Bundle multiple tesseract versions

Load them via C api and allow user to select which one to use.

.github/workflows/build.yml

@@ -33,18 +33,13 @@ jobs:
     runs-on: ${{ matrix.config.os }}
     env:
       OS: ${{ matrix.config.name }}
-      MARCH: ${{ matrix.config.march }}
-      TAG: ${{ matrix.config.tag }}
       MSVC_VERSION: 2019/Enterprise
     strategy:
       matrix:
         config:
-          - { name: "win64", os: windows-latest, tag: "", march: "sandy-bridge" }
+          - { name: "win64", os: windows-latest }
-          - { name: "win32", os: windows-latest, tag: "", march: "sandy-bridge" }
+          - { name: "win32", os: windows-latest }
-          - { name: "linux", os: ubuntu-16.04, tag: "", march: "sandy-bridge" }
+          - { name: "linux", os: ubuntu-16.04 }
-          - { name: "win64", os: windows-latest, tag: "-compatible", march: "nehalem" }
-          - { name: "win32", os: windows-latest, tag: "-compatible", march: "nehalem" }
-          - { name: "linux", os: ubuntu-16.04, tag: "-compatible", march: "nehalem" }
           # - { name: "macos", os: macos-latest }
     steps:
       - uses: actions/checkout@v2
@@ -66,7 +61,7 @@ jobs:
         uses: actions/cache@v1
         with:
           path: deps
-          key: ${{ env.OS }}-${{ env.TAG }}-deps
+          key: ${{ env.OS }}-deps
 
       - name: Get Qt
         run: python ./share/ci/get_qt.py
@@ -77,7 +72,16 @@ jobs:
       - name: Get leptonica
         run: python ./share/ci/get_leptonica.py
 
-      - name: Get tesseract
+      - name: Get tesseract optimized
+        env:
+          MARCH: sandy-bridge
+          TAG: optimized
+        run: python ./share/ci/get_tesseract.py
+
+      - name: Get tesseract compatible
+        env:
+          MARCH: nehalem
+          TAG: compatible
         run: python ./share/ci/get_tesseract.py
 
       - name: Get hunspell

screen-translator.pro

@@ -8,7 +8,7 @@ DEPS_DIR=$$(ST_DEPS_DIR)
 isEmpty(DEPS_DIR):DEPS_DIR=$$PWD/../deps
 INCLUDEPATH += $$DEPS_DIR/include
 LIBS += -L$$DEPS_DIR/lib
-LIBS += -ltesseract -lleptonica -lhunspell
+LIBS += -lhunspell -lleptonica
 
 win32{
   LIBS += -lUser32

share/ci/appimage.py

@@ -47,7 +47,8 @@ os.environ['VERSION'] = app_version
 flags = '' if os.getenv("DEBUG") is None else '-unsupported-allow-new-glibc'
 
 additional_files = glob(ssl_dir + '/lib/lib*.so.*') + \
-    glob('/usr/lib/x86_64-linux-gnu/nss/*')
+    glob('/usr/lib/x86_64-linux-gnu/nss/*') + \
+    glob(dependencies_dir + '/lib/libtesseract-*.so')
 out_lib_dir = install_dir + '/usr/lib'
 os.makedirs(out_lib_dir, exist_ok=True)
 for f in additional_files:

share/ci/get_tesseract.py

@@ -33,39 +33,33 @@ if os.environ.get('NO_OPT', '0') == '1':
 if len(os.environ.get('MARCH', '')) > 0:
     compat_flags += ' -D TARGET_ARCHITECTURE={} '.format(os.environ['MARCH'])
 
