;
int t;
for (t = 0; text[t] != '\0'; ++t) {
if (text[t] == '\n' || text[t] == ' ')
continue;
while (wordstr[w] == ' ') ++w;
if (text[t] != wordstr[w])
break;
++w;
}
if (text[t] != '\0' || wordstr[w] != '\0') {
// No match.
delete page_res_;
GenericVector<TBOX> boxes;
page_res_ = tesseract_->SetupApplyBoxes(boxes, block_list_);
tesseract_->ReSegmentByClassification(page_res_);
tesseract_->TidyUp(page_res_);
PAGE_RES_IT pr_it(page_res_);
if (pr_it.word() == nullptr)
success = false;
else
word_res = pr_it.word();
} else {
word_res->BestChoiceToCorrectText();
}
if (success) {
tesseract_->EnableLearning = true;
tesseract_->LearnWord(nullptr, word_res);
}
} else {
success = false;
}
} else {
success = false;
}
SetPageSegMode(current_psm);
return success;
}
#endif // ndef DISABLED_LEGACY_ENGINE
/**
* Free up recognition results and any stored image data, without actually
* freeing any recognition data that would be time-consuming to reload.
* Afterwards, you must call SetImage or TesseractRect before doing
* any Recognize or Get* operation.
*/
void TessBaseAPI::Clear() {
if (thresholder_ != nullptr)
thresholder_->Clear();
ClearResults();
if (tesseract_ != nullptr) SetInputImage(nullptr);
}
/**
* Close down tesseract and free up all memory. End() is equivalent to
* destructing and reconstructing your TessBaseAPI.
* Once End() has been used, none of the other API functions may be used
* other than Init and anything declared above it in the class definition.
*/
void TessBaseAPI::End() {
Clear();
delete thresholder_;
thresholder_ = nullptr;
delete page_res_;
page_res_ = nullptr;
delete block_list_;
block_list_ = nullptr;
if (paragraph_models_ != nullptr) {
paragraph_models_->delete_data_pointers();
delete paragraph_models_;
paragraph_models_ = nullptr;
}
if (osd_tesseract_ == tesseract_) osd_tesseract_ = nullptr;
delete tesseract_;
tesseract_ = nullptr;
delete osd_tesseract_;
osd_tesseract_ = nullptr;
delete equ_detect_;
equ_detect_ = nullptr;
delete input_file_;
input_file_ = nullptr;
delete output_file_;
output_file_ = nullptr;
delete datapath_;
datapath_ = nullptr;
delete language_;
language_ = nullptr;
}
// Clear any library-level memory caches.
// There are a variety of expensive-to-load constant data structures (mostly
// language dictionaries) that are cached globally -- surviving the Init()
// and End() of individual TessBaseAPI's. This function allows the clearing
// of these caches.
void TessBaseAPI::ClearPersistentCache() {
Dict::GlobalDawgCache()->DeleteUnusedDawgs();
}
/**
* Check whether a word is valid according to Tesseract's language model
* returns 0 if the word is invalid, non-zero if valid
*/
int TessBaseAPI::IsValidWord(const char *word) {
return tesseract_->getDict().valid_word(word);
}
// Returns true if utf8_character is defined in the UniCharset.
bool TessBaseAPI::IsValidCharacter(const char *utf8_character) {
return tesseract_->unicharset.contains_unichar(utf8_character);
}
// TODO(rays) Obsolete this function and replace with a more aptly named
// function that returns image coordinates rather than tesseract coordinates.
bool TessBaseAPI::GetTextDirection(int* out_offset, float* out_slope) {
PageIterator* it = AnalyseLayout();
if (it == nullptr) {
return false;
}
int x1, x2, y1, y2;
it->Baseline(RIL_TEXTLINE, &x1, &y1, &x2, &y2);
// Calculate offset and slope (NOTE: Kind of ugly)
if (x2 <= x1) x2 = x1 + 1;
// Convert the point pair to slope/offset of the baseline (in image coords.)
*out_slope = static_cast<float>(y2 - y1) / (x2 - x1);
*out_offset = static_cast<int>(y1 - *out_slope * x1);
// Get the y-coord of the baseline at the left and right edges of the
// textline's bounding box.
int left, top, right, bottom;
if (!it->BoundingBox(RIL_TEXTLINE, &left, &top, &right, &bottom)) {
delete it;
return false;
}
int left_y = IntCastRounded(*out_slope * left + *out_offset);
int right_y = IntCastRounded(*out_slope * right + *out_offset);
// Shift the baseline down so it passes through the nearest bottom-corner
// of the textline's bounding box. This is the difference between the y
// at the lowest (max) edge of the box and the actual box bottom.
