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166c867d84
git-svn-id: https://tesseract-ocr.googlecode.com/svn/trunk@129 d0cd1f9f-072b-0410-8dd7-cf729c803f20
1088 lines
35 KiB
C++
1088 lines
35 KiB
C++
/******************************************************************************
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** Filename: mfoutline.c
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** Purpose: Interface to outline struct used for extracting features
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** Author: Dan Johnson
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** History: Thu May 17 08:14:18 1990, DSJ, Created.
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**
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** (c) Copyright Hewlett-Packard Company, 1988.
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** Licensed under the Apache License, Version 2.0 (the "License");
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** you may not use this file except in compliance with the License.
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** You may obtain a copy of the License at
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** http://www.apache.org/licenses/LICENSE-2.0
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** Unless required by applicable law or agreed to in writing, software
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** distributed under the License is distributed on an "AS IS" BASIS,
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** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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** See the License for the specific language governing permissions and
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** limitations under the License.
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******************************************************************************/
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/**----------------------------------------------------------------------------
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Include Files and Type Defines
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----------------------------------------------------------------------------**/
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#include "clusttool.h" //If remove you get cought in a loop somewhere
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#include "emalloc.h"
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#include "mfoutline.h"
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#include "debug.h"
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#include "hideedge.h"
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#include "blobs.h"
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#include "const.h"
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#include "mfx.h"
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#include <math.h>
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#include <stdio.h>
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#define MIN_INERTIA (0.00001)
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/**----------------------------------------------------------------------------
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Private Function Prototypes
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----------------------------------------------------------------------------**/
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/*
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#if defined(__STDC__) || defined(__cplusplus)
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# define _ARGS(s) s
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#else
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# define _ARGS(s) ()
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#endif*/
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/* /users/danj/wiseowl/src/danj/microfeatures/mfoutline.c
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void ChangeDirection
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_ARGS((MFOUTLINE Start,
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MFOUTLINE End,
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DIRECTION Direction));
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void CharNormalizeOutline
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_ARGS((MFOUTLINE Outline,
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OUTLINE_STATS *OutlineStats));
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void ComputeDirection
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_ARGS((MFEDGEPT *Start,
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MFEDGEPT *Finish,
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FLOAT32 MinSlope,
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FLOAT32 MaxSlope));
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void FinishOutlineStats
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_ARGS((OUTLINE_STATS *OutlineStats));
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void InitOutlineStats
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_ARGS((OUTLINE_STATS *OutlineStats));
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MFOUTLINE NextDirectionChange
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_ARGS((MFOUTLINE EdgePoint));
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void UpdateOutlineStats
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_ARGS((OUTLINE_STATS *OutlineStats,
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FLOAT32 x1,
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FLOAT32 y1,
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FLOAT32 x2,
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FLOAT32 y2));
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#undef _ARGS
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*/
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/**----------------------------------------------------------------------------
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Global Data Definitions and Declarations
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----------------------------------------------------------------------------**/
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/* center of current blob being processed - used when "unexpanding"
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expanded blobs */
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static TPOINT BlobCenter;
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/* control knobs used to control normalization of outlines */
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make_int_var (NormMethod, character, MakeNormMethod,
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15, 10, SetNormMethod, "Normalization Method ...")
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/* PREV DEFAULT "baseline" */
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make_float_var (CharNormRange, 0.2, MakeCharNormRange,
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15, 11, SetCharNormRange, "Character Normalization Range ...")
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make_float_var (MinNormScaleX, 0.0, MakeMinNormScaleX,
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15, 12, SetMinNormScaleX, "Min char x-norm scale ...")
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/* PREV DEFAULT 0.1 */
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make_float_var (MaxNormScaleX, 0.325, MakeMaxNormScaleX,
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15, 13, SetMaxNormScaleX, "Max char x-norm scale ...")
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/* PREV DEFAULT 0.3 */
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make_float_var (MinNormScaleY, 0.0, MakeMinNormScaleY,
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15, 14, SetMinNormScaleY, "Min char y-norm scale ...")
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/* PREV DEFAULT 0.1 */
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make_float_var (MaxNormScaleY, 0.325, MakeMaxNormScaleY,
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15, 15, SetMaxNormScaleY, "Max char y-norm scale ...")
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/* PREV DEFAULT 0.3 */
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/**----------------------------------------------------------------------------
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Public Code
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----------------------------------------------------------------------------**/
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/*---------------------------------------------------------------------------*/
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void ComputeBlobCenter(TBLOB *Blob, TPOINT *BlobCenter) {
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/*
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** Parameters:
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** Blob blob to compute centerpoint of
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** BlobCenter data struct to place results in
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** Globals: none
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** Operation:
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** This routine computes the center point of the specified
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** blob using the bounding box of all top level outlines in the
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** blob. The center point is computed in a coordinate system
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** which is scaled up by VECSCALE from the page coordinate
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** system.
