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///////////////////////////////////////////////////////////////////////
// File: baseapi.h
// 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.
//
///////////////////////////////////////////////////////////////////////
#ifndef TESSERACT_API_BASEAPI_H_
#define TESSERACT_API_BASEAPI_H_
#include <cstdio>
// To avoid collision with other typenames include the ABSOLUTE MINIMUM
// complexity of includes here. Use forward declarations wherever possible
// and hide includes of complex types in baseapi.cpp.
#include "apitypes.h"
#include "pageiterator.h"
#include "platform.h"
#include "publictypes.h"
#include "resultiterator.h"
#include "serialis.h"
#include "tess_version.h"
#include "tesscallback.h"
#include "thresholder.h"
#include "unichar.h"
template <typename T> class GenericVector;
class PAGE_RES;
class PAGE_RES_IT;
class ParagraphModel;
struct BlamerBundle;
class BLOCK_LIST;
class DENORM;
class MATRIX;
class ROW;
class STRING;
class WERD;
struct Pix;
struct Box;
struct Pixa;
struct Boxa;
class ETEXT_DESC;
struct OSResults;
class TBOX;
class UNICHARSET;
class WERD_CHOICE_LIST;
struct INT_FEATURE_STRUCT;
using INT_FEATURE = INT_FEATURE_STRUCT *;
struct TBLOB;
namespace tesseract {
class Dawg;
class Dict;
class EquationDetect;
class PageIterator;
class LTRResultIterator;
class ResultIterator;
class MutableIterator;
class TessResultRenderer;
class Tesseract;
class Trie;
class Wordrec;
using DictFunc = int (Dict::*)(void *, const UNICHARSET &, UNICHAR_ID, bool) const;
using ProbabilityInContextFunc = double (Dict::*)(const char *, const char *, int, const char *, int);
using ParamsModelClassifyFunc = float (Dict::*)(const char *, void *);
using FillLatticeFunc = void (Wordrec::*)(const MATRIX &, const WERD_CHOICE_LIST &, const UNICHARSET &, BlamerBundle *);
typedef TessCallback4<const UNICHARSET &, int, PageIterator *, Pix *>
TruthCallback;
/**
* Base class for all tesseract APIs.
* Specific classes can add ability to work on different inputs or produce
* different outputs.
* This class is mostly an interface layer on top of the Tesseract instance
* class to hide the data types so that users of this class don't have to
* include any other Tesseract headers.
*/
class TESS_API TessBaseAPI {
public:
TessBaseAPI();
virtual ~TessBaseAPI();
/**
* Returns the version identifier as a static string. Do not delete.
*/
static const char* 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.
*/
static size_t getOpenCLDevice(void **device);
/**
* Writes the thresholded image to stderr as a PBM file on receipt of a
* SIGSEGV, SIGFPE, or SIGBUS signal. (Linux/Unix only).
*/
static void CatchSignals();
/**
* Set the name of the input file. Needed for training and
* reading a UNLV zone file, and for searchable PDF output.
*/
void SetInputName(const char* name);
/**
* These functions are required for searchable PDF output.
* We need our hands on the input file so that we can include
* it in the PDF without transcoding. If that is not possible,
* we need the original image. Finally, resolution metadata
* is stored in the PDF so we need that as well.
*/
const char* GetInputName();
// Takes ownership of the input pix.
void SetInputImage(Pix *pix);
Pix* GetInputImage();
int GetSourceYResolution();
const char* GetDatapath();
/** Set the name of the bonus output files. Needed only for debugging. */
void SetOutputName(const char* name);
/**
* Set the value of an internal "parameter."
* Supply the name of the parameter and the value as a string, just as
* you would in a config file.
* Returns false if the name lookup failed.
* Eg SetVariable("tessedit_char_blacklist", "xyz"); to ignore x, y and z.
* Or SetVariable("classify_bln_numeric_mode", "1"); to set numeric-only mode.
* SetVariable may be used before Init, but settings will revert to
* defaults on End().
*
* Note: Must be called after Init(). Only works for non-init variables
* (init variables should be passed to Init()).