*out_offset += bottom - std::max(left_y, right_y);
// Switch back to bottom-up tesseract coordinates. Requires negation of
// the slope and height - offset for the offset.
*out_slope = -*out_slope;
*out_offset = rect_height_ - *out_offset;
delete it;
return true;
}
/** Sets Dict::letter_is_okay_ function to point to the given function. */
void TessBaseAPI::SetDictFunc(DictFunc f) {
if (tesseract_ != nullptr) {
tesseract_->getDict().letter_is_okay_ = f;
}
}
/**
* Sets Dict::probability_in_context_ function to point to the given
* function.
*
* @param f A single function that returns the probability of the current
* "character" (in general a utf-8 string), given the context of a previous
* utf-8 string.
*/
void TessBaseAPI::SetProbabilityInContextFunc(ProbabilityInContextFunc f) {
if (tesseract_ != nullptr) {
tesseract_->getDict().probability_in_context_ = f;
// Set it for the sublangs too.
int num_subs = tesseract_->num_sub_langs();
for (int i = 0; i < num_subs; ++i) {
tesseract_->get_sub_lang(i)->getDict().probability_in_context_ = f;
}
}
}
#ifndef DISABLED_LEGACY_ENGINE
/** Sets Wordrec::fill_lattice_ function to point to the given function. */
void TessBaseAPI::SetFillLatticeFunc(FillLatticeFunc f) {
if (tesseract_ != nullptr) tesseract_->fill_lattice_ = f;
}
#endif // ndef DISABLED_LEGACY_ENGINE
/** Common code for setting the image. */
bool TessBaseAPI::InternalSetImage() {
if (tesseract_ == nullptr) {
tprintf("Please call Init before attempting to set an image.\n");
return false;
}
if (thresholder_ == nullptr)
thresholder_ = new ImageThresholder;
ClearResults();
return true;
}
/**
* Run the thresholder to make the thresholded image, returned in pix,
* which must not be nullptr. *pix must be initialized to nullptr, or point
* to an existing pixDestroyable Pix.
* The usual argument to Threshold is Tesseract::mutable_pix_binary().
*/
bool TessBaseAPI::Threshold(Pix** pix) {
ASSERT_HOST(pix != nullptr);
if (*pix != nullptr)
pixDestroy(pix);
// Zero resolution messes up the algorithms, so make sure it is credible.
int user_dpi = 0;
GetIntVariable("user_defined_dpi", &user_dpi);
int y_res = thresholder_->GetScaledYResolution();
if (user_dpi && (user_dpi < kMinCredibleResolution ||
user_dpi > kMaxCredibleResolution)) {
tprintf("Warning: User defined image dpi is outside of expected range "
"(%d - %d)!\n",
kMinCredibleResolution, kMaxCredibleResolution);
}
// Always use user defined dpi
if (user_dpi) {
thresholder_->SetSourceYResolution(user_dpi);
} else if (y_res < kMinCredibleResolution ||
y_res > kMaxCredibleResolution) {
tprintf("Warning: Invalid resolution %d dpi. Using %d instead.\n",
y_res, kMinCredibleResolution);
thresholder_->SetSourceYResolution(kMinCredibleResolution);
}
auto pageseg_mode =
static_cast<PageSegMode>(
static_cast<int>(tesseract_->tessedit_pageseg_mode));
if (!thresholder_->ThresholdToPix(pageseg_mode, pix)) return false;
thresholder_->GetImageSizes(&rect_left_, &rect_top_,
&rect_width_, &rect_height_,
&image_width_, &image_height_);
if (!thresholder_->IsBinary()) {
tesseract_->set_pix_thresholds(thresholder_->GetPixRectThresholds());
tesseract_->set_pix_grey(thresholder_->GetPixRectGrey());
} else {
tesseract_->set_pix_thresholds(nullptr);
tesseract_->set_pix_grey(nullptr);
}
// Set the internal resolution that is used for layout parameters from the
// estimated resolution, rather than the image resolution, which may be
// fabricated, but we will use the image resolution, if there is one, to
// report output point sizes.