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** Return: none
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** Exceptions: none
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** History: Fri Sep 8 10:45:39 1989, DSJ, Created.
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*/
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TPOINT TopLeft;
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TPOINT BottomRight;
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blob_bounding_box(Blob, &TopLeft, &BottomRight);
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BlobCenter->x = ((TopLeft.x << VECSCALE) + (BottomRight.x << VECSCALE)) / 2;
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BlobCenter->y = ((TopLeft.y << VECSCALE) + (BottomRight.y << VECSCALE)) / 2;
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} /* ComputeBlobCenter */
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/*---------------------------------------------------------------------------*/
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LIST ConvertBlob(TBLOB *Blob) {
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/*
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** Parameters:
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** Blob blob to be converted
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** Globals: none
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** Operation: Convert Blob into a list of outlines.
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** Return: List of outlines representing blob.
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** Exceptions: none
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** History: Thu Dec 13 15:40:17 1990, DSJ, Created.
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*/
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LIST ConvertedOutlines = NIL;
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if (Blob != NULL) {
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SettupBlobConversion(Blob); //ComputeBlobCenter (Blob, &BlobCenter);
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ConvertedOutlines = ConvertOutlines (Blob->outlines,
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ConvertedOutlines, outer);
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}
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return (ConvertedOutlines);
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} /* ConvertBlob */
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/*---------------------------------------------------------------------------*/
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MFOUTLINE ConvertOutline(TESSLINE *Outline) {
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/*
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** Parameters:
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** Outline outline to be converted
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** Globals:
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** BlobCenter pre-computed center of current blob
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** Operation:
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** This routine converts the specified outline into a special
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** data structure which is used for extracting micro-features.
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** If the outline has been pre-normalized by the splitter,
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** then it is assumed to be in expanded form and all we must
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** do is copy the points. Otherwise,
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** if the outline is expanded, then the expanded form is used
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** and the coordinates of the points are returned to page
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** coordinates using the global variable BlobCenter and the
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** scaling factor REALSCALE. If the outline is not expanded,
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** then the compressed form is used.
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** Return: Outline converted into special micro-features format.
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** Exceptions: none
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** History: 8/2/89, DSJ, Created.
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** 9/8/89, DSJ, Added ability to convert expanded blobs.
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** 1/11/90, DSJ, Changed to use REALSCALE instead of VECSCALE
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** to eliminate round-off problems.
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** 2/21/91, DSJ, Added ability to work with pre-normalized
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** blobs.
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** 4/30/91, DSJ, Added concept of "hidden" segments.
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*/
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register BYTEVEC *Vector;
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TPOINT Position;
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TPOINT StartPosition;
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MFEDGEPT *NewPoint;
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MFOUTLINE MFOutline = NIL;
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EDGEPT *EdgePoint;
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EDGEPT *StartPoint;
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EDGEPT *NextPoint;
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if (Outline == NULL ||
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(Outline->compactloop == NULL && Outline->loop == NULL))
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return (MFOutline);
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/* have outlines been prenormalized */
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if (is_baseline_normalized ()) {
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StartPoint = Outline->loop;
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EdgePoint = StartPoint;
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do {
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NextPoint = EdgePoint->next;
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/* filter out duplicate points */
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if (EdgePoint->pos.x != NextPoint->pos.x ||
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EdgePoint->pos.y != NextPoint->pos.y) {
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NewPoint = NewEdgePoint ();
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ClearMark(NewPoint);
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IsHidden (NewPoint) = is_hidden_edge (EdgePoint) ? TRUE : FALSE;
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XPositionOf (NewPoint) = EdgePoint->pos.x;
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YPositionOf (NewPoint) = EdgePoint->pos.y;
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MFOutline = push (MFOutline, NewPoint);
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}
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EdgePoint = NextPoint;
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}
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while (EdgePoint != StartPoint);
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}
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/* use compressed version of outline */
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else if (Outline->loop == NULL) {
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Xof (Position) = Xof (StartPosition) = Outline->start.x;
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Yof (Position) = Yof (StartPosition) = Outline->start.y;
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Vector = Outline->compactloop;
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do {
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if (Vector->dx != 0 || Vector->dy != 0) {
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NewPoint = NewEdgePoint ();
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ClearMark(NewPoint);
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/* all edges are visible */
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IsHidden (NewPoint) = FALSE;
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CopyPoint (Position, PositionOf (NewPoint));
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MFOutline = push (MFOutline, NewPoint);
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}
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Xof (Position) += Vector->dx;
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Yof (Position) += Vector->dy;
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Vector++;
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}
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while ((Xof (Position) != Xof (StartPosition)) ||
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(Yof (Position) != Yof (StartPosition)));
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}
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else { /* use expanded version of outline */
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StartPoint = Outline->loop;
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EdgePoint = StartPoint;
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do {
