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tesseract/src/api/baseapi.cpp
Stefan Weil 9e6e3a0232 Fix memory leak for PNG images 
Commit 5fe1390748 used an implementation
which created a new Pix object. That object was never destroyed.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
2019-01-23 20:05:10 +01:00

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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 <clocale> // for LC_ALL, LC_CTYPE, LC_NUMERIC
#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 <memory> // for std::unique_ptr
#include <set> // for std::pair
#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, FALSE, TRUE
#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 "host.h" // for BOOL8
#include "imageio.h" // for IFF_TIFF_G4, IFF_TIFF, IFF_TIFF_G3
#include "intfx.h" // for INT_FX_RESULT_STRUCT
#include "mutableiterator.h" // for MutableIterator
#include "normalis.h" // for kBlnBaselineOffset, kBlnXHeight
#include "ocrclass.h" // for ETEXT_DESC
#include "openclwrapper.h" // for PERF_COUNT_END, PERF_COUNT_START, PERF...
#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 STRING* s1 = static_cast<const STRING*>(p1);
const STRING* 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) {
const char *locale;
locale = std::setlocale(LC_ALL, nullptr);
ASSERT_HOST(!strcmp(locale, "C"));
locale = std::setlocale(LC_CTYPE, nullptr);
ASSERT_HOST(!strcmp(locale, "C"));
locale = std::setlocale(LC_NUMERIC, nullptr);
ASSERT_HOST(!strcmp(locale, "C"));
}
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 {
IntParam *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 {
BoolParam *p = ParamUtils::FindParam<BoolParam>(
name, GlobalParams()->bool_params, tesseract_->params()->bool_params);
if (p == nullptr) return false;
*value = (BOOL8)(*p);
return true;
}
const char *TessBaseAPI::GetStringVariable(const char *name) const {
StringParam *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 {
DoubleParam *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 (no ending /) 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) {
PERF_COUNT_START("TessBaseAPI::Init")
// 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;
}
// PERF_COUNT_SUB("delete tesseract_")
#ifdef USE_OPENCL
OpenclDevice od;
od.InitEnv();
#endif
PERF_COUNT_SUB("OD::InitEnv()")
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;
}
}
PERF_COUNT_SUB("update tesseract_")
// 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
// PERF_COUNT_SUB("update last_oem_requested_")
// For same language and datapath, just reset the adaptive classifier.
if (reset_classifier) {
tesseract_->ResetAdaptiveClassifier();
PERF_COUNT_SUB("tesseract_->ResetAdaptiveClassifier()")
}
#endif // ndef DISABLED_LEGACY_ENGINE
PERF_COUNT_END
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);
PageIterator *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) {
PERF_COUNT_START("ProcessPages")
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;
}
PERF_COUNT_END
return true;
}
bool TessBaseAPI::ProcessPage(Pix* pix, int page_index, const char* filename,
const char* retry_config, int timeout_millisec,
TessResultRenderer* renderer) {
PERF_COUNT_START("ProcessPage")
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);
}
PERF_COUNT_END
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);
const int kOsdBufsize = 255;
char* osd_buf = new char[kOsdBufsize];
snprintf(osd_buf, kOsdBufsize,
"Page number: %d\n"
"Orientation in degrees: %d\n"
"Rotate: %d\n"
"Orientation confidence: %.2f\n"
"Script: %s\n"
"Script confidence: %.2f\n",
page_number, orient_deg, rotate, orient_conf, script_name,
script_conf);
return osd_buf;
}
#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);
}
PageSegMode 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) {
PAGE_RES *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) {
TESS_CHAR *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++) {
TESS_CHAR *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) {
BLOB_CHOICE_LIST* 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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