-cache_file = install_dir + '/tesseract.cache'
+lib_suffix = os.environ.get('TAG', '')
-cache_file_data = required_version + build_type_flag + compat_flags
+if len(lib_suffix) > 0:
+    lib_suffix = '-' + lib_suffix
 
 
 def check_existing():
-    if not os.path.exists(cache_file):
-        return False
-    with open(cache_file, 'r') as f:
-        cached = f.read()
-        if cached != cache_file_data:
-            return False
-
-    if platform.system() == "Windows":
-        dll = install_dir + '/bin/tesseract41.dll'
-        lib = install_dir + '/lib/tesseract41.lib'
-        if not os.path.exists(dll) or not os.path.exists(lib):
-            return False
-        c.symlink(dll, install_dir + '/bin/tesseract.dll')
-        c.symlink(lib, install_dir + '/lib/tesseract.lib')
-    elif platform.system() == "Darwin":
-        lib = install_dir + '/lib/libtesseract.4.1.1.dylib'
-        if not os.path.exists(lib):
-            return False
-        c.symlink(lib, install_dir + '/lib/libtesseract.dylib')
-    else:
-        if not os.path.exists(install_dir + '/lib/libtesseract.so'):
-            return False
-
     includes_path = install_dir + '/include/tesseract'
     if len(c.get_folder_files(includes_path)) == 0:
         return False
 
-    return True
+    if platform.system() == "Windows":
+        lib = install_dir + '/bin/tesseract{}.dll'.format(lib_suffix)
+        orig_lib = install_dir + '/bin/tesseract41.dll'
+    elif platform.system() == "Darwin":
+        lib = install_dir + '/lib/libtesseract{}.dylib'.format(lib_suffix)
+        orig_lib = install_dir + '/lib/libtesseract.4.1.1.dylib'
+    else:
+        lib = install_dir + '/lib/libtesseract{}.so'.format(lib_suffix)
+        orig_lib = install_dir + '/lib/libtesseract.so.4.1.1'
+
+    if os.path.exists(lib):
+        return True
+    if os.path.exists(orig_lib):
+        os.rename(orig_lib, lib)
+        return True
+
+    return False
 
 
 if check_existing() and not 'FORCE' in os.environ:
@@ -102,9 +96,6 @@ if len(compat_flags) > 0:
 c.run('cmake --build . --config {}'.format(build_type_flag))
 c.run('cmake --build . --target install --config {}'.format(build_type_flag))
 
-with open(cache_file, 'w') as f:
+if not check_existing():  # add suffix
-    f.write(cache_file_data)
-
-if not check_existing():  # create links
     c.print('>> Build failed')
     exit(1)

share/ci/windeploy.py

@@ -34,7 +34,9 @@ for file in os.scandir(libs_dir):
         c.print('>> Copying {} to {}'.format(full_name, install_dir))
         shutil.copy(full_name, install_dir)
 
-for f in glob(ssl_dir + '/bin/*.dll'):
+additional_libs = glob(ssl_dir + '/bin/*.dll') + \
+    glob(dependencies_dir + '/bin/tesseract-*.dll')
+for f in additional_libs:
     c.print('>> Copying {} to {}'.format(f, install_dir))
     shutil.copy(f, install_dir)
 