*/
bool SetVariable(const char* name, const char* value);
bool SetDebugVariable(const char* name, const char* value);
/**
* Returns true if the parameter was found among Tesseract parameters.
* Fills in value with the value of the parameter.
*/
bool GetIntVariable(const char *name, int *value) const;
bool GetBoolVariable(const char *name, bool *value) const;
bool GetDoubleVariable(const char *name, double *value) const;
/**
* Returns the pointer to the string that represents the value of the
* parameter if it was found among Tesseract parameters.
*/
const char *GetStringVariable(const char *name) const;
/**
* Print Tesseract parameters to the given file.
*/
void PrintVariables(FILE *fp) const;
/**
* Get value of named variable as a string, if it exists.
*/
bool GetVariableAsString(const char *name, STRING *val);
/**
* Instances are now mostly thread-safe and totally independent,
* but some global parameters remain. Basically it is safe to use multiple
* TessBaseAPIs in different threads in parallel, UNLESS:
* you use SetVariable on some of the Params in classify and textord.
* If you do, then the effect will be to change it for all your instances.
*
* Start tesseract. Returns zero on success and -1 on failure.
* NOTE that the only members that may be called before Init are those
* listed above here in the class definition.
*
* The datapath must be the name of the tessdata directory.
* The language is (usually) an ISO 639-3 string or nullptr will default to eng.
* It is entirely safe (and eventually will be efficient too) to call
* Init multiple times on the same instance to change language, or just
* to reset the classifier.
* The language may be a string of the form [~]<lang>[+[~]<lang>]* indicating
* that multiple languages are to be loaded. Eg hin+eng will load Hindi and
* English. Languages may specify internally that they want to be loaded
* with one or more other languages, so the ~ sign is available to override
* that. Eg if hin were set to load eng by default, then hin+~eng would force
* loading only hin. The number of loaded languages is limited only by
* memory, with the caveat that loading additional languages will impact
* both speed and accuracy, as there is more work to do to decide on the
* applicable language, and there is more chance of hallucinating incorrect
* words.
* WARNING: On changing languages, all Tesseract parameters are reset
* back to their default values. (Which may vary between languages.)
* If you have a rare need to set a Variable that controls
* initialization for a second call to Init you should explicitly
* call End() and then use SetVariable before Init. This is only a very
* rare use case, since there are very few uses that require any parameters
* to be set before Init.
*
* If set_only_non_debug_params is true, only params that do not contain
* "debug" in the name will be set.
*/
int Init(const char* datapath, const char* language, OcrEngineMode mode,
char **configs, int configs_size,
const GenericVector<STRING> *vars_vec,
const GenericVector<STRING> *vars_values,
bool set_only_non_debug_params);
int Init(const char* datapath, const char* language, OcrEngineMode oem) {
return Init(datapath, language, oem, nullptr, 0, nullptr, nullptr, false);
}
int Init(const char* datapath, const char* language) {
return Init(datapath, language, OEM_DEFAULT, nullptr, 0, nullptr, nullptr, false);
}
// In-memory version reads the traineddata file directly from the given
// data[data_size] array, and/or reads data via a FileReader.
int Init(const char* data, int data_size, const char* language,
OcrEngineMode mode, char** configs, int configs_size,
const GenericVector<STRING>* vars_vec,
const GenericVector<STRING>* vars_values,
bool set_only_non_debug_params, FileReader reader);
/**
* 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* GetInitLanguagesAsString() const;
/**
* 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 GetLoadedLanguagesAsVector(GenericVector<STRING>* langs) const;
/**
* Returns the available languages in the sorted vector of STRINGs.
*/
void GetAvailableLanguagesAsVector(GenericVector<STRING>* langs) const;
/**
* 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 InitLangMod(const char* datapath, const char* language);
/**
* Init only for page layout analysis. Use only for calls to SetImage and
* AnalysePage. Calls that attempt recognition will generate an error.
*/
void InitForAnalysePage();
/**
* Read a "config" file containing a set of param, value pairs.
* Searches the standard places: tessdata/configs, tessdata/tessconfigs
* and also accepts a relative or absolute path name.
* Note: only non-init params will be set (init params are set by Init()).
