tesseract/ccstruct/publictypes.h

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///////////////////////////////////////////////////////////////////////
// File: publictypes.h
// Description: Types used in both the API and internally
// Author: Ray Smith
// Created: Wed Mar 03 09:22:53 PST 2010
//
// (C) Copyright 2010, Google Inc.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
///////////////////////////////////////////////////////////////////////
#ifndef TESSERACT_CCSTRUCT_PUBLICTYPES_H_
#define TESSERACT_CCSTRUCT_PUBLICTYPES_H_
// This file contains types that are used both by the API and internally
// to Tesseract. In order to decouple the API from Tesseract and prevent cyclic
// dependencies, THIS FILE SHOULD NOT DEPEND ON ANY OTHER PART OF TESSERACT.
// Restated: It is OK for low-level Tesseract files to include publictypes.h,
// but not for the low-level tesseract code to include top-level API code.
// This file should not use other Tesseract types, as that would drag
// their includes into the API-level.
// API-level code should include apitypes.h in preference to this file.
/** Number of printers' points in an inch. The unit of the pointsize return. */
constexpr int kPointsPerInch = 72;
/**
* Minimum believable resolution. Used as a default if there is no other
* information, as it is safer to under-estimate than over-estimate.
*/
constexpr int kMinCredibleResolution = 70;
/** Maximum believable resolution. */
constexpr int kMaxCredibleResolution = 2400;
/**
* Ratio between median blob size and likely resolution. Used to estimate
* resolution when none is provided. This is basically 1/usual text size in
* inches. */
constexpr int kResolutionEstimationFactor = 10;
/**
* Possible types for a POLY_BLOCK or ColPartition.
* Must be kept in sync with kPBColors in polyblk.cpp and PTIs*Type functions
* below, as well as kPolyBlockNames in publictypes.cpp.
* Used extensively by ColPartition, and POLY_BLOCK.
*/
enum PolyBlockType {
PT_UNKNOWN, // Type is not yet known. Keep as the first element.
PT_FLOWING_TEXT, // Text that lives inside a column.
PT_HEADING_TEXT, // Text that spans more than one column.
PT_PULLOUT_TEXT, // Text that is in a cross-column pull-out region.
PT_EQUATION, // Partition belonging to an equation region.
PT_INLINE_EQUATION, // Partition has inline equation.
PT_TABLE, // Partition belonging to a table region.
PT_VERTICAL_TEXT, // Text-line runs vertically.
PT_CAPTION_TEXT, // Text that belongs to an image.
PT_FLOWING_IMAGE, // Image that lives inside a column.
PT_HEADING_IMAGE, // Image that spans more than one column.
PT_PULLOUT_IMAGE, // Image that is in a cross-column pull-out region.
PT_HORZ_LINE, // Horizontal Line.
PT_VERT_LINE, // Vertical Line.
PT_NOISE, // Lies outside of any column.
PT_COUNT
};
/** Returns true if PolyBlockType is of horizontal line type */
inline bool PTIsLineType(PolyBlockType type) {
return type == PT_HORZ_LINE || type == PT_VERT_LINE;
}
/** Returns true if PolyBlockType is of image type */
inline bool PTIsImageType(PolyBlockType type) {
return type == PT_FLOWING_IMAGE || type == PT_HEADING_IMAGE ||
type == PT_PULLOUT_IMAGE;
}
/** Returns true if PolyBlockType is of text type */
inline bool PTIsTextType(PolyBlockType type) {
return type == PT_FLOWING_TEXT || type == PT_HEADING_TEXT ||
type == PT_PULLOUT_TEXT || type == PT_TABLE ||
type == PT_VERTICAL_TEXT || type == PT_CAPTION_TEXT ||
type == PT_INLINE_EQUATION;
}
// Returns true if PolyBlockType is of pullout(inter-column) type
inline bool PTIsPulloutType(PolyBlockType type) {
return type == PT_PULLOUT_IMAGE || type == PT_PULLOUT_TEXT;
}
/** String name for each block type. Keep in sync with PolyBlockType. */
extern const char* kPolyBlockNames[];
namespace tesseract {
/**
* +------------------+ Orientation Example:
* | 1 Aaaa Aaaa Aaaa | ====================
* | Aaa aa aaa aa | To left is a diagram of some (1) English and
* | aaaaaa A aa aaa. | (2) Chinese text and a (3) photo credit.