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NextPoint = EdgePoint->next;
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/* filter out duplicate points */
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if (EdgePoint->pos.x != NextPoint->pos.x ||
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EdgePoint->pos.y != NextPoint->pos.y) {
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NewPoint = NewEdgePoint ();
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ClearMark(NewPoint);
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IsHidden (NewPoint) = is_hidden_edge (EdgePoint) ? TRUE : FALSE;
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XPositionOf (NewPoint) =
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(EdgePoint->pos.x + BlobCenter.x) / REALSCALE;
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YPositionOf (NewPoint) =
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(EdgePoint->pos.y + BlobCenter.y) / REALSCALE;
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MFOutline = push (MFOutline, NewPoint);
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}
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EdgePoint = NextPoint;
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}
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while (EdgePoint != StartPoint);
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}
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MakeOutlineCircular(MFOutline);
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return (MFOutline);
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} /* ConvertOutline */
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/*---------------------------------------------------------------------------*/
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LIST ConvertOutlines(TESSLINE *Outline,
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LIST ConvertedOutlines,
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OUTLINETYPE OutlineType) {
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/*
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** Parameters:
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** Outline first outline to be converted
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** ConvertedOutlines list to add converted outlines to
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** OutlineType are the outlines outer or holes?
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** Globals: none
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** Operation:
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** This routine converts all given outlines into a new format.
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** of outlines. Outline points to a list of the top level
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** outlines to be converted. The children of these outlines
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** are also recursively converted. All converted outlines
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** are added to ConvertedOutlines. This is a list of outlines,
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** one for each outline that was converted.
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** Return: Updated list of converted outlines.
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** Exceptions: none
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** History: Thu Dec 13 15:57:38 1990, DSJ, Created.
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*/
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MFOUTLINE MFOutline;
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while (Outline != NULL) {
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if (Outline->child != NULL) {
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if (OutlineType == outer)
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ConvertedOutlines = ConvertOutlines (Outline->child,
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ConvertedOutlines, hole);
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else
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ConvertedOutlines = ConvertOutlines (Outline->child,
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ConvertedOutlines, outer);
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}
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MFOutline = ConvertOutline (Outline);
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ConvertedOutlines = push (ConvertedOutlines, MFOutline);
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Outline = Outline->next;
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}
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return (ConvertedOutlines);
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} /* ConvertOutlines */
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/*---------------------------------------------------------------------------*/
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void ComputeOutlineStats(LIST Outlines, OUTLINE_STATS *OutlineStats) {
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/*
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** Parameters:
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** Outlines list of outlines to compute stats for
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** OutlineStats place to put results
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** Globals: none
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** Operation: This routine computes several statistics about the outlines
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** in Outlines. These statistics are usually used to perform
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** anistropic normalization of all of the outlines. The
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** statistics generated are:
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** first moments about x and y axes
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** total length of all outlines
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** center of mass of all outlines
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** second moments about center of mass axes
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** radius of gyration about center of mass axes
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** Return: none (results are returned in OutlineStats)
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** Exceptions: none
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** History: Fri Dec 14 08:32:03 1990, DSJ, Created.
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*/
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MFOUTLINE Outline;
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MFOUTLINE EdgePoint;
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MFEDGEPT *Current;
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MFEDGEPT *Last;
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InitOutlineStats(OutlineStats);
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iterate(Outlines) {
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Outline = (MFOUTLINE) first_node (Outlines);
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Last = PointAt (Outline);
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Outline = NextPointAfter (Outline);
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EdgePoint = Outline;
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do {
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Current = PointAt (EdgePoint);
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UpdateOutlineStats (OutlineStats,
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XPositionOf (Last), YPositionOf (Last),
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XPositionOf (Current), YPositionOf (Current));
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Last = Current;
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EdgePoint = NextPointAfter (EdgePoint);
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}
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while (EdgePoint != Outline);
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}
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FinishOutlineStats(OutlineStats);
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} /* ComputeOutlineStats */
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/*---------------------------------------------------------------------------*/
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void FilterEdgeNoise(MFOUTLINE Outline, FLOAT32 NoiseSegmentLength) {
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/*
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** Parameters:
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** Outline outline to be filtered
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** NoiseSegmentLength maximum length of a "noise" segment
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** Globals: none
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** Operation: Filter out noise from the specified outline. This is
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** done by changing the direction of short segments of the
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** outline to the same direction as the preceding outline
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** segment.
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** Return: none
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** Exceptions: none
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** History: Fri May 4 10:23:45 1990, DSJ, Created.