*/
void ReadConfigFile(const char* filename);
/** Same as above, but only set debug params from the given config file. */
void ReadDebugConfigFile(const char* filename);
/**
* Set the current page segmentation mode. Defaults to PSM_SINGLE_BLOCK.
* The mode is stored as an IntParam so it can also be modified by
* ReadConfigFile or SetVariable("tessedit_pageseg_mode", mode as string).
*/
void SetPageSegMode(PageSegMode mode);
/** Return the current page segmentation mode. */
PageSegMode GetPageSegMode() const;
/**
* 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
* 1 represents 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.
*
* Note that TesseractRect is the simplified convenience interface.
* For advanced uses, use SetImage, (optionally) SetRectangle, Recognize,
* and one or more of the Get*Text functions below.
*/
char* TesseractRect(const unsigned char* imagedata,
int bytes_per_pixel, int bytes_per_line,
int left, int top, int width, int height);
/**
* Call between pages or documents etc to free up memory and forget
* adaptive data.
*/
void ClearAdaptiveClassifier();
/**
* @defgroup AdvancedAPI Advanced API
* The following methods break TesseractRect into pieces, so you can
* get hold of the thresholded image, get the text in different formats,
* get bounding boxes, confidences etc.
*/
/* @{ */
/**
* 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 SetImage(const unsigned char* imagedata, int width, int height,
int bytes_per_pixel, int bytes_per_line);
/**
* 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 SetImage(Pix* pix);
/**
* Set the resolution of the source image in pixels per inch so font size
* information can be calculated in results. Call this after SetImage().
*/
void SetSourceResolution(int ppi);
/**
* 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 SetRectangle(int left, int top, int width, int height);
/**
* In extreme cases only, usually with a subclass of Thresholder, it
* is possible to provide a different Thresholder. The Thresholder may
* be preloaded with an image, settings etc, or they may be set after.
* Note that Tesseract takes ownership of the Thresholder and will
* delete it when it it is replaced or the API is destructed.
*/
void SetThresholder(ImageThresholder* thresholder) {
delete thresholder_;
thresholder_ = thresholder;
ClearResults();
}
/**
* Get a copy of the internal thresholded image from Tesseract.
* Caller takes ownership of the Pix and must pixDestroy it.
* May be called any time after SetImage, or after TesseractRect.
*/
Pix* GetThresholdedImage();
/**
* 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* GetRegions(Pixa** pixa);
/**
* Get the textlines as a leptonica-style
* Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
* If raw_image is true, then extract from the original image instead of the
* thresholded image and pad by raw_padding pixels.
* 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* GetTextlines(bool raw_image, int raw_padding,
Pixa** pixa, int** blockids, int** paraids);
/*
Helper method to extract from the thresholded image. (most common usage)
*/
Boxa* GetTextlines(Pixa** pixa, int** blockids) {
return GetTextlines(false, 0, pixa, blockids, nullptr);
}
/**
* 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* GetStrips(Pixa** pixa, int** blockids);
/**
* Get the words as a leptonica-style
* Boxa, Pixa pair, in reading order.
* Can be called before or after Recognize.
*/
Boxa* GetWords(Pixa** pixa);
/**
* 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.
* Note: the caller is responsible for calling boxaDestroy()
* on the returned Boxa array and pixaDestroy() on cc array.
*/
Boxa* GetConnectedComponents(Pixa** cc);
/**
* 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 blockids is not nullptr, the paragraph-id of each component with its block
* is also returned as an array of one element per component. delete [] after
* use.
* If raw_image is true, then portions of the original image are extracted
* instead of the thresholded image and padded with raw_padding.
* If text_only is true, then only text components are returned.
*/
Boxa* GetComponentImages(PageIteratorLevel level,
bool text_only, bool raw_image,
int raw_padding,
Pixa** pixa, int** blockids, int** paraids);
// Helper function to get binary images with no padding (most common usage).
Boxa* GetComponentImages(const PageIteratorLevel level,
const bool text_only,
Pixa** pixa, int** blockids) {
return GetComponentImages(level, text_only, false, 0, pixa, blockids, nullptr);
}
/**
* Returns the scale factor of the thresholded image that would be returned by
* GetThresholdedImage() and the various GetX() methods that call
* GetComponentImages().