share/translations/screentranslator_ru.ts

@@ -66,7 +66,7 @@ Ctrl - продолжить выделять</translation>
 <context>
     <name>QObject</name>
     <message>
-        <location filename="../../src/main.cpp" line="28"/>
+        <location filename="../../src/main.cpp" line="30"/>
         <source>OCR and translation tool</source>
         <translation>Инструмент распознавания и перевода</translation>
     </message>
@@ -668,7 +668,7 @@ Check for updates to silence this warning</source>
         <translation>Начата запись в лог-файл: %1</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.cpp" line="104"/>
+        <location filename="../../src/settingseditor.cpp" line="112"/>
         <source>&lt;p&gt;Optical character recognition (OCR) and translation tool&lt;/p&gt;
         &lt;p&gt;Version: %1&lt;/p&gt;
         &lt;p&gt;Author: Gres (&lt;a href=&quot;mailto:%2&quot;&gt;%2&lt;/a&gt;)&lt;/p&gt;
@@ -684,12 +684,12 @@ Check for updates to silence this warning</source>
         <translation>неизвестные языки для перевода: %1 или %2</translation>
     </message>
     <message>
-        <location filename="../../src/ocr/tesseract.cpp" line="153"/>
+        <location filename="../../src/ocr/tesseract.cpp" line="238"/>
         <source>init failed</source>
         <translation>ошибка инициалиизации</translation>
     </message>
     <message>
-        <location filename="../../src/ocr/tesseract.cpp" line="211"/>
+        <location filename="../../src/ocr/tesseract.cpp" line="289"/>
         <source>Failed to recognize text or no text selected</source>
         <translation>Ошибка распознавания текста или нет текста в выделенной зоне</translation>
     </message>
@@ -734,7 +734,7 @@ in %1</source>
 <context>
     <name>Recognizer</name>
     <message>
-        <location filename="../../src/ocr/recognizer.cpp" line="36"/>
+        <location filename="../../src/ocr/recognizer.cpp" line="37"/>
         <source>No source language set. Check settings</source>
         <translation>Не задан исходный язык. Проверьте настройки</translation>
     </message>
@@ -870,37 +870,42 @@ in %1</source>
         <translation>сохранять пароль (небезопасно)</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="295"/>
+        <location filename="../../src/settingseditor.ui" line="291"/>
+        <source>Library version</source>
+        <translation>Версия</translation>
+    </message>
+    <message>
+        <location filename="../../src/settingseditor.ui" line="305"/>
         <source>User substitutions</source>
         <translation>Пользовательская коррекция</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="318"/>
+        <location filename="../../src/settingseditor.ui" line="328"/>
         <source>Use auto corrections (hunspell)</source>
         <translation>Использовать автокоррекцию (hunspell)</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="325"/>
+        <location filename="../../src/settingseditor.ui" line="335"/>
         <source>Use user substitutions</source>
         <translation>Использовать пользовательскую коррекцию</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="332"/>
+        <location filename="../../src/settingseditor.ui" line="342"/>
         <source>Hunspell dictionaries path:</source>
         <translation>Путь к словарям Hunspell:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="394"/>
+        <location filename="../../src/settingseditor.ui" line="404"/>
         <source>Language:</source>
         <translation>Язык:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="430"/>
+        <location filename="../../src/settingseditor.ui" line="440"/>
         <source> secs</source>
         <translation> сек</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="370"/>
+        <location filename="../../src/settingseditor.ui" line="380"/>
         <source>Ignore SSL errors</source>
         <translation>Игнорировать ошибки SSL</translation>
     </message>
@@ -930,107 +935,107 @@ in %1</source>
         <translation>Писать логи в файл (отладка)</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="239"/>
+        <location filename="../../src/settingseditor.ui" line="278"/>
         <source>Default language:</source>
         <translation>Язык по умолчанию:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="255"/>
+        <location filename="../../src/settingseditor.ui" line="265"/>
         <source>Tessdata path:</source>
         <translation>Путь к языкам (tessdata):</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="305"/>
+        <location filename="../../src/settingseditor.ui" line="315"/>
         <source>\\ for \ symbol, \n for newline</source>
         <translation>\\ для символа \ , \n для символа новой строки</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="353"/>
+        <location filename="../../src/settingseditor.ui" line="363"/>
         <source>Translators path:</source>
         <translation>Путь к переводчикам:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="360"/>
+        <location filename="../../src/settingseditor.ui" line="370"/>
         <source>Translators</source>
         <translation>Переводчики</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="495"/>
+        <location filename="../../src/settingseditor.ui" line="505"/>
         <source>Result window</source>
         <translation>Окно результата</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="501"/>
+        <location filename="../../src/settingseditor.ui" line="511"/>
         <source>Font:</source>