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*/
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MFOUTLINE Current;
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MFOUTLINE Last;
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MFOUTLINE First;
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FLOAT32 Length;
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int NumFound = 0;
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DIRECTION DirectionOfFirst = north;
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if (DegenerateOutline (Outline))
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return;
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/* find 2 segments of different orientation which are long enough to
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not be filtered. If two cannot be found, leave the outline unchanged. */
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First = NextDirectionChange (Outline);
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Last = First;
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do {
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Current = NextDirectionChange (Last);
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Length = DistanceBetween (PositionOf (PointAt (Current)),
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PositionOf (PointAt (Last)));
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if (Length >= NoiseSegmentLength) {
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if (NumFound == 0) {
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NumFound = 1;
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DirectionOfFirst = DirectionOf (PointAt (Last));
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}
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else if (DirectionOfFirst != DirectionOf (PointAt (Last)))
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break;
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}
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Last = Current;
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}
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while (Last != First);
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if (Current == Last)
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return;
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/* find each segment and filter it out if it is too short. Note that
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the above code guarantees that the initial direction change will
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not be removed, therefore the loop will terminate. */
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First = Last;
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do {
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Current = NextDirectionChange (Last);
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Length = DistanceBetween (PositionOf (PointAt (Current)),
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PositionOf (PointAt (Last)));
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if (Length < NoiseSegmentLength)
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ChangeDirection (Last, Current, PreviousDirectionOf (PointAt (Last)));
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Last = Current;
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}
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while (Last != First);
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} /* FilterEdgeNoise */
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/*---------------------------------------------------------------------------*/
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void FindDirectionChanges(MFOUTLINE Outline,
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FLOAT32 MinSlope,
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FLOAT32 MaxSlope) {
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/*
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** Parameters:
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** Outline micro-feature outline to analyze
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** MinSlope controls "snapping" of segments to horizontal
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** MaxSlope controls "snapping" of segments to vertical
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** Globals: none
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** Operation:
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** This routine searches thru the specified outline, computes
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** a slope for each vector in the outline, and marks each
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** vector as having one of the following directions:
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** N, S, E, W, NE, NW, SE, SW
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** This information is then stored in the outline and the
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** outline is returned.
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** Return: none
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** Exceptions: none
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** History: 7/21/89, DSJ, Created.
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*/
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MFEDGEPT *Current;
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MFEDGEPT *Last;
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MFOUTLINE EdgePoint;
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if (DegenerateOutline (Outline))
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return;
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Last = PointAt (Outline);
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Outline = NextPointAfter (Outline);
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EdgePoint = Outline;
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do {
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Current = PointAt (EdgePoint);
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ComputeDirection(Last, Current, MinSlope, MaxSlope);
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Last = Current;
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EdgePoint = NextPointAfter (EdgePoint);
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}
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while (EdgePoint != Outline);
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} /* FindDirectionChanges */
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/*---------------------------------------------------------------------------*/
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void FreeMFOutline(void *arg) { //MFOUTLINE Outline)
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/*
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** Parameters:
|
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** Outline micro-feature outline to be freed
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** Globals: none
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** Operation:
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** This routine deallocates all of the memory consumed by
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** a micro-feature outline.
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** Return: none
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** Exceptions: none
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** History: 7/27/89, DSJ, Created.
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*/
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MFOUTLINE Start;
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MFOUTLINE Outline = (MFOUTLINE) arg;
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/* break the circular outline so we can use std. techniques to deallocate */
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Start = rest (Outline);
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set_rest(Outline, NIL);
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while (Start != NULL) {
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c_free_struct (first_node (Start), sizeof (MFEDGEPT), "MFEDGEPT");
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Start = pop (Start);
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}
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|
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} /* FreeMFOutline */
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|
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/*---------------------------------------------------------------------------*/
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void FreeOutlines(LIST Outlines) {
|
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/*
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** Parameters:
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** Outlines list of mf-outlines to be freed
|
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** Globals: none
|
|
** Operation: Release all memory consumed by the specified list
|
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** of outlines.
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** Return: none
|
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** Exceptions: none
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** History: Thu Dec 13 16:14:50 1990, DSJ, Created.
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|
*/
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destroy_nodes(Outlines, FreeMFOutline);
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} /* FreeOutlines */
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|
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|
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/*---------------------------------------------------------------------------*/
|
|
void InitMFOutlineVars() {
|
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/*
|
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** Parameters: none
|
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** Globals: none
|
|
** Operation: This routine initializes the global control knobs for
|
|
** all routines in this file.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: Fri Dec 14 10:50:12 1990, DSJ, Created.
|
|
*/
|
|
MakeNormMethod();
|
|
MakