/********************************************************************** * 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 "allheaders.h" #ifdef USE_NLS #include #include #define _(x) gettext(x) #else #define _(x) (x) #endif #include "baseapi.h" #include "resultiterator.h" #include "mutableiterator.h" #include "thresholder.h" #include "tesseractclass.h" #include "pageres.h" #include "paragraphs.h" #include "tessvars.h" #include "control.h" #include "pgedit.h" #include "paramsd.h" #include "output.h" #include "globals.h" #include "edgblob.h" #include "equationdetect.h" #include "tessbox.h" #include "imgs.h" #include "imgtiff.h" #include "makerow.h" #include "permute.h" #include "otsuthr.h" #include "osdetect.h" #include "params.h" #ifdef _WIN32 #include "version.h" #endif 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; // Minimum believable resolution. Used as a default if there is no other // information, as it is safer to under-estimate than over-estimate. const int kMinCredibleResolution = 70; // Maximum believable resolution. const int kMaxCredibleResolution = 2400; TessBaseAPI::TessBaseAPI() : tesseract_(NULL), osd_tesseract_(NULL), equ_detect_(NULL), // Thresholder is initialized to NULL here, but will be set before use by: // A constructor of a derived API, SetThresholder(), or // created implicitly when used in InternalSetImage. thresholder_(NULL), paragraph_models_(NULL), block_list_(NULL), page_res_(NULL), input_file_(NULL), output_file_(NULL), datapath_(NULL), language_(NULL), last_oem_requested_(OEM_DEFAULT), recognition_done_(false), truth_cb_(NULL), rect_left_(0), rect_top_(0), rect_width_(0), rect_height_(0), image_width_(0), image_height_(0) { } TessBaseAPI::~TessBaseAPI() { End(); } /** * Returns the version identifier as a static string. Do not delete. */ const char* TessBaseAPI::Version() { return VERSION; } // 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_ == NULL) 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_ == NULL) output_file_ = new STRING(name); else *output_file_ = name; } bool TessBaseAPI::SetVariable(const char* name, const char* value) { if (tesseract_ == NULL) 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_ == NULL) 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( name, GlobalParams()->int_params, tesseract_->params()->int_params); if (p == NULL) return false; *value = (inT32)(*p); return true; } bool TessBaseAPI::GetBoolVariable(const char *name, bool *value) const { BoolParam *p = ParamUtils::FindParam( name, GlobalParams()->bool_params, tesseract_->params()->bool_params); if (p == NULL) return false; *value = (BOOL8)(*p); return true; } const char *TessBaseAPI::GetStringVariable(const char *name) const { StringParam *p = ParamUtils::FindParam( name, GlobalParams()->string_params, tesseract_->params()->string_params); return (p != NULL) ? p->string() : NULL; } bool TessBaseAPI::GetDoubleVariable(const char *name, double *value) const { DoubleParam *p = ParamUtils::FindParam( name, GlobalParams()->double_params, tesseract_->params()->double_params); if (p == NULL) 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 NULL will default to eng. // If numeric_mode is true, then only digits and Roman numerals will // be returned. // Returns 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 *vars_vec, const GenericVector *vars_values, bool set_only_non_debug_params) { // Default language is "eng". if (language == NULL) language = "eng"; // 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 NULL, in // which case tesseract_->lang is set to the Tesseract default ("eng"). if (tesseract_ != NULL && (datapath_ == NULL || language_ == NULL || *datapath_ != datapath || last_oem_requested_ != oem || (*language_ != language && tesseract_->lang != language))) { delete tesseract_; tesseract_ = NULL; } bool reset_classifier = true; if (tesseract_ == NULL) { reset_classifier = false; tesseract_ = new Tesseract; if (tesseract_->init_tesseract( datapath, output_file_ != NULL ? output_file_->string() : NULL, language, oem, configs, configs_size, vars_vec, vars_values, set_only_non_debug_params) != 0) { return -1; } } // Update datapath and language requested for the last valid initialization. if (datapath_ == NULL) datapath_ = new STRING(datapath); else *datapath_ = datapath; if (language_ == NULL) language_ = new STRING(language); else *language_ = language; last_oem_requested_ = oem; // For same language and