int estimated_res = ClipToRange(thresholder_->GetScaledEstimatedResolution(),
kMinCredibleResolution,
kMaxCredibleResolution);
if (estimated_res != thresholder_->GetScaledEstimatedResolution()) {
tprintf("Estimated internal resolution %d out of range! "
"Corrected to %d.\n",
thresholder_->GetScaledEstimatedResolution(), estimated_res);
}
tesseract_->set_source_resolution(estimated_res);
SavePixForCrash(estimated_res, *pix);
return true;
}
/** Find lines from the image making the BLOCK_LIST. */
int TessBaseAPI::FindLines() {
if (thresholder_ == nullptr || thresholder_->IsEmpty()) {
tprintf("Please call SetImage before attempting recognition.\n");
return -1;
}
if (recognition_done_)
ClearResults();
if (!block_list_->empty()) {
return 0;
}
if (tesseract_ == nullptr) {
tesseract_ = new Tesseract;
#ifndef DISABLED_LEGACY_ENGINE
tesseract_->InitAdaptiveClassifier(nullptr);
#endif
}
if (tesseract_->pix_binary() == nullptr &&
!Threshold(tesseract_->mutable_pix_binary())) {
return -1;
}
tesseract_->PrepareForPageseg();
#ifndef DISABLED_LEGACY_ENGINE
if (tesseract_->textord_equation_detect) {
if (equ_detect_ == nullptr && datapath_ != nullptr) {
equ_detect_ = new EquationDetect(datapath_->string(), nullptr);
}
if (equ_detect_ == nullptr) {
tprintf("Warning: Could not set equation detector\n");
} else {
tesseract_->SetEquationDetect(equ_detect_);
}
}
#endif // ndef DISABLED_LEGACY_ENGINE
Tesseract* osd_tess = osd_tesseract_;
OSResults osr;
if (PSM_OSD_ENABLED(tesseract_->tessedit_pageseg_mode) &&
osd_tess == nullptr) {
if (strcmp(language_->string(), "osd") == 0) {
osd_tess = tesseract_;
} else {
osd_tesseract_ = new Tesseract;
TessdataManager mgr(reader_);
if (datapath_ == nullptr) {
tprintf("Warning: Auto orientation and script detection requested,"
" but data path is undefined\n");
delete osd_tesseract_;
osd_tesseract_ = nullptr;
} else if (osd_tesseract_->init_tesseract(datapath_->string(), nullptr,
"osd", OEM_TESSERACT_ONLY,
nullptr, 0, nullptr, nullptr,
false, &mgr) == 0) {
osd_tess = osd_tesseract_;
osd_tesseract_->set_source_resolution(
thresholder_->GetSourceYResolution());
} else {
tprintf("Warning: Auto orientation and script detection requested,"
" but osd language failed to load\n");
delete osd_tesseract_;
osd_tesseract_ = nullptr;
}
}
}
if (tesseract_->SegmentPage(input_file_, block_list_, osd_tess, &osr) < 0)
return -1;
// If Devanagari is being recognized, we use different images for page seg
// and for OCR.
tesseract_->PrepareForTessOCR(block_list_, osd_tess, &osr);
return 0;
}
/** Delete the pageres and clear the block list ready for a new page. */
void TessBaseAPI::ClearResults() {
if (tesseract_ != nullptr) {
tesseract_->Clear();
}
delete page_res_;
page_res_ = nullptr;
recognition_done_ = false;
if (block_list_ == nullptr)
block_list_ = new BLOCK_LIST;
else
block_list_->clear();
if (paragraph_models_ != nullptr) {
paragraph_models_->delete_data_pointers();
delete paragraph_models_;
paragraph_models_ = nullptr;
}
SavePixForCrash(0, nullptr);
}
/**
* Return the length of the output text string, as UTF8, assuming
* liberally two spacing marks after each word (as paragraphs end with two
* newlines), and assuming a single character reject marker for each rejected
* character.
* Also return the number of recognized blobs in blob_count.