         <translation>Шрифт:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="511"/>
+        <location filename="../../src/settingseditor.ui" line="521"/>
         <source>Font size:</source>
         <translation>Размер шрифта:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="528"/>
+        <location filename="../../src/settingseditor.ui" line="538"/>
         <source>Font color:</source>
         <translation>Цвет шрифта:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="545"/>
+        <location filename="../../src/settingseditor.ui" line="555"/>
         <source>Background:</source>
         <translation>Фон:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="562"/>
+        <location filename="../../src/settingseditor.ui" line="572"/>
         <source>Show image</source>
         <translation>Показывать изображение</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="569"/>
+        <location filename="../../src/settingseditor.ui" line="579"/>
         <source>Show recognized</source>
         <translation>Показывать распознанное</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="638"/>
+        <location filename="../../src/settingseditor.ui" line="648"/>
         <source>Update check interval (days):</source>
         <translation>Интервал проверки обновления (дней):</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="645"/>
+        <location filename="../../src/settingseditor.ui" line="655"/>
         <source>0 - disabled</source>
         <translation>- отключено</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="678"/>
+        <location filename="../../src/settingseditor.ui" line="688"/>
         <source>Apply updates</source>
         <translation>Применить изменения</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="380"/>
+        <location filename="../../src/settingseditor.ui" line="390"/>
         <source>Translate text</source>
         <translation>Переводить текст</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="387"/>
+        <location filename="../../src/settingseditor.ui" line="397"/>
         <source>Single translator timeout:</source>
         <translation>Переходить к следующему переводчику после:</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="457"/>
+        <location filename="../../src/settingseditor.ui" line="467"/>
         <source>Result type</source>
         <translation>Тип результата</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="469"/>
+        <location filename="../../src/settingseditor.ui" line="479"/>
         <source>Tray</source>
         <translation>Трей</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="482"/>
+        <location filename="../../src/settingseditor.ui" line="492"/>
         <source>Window</source>
         <translation>Окно</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.ui" line="661"/>
+        <location filename="../../src/settingseditor.ui" line="671"/>
         <source>Check now</source>
         <translation>Проверить сейчас</translation>
     </message>
@@ -1090,17 +1095,32 @@ in %1</source>
         <translation>HTTP</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.cpp" line="66"/>
+        <location filename="../../src/settingseditor.cpp" line="57"/>
+        <source>Optimized</source>
+        <translation>Оптимизированная</translation>
+    </message>
+    <message>
+        <location filename="../../src/settingseditor.cpp" line="58"/>
+        <source>Compatible</source>
+        <translation>Совместимая</translation>
+    </message>
+    <message>
+        <location filename="../../src/settingseditor.cpp" line="62"/>
+        <source>Use compatible version if you are experiencing crashes during recognition</source>
+        <translation>Используйте совместимую версию если программа неожиданно завершается во время распознавания</translation>
+    </message>
+    <message>
+        <location filename="../../src/settingseditor.cpp" line="74"/>
         <source>&lt;b&gt;NOTE! Some translators might require the translation window to be visible. You can make it using the &quot;Show translator&quot; entry in the tray icon&apos;s context menu&lt;/b&gt;</source>
         <translation>&lt;b&gt;ПРИМЕЧАНИЕ! Для работы некоторых переводчиков может потребоваться активное окно перевода. Его можно отобразить при помощи пункта &quot;Показать окно перевода&quot; контекстного меню иконки в трее&lt;/b&gt;</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.cpp" line="74"/>
+        <location filename="../../src/settingseditor.cpp" line="82"/>
         <source>Sample text</source>
         <translation>Текст для проверки</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.cpp" line="115"/>
+        <location filename="../../src/settingseditor.cpp" line="123"/>
         <source>The program workflow consists of the following steps:
 1. Selection on the screen area
 2. Recognition of the selected area
@@ -1123,7 +1143,7 @@ Then set default recognition and translation languages, enable some (or all) tra
 Далее установите языки распознавания и перевода по умолчанию, активируйте некоторые (или все) переводчики и настройку &quot;переводить текст&quot;, если нужно.</translation>
     </message>
     <message>
-        <location filename="../../src/settingseditor.cpp" line="341"/>
+        <location filename="../../src/settingseditor.cpp" line="352"/>
         <source>Portable changed. Apply settings first</source>
         <translation>Portable режиме изменени. Сначала применить настройки</translation>
     </message>

