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baseapi.cpp
2998 lines (2766 loc) · 103 KB
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baseapi.cpp
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/**********************************************************************
* File: baseapi.cpp
* Description: Simple API for calling tesseract.
* Author: Ray Smith
* Created: Fri Oct 06 15:35:01 PDT 2006
*
* (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
}
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.
*/
#ifdef USE_OPENCL
#if USE_DEVICE_SELECTION
#include "opencl_device_selection.h"
#endif
#endif
size_t TessBaseAPI::getOpenCLDevice(void **data) {
#ifdef USE_OPENCL
#if USE_DEVICE_SELECTION
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
#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 vector of STRINGs.
*/
void TessBaseAPI::GetAvailableLanguagesAsVector(
GenericVector<STRING>* langs) const {
langs->clear();
if (tesseract_ != nullptr) {
addAvailableLanguages(tesseract_->datadir, "", langs);
}
}
//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);
pix = pixCopy(nullptr, 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++) {