*/
int TessBaseAPI::TextLength(int* blob_count) {
if (tesseract_ == nullptr || page_res_ == nullptr)
return 0;
PAGE_RES_IT page_res_it(page_res_);
int total_length = 2;
int total_blobs = 0;
// Iterate over the data structures to extract the recognition result.
for (page_res_it.restart_page(); page_res_it.word () != nullptr;
page_res_it.forward()) {
WERD_RES *word = page_res_it.word();
WERD_CHOICE* choice = word->best_choice;
if (choice != nullptr) {
total_blobs += choice->length() + 2;
total_length += choice->unichar_string().length() + 2;
for (int i = 0; i < word->reject_map.length(); ++i) {
if (word->reject_map[i].rejected())
++total_length;
}
}
}
if (blob_count != nullptr)
*blob_count = total_blobs;
return total_length;
}
#ifndef DISABLED_LEGACY_ENGINE
/**
* Estimates the Orientation And Script of the image.
* Returns true if the image was processed successfully.
*/
bool TessBaseAPI::DetectOS(OSResults* osr) {
if (tesseract_ == nullptr)
return false;
ClearResults();
if (tesseract_->pix_binary() == nullptr &&
!Threshold(tesseract_->mutable_pix_binary())) {
return false;
}
if (input_file_ == nullptr)
input_file_ = new STRING(kInputFile);
return orientation_and_script_detection(*input_file_, osr, tesseract_) > 0;
}
#endif // ndef DISABLED_LEGACY_ENGINE
void TessBaseAPI::set_min_orientation_margin(double margin) {
tesseract_->min_orientation_margin.set_value(margin);
}
/**
* Return text orientation of each block as determined in an earlier page layout
* analysis operation. Orientation is returned as the number of ccw 90-degree
* rotations (in [0..3]) required to make the text in the block upright
* (readable). Note that this may not necessary be the block orientation
* preferred for recognition (such as the case of vertical CJK text).
*
* Also returns whether the text in the block is believed to have vertical
* writing direction (when in an upright page orientation).
*
* The returned array is of length equal to the number of text blocks, which may
* be less than the total number of blocks. The ordering is intended to be
* consistent with GetTextLines().
*/
void TessBaseAPI::GetBlockTextOrientations(int** block_orientation,
bool** vertical_writing) {
delete[] *block_orientation;
*block_orientation = nullptr;
delete[] *vertical_writing;
*vertical_writing = nullptr;
BLOCK_IT block_it(block_list_);
block_it.move_to_first();
int num_blocks = 0;
for (block_it.mark_cycle_pt(); !block_it.cycled_list(); block_it.forward()) {
if (!block_it.data()->pdblk.poly_block()->IsText()) {
continue;
}
++num_blocks;
}
if (!num_blocks) {
tprintf("WARNING: Found no blocks\n");
return;
}
*block_orientation = new int[num_blocks];
*vertical_writing = new bool[num_blocks];
block_it.move_to_first();
int i = 0;
for (block_it.mark_cycle_pt(); !block_it.cycled_list();
block_it.forward()) {
if (!block_it.data()->pdblk.poly_block()->IsText()) {
continue;
}
FCOORD re_rotation = block_it.data()->re_rotation();
float re_theta = re_rotation.angle();
FCOORD classify_rotation = block_it.data()->classify_rotation();
float classify_theta = classify_rotation.angle();
double rot_theta = - (re_theta - classify_theta) * 2.0 / M_PI;
if (rot_theta < 0) rot_theta += 4;
int num_rotations = static_cast<int>(rot_theta + 0.5);
(*block_orientation)[i] = num_rotations;
// The classify_rotation is non-zero only if the text has vertical
// writing direction.