* Returns 0 if no thresholder has been set.
*/
int GetThresholdedImageScaleFactor() const;
/**
* 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* AnalyseLayout();
PageIterator* AnalyseLayout(bool merge_similar_words);
/**
* Recognize the image from SetAndThresholdImage, generating Tesseract
* internal structures. Returns 0 on success.
* Optional. The Get*Text functions below will call Recognize if needed.
* After Recognize, the output is kept internally until the next SetImage.
*/
int Recognize(ETEXT_DESC* monitor);
/**
* Methods to retrieve information after SetAndThresholdImage(),
* Recognize() or TesseractRect(). (Recognize is called implicitly if needed.)
*/
#ifndef DISABLED_LEGACY_ENGINE
/** Variant on Recognize used for testing chopper. */
int RecognizeForChopTest(ETEXT_DESC* monitor);
#endif
/**
* Turns images into symbolic text.
*
* filename can point to a single image, a multi-page TIFF,
* or a plain text list of image filenames.
*
* retry_config is useful for debugging. If not nullptr, you can fall
* back to an alternate configuration if a page fails for some
* reason.
*
* timeout_millisec terminates processing if any single page
* takes too long. Set to 0 for unlimited time.
*
* renderer is responible for creating the output. For example,
* use the TessTextRenderer if you want plaintext output, or
* the TessPDFRender to produce searchable PDF.
*
* If tessedit_page_number is non-negative, will only process that
* single page. Works for multi-page tiff file, or filelist.
*
* Returns true if successful, false on error.
*/
bool ProcessPages(const char* filename, const char* retry_config,
int timeout_millisec, TessResultRenderer* renderer);
// Does the real work of ProcessPages.
bool ProcessPagesInternal(const char* filename, const char* retry_config,
int timeout_millisec, TessResultRenderer* renderer);
/**
* Turn a single image into symbolic text.
*
* The pix is the image processed. filename and page_index are
* metadata used by side-effect processes, such as reading a box
* file or formatting as hOCR.
*
* See ProcessPages for desciptions of other parameters.
*/
bool ProcessPage(Pix* pix, int page_index, const char* filename,
const char* retry_config, int timeout_millisec,
TessResultRenderer* renderer);
/**
* 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* GetIterator();
/**
* 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* GetMutableIterator();
/**
* The recognized text is returned as a char* which is coded
* as UTF8 and must be freed with the delete [] operator.
*/
char* GetUTF8Text();
/**
* Make a HTML-formatted string with hOCR markup from the internal
* data structures.
* page_number is 0-based but will appear in the output as 1-based.
* monitor can be used to
* cancel the recognition
* receive progress callbacks
* Returned string must be freed with the delete [] operator.
*/
char* GetHOCRText(ETEXT_DESC* monitor, int page_number);
/**
* Make a HTML-formatted string with hOCR markup 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* GetHOCRText(int page_number);
/**
* Make an XML-formatted string with Alto markup from the internal
* data structures.
*/
char* GetAltoText(ETEXT_DESC* monitor, int page_number);
/**
* Make an XML-formatted string with Alto markup from the internal
* data structures.
*/
char* GetAltoText(int page_number);
/**
* 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* GetTSVText(int page_number);
/**
* Make a box file for LSTM training from the internal data structures.
* Constructs coordinates in the original image - not just the rectangle.
* page_number is a 0-based page index that will appear in the box file.
* Returned string must be freed with the delete [] operator.
*/
char* GetLSTMBoxText(int page_number);
/**
* The recognized text is returned as a char* which is coded in the same
* format as a box file used in training.
* Constructs coordinates in the original image - not just the rectangle.
* page_number is a 0-based page index that will appear in the box file.
* Returned string must be freed with the delete [] operator.
*/
char* GetBoxText(int page_number);
/**
* The recognized text is returned as a char* which is coded in the same
* format as a WordStr box file used in training.
* page_number is a 0-based page index that will appear in the box file.
* Returned string must be freed with the delete [] operator.