datapath, just reset the adaptive classifier. if (reset_classifier) tesseract_->ResetAdaptiveClassifier(); 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_ == NULL || language_->string() == NULL) ? "" : 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* langs) const { langs->clear(); if (tesseract_ != NULL) { 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); } } // 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_ == NULL) tesseract_ = new Tesseract; return tesseract_->init_tesseract_lm(datapath, NULL, language); } // 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_ == NULL) { tesseract_ = new Tesseract; tesseract_->InitAdaptiveClassifier(false); } } // 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_ == NULL) tesseract_ = new Tesseract; tesseract_->tessedit_pageseg_mode.set_value(mode); } // Return the current page segmentation mode. PageSegMode TessBaseAPI::GetPageSegMode() const { if (tesseract_ == NULL) return PSM_SINGLE_BLOCK; return static_cast( static_cast(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_ == NULL || width < kMinRectSize || height < kMinRectSize) return NULL; // 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(); } // Call between pages or documents etc to free up memory and forget // adaptive data. void TessBaseAPI::ClearAdaptiveClassifier() { if (tesseract_ == NULL) return; tesseract_->ResetAdaptiveClassifier(); tesseract_->ResetDocumentDictionary(); } // Provide an image for Tesseract to recognize. Format is as // TesseractRect above. Does not copy the image buffer, or take // ownership. The source image may be destroyed after Recognize is called, // either explicitly or implicitly via one of the Get*Text functions. // 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); } 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 doesn't take a copy or ownership or pixDestroy the image, so // it must persist until after Recognize. // Pix vs raw, which to use? // Use Pix where possible. A future version of Tesseract may choose to use Pix // as its internal representation and discard IMAGE altogether. // Because of that, an implementation that sources and targets Pix may end up // with less copies than an implementation that does not. void TessBaseAPI::SetImage(const Pix* pix) { if (InternalSetImage()) thresholder_->SetImage(pix); } // 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_ == NULL) return; thresholder_->SetRectangle(left, top, width, height); ClearResults(); } // ONLY available if you have Leptonica installed. // Get a copy of the internal thresholded image from Tesseract. Pix* TessBaseAPI::GetThresholdedImage() { if (tesseract_ == NULL) return NULL; if (tesseract_->pix_binary() == NULL) Threshold(tesseract_->mutable_pix_binary()); 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, NULL); } // Get the textlines as a leptonica-style Boxa, Pixa pair, in reading order. // Can be called before or after Recognize. // If blockids is not NULL, the block-id of each line is also returned as an // array of one element per line. delete [] after use. Boxa* TessBaseAPI::GetTextlines(Pixa** pixa, int** blockids) { return GetComponentImages(RIL_TEXTLINE, true, pixa, blockids); } // 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 NULL, 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, NULL); } // 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, NULL); } // 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 NULL, 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, Pixa** pixa, int** blockids) { PageIterator* page_it = GetIterator(); if (page_it == NULL) page_it = AnalyseLayout(); if (page_it == NULL) return NULL; // Failed. // Count the components to get a size for the arrays. int component_count = 0; int left, top, right, bottom; do { if (page_it->BoundingBoxInternal(level, &left, &top, &right, &bottom) && (!text_only || PTIsTextType(page_it->BlockType()))) ++component_count; } while (page_it->Next(level)); Boxa* boxa = boxaCreate(component_count); if (pixa != NULL) *pixa = pixaCreate(component_count); if (blockids != NULL) *blockids = new int[component_count]; int blockid = 0; int component_index = 0; page_it->Begin(); do { if (page_it->BoundingBoxInternal(level, &left, &top, &right, &bottom) && (!text_only || PTIsTextType(page_it->BlockType()))) { Box* lbox = boxCreate(left, top, right - left, bottom - top); boxaAddBox(boxa, lbox, L_INSERT); if (pixa != NULL) { Pix* pix = page_it->GetBinaryImage(level); pixaAddPix(*pixa, pix, L_INSERT); pixaAddBox(*pixa, lbox, L_CLONE); } if (blockids != NULL) { (*blockids)[component_index] = blockid; if (page_it->IsAtFinalElement(RIL_BLOCK, level)) ++blockid; } ++component_index; } } while (page_it->Next(level)); delete page_it; return boxa; } int TessBaseAPI::GetThresholdedImageScaleFactor() const { if (thresholder_ == NULL) { return 0; } return thresholder_->GetScaleFactor(); } // Dump the internal binary image to a PGM file. void TessBaseAPI::DumpPGM(const char* filename) { if (tesseract_ == NULL) return; FILE *fp = fopen(filename, "wb"); Pix* pix = tesseract_->pix_binary(); int width = pixGetWidth(pix); int height = pixGetHeight(pix); l_uint32* data = pixGetData(pix); fprintf(fp, "P5 %d %d 255\n", width, height); for (int y = 0; y < height; ++y, data += pixGetWpl(pix)) { for (int x = 0; x < width; ++x) { uinT8 b = GET_DATA_BIT(data, x) ? 0 : 255; fwrite(&b, 1, 1, fp); } } fclose(fp); } // Placeholder for call to Cube and test that the input data is correct. // reskew is the direction of baselines in the skewed image in // normalized (cos theta, sin theta) form, so (0.866, 0.5) would represent // a 30 degree anticlockwise skew. int CubeAPITest(Boxa* boxa_blocks, Pixa* pixa_blocks, Boxa* boxa_words, Pixa* pixa_words, const FCOORD& reskew, Pix* page_pix, PAGE_RES* page_res) { int block_count = boxaGetCount(boxa_blocks); ASSERT_HOST(block_count == pixaGetCount(pixa_blocks)); // Write each block to the current directory as junk_write_display.nnn.png. for (int i = 0; i < block_count; ++i) { Pix* pix = pixaGetPix(pixa_blocks, i, L_CLONE); pixDisplayWrite(pix, 1); } int word_count = boxaGetCount(boxa_words); ASSERT_HOST(word_count == pixaGetCount(pixa_words)); int pr_word = 0; PAGE_RES_IT page_res_it(page_res); for (page_res_it.restart_page(); page_res_it.word () != NULL; page_res_it.forward(), ++pr_word) { WERD_RES *word = page_res_it.word(); WERD_CHOICE* choice = word->best_choice; // Write the first 100 words to files names wordims/.tif. if (pr_word < 100) { STRING filename("wordims/"); if (choice != NULL) { filename += choice->unichar_string(); } else { char numbuf[32]; filename += "unclassified"; snprintf(numbuf, 32, "%03d", pr_word); filename += numbuf; } filename += ".tif"; Pix* pix = pixaGetPix(pixa_words, pr_word, L_CLONE); pixWrite(filename.string(), pix, IFF_TIFF_G4); } } ASSERT_HOST(pr_word == word_count); return 0; } // 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. // Returns NULL 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() { if (FindLines() == 0) { if (block_list_->empty()) return NULL; // The page was empty. page_res_ = new PAGE_RES(block_list_, NULL); return new PageIterator(page_res_, tesseract_, thresholder_->GetScaleFactor(), thresholder_->GetScaledYResolution(), rect_left_, rect_top_, rect_width_, rect_height_); } return NULL; } // Recognize the tesseract global image and return the result as Tesseract // internal structures. int TessBaseAPI::Recognize(ETEXT_DESC* monitor) { if (tesseract_ == NULL) return -1; if (FindLines() != 0) return -1; if (page_res_ != NULL) delete page_res_; tesseract_->SetBlackAndWhitelist(); recognition_done_ = true; 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 page_res_ = new PAGE_RES(block_list_, &tesseract_->prev_word_best_choice_); if (tesseract_->tessedit_make_boxes_from_boxes) { tesseract_->CorrectClassifyWords(page_res_); return 0; } if (truth_cb_ != NULL) { tesseract_->wordrec_run_blamer.set_value(true); truth_cb_->Run(tesseract_->getDict().getUnicharset(), image_height_, page_res_); } int result = 0; if (tesseract_->interactive_display_mode) { tesseract_->pgeditor_main(rect_width_, rect_height_, page_res_); // 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_ = NULL; return -1; } else if (tesseract_->tessedit_train_from_boxes) { tesseract_->ApplyBoxTraining(*output_file_, 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); } else { // Now run the main recognition. if (tesseract_->recog_all_words(page_res_, monitor, NULL, NULL, 0)) { int paragraph_debug_level = 0; GetIntVariable("paragraph_debug_level", ¶graph_debug_level); DetectParagraphs(paragraph_debug_level); } else { result = -1; } } return result; } // Tests the chopper by exhaustively running chop_one_blob. int TessBaseAPI::RecognizeForChopTest(ETEXT_DESC* monitor) { if (tesseract_ == NULL) return -1; if (thresholder_ == NULL || thresholder_->IsEmpty()) { tprintf("Please