src/ocr/recognizer.cpp

@@ -79,5 +79,9 @@ void Recognizer::updateSettings()
   SOFT_ASSERT(!settings_.tessdataPath.isEmpty(), return );
 
   queue_.clear();
-  emit reset(settings_.tessdataPath);
+  const auto libName =
+      (settings_.tesseractVersion == TesseractVersion::Optimized
+           ? "tesseract-optimized"
+           : "tesseract-compatible");
+  emit reset(settings_.tessdataPath, libName);
 }

src/ocr/recognizer.h

@@ -18,7 +18,7 @@ public:
 
 signals:
   void recognizeImpl(const TaskPtr &task);
-  void reset(const QString &tessdataPath);
+  void reset(const QString &tessdataPath, const QString &tesseractLibrary);
 
 private:
   void recognized(const TaskPtr &task);

src/ocr/recognizerworker.cpp

@@ -17,8 +17,8 @@ void RecognizeWorker::handle(const TaskPtr &task)
   if (!engines_.count(task->sourceLanguage)) {
     LTRACE() << "Create OCR engine" << task->sourceLanguage;
 
-    auto engine =
+    auto engine = std::make_unique<Tesseract>(task->sourceLanguage,
-        std::make_unique<Tesseract>(task->sourceLanguage, tessdataPath_);
+                                              tessdataPath_, tesseractLibrary_);
 
     if (!engine->isValid()) {
       result->error = tr("Failed to init OCR engine: %1").arg(engine->error());
@@ -43,12 +43,14 @@ void RecognizeWorker::handle(const TaskPtr &task)
   emit finished(result);
 }
 
-void RecognizeWorker::reset(const QString &tessdataPath)
+void RecognizeWorker::reset(const QString &tessdataPath,
+                            const QString &tesseractLibrary)
 {
-  if (tessdataPath_ == tessdataPath)
+  if (tessdataPath_ == tessdataPath && tesseractLibrary_ == tesseractLibrary)
     return;
 
   tessdataPath_ = tessdataPath;
+  tesseractLibrary_ = tesseractLibrary;
   engines_.clear();
   LTRACE() << "Cleared OCR engines";
 }

src/ocr/recognizerworker.h

@@ -13,7 +13,7 @@ public:
   ~RecognizeWorker();
 
   void handle(const TaskPtr &task);
-  void reset(const QString &tessdataPath);
+  void reset(const QString &tessdataPath, const QString &tesseractLibrary);
 
 signals:
   void finished(const TaskPtr &task);
@@ -24,4 +24,5 @@ private:
   std::map<QString, std::unique_ptr<Tesseract>> engines_;
   std::map<QString, Generation> lastGenerations_;
   QString tessdataPath_;
+  QString tesseractLibrary_;
 };

src/ocr/tesseract.cpp

@@ -4,10 +4,10 @@
 #include "task.h"
 
 #include <leptonica/allheaders.h>
-#include <tesseract/baseapi.h>
 
 #include <QBuffer>
 #include <QDir>
+#include <QLibrary>
 
 #if defined(Q_OS_LINUX)
 #include <fstream>
@@ -125,7 +125,103 @@ static void cleanupImage(Pix **image)
   pixDestroy(image);
 }
 