(*vertical_writing)[i] = classify_rotation.y() != 0.0f;
++i;
}
}
void TessBaseAPI::DetectParagraphs(bool after_text_recognition) {
int debug_level = 0;
GetIntVariable("paragraph_debug_level", &debug_level);
if (paragraph_models_ == nullptr)
paragraph_models_ = new GenericVector<ParagraphModel*>;
MutableIterator *result_it = GetMutableIterator();
do { // Detect paragraphs for this block
GenericVector<ParagraphModel *> models;
::tesseract::DetectParagraphs(debug_level, after_text_recognition,
result_it, &models);
*paragraph_models_ += models;
} while (result_it->Next(RIL_BLOCK));
delete result_it;
}
/** This method returns the string form of the specified unichar. */
const char* TessBaseAPI::GetUnichar(int unichar_id) {
return tesseract_->unicharset.id_to_unichar(unichar_id);
}
/** Return the pointer to the i-th dawg loaded into tesseract_ object. */
const Dawg *TessBaseAPI::GetDawg(int i) const {
if (tesseract_ == nullptr || i >= NumDawgs()) return nullptr;
return tesseract_->getDict().GetDawg(i);
}
/** Return the number of dawgs loaded into tesseract_ object. */
int TessBaseAPI::NumDawgs() const {
return tesseract_ == nullptr ? 0 : tesseract_->getDict().NumDawgs();
}
/** Escape a char string - remove <>&"' with HTML codes. */
STRING HOcrEscape(const char* text) {
STRING ret;
const char *ptr;
for (ptr = text; *ptr; ptr++) {
switch (*ptr) {
case '<': ret += "&lt;"; break;
case '>': ret += "&gt;"; break;
case '&': ret += "&amp;"; break;
case '"': ret += "&quot;"; break;
case '\'': ret += "&#39;"; break;
default: ret += *ptr;
}
}
return ret;
}
#ifndef DISABLED_LEGACY_ENGINE
// ____________________________________________________________________________
// Ocropus add-ons.
/** Find lines from the image making the BLOCK_LIST. */
BLOCK_LIST* TessBaseAPI::FindLinesCreateBlockList() {
ASSERT_HOST(FindLines() == 0);
BLOCK_LIST* result = block_list_;
block_list_ = nullptr;
return result;
}
/**
* Delete a block list.
* This is to keep BLOCK_LIST pointer opaque
* and let go of including the other headers.
*/
void TessBaseAPI::DeleteBlockList(BLOCK_LIST *block_list) {
delete block_list;
}
ROW *TessBaseAPI::MakeTessOCRRow(float baseline,
float xheight,
float descender,
float ascender) {
int32_t xstarts[] = {-32000};
double quad_coeffs[] = {0, 0, baseline};
return new ROW(1,
xstarts,
quad_coeffs,
xheight,
ascender - (baseline + xheight),
descender - baseline,
0,
0);
}
/** Creates a TBLOB* from the whole pix. */
TBLOB *TessBaseAPI::MakeTBLOB(Pix *pix) {
int width = pixGetWidth(pix);
int height = pixGetHeight(pix);
BLOCK block("a character", true, 0, 0, 0, 0, width, height);
// Create C_BLOBs from the page
extract_edges(pix, &block);
// Merge all C_BLOBs
C_BLOB_LIST *list = block.blob_list();
C_BLOB_IT c_blob_it(list);
if (c_blob_it.empty())
return nullptr;
// Move all the outlines to the first blob.
C_OUTLINE_IT ol_it(c_blob_it.data()->out_list());
for (c_blob_it.forward();
!c_blob_it.at_first();
c_blob_it.forward()) {
C_BLOB *c_blob = c_blob_it.data();
ol_it.add_list_after(c_blob->out_list());
}
// Convert the first blob to the output TBLOB.
return TBLOB::PolygonalCopy(false, c_blob_it.data());
}
/**
* This method baseline normalizes a TBLOB in-place. The input row is used
* for normalization. The denorm is an optional parameter in which the
* normalization-antidote is returned.
*/
void TessBaseAPI::NormalizeTBLOB(TBLOB *tblob, ROW *row, bool numeric_mode) {
TBOX box = tblob->bounding_box();
float x_center = (box.left() + box.right()) / 2.0f;
float baseline = row->base_line(x_center);
float scale = kBlnXHeight / row->x_height();
tblob->Normalize(nullptr, nullptr, nullptr, x_center, baseline, scale, scale,
0.0f, static_cast<float>(kBlnBaselineOffset), false, nullptr);
}
/**
* Return a TBLOB * from the whole pix.
* To be freed later with delete.
*/
static TBLOB *make_tesseract_blob(float baseline, float xheight,
float descender, float ascender,
bool numeric_mode, Pix* pix) {
TBLOB *tblob = TessBaseAPI::MakeTBLOB(pix);
// Normalize TBLOB
ROW *row =
TessBaseAPI::MakeTessOCRRow(baseline, xheight, descender, ascender);
TessBaseAPI::NormalizeTBLOB(tblob, row, numeric_mode);
delete row;
return tblob;
}
/**
* Adapt to recognize the current image as the given character.
* The image must be preloaded into pix_binary_ and be just an image
* of a single character.