*/
char* GetWordStrBoxText(int page_number);
/**
* 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* GetUNLVText();
/**
* 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 DetectOrientationScript(int* orient_deg, float* orient_conf,
const char** script_name, float* script_conf);
/**
* 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* GetOsdText(int page_number);
/** Returns the (average) confidence value between 0 and 100. */
int MeanTextConf();
/**
* Returns all word confidences (between 0 and 100) in an array, terminated
* by -1. The calling function must delete [] after use.
* The number of confidences should correspond to the number of space-
* delimited words in GetUTF8Text.
*/
int* AllWordConfidences();
#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 AdaptToWordStr(PageSegMode mode, const char* wordstr);
#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 Clear();
/**
* 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 End();
/**
* 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.
**/
static void ClearPersistentCache();
/**
* Check whether a word is valid according to Tesseract's language model
* @return 0 if the word is invalid, non-zero if valid.
* @warning temporary! This function will be removed from here and placed
* in a separate API at some future time.
*/
int IsValidWord(const char *word);
// Returns true if utf8_character is defined in the UniCharset.
bool IsValidCharacter(const char *utf8_character);
bool GetTextDirection(int* out_offset, float* out_slope);
/** Sets Dict::letter_is_okay_ function to point to the given function. */
void SetDictFunc(DictFunc f);
/** Sets Dict::probability_in_context_ function to point to the given
* function.
*/
void SetProbabilityInContextFunc(ProbabilityInContextFunc f);
/**
* Estimates the Orientation And Script of the image.
* @return true if the image was processed successfully.
*/
bool DetectOS(OSResults*);
/**
* Return text orientation of each block as determined by an earlier run
* of layout analysis.
*/
void GetBlockTextOrientations(int** block_orientation,
bool** vertical_writing);
#ifndef DISABLED_LEGACY_ENGINE
/** Sets Wordrec::fill_lattice_ function to point to the given function. */
void SetFillLatticeFunc(FillLatticeFunc f);
/** Find lines from the image making the BLOCK_LIST. */
BLOCK_LIST* FindLinesCreateBlockList();
/**
* Delete a block list.
* This is to keep BLOCK_LIST pointer opaque
* and let go of including the other headers.
*/
static void DeleteBlockList(BLOCK_LIST* block_list);
/** Returns a ROW object created from the input row specification. */
static ROW *MakeTessOCRRow(float baseline, float xheight,
float descender, float ascender);
/** Returns a TBLOB corresponding to the entire input image. */
static TBLOB *MakeTBLOB(Pix *pix);
/**
* 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.
*/
static void NormalizeTBLOB(TBLOB *tblob, ROW *row, bool numeric_mode);
/** This method returns the features associated with the input image. */
void GetFeaturesForBlob(TBLOB* blob, INT_FEATURE_STRUCT* int_features,
int* num_features, int* feature_outline_index);
/**
* This method returns the row to which a box of specified dimensions would
* belong. If no good match is found, it returns nullptr.
*/
static ROW* FindRowForBox(BLOCK_LIST* blocks, int left, int top,
int right, int bottom);
/**
* Method to run adaptive classifier on a blob.
* It returns at max num_max_matches results.
*/
void RunAdaptiveClassifier(TBLOB* blob,
int num_max_matches,
int* unichar_ids,
float* ratings,
int* num_matches_returned);
#endif // ndef DISABLED_LEGACY_ENGINE
/** This method returns the string form of the specified unichar. */
const char* GetUnichar(int unichar_id);
/** Return the pointer to the i-th dawg loaded into tesseract_ object. */
const Dawg *GetDawg(int i) const;
/** Return the number of dawgs loaded into tesseract_ object. */
int NumDawgs() const;
Tesseract* tesseract() const { return tesseract_; }
OcrEngineMode oem() const { return last_oem_requested_; }
void InitTruthCallback(TruthCallback *cb) { truth_cb_ = cb; }
void set_min_orientation_margin(double margin);
/* @} */
protected:
/** Common code for setting the image. Returns true if Init has been called. */
TESS_LOCAL bool InternalSetImage();
/**
* Run the thresholder to make the thresholded image. If pix is not nullptr,
* the source is thresholded to pix instead of the internal IMAGE.
*/
TESS_LOCAL virtual bool Threshold(Pix** pix);
/**
* Find lines from the image making the BLOCK_LIST.