-Tesseract::Tesseract(const LanguageId &language, const QString &tessdataPath)
+// do not include capi.h from tesseract because it defined BOOL that breaks msvc
+struct TessBaseAPI;
+
+class Tesseract::Wrapper
+{
+  using CreateApi = TessBaseAPI *(*)();
+  using DeleteApi = void (*)(TessBaseAPI *);
+  using InitApi = int (*)(TessBaseAPI *, const char *, const char *, int);
+  using SetImage = void (*)(TessBaseAPI *, struct Pix *);
+  using GetUtf8 = char *(*)(TessBaseAPI *);
+  using ClearApi = void (*)(TessBaseAPI *);
+  using DeleteUtf8 = void (*)(const char *);
+
+public:
+  explicit Wrapper(const QString &libraryName)
+    : lib(libraryName)
+  {
+    if (!lib.load()) {
+      LERROR() << "Failed to load tesseract library" << libraryName;
+      return;
+    }
+
+    LTRACE() << "Loaded tesseract library" << lib.fileName();
+    auto ok = true;
+    ok &= bool(createApi_ = (CreateApi)lib.resolve("TessBaseAPICreate"));
+    ok &= bool(deleteApi_ = (DeleteApi)lib.resolve("TessBaseAPIDelete"));
+    ok &= bool(initApi_ = (InitApi)lib.resolve("TessBaseAPIInit2"));
+    ok &= bool(setImage_ = (SetImage)lib.resolve("TessBaseAPISetImage2"));
+    ok &= bool(getUtf8_ = (GetUtf8)lib.resolve("TessBaseAPIGetUTF8Text"));
+    ok &= bool(clearApi_ = (ClearApi)lib.resolve("TessBaseAPIClear"));
+    ok &= bool(deleteUtf8_ = (DeleteUtf8)lib.resolve("TessDeleteText"));
+    if (!ok) {
+      LERROR() << "Failed to resolve tesseract functions from" << libraryName;
+      return;
+    }
+    handle_ = createApi_();
+  }
+
+  ~Wrapper()
+  {
+    if (handle_ && deleteApi_) {
+      deleteApi_(handle_);
+    }
+    lib.unload();
+  }
+
+  int Init(const char *datapath, const char *language)
+  {
+    SOFT_ASSERT(handle_, return -1);
+    SOFT_ASSERT(initApi_, return -1);
+
+    const auto mode = 3;  // TessOcrEngineMode::OEM_DEFAULT
+    return initApi_(handle_, datapath, language, mode);
+  }
+
+  QString GetText(Pix *pix)
+  {
+    SOFT_ASSERT(handle_, return {});
+
+    SOFT_ASSERT(setImage_, return {});
+    setImage_(handle_, pix);
+    LTRACE() << "Set Pix to engine";
+
+    char *outText = nullptr;
+
+    SOFT_ASSERT(getUtf8_, return {});
+    outText = getUtf8_(handle_);
+    LTRACE() << "Received recognized text";
+
+    SOFT_ASSERT(clearApi_, return {});
+    clearApi_(handle_);
+    LTRACE() << "Cleared engine";
+
+    const auto result = QString(outText).trimmed();
+
+    SOFT_ASSERT(deleteUtf8_, return {});
+    deleteUtf8_(outText);
+    LTRACE() << "Cleared recognized text buffer";
+
+    return result;
+  }
+
+private:
+  QLibrary lib;
+  CreateApi createApi_{nullptr};
+  DeleteApi deleteApi_{nullptr};
+  InitApi initApi_{nullptr};
+  SetImage setImage_{nullptr};
+  GetUtf8 getUtf8_{nullptr};
+  ClearApi clearApi_{nullptr};
+  DeleteUtf8 deleteUtf8_{nullptr};
+  TessBaseAPI *handle_{nullptr};
+};
+
+Tesseract::Tesseract(const LanguageId &language, const QString &tessdataPath,
+                     const QString &tesseractLibrary)
+  : tesseractLibrary_(tesseractLibrary)
 {
   SOFT_ASSERT(!tessdataPath.isEmpty(), return );
   SOFT_ASSERT(!language.isEmpty(), return );
@@ -139,13 +235,12 @@ void Tesseract::init(const LanguageId &language, const QString &tessdataPath)
 {
   SOFT_ASSERT(!engine_, return );
 
-  engine_ = std::make_unique<tesseract::TessBaseAPI>();
+  engine_ = std::make_unique<Wrapper>(tesseractLibrary_);
   LTRACE() << "Created Tesseract api" << engine_.get();
 
   const auto tesseractName = LanguageCodes::tesseract(language);
   auto result =
-      engine_->Init(qPrintable(tessdataPath), qPrintable(tesseractName),
+      engine_->Init(qPrintable(tessdataPath), qPrintable(tesseractName));
-                    tesseract::OEM_DEFAULT);
   LTRACE() << "Inited Tesseract api" << result;
   if (result == 0)
     return;
@@ -194,19 +289,12 @@ QString Tesseract::recognize(const QPixmap &source)
   Pix *image = prepareImage(source.toImage());
   SOFT_ASSERT(image, return {});
   LTRACE() << "Preprocessed Pix for OCR" << image;
-  engine_->SetImage(image);
+
-  LTRACE() << "Set Pix to engine";
+  auto result = engine_->GetText(image);
-  char *outText = engine_->GetUTF8Text();
+
-  LTRACE() << "Received recognized text";
-  engine_->Clear();
-  LTRACE() << "Cleared engine";
   cleanupImage(&image);
   LTRACE() << "Cleared preprocessed Pix";
 