call SetImage before attempting recognition."); return -1; } if (page_res_ != NULL) 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(block_list_, &(tesseract_->prev_word_best_choice_)); PAGE_RES_IT page_res_it(page_res_); while (page_res_it.word() != NULL) { WERD_RES *word_res = page_res_it.word(); GenericVector boxes; tesseract_->MaximallyChopWord(boxes, page_res_it.block()->block, page_res_it.row()->row, word_res); page_res_it.forward(); } return 0; } // Recognizes all the pages in the named file, as a multi-page tiff or // list of filenames, or single image, and gets the appropriate kind of text // according to parameters: tessedit_create_boxfile, // tessedit_make_boxes_from_boxes, tessedit_write_unlv, tessedit_create_hocr. // Calls ProcessPage on each page in the input file, which may be a // multi-page tiff, single-page other file format, or a plain text list of // images to read. If tessedit_page_number is non-negative, processing begins // at that page of a multi-page tiff file, or filelist. // The text is returned in text_out. Returns false on error. // If non-zero timeout_millisec terminates processing after the timeout on // a single page. // If non-NULL and non-empty, and some page fails for some reason, // the page is reprocessed with the retry_config config file. Useful // for interactively debugging a bad page. bool TessBaseAPI::ProcessPages(const char* filename, const char* retry_config, int timeout_millisec, STRING* text_out) { int page = tesseract_->tessedit_page_number; if (page < 0) page = 0; FILE* fp = fopen(filename, "rb"); if (fp == NULL) { tprintf(_("Image file %s cannot be opened!\n"), filename); return false; } // Find the number of pages if a tiff file, or zero otherwise. int npages = CountTiffPages(fp); fclose(fp); if (tesseract_->tessedit_create_hocr) { *text_out = "\n" "\n\n\n" "\n\n" "\n\n"; } else { *text_out = ""; } bool success = true; Pix *pix; if (npages > 0) { for (; page < npages && (pix = pixReadTiff(filename, page)) != NULL; ++page) { if (page >= 0) tprintf(_("Page %d\n"), page); char page_str[kMaxIntSize]; snprintf(page_str, kMaxIntSize - 1, "%d", page); SetVariable("applybox_page", page_str); success &= ProcessPage(pix, page, filename, retry_config, timeout_millisec, text_out); pixDestroy(&pix); if (tesseract_->tessedit_page_number >= 0 || npages == 1) { break; } } } else { // The file is not a tiff file, so use the general pixRead function. pix = pixRead(filename); if (pix != NULL) { success &= ProcessPage(pix, 0, filename, retry_config, timeout_millisec, text_out); pixDestroy(&pix); } else { // The file is not an image file, so try it as a list of filenames. FILE* fimg = fopen(filename, "rb"); if (fimg == NULL) { tprintf(_("File %s cannot be opened!\n"), filename); return false; } tprintf(_("Reading %s as a list of filenames...\n"), filename); char pagename[MAX_PATH]; // Skip to the requested page number. for (int i = 0; i < page && fgets(pagename, sizeof(pagename), fimg) != NULL; ++i); while (fgets(pagename, sizeof(pagename), fimg) != NULL) { chomp_string(pagename); pix = pixRead(pagename); if (pix == NULL) { tprintf(_("Image file %s cannot be read!\n"), pagename); fclose(fimg); return false; } tprintf(_("Page %d : %s\n"), page, pagename); success &= ProcessPage(pix, page, pagename, retry_config, timeout_millisec, text_out); pixDestroy(&pix); ++page; } fclose(fimg); } } if (tesseract_->tessedit_create_hocr) *text_out += "\n\n"; return success; } // Recognizes a single page for ProcessPages, appending the text to text_out. // 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. // If non-zero timeout_millisec terminates processing after the timeout. // If non-NULL and non-empty, and some page fails for some reason, // the page is reprocessed with the retry_config config file. Useful // for interactively debugging a bad page. // The text is returned in text_out. Returns false on error. bool TessBaseAPI::ProcessPage(Pix* pix, int page_index, const char* filename, const char* retry_config, int timeout_millisec, STRING* text_out) { SetInputName(filename); SetImage(pix); bool failed = false; if (timeout_millisec > 0) { // Running with a timeout. ETEXT_DESC monitor; monitor.cancel = NULL; monitor.cancel_this = NULL; monitor.set_deadline_msecs(timeout_millisec); // Now run the main recognition. failed = Recognize(&monitor) < 0; } else if (tesseract_->tessedit_pageseg_mode == PSM_OSD_ONLY || tesseract_->tessedit_pageseg_mode == PSM_AUTO_ONLY) { // Disabled character recognition. PageIterator* it = AnalyseLayout(); if (it == NULL) { failed = true; } else { delete it; return true; } } else { // Normal layout and character recognition with no timeout. failed = Recognize(NULL) < 0; } if (tesseract_->tessedit_write_images) { Pix* page_pix = GetThresholdedImage(); pixWrite("tessinput.tif", page_pix, IFF_TIFF_G4); } if (failed && retry_config != NULL && retry_config[0] != '\0') { // Save current config variables before switching modes. FILE* fp = fopen(kOldVarsFile, "wb"); PrintVariables(fp); fclose(fp); // Switch to alternate mode for retry. ReadConfigFile(retry_config); SetImage(pix); Recognize(NULL); // Restore saved config variables. ReadConfigFile(kOldVarsFile); } // Get text only if successful. if (!failed) { char* text; if (tesseract_->tessedit_create_boxfile || tesseract_->tessedit_make_boxes_from_boxes) { text = GetBoxText(page_index); } else if (tesseract_->tessedit_write_unlv) { text = GetUNLVText(); } else if (tesseract_->tessedit_create_hocr) { text = GetHOCRText(page_index); } else { text = GetUTF8Text(); } *text_out += text; delete [] text; return true; } return false; } // 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_ == NULL || page_res_ == NULL) return NULL; 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_ == NULL || page_res_ == NULL) return NULL; 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_ == NULL || page_res_ == NULL) return NULL; 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_ == NULL || (!recognition_done_ && Recognize(NULL) < 0)) return NULL; STRING text(""); ResultIterator *it = GetIterator(); do { if (it->Empty(RIL_PARA)) continue; char *para_text = it->GetUTF8Text(RIL_PARA); text += para_text; delete []para_text; } 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 AddBoxTohOCR(const PageIterator *it, PageIteratorLevel level, STRING* hocr_str) { int left, top, right, bottom; it->BoundingBox(level, &left, &top, &right, &bottom); hocr_str->add_str_int("' title=\"bbox ", left); hocr_str->add_str_int(" ", top); hocr_str->add_str_int(" ", right); hocr_str->add_str_int(" ", bottom); *hocr_str += "\">"; } // 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. // Image name/input_file_ can be set by SetInputName before calling // GetHOCRText // STL removed from original patch submission and refactored by rays. char* TessBaseAPI::GetHOCRText(int page_number) { if (tesseract_ == NULL || (page_res_ == NULL && Recognize(NULL) < 0)) return NULL; int lcnt = 1, bcnt = 1, pcnt = 1, wcnt = 1; int page_id = page_number + 1; // hOCR uses 1-based page numbers. STRING hocr_str(""); if (input_file_ == NULL) SetInputName(NULL); hocr_str.add_str_int("
\n"; ResultIterator *res_it = GetIterator(); for (; !res_it->Empty(RIL_BLOCK); wcnt++) { if (res_it->Empty(RIL_WORD)) { res_it->Next(RIL_WORD); continue; } // Open any new block/paragraph/textline. if (res_it->IsAtBeginningOf(RIL_BLOCK)) { hocr_str.add_str_int("
': hocr_str += ">"; break; case '&': hocr_str += "&"; break; case '"': hocr_str += """; break; case '\'': hocr_str += "'"; break; default: hocr_str += grapheme; } } else { hocr_str += grapheme; } } res_it->Next(RIL_SYMBOL); } while (!res_it->Empty(RIL_BLOCK) && !res_it->IsAtBeginningOf(RIL_WORD)); if (italic) hocr_str += ""; if (bold) hocr_str += ""; hocr_str += " "; wcnt++; // Close any ending block/paragraph/textline. if (last_word_in_line) { hocr_str += "\n"; lcnt++; } if (last_word_in_para) { hocr_str += "

\n"; pcnt++; } if (last_word_in_block) { hocr_str += "
\n"; bcnt++; } } hocr_str += "
\n"; char *ret = new char[hocr_str.length() + 1]; strcpy(ret, hocr_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 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 kBytesPerBlob = kNumbersPerBlob * (kBytesPerNumber + 1) + 1; const int kBytesPerBoxFileLine = (kBytesPerNumber + 1) * kNumbersPerBlob + 1; // Max bytes in the decimal representation of inT64. 