*/
void TessBaseAPI::AdaptToCharacter(const char *unichar_repr,
int length,
float baseline,
float xheight,
float descender,
float ascender) {
UNICHAR_ID id = tesseract_->unicharset.unichar_to_id(unichar_repr, length);
TBLOB *blob = make_tesseract_blob(baseline, xheight, descender, ascender,
tesseract_->classify_bln_numeric_mode,
tesseract_->pix_binary());
float threshold;
float best_rating = -100;
// Classify to get a raw choice.
BLOB_CHOICE_LIST choices;
tesseract_->AdaptiveClassifier(blob, &choices);
BLOB_CHOICE_IT choice_it;
choice_it.set_to_list(&choices);
for (choice_it.mark_cycle_pt(); !choice_it.cycled_list();
choice_it.forward()) {
if (choice_it.data()->rating() > best_rating) {
best_rating = choice_it.data()->rating();
}
}
threshold = tesseract_->matcher_good_threshold;
if (blob->outlines)
tesseract_->AdaptToChar(blob, id, kUnknownFontinfoId, threshold,
tesseract_->AdaptedTemplates);
delete blob;
}
PAGE_RES* TessBaseAPI::RecognitionPass1(BLOCK_LIST* block_list) {
auto *page_res = new PAGE_RES(false, block_list,
&(tesseract_->prev_word_best_choice_));
tesseract_->recog_all_words(page_res, nullptr, nullptr, nullptr, 1);
return page_res;
}
PAGE_RES* TessBaseAPI::RecognitionPass2(BLOCK_LIST* block_list,
PAGE_RES* pass1_result) {
if (!pass1_result)
pass1_result = new PAGE_RES(false, block_list,
&(tesseract_->prev_word_best_choice_));
tesseract_->recog_all_words(pass1_result, nullptr, nullptr, nullptr, 2);
return pass1_result;
}
struct TESS_CHAR : ELIST_LINK {
char *unicode_repr;
int length; // of unicode_repr
float cost;
TBOX box;
TESS_CHAR(float _cost, const char *repr, int len = -1) : cost(_cost) {
length = (len == -1 ? strlen(repr) : len);
unicode_repr = new char[length + 1];
strncpy(unicode_repr, repr, length);
}
TESS_CHAR()
: unicode_repr(nullptr),
length(0),
cost(0.0f)
{ // Satisfies ELISTIZE.
}
~TESS_CHAR() {
delete [] unicode_repr;
}
};
ELISTIZEH(TESS_CHAR)
ELISTIZE(TESS_CHAR)
static void add_space(TESS_CHAR_IT* it) {
auto *t = new TESS_CHAR(0, " ");
it->add_after_then_move(t);
}
static float rating_to_cost(float rating) {
rating = 100 + rating;
// cuddled that to save from coverage profiler
// (I have never seen ratings worse than -100,
// but the check won't hurt)
if (rating < 0) rating = 0;
return rating;
}
/**
* Extract the OCR results, costs (penalty points for uncertainty),
* and the bounding boxes of the characters.
*/
static void extract_result(TESS_CHAR_IT* out,
PAGE_RES* page_res) {
PAGE_RES_IT page_res_it(page_res);
int word_count = 0;
while (page_res_it.word() != nullptr) {
WERD_RES *word = page_res_it.word();
const char *str = word->best_choice->unichar_string().string();
const char *len = word->best_choice->unichar_lengths().string();
TBOX real_rect = word->word->bounding_box();
if (word_count)
add_space(out);
int n = strlen(len);
for (int i = 0; i < n; i++) {
auto *tc = new TESS_CHAR(rating_to_cost(word->best_choice->rating()),
str, *len);
tc->box = real_rect.intersection(word->box_word->BlobBox(i));
out->add_after_then_move(tc);
str += *len;
len++;
}
page_res_it.forward();
word_count++;
}
}
/**
* Extract the OCR results, costs (penalty points for uncertainty),
* and the bounding boxes of the characters.