* | 2 |
* | ####### c c C | Upright Latin characters are represented as A and a.
* | ####### c c c | '<' represents a latin character rotated
* | < ####### c c c | anti-clockwise 90 degrees.
* | < ####### c c |
* | < ####### . c | Upright Chinese characters are represented C and c.
* | 3 ####### c |
* +------------------+ NOTA BENE: enum values here should match goodoc.proto
* If you orient your head so that "up" aligns with Orientation,
* then the characters will appear "right side up" and readable.
*
* In the example above, both the English and Chinese paragraphs are oriented
* so their "up" is the top of the page (page up). The photo credit is read
* with one's head turned leftward ("up" is to page left).
*
* The values of this enum match the convention of Tesseract's osdetect.h
*/
enum Orientation {
ORIENTATION_PAGE_UP = 0,
ORIENTATION_PAGE_RIGHT = 1,
ORIENTATION_PAGE_DOWN = 2,
ORIENTATION_PAGE_LEFT = 3,
};
/**
* The grapheme clusters within a line of text are laid out logically
* in this direction, judged when looking at the text line rotated so that
* its Orientation is "page up".
*
* For English text, the writing direction is left-to-right. For the
* Chinese text in the above example, the writing direction is top-to-bottom.
*/
enum WritingDirection {
WRITING_DIRECTION_LEFT_TO_RIGHT = 0,
WRITING_DIRECTION_RIGHT_TO_LEFT = 1,
WRITING_DIRECTION_TOP_TO_BOTTOM = 2,
};
/**
* The text lines are read in the given sequence.
*
* In English, the order is top-to-bottom.
* In Chinese, vertical text lines are read right-to-left. Mongolian is
* written in vertical columns top to bottom like Chinese, but the lines
* order left-to right.
*
* Note that only some combinations make sense. For example,
* WRITING_DIRECTION_LEFT_TO_RIGHT implies TEXTLINE_ORDER_TOP_TO_BOTTOM
*/
enum TextlineOrder {
TEXTLINE_ORDER_LEFT_TO_RIGHT = 0,
TEXTLINE_ORDER_RIGHT_TO_LEFT = 1,
TEXTLINE_ORDER_TOP_TO_BOTTOM = 2,
};
/**
* Possible modes for page layout analysis. These *must* be kept in order
* of decreasing amount of layout analysis to be done, except for OSD_ONLY,
* so that the inequality test macros below work.
*/
enum PageSegMode {
PSM_OSD_ONLY, ///< Orientation and script detection only.
PSM_AUTO_OSD, ///< Automatic page segmentation with orientation and
///< script detection. (OSD)
PSM_AUTO_ONLY, ///< Automatic page segmentation, but no OSD, or OCR.
PSM_AUTO, ///< Fully automatic page segmentation, but no OSD.
PSM_SINGLE_COLUMN, ///< Assume a single column of text of variable sizes.
PSM_SINGLE_BLOCK_VERT_TEXT, ///< Assume a single uniform block of vertically
///< aligned text.
PSM_SINGLE_BLOCK, ///< Assume a single uniform block of text. (Default.)
PSM_SINGLE_LINE, ///< Treat the image as a single text line.
PSM_SINGLE_WORD, ///< Treat the image as a single word.
PSM_CIRCLE_WORD, ///< Treat the image as a single word in a circle.
PSM_SINGLE_CHAR, ///< Treat the image as a single character.
PSM_SPARSE_TEXT, ///< Find as much text as possible in no particular order.
PSM_SPARSE_TEXT_OSD, ///< Sparse text with orientation and script det.
PSM_RAW_LINE, ///< Treat the image as a single text line, bypassing
///< hacks that are Tesseract-specific.
PSM_COUNT ///< Number of enum entries.
};
/**
* Inline functions that act on a PageSegMode to determine whether components of
* layout analysis are enabled.
* *Depend critically on the order of elements of PageSegMode.*
* NOTE that arg is an int for compatibility with INT_PARAM.
