tesseract/ccutil/ocrclass.h

162 lines
7.5 KiB
C++

/**********************************************************************
* File: ocrclass.h
* Description: Class definitions and constants for the OCR API.
* Author: Hewlett-Packard Co
*
* (C) Copyright 1996, Hewlett-Packard Co.
** 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.
*
**********************************************************************/
/**********************************************************************
* This file contains typedefs for all the structures used by
* the HP OCR interface.
* The code is designed to be used with either a C or C++ compiler.
* The structures are designed to allow them to be used with any
* structure alignment up to 8.
**********************************************************************/
#ifndef CCUTIL_OCRCLASS_H_
#define CCUTIL_OCRCLASS_H_
#ifndef __GNUC__
#ifdef _WIN32
#include <windows.h>
#include "gettimeofday.h"
#endif
#else
#include <sys/time.h>
#endif
#include <time.h>
#include "host.h"
/*Maximum lengths of various strings*/
#define MAX_FONT_NAME 34 /*name of font */
#define MAX_OCR_NAME 32 /*name of engine */
#define MAX_OCR_VERSION 17 /*version code of engine */
/*pitch set definitions are identical to RTF*/
#define PITCH_DEF 0 /*default */
#define PITCH_FIXED 1 /*fixed pitch */
#define PITCH_VAR 2 /*variable pitch */
/**********************************************************************
* EANYCODE_CHAR
* Description of a single character. The character code is defined by
* the character set of the current font.
* Output text is sent as an array of these structures.
* Spaces and line endings in the output are represented in the
* structures of the surrounding characters. They are not directly
* represented as characters.
* The first character in a word has a positive value of blanks.
* Missing information should be set to the defaults in the comments.
* If word bounds are known, but not character bounds, then the top and
* bottom of each character should be those of the word. The left of the
* first and right of the last char in each word should be set. All other
* lefts and rights should be set to -1.
* If set, the values of right and bottom are left+width and top+height.
* Most of the members come directly from the parameters to ocr_append_char.
* The formatting member uses the enhancement parameter and combines the
* line direction stuff into the top 3 bits.
* The coding is 0=RL char, 1=LR char, 2=DR NL, 3=UL NL, 4=DR Para,
* 5=UL Para, 6=TB char, 7=BT char. API users do not need to know what
* the coding is, only that it is backwards compatible with the previous
* version.
**********************************************************************/
typedef struct { /*single character */
// It should be noted that the format for char_code for version 2.0 and beyond
// is UTF8 which means that ASCII characters will come out as one structure but
// other characters will be returned in two or more instances of this structure
// with a single byte of the UTF8 code in each, but each will have the same
// bounding box. Programs which want to handle languagues with different
// characters sets will need to handle extended characters appropriately, but
// *all* code needs to be prepared to receive UTF8 coded characters for
// characters such as bullet and fancy quotes.
uinT16 char_code; /*character itself */
inT16 left; /*of char (-1) */
inT16 right; /*of char (-1) */
inT16 top; /*of char (-1) */
inT16 bottom; /*of char (-1) */
inT16 font_index; /*what font (0) */
uinT8 confidence; /*0=perfect, 100=reject (0/100) */
uinT8 point_size; /*of char, 72=i inch, (10) */
inT8 blanks; /*no of spaces before this char (1) */
uinT8 formatting; /*char formatting (0) */
} EANYCODE_CHAR; /*single character */
/**********************************************************************
* ETEXT_DESC
* Description of the output of the OCR engine.
* This structure is used as both a progress monitor and the final
* output header, since it needs to be a valid progress monitor while
* the OCR engine is storing its output to shared memory.
* During progress, all the buffer info is -1.
* Progress starts at 0 and increases to 100 during OCR. No other constraint.
* Additionally the progress callback contains the bounding box of the word that
* is currently being processed.
* Every progress callback, the OCR engine must set ocr_alive to 1.
* The HP side will set ocr_alive to 0. Repeated failure to reset
* to 1 indicates that the OCR engine is dead.
* If the cancel function is not null then it is called with the number of
* user words found. If it returns true then operation is cancelled.
**********************************************************************/
typedef bool (*CANCEL_FUNC)(void* cancel_this, int words);
typedef bool (*PROGRESS_FUNC)(int progress,
int left, int right, int top, int bottom);
class ETEXT_DESC { // output header
public:
inT16 count; /// chars in this buffer(0)
inT16 progress; /// percent complete increasing (0-100)
/** Progress monitor covers word recognition and it does not cover layout
* analysis.
* See Ray comment in https://github.com/tesseract-ocr/tesseract/pull/27 */
inT8 more_to_come; /// true if not last
volatile inT8 ocr_alive; /// ocr sets to 1, HP 0
inT8 err_code; /// for errcode use
CANCEL_FUNC cancel; /// returns true to cancel
PROGRESS_FUNC progress_callback; /// called whenever progress increases
void* cancel_this; /// this or other data for cancel
struct timeval end_time; /** time to stop. expected to be set only by call
* to set_deadline_msecs() */
EANYCODE_CHAR text[1]; /// character data
ETEXT_DESC() : count(0), progress(0), more_to_come(0), ocr_alive(0),
err_code(0), cancel(NULL), cancel_this(NULL) {
end_time.tv_sec = 0;
end_time.tv_usec = 0;
}
// Sets the end time to be deadline_msecs milliseconds from now.
void set_deadline_msecs(inT32 deadline_msecs) {
gettimeofday(&end_time, NULL);
inT32 deadline_secs = deadline_msecs / 1000;
end_time.tv_sec += deadline_secs;
end_time.tv_usec += (deadline_msecs - deadline_secs * 1000) * 1000;
if (end_time.tv_usec > 1000000) {
end_time.tv_usec -= 1000000;
++end_time.tv_sec;
}
}
// Returns false if we've not passed the end_time, or have not set a deadline.
bool deadline_exceeded() const {
if (end_time.tv_sec == 0 && end_time.tv_usec == 0) return false;
struct timeval now;
gettimeofday(&now, NULL);
return (now.tv_sec > end_time.tv_sec || (now.tv_sec == end_time.tv_sec &&
now.tv_usec > end_time.tv_usec));
}
};
#endif // CCUTIL_OCRCLASS_H_