-  QString result = QString(outText).trimmed();
-  delete[] outText;
-  LTRACE() << "Cleared recognized text buffer";
-
   if (result.isEmpty())
     error_ = QObject::tr("Failed to recognize text or no text selected");
   return result;

src/ocr/tesseract.h

@@ -7,16 +7,13 @@
 #include <memory>
 
 class QPixmap;
-namespace tesseract
-{
-class TessBaseAPI;
-}
 class Task;
 
 class Tesseract
 {
 public:
-  Tesseract(const LanguageId& language, const QString& tessdataPath);
+  Tesseract(const LanguageId& language, const QString& tessdataPath,
+            const QString& tesseractLibrary);
   ~Tesseract();
 
   QString recognize(const QPixmap& source);
@@ -26,8 +23,10 @@ public:
   static QStringList availableLanguageNames(const QString& path);
 
 private:
+  class Wrapper;
   void init(const LanguageId& language, const QString& tessdataPath);
 
-  std::unique_ptr<tesseract::TessBaseAPI> engine_;
+  const QString tesseractLibrary_;
+  std::unique_ptr<Wrapper> engine_;
   QString error_;
 };

src/settings.cpp

@@ -30,6 +30,7 @@ const QString qs_showMessageOnStart = "showMessageOnStart";
 
 const QString qs_recogntionGroup = "Recognition";
 const QString qs_ocrLanguage = "language";
+const QString qs_tesseractVersion = "tesseractVersion";
 
 const QString qs_correctionGroup = "Correction";
 const QString qs_userSubstitutions = "userSubstitutions";
@@ -171,6 +172,7 @@ void Settings::save() const
 
   settings.beginGroup(qs_recogntionGroup);
   settings.setValue(qs_ocrLanguage, sourceLanguage);
+  settings.setValue(qs_tesseractVersion, int(tesseractVersion));
   settings.endGroup();
 
   settings.beginGroup(qs_correctionGroup);
@@ -257,6 +259,9 @@ void Settings::load()
 
   settings.beginGroup(qs_recogntionGroup);
   sourceLanguage = settings.value(qs_ocrLanguage, sourceLanguage).toString();
+  tesseractVersion = TesseractVersion(std::clamp(
+      settings.value(qs_tesseractVersion, int(tesseractVersion)).toInt(),
+      int(TesseractVersion::Optimized), int(TesseractVersion::Compatible)));
   settings.endGroup();
 
   settings.beginGroup(qs_correctionGroup);

src/settings.h

@@ -18,6 +18,8 @@ using Substitutions = std::unordered_multimap<LanguageId, Substitution>;
 
 enum class ProxyType { Disabled, System, Socks5, Http };
 
+enum class TesseractVersion { Optimized, Compatible };
+
 class Settings
 {
 public:
@@ -57,6 +59,7 @@ public:
 
   QString tessdataPath;
   QString sourceLanguage{"eng"};
+  TesseractVersion tesseractVersion{TesseractVersion::Optimized};
 
   bool doTranslation{true};
   bool ignoreSslErrors{false};

src/settingseditor.cpp

@@ -51,8 +51,16 @@ SettingsEditor::SettingsEditor(Manager &manager, update::Loader &updater)
     ui->proxyPassEdit->setEchoMode(QLineEdit::PasswordEchoOnEdit);
   }
 