*/
inline bool PSM_OSD_ENABLED(int pageseg_mode) {
return pageseg_mode <= PSM_AUTO_OSD || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
inline bool PSM_ORIENTATION_ENABLED(int pageseg_mode) {
return pageseg_mode <= PSM_AUTO || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
inline bool PSM_COL_FIND_ENABLED(int pageseg_mode) {
return pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_AUTO;
}
inline bool PSM_SPARSE(int pageseg_mode) {
return pageseg_mode == PSM_SPARSE_TEXT || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
inline bool PSM_BLOCK_FIND_ENABLED(int pageseg_mode) {
return pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_SINGLE_COLUMN;
}
inline bool PSM_LINE_FIND_ENABLED(int pageseg_mode) {
return pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_SINGLE_BLOCK;
}
inline bool PSM_WORD_FIND_ENABLED(int pageseg_mode) {
return (pageseg_mode >= PSM_AUTO_OSD && pageseg_mode <= PSM_SINGLE_LINE) ||
pageseg_mode == PSM_SPARSE_TEXT || pageseg_mode == PSM_SPARSE_TEXT_OSD;
}
/**
* enum of the elements of the page hierarchy, used in ResultIterator
* to provide functions that operate on each level without having to
* have 5x as many functions.
*/
enum PageIteratorLevel {
RIL_BLOCK, // Block of text/image/separator line.
RIL_PARA, // Paragraph within a block.
RIL_TEXTLINE, // Line within a paragraph.
RIL_WORD, // Word within a textline.
RIL_SYMBOL // Symbol/character within a word.
};
/**
2017-04-14 22:54:10 +08:00
* JUSTIFICATION_UNKNOWN
* The alignment is not clearly one of the other options. This could happen
* for example if there are only one or two lines of text or the text looks
* like source code or poetry.
*
* NOTA BENE: Fully justified paragraphs (text aligned to both left and right
* margins) are marked by Tesseract with JUSTIFICATION_LEFT if their text
* is written with a left-to-right script and with JUSTIFICATION_RIGHT if
* their text is written in a right-to-left script.
*
* Interpretation for text read in vertical lines:
* "Left" is wherever the starting reading position is.
*
* JUSTIFICATION_LEFT
* Each line, except possibly the first, is flush to the same left tab stop.
*
* JUSTIFICATION_CENTER
* The text lines of the paragraph are centered about a line going
* down through their middle of the text lines.
*
* JUSTIFICATION_RIGHT
* Each line, except possibly the first, is flush to the same right tab stop.
2017-04-29 04:38:32 +08:00
*/
enum ParagraphJustification {
JUSTIFICATION_UNKNOWN,
JUSTIFICATION_LEFT,
JUSTIFICATION_CENTER,
JUSTIFICATION_RIGHT,
};
/**
* When Tesseract/Cube is initialized we can choose to instantiate/load/run
* only the Tesseract part, only the Cube part or both along with the combiner.
* The preference of which engine to use is stored in tessedit_ocr_engine_mode.
*
* ATTENTION: When modifying this enum, please make sure to make the
* appropriate changes to all the enums mirroring it (e.g. OCREngine in
* cityblock/workflow/detection/detection_storage.proto). Such enums will
* mention the connection to OcrEngineMode in the comments.
*/
enum OcrEngineMode {
OEM_TESSERACT_ONLY, // Run Tesseract only - fastest
OEM_LSTM_ONLY, // Run just the LSTM line recognizer.
OEM_TESSERACT_LSTM_COMBINED, // Run the LSTM recognizer, but allow fallback
// to Tesseract when things get difficult.
OEM_DEFAULT, // Specify this mode when calling init_*(),
// to indicate that any of the above modes
// should be automatically inferred from the
// variables in the language-specific config,
// command-line configs, or if not specified
// in any of the above should be set to the
// default OEM_TESSERACT_ONLY.
OEM_CUBE_ONLY, // Run Cube only - better accuracy, but slower
OEM_TESSERACT_CUBE_COMBINED, // Run both and combine results - best accuracy
};
} // namespace tesseract.
#endif // TESSERACT_CCSTRUCT_PUBLICTYPES_H_