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 and must be freed with the delete [] operator. // page_number is a 0-base page index that will appear in the box file. char* TessBaseAPI::GetBoxText(int page_number) { if (tesseract_ == NULL || (!recognition_done_ && Recognize(NULL) < 0)) return NULL; int blob_count; int utf8_length = TextLength(&blob_count); int total_length = blob_count * kBytesPerBoxFileLine + utf8_length + kMaxBytesPerLine; char* result = new char[total_length]; int output_length = 0; LTRResultIterator* it = GetLTRIterator(); do { int left, top, right, bottom; if (it->BoundingBox(RIL_SYMBOL, &left, &top, &right, &bottom)) { 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, left, image_height_ - bottom, right, image_height_ - top, page_number); output_length += strlen(result + output_length); delete [] text; // 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 // and must be freed with the delete [] operator. char* TessBaseAPI::GetUNLVText() { if (tesseract_ == NULL || (!recognition_done_ && Recognize(NULL) < 0)) return NULL; bool tilde_crunch_written = false; bool last_char_was_newline = true; bool last_char_was_tilde = false; int total_length = TextLength(NULL); 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 () != NULL; 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 preceeding 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(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; } // 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_ == NULL || (!recognition_done_ && Recognize(NULL) < 0)) return NULL; int n_word = 0; PAGE_RES_IT res_it(page_res_); for (res_it.restart_page(); res_it.word() != NULL; res_it.forward()) n_word++; int* conf = new int[n_word+1]; n_word = 0; for (res_it.restart_page(); res_it.word() != NULL; res_it.forward()) { WERD_RES *word = res_it.word(); WERD_CHOICE* choice = word->best_choice; int w_conf = static_cast(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; } /** * 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"); char* text = GetUTF8Text(); if (debug) { tprintf("Trying to adapt \"%s\" to \"%s\"\n", text, wordstr); } if (text != NULL) { PAGE_RES_IT it(page_res_); WERD_RES* word_res = it.word(); if (word_res != NULL) { word_res->word->set_text(wordstr); } else { success = false; } // Check to see if text matches wordstr. int w = 0; int t = 0; for (t = 0; text[t] != '\0'; ++t) { if (text[t] == '\n' || text[t] == ' ') continue; while (wordstr[w] != '\0' && wordstr[w] == ' ') ++w; if (text[t] != wordstr[w]) break; ++w; } if (text[t] != '\0' || wordstr[w] != '\0') { // No match. delete page_res_; GenericVector 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() == NULL) success = false; else word_res = pr_it.word(); } else { word_res->BestChoiceToCorrectText(); } if (success) { tesseract_->EnableLearning = true; tesseract_->LearnWord(NULL, NULL, word_res); } delete [] text; } else { success = false; } SetPageSegMode(current_psm); return success; } // 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_ != NULL) thresholder_->Clear(); ClearResults(); } // 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() { if (thresholder_ != NULL) { delete thresholder_; thresholder_ = NULL; } if (page_res_ != NULL) { delete page_res_; page_res_ = NULL; } if (block_list_ != NULL) { delete block_list_; block_list_ = NULL; } if (paragraph_models_ != NULL) { paragraph_models_->delete_data_pointers(); delete paragraph_models_; paragraph_models_ = NULL; } if (tesseract_ != NULL) { delete tesseract_; if (osd_tesseract_ == tesseract_) osd_tesseract_ = NULL; tesseract_ = NULL; } if (osd_tesseract_ != NULL) { delete osd_tesseract_; osd_tesseract_ = NULL; } if (equ_detect_ != NULL) { delete equ_detect_; equ_detect_ = NULL; } if (input_file_ != NULL) { delete input_file_; input_file_ = NULL; } if (output_file_ != NULL) { delete output_file_; output_file_ = NULL; } if (datapath_ != NULL) { delete datapath_; datapath_ = NULL; } if (language_ != NULL) { delete language_; language_ = NULL; } } // 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); } bool TessBaseAPI::GetTextDirection(int* out_offset, float* out_slope) { if (page_res_ == NULL) FindLines(); if (block_list_->length() < 1) { return false; } // Get first block BLOCK_IT block_it(block_list_); block_it.move_to_first(); ROW_LIST* rows = block_it.data()->row_list(); if (rows->length() < 1) { return false; } // Get first line of block ROW_IT row_it(rows); row_it.move_to_first(); ROW* row = row_it.data(); // Calculate offset and slope (NOTE: Kind of ugly) *out_offset = static_cast(row->base_line(0.0)); *out_slope = row->base_line(1.0) - row->base_line(0.0); return true; } // Sets Dict::letter_is_okay_ function to point to the given function. void TessBaseAPI::SetDictFunc(DictFunc f) { if (tesseract_ != NULL) { tesseract_->getDict().letter_is_okay_ = f; } } // Sets Dict::probability_in_context_ function to point to the given function. void