* @return 0 on success.
*/
TESS_LOCAL int FindLines();
/** Delete the pageres and block list ready for a new page. */
void ClearResults();
/**
* Return an LTR Result Iterator -- used only for training, as we really want
* to ignore all BiDi smarts at that point.
* delete once you're done with it.
*/
TESS_LOCAL LTRResultIterator* GetLTRIterator();
/**
* Return the length of the output text string, as UTF8, assuming
* one newline per line and one per block, with a terminator,
* and assuming a single character reject marker for each rejected character.
* Also return the number of recognized blobs in blob_count.
*/
TESS_LOCAL int TextLength(int* blob_count);
//// paragraphs.cpp ////////////////////////////////////////////////////
TESS_LOCAL void DetectParagraphs(bool after_text_recognition);
#ifndef DISABLED_LEGACY_ENGINE
/** @defgroup ocropusAddOns ocropus add-ons */
/* @{ */
/**
* Adapt to recognize the current image as the given character.
* The image must be preloaded and be just an image of a single character.
*/
TESS_LOCAL void AdaptToCharacter(const char *unichar_repr,
int length,
float baseline,
float xheight,
float descender,
float ascender);
/** Recognize text doing one pass only, using settings for a given pass. */
TESS_LOCAL PAGE_RES* RecognitionPass1(BLOCK_LIST* block_list);
TESS_LOCAL PAGE_RES* RecognitionPass2(BLOCK_LIST* block_list,
PAGE_RES* pass1_result);
/**
* Extract the OCR results, costs (penalty points for uncertainty),
* and the bounding boxes of the characters.
*/
TESS_LOCAL static int TesseractExtractResult(char** text,
int** lengths,
float** costs,
int** x0,
int** y0,
int** x1,
int** y1,
PAGE_RES* page_res);
TESS_LOCAL const PAGE_RES* GetPageRes() const { return page_res_; }
/* @} */
#endif // ndef DISABLED_LEGACY_ENGINE
protected:
Tesseract* tesseract_; ///< The underlying data object.
Tesseract* osd_tesseract_; ///< For orientation & script detection.
EquationDetect* equ_detect_; ///<The equation detector.
FileReader reader_; ///< Reads files from any filesystem.
ImageThresholder* thresholder_; ///< Image thresholding module.
GenericVector<ParagraphModel *>* paragraph_models_;
BLOCK_LIST* block_list_; ///< The page layout.
PAGE_RES* page_res_; ///< The page-level data.
STRING* input_file_; ///< Name used by training code.
STRING* output_file_; ///< Name used by debug code.
STRING* datapath_; ///< Current location of tessdata.
STRING* language_; ///< Last initialized language.
OcrEngineMode last_oem_requested_; ///< Last ocr language mode requested.
bool recognition_done_; ///< page_res_ contains recognition data.
TruthCallback *truth_cb_; /// fxn for setting truth_* in WERD_RES
/**
* @defgroup ThresholderParams Thresholder Parameters
* Parameters saved from the Thresholder. Needed to rebuild coordinates.
*/
/* @{ */
int rect_left_;
int rect_top_;
int rect_width_;
int rect_height_;
int image_width_;
int image_height_;
/* @} */
private:
// A list of image filenames gets special consideration
bool ProcessPagesFileList(FILE *fp,
STRING *buf,
const char* retry_config, int timeout_millisec,
TessResultRenderer* renderer,
int tessedit_page_number);
// TIFF supports multipage so gets special consideration.
bool ProcessPagesMultipageTiff(const unsigned char *data,
size_t size,
const char* filename,
const char* retry_config,
int timeout_millisec,
TessResultRenderer* renderer,
int tessedit_page_number);
// There's currently no way to pass a document title from the
// Tesseract command line, and we have multiple places that choose
// to set the title to an empty string. Using a single named
// variable will hopefully reduce confusion if the situation changes
// in the future.
const char *unknown_title_ = "";
}; // class TessBaseAPI.
/** Escape a char string - remove &<>"' with HTML codes. */
STRING HOcrEscape(const char* text);
} // namespace tesseract.
#endif // TESSERACT_API_BASEAPI_H_