-  // translation
+  // recognition
   ui->tesseractLangCombo->setModel(models_.sourceLanguageModel());
+  const QMap<TesseractVersion, QString> tesseractVersions{
+      {TesseractVersion::Optimized, tr("Optimized")},
+      {TesseractVersion::Compatible, tr("Compatible")},
+  };
+  ui->tesseractVersion->addItems(tesseractVersions.values());
+  ui->tesseractVersion->setToolTip(
+      tr("Use compatible version if you are experiencing crashes during "
+         "recognition"));
 
   // correction
   ui->userSubstitutionsTable->setEnabled(ui->useUserSubstitutions->isChecked());
@@ -164,6 +172,8 @@ Settings SettingsEditor::settings() const
 
   settings.sourceLanguage =
       LanguageCodes::idForName(ui->tesseractLangCombo->currentText());
+  settings.tesseractVersion =
+      TesseractVersion(ui->tesseractVersion->currentIndex());
 
   settings.useHunspell = ui->useHunspell->isChecked();
   settings.useUserSubstitutions = ui->useUserSubstitutions->isChecked();
@@ -227,6 +237,7 @@ void SettingsEditor::setSettings(const Settings &settings)
   ui->tessdataPath->setText(settings.tessdataPath);
   ui->tesseractLangCombo->setCurrentText(
       LanguageCodes::name(settings.sourceLanguage));
+  ui->tesseractVersion->setCurrentIndex(int(settings.tesseractVersion));
 
   ui->useHunspell->setChecked(settings.useHunspell);
   ui->hunspellDir->setText(settings.hunspellDir);

src/settingseditor.ui

@@ -227,19 +227,29 @@
      </widget>
      <widget class="QWidget" name="pageRecognize">
       <layout class="QGridLayout" name="gridLayout_2">
-       <item row="1" column="0">
+       <item row="3" column="2">
-        <widget class="QLabel" name="label_4">
+        <spacer name="verticalSpacer_2">
-         <property name="sizePolicy">
+         <property name="orientation">
-          <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
+          <enum>Qt::Vertical</enum>
-           <horstretch>0</horstretch>
-           <verstretch>0</verstretch>
-          </sizepolicy>
          </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>17</width>
+           <height>410</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+       <item row="0" column="2">
+        <widget class="QLabel" name="tessdataPath">
          <property name="text">
-          <string>Default language:</string>
+          <string/>
          </property>
-         <property name="buddy">
+         <property name="wordWrap">
-          <cstring>tesseractLangCombo</cstring>
+          <bool>true</bool>
+         </property>
+         <property name="textInteractionFlags">
+          <set>Qt::LinksAccessibleByMouse|Qt::TextSelectableByMouse</set>
          </property>
         </widget>
        </item>
@@ -256,35 +266,35 @@
          </property>
         </widget>
        </item>
-       <item row="2" column="2">
+       <item row="1" column="0">
-        <spacer name="verticalSpacer_2">
+        <widget class="QLabel" name="label_4">
-         <property name="orientation">
+         <property name="sizePolicy">
-          <enum>Qt::Vertical</enum>
+          <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
          </property>
-         <property name="sizeHint" stdset="0">
+         <property name="text">
-          <size>
+          <string>Default language:</string>
-           <width>17</width>
-           <height>410</height>
-          </size>
          </property>
-        </spacer>
+         <property name="buddy">
+          <cstring>tesseractLangCombo</cstring>
+         </property>
+        </widget>
        </item>
        <item row="1" column="2">
         <widget class="QComboBox" name="tesseractLangCombo"/>
        </item>
-       <item row="0" column="2">
+       <item row="2" column="0">
-        <widget class="QLabel" name="tessdataPath">
+        <widget class="QLabel" name="label_24">
          <property name="text">
-          <string/>
+          <string>Library version</string>
-         </property>
-         <property name="wordWrap">
-          <bool>true</bool>
-         </property>
-         <property name="textInteractionFlags">
-          <set>Qt::LinksAccessibleByMouse|Qt::TextSelectableByMouse</set>
          </property>
         </widget>
        </item>
+       <item row="2" column="2">
+        <widget class="QComboBox" name="tesseractVersion"/>
+       </item>
       </layout>
      </widget>
      <widget class="QWidget" name="pageCorrect">