TessBaseAPI::SetProbabilityInContextFunc(ProbabilityInContextFunc f) { if (tesseract_ != NULL) { 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; } } } // Sets Wordrec::fill_lattice_ function to point to the given function. void TessBaseAPI::SetFillLatticeFunc(FillLatticeFunc f) { if (tesseract_ != NULL) tesseract_->fill_lattice_ = f; } // Common code for setting the image. bool TessBaseAPI::InternalSetImage() { if (tesseract_ == NULL) { tprintf("Please call Init before attempting to send an image."); return false; } if (thresholder_ == NULL) thresholder_ = new ImageThresholder; ClearResults(); return true; } // Run the thresholder to make the thresholded image, returned in pix, // which must not be NULL. *pix must be initialized to NULL, or point // to an existing pixDestroyable Pix. // The usual argument to Threshold is Tesseract::mutable_pix_binary(). void TessBaseAPI::Threshold(Pix** pix) { ASSERT_HOST(pix != NULL); if (!thresholder_->IsBinary()) { tesseract_->set_pix_grey(thresholder_->GetPixRectGrey()); } if (*pix != NULL) pixDestroy(pix); // Zero resolution messes up the algorithms, so make sure it is credible. int y_res = thresholder_->GetScaledYResolution(); if (y_res < kMinCredibleResolution || y_res > kMaxCredibleResolution) { // Use the minimum default resolution, as it is safer to under-estimate // than over-estimate resolution. thresholder_->SetSourceYResolution(kMinCredibleResolution); } thresholder_->ThresholdToPix(pix); thresholder_->GetImageSizes(&rect_left_, &rect_top_, &rect_width_, &rect_height_, &image_width_, &image_height_); // 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 resolution %d out of range! Corrected to %d\n", thresholder_->GetScaledEstimatedResolution(), estimated_res); } tesseract_->set_source_resolution(estimated_res); } // Find lines from the image making the BLOCK_LIST. int TessBaseAPI::FindLines() { if (thresholder_ == NULL || thresholder_->IsEmpty()) { tprintf("Please call SetImage before attempting recognition."); return -1; } if (recognition_done_) ClearResults(); if (!block_list_->empty()) { return 0; } if (tesseract_ == NULL) { tesseract_ = new Tesseract; tesseract_->InitAdaptiveClassifier(false); } if (tesseract_->pix_binary() == NULL) Threshold(tesseract_->mutable_pix_binary()); if (tesseract_->ImageWidth() > MAX_INT16 || tesseract_->ImageHeight() > MAX_INT16) { tprintf("Image too large: (%d, %d)\n", tesseract_->ImageWidth(), tesseract_->ImageHeight()); return -1; } tesseract_->PrepareForPageseg(); if (tesseract_->textord_equation_detect) { if (equ_detect_ == NULL && datapath_ != NULL) { equ_detect_ = new EquationDetect(datapath_->string(), NULL); } tesseract_->SetEquationDetect(equ_detect_); } Tesseract* osd_tess = osd_tesseract_; OSResults osr; if (PSM_OSD_ENABLED(tesseract_->tessedit_pageseg_mode) && osd_tess == NULL) { if (strcmp(language_->string(), "osd") == 0) { osd_tess = tesseract_; } else { osd_tesseract_ = new Tesseract; if (osd_tesseract_->init_tesseract( datapath_->string(), NULL, "osd", OEM_TESSERACT_ONLY, NULL, 0, NULL, NULL, false) == 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_ = NULL; } } } 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_ != NULL) { tesseract_->Clear(); } if (page_res_ != NULL) { delete page_res_; page_res_ = NULL; } recognition_done_ = false; if (block_list_ == NULL) block_list_ = new BLOCK_LIST; else block_list_->clear(); if (paragraph_models_ != NULL) { paragraph_models_->delete_data_pointers(); delete paragraph_models_; paragraph_models_ = NULL; } } // 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_ == NULL || page_res_ == NULL) 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 () != NULL; page_res_it.forward()) { WERD_RES *word = page_res_it.word(); WERD_CHOICE* choice = word->best_choice; if (choice != NULL) { 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 != NULL) *blob_count = total_blobs; return total_length; } // Estimates the Orientation And Script of the image. // Returns true if the image was processed successfully. bool TessBaseAPI::DetectOS(OSResults* osr) { if (tesseract_ == NULL) return false; ClearResults(); if (tesseract_->pix_binary() == NULL) Threshold(tesseract_->mutable_pix_binary()); if (input_file_ == NULL) input_file_ = new STRING(kInputFile); return orientation_and_script_detection(*input_file_, osr, tesseract_); } 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 = NULL; delete[] *vertical_writing; *vertical_writing = NULL; 