*/
int TessBaseAPI::TesseractExtractResult(char** text,
int** lengths,
float** costs,
int** x0,
int** y0,
int** x1,
int** y1,
PAGE_RES* page_res) {
TESS_CHAR_LIST tess_chars;
TESS_CHAR_IT tess_chars_it(&tess_chars);
extract_result(&tess_chars_it, page_res);
tess_chars_it.move_to_first();
int n = tess_chars.length();
int text_len = 0;
*lengths = new int[n];
*costs = new float[n];
*x0 = new int[n];
*y0 = new int[n];
*x1 = new int[n];
*y1 = new int[n];
int i = 0;
for (tess_chars_it.mark_cycle_pt();
!tess_chars_it.cycled_list();
tess_chars_it.forward(), i++) {
TESS_CHAR *tc = tess_chars_it.data();
text_len += (*lengths)[i] = tc->length;
(*costs)[i] = tc->cost;
(*x0)[i] = tc->box.left();
(*y0)[i] = tc->box.bottom();
(*x1)[i] = tc->box.right();
(*y1)[i] = tc->box.top();
}
char *p = *text = new char[text_len];
tess_chars_it.move_to_first();
for (tess_chars_it.mark_cycle_pt();
!tess_chars_it.cycled_list();
tess_chars_it.forward()) {
TESS_CHAR *tc = tess_chars_it.data();
strncpy(p, tc->unicode_repr, tc->length);
p += tc->length;
}
return n;
}
/** This method returns the features associated with the input blob. */
// The resulting features are returned in int_features, which must be
// of size MAX_NUM_INT_FEATURES. The number of features is returned in
// num_features (or 0 if there was a failure).
// On return feature_outline_index is filled with an index of the outline
// corresponding to each feature in int_features.
// TODO(rays) Fix the caller to out outline_counts instead.
void TessBaseAPI::GetFeaturesForBlob(TBLOB* blob,
INT_FEATURE_STRUCT* int_features,
int* num_features,
int* feature_outline_index) {
GenericVector<int> outline_counts;
GenericVector<INT_FEATURE_STRUCT> bl_features;
GenericVector<INT_FEATURE_STRUCT> cn_features;
INT_FX_RESULT_STRUCT fx_info;
tesseract_->ExtractFeatures(*blob, false, &bl_features,
&cn_features, &fx_info, &outline_counts);
if (cn_features.empty() || cn_features.size() > MAX_NUM_INT_FEATURES) {
*num_features = 0;
return; // Feature extraction failed.
}
*num_features = cn_features.size();
memcpy(int_features, &cn_features[0], *num_features * sizeof(cn_features[0]));
// TODO(rays) Pass outline_counts back and simplify the calling code.
if (feature_outline_index != nullptr) {
int f = 0;
for (int i = 0; i < outline_counts.size(); ++i) {
while (f < outline_counts[i])
feature_outline_index[f++] = i;
}
}
}
// This method returns the row to which a box of specified dimensions would
// belong. If no good match is found, it returns nullptr.
ROW* TessBaseAPI::FindRowForBox(BLOCK_LIST* blocks,
int left, int top, int right, int bottom) {
TBOX box(left, bottom, right, top);
BLOCK_IT b_it(blocks);
for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
BLOCK* block = b_it.data();
if (!box.major_overlap(block->pdblk.bounding_box()))
continue;
ROW_IT r_it(block->row_list());
for (r_it.mark_cycle_pt(); !r_it.cycled_list(); r_it.forward()) {
ROW* row = r_it.data();
if (!box.major_overlap(row->bounding_box()))
continue;
WERD_IT w_it(row->word_list());
for (w_it.mark_cycle_pt(); !w_it.cycled_list(); w_it.forward()) {
WERD* word = w_it.data();
if (box.major_overlap(word->bounding_box()))
return row;
}
}
}
return nullptr;
}
/** Method to run adaptive classifier on a blob. */
void TessBaseAPI::RunAdaptiveClassifier(TBLOB* blob,
int num_max_matches,
int* unichar_ids,
float* ratings,
int* num_matches_returned) {
auto* choices = new BLOB_CHOICE_LIST;
tesseract_->AdaptiveClassifier(blob, choices);
BLOB_CHOICE_IT choices_it(choices);
int& index = *num_matches_returned;
index = 0;
for (choices_it.mark_cycle_pt();
!choices_it.cycled_list() && index < num_max_matches;
choices_it.forward()) {
BLOB_CHOICE* choice = choices_it.data();
unichar_ids[index] = choice->unichar_id();
ratings[index] = choice->rating();
++index;
}
*num_matches_returned = index;
delete choices;
}
#endif // ndef DISABLED_LEGACY_ENGINE
} // namespace tesseract.
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