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()->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()->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 / PI; if (rot_theta < 0) rot_theta += 4; int num_rotations = static_cast(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; } } // ____________________________________________________________________________ // Ocropus add-ons. // Find lines from the image making the BLOCK_LIST. BLOCK_LIST* TessBaseAPI::FindLinesCreateBlockList() { FindLines(); BLOCK_LIST* result = block_list_; block_list_ = NULL; 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 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 NULL; // 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(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, DENORM *denorm) { TWERD word; word.blobs = tblob; if (denorm != NULL) { word.SetupBLNormalize(NULL, row, row->x_height(), numeric_mode, denorm); word.Normalize(*denorm); } else { DENORM normer; word.SetupBLNormalize(NULL, row, row->x_height(), numeric_mode, &normer); word.Normalize(normer); } word.blobs = NULL; } // Return a TBLOB * from the whole pix. // To be freed later with delete. 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, NULL); 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; UNICHAR_ID best_class = 0; float best_rating = -100; // Classify to get a raw choice. BLOB_CHOICE_LIST choices; DENORM denorm; tesseract_->AdaptiveClassifier(blob, denorm, &choices, NULL); 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(); best_class = choice_it.data()->unichar_id(); } } threshold = tesseract_->matcher_good_threshold; if (blob->outlines) tesseract_->AdaptToChar(blob, denorm, id, kUnknownFontinfoId, threshold); delete blob; } PAGE_RES* TessBaseAPI::RecognitionPass1(BLOCK_LIST* block_list) { PAGE_RES *page_res = new PAGE_RES(block_list, &(tesseract_->prev_word_best_choice_)); tesseract_->recog_all_words(page_res, NULL, NULL, NULL, 1); return page_res; } PAGE_RES* TessBaseAPI::RecognitionPass2(BLOCK_LIST* block_list, PAGE_RES* pass1_result) { if (!pass1_result) pass1_result = new PAGE_RES(block_list, &(tesseract_->prev_word_best_choice_)); tesseract_->recog_all_words(pass1_result, NULL, NULL, NULL, 2); return pass1_result; } void TessBaseAPI::DetectParagraphs(int debug_level) { if (paragraph_models_ == NULL) paragraph_models_ = new GenericVector; MutableIterator *result_it = GetMutableIterator(); do { // Detect paragraphs for this block GenericVector models; ::tesseract::DetectParagraphs(debug_level, result_it, &models); *paragraph_models_ += models; } while (result_it->Next(RIL_BLOCK)); delete result_it; } 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() { // 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() != NULL) { 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. void TessBaseAPI::GetFeaturesForBlob(TBLOB* blob, const DENORM& denorm, INT_FEATURE_ARRAY int_features, int* num_features, int* FeatureOutlineIndex) { if (tesseract_) { tesseract_->ResetFeaturesHaveBeenExtracted(); } uinT8* norm_array = new uinT8[MAX_NUM_CLASSES]; inT32 len; *num_features = tesseract_->GetCharNormFeatures( blob, denorm, tesseract_->PreTrainedTemplates, int_features, norm_array, norm_array, &len, FeatureOutlineIndex); delete [] norm_array; } // This method returns the row to which a box of specified dimensions would // belong. If no good match is found, it returns NULL. 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->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 NULL; } // Method to run adaptive classifier on a blob. void TessBaseAPI::RunAdaptiveClassifier(TBLOB* blob, const DENORM& denorm, int num_max_matches, int* unichar_ids, float* ratings, int* num_matches_returned) { BLOB_CHOICE_LIST* choices = new BLOB_CHOICE_LIST; tesseract_->AdaptiveClassifier(blob, denorm, choices, NULL); 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; } // 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_ == NULL || i >= NumDawgs()) return NULL; return tesseract_->getDict().GetDawg(i); } // Return the number of dawgs loaded into tesseract_ object. int TessBaseAPI::NumDawgs() const { return tesseract_ == NULL ? 0 : tesseract_->getDict().NumDawgs(); } // Return a pointer to underlying CubeRecoContext object if present. CubeRecoContext *TessBaseAPI::GetCubeRecoContext() const { return (tesseract_ == NULL) ? NULL : tesseract_->GetCubeRecoContext(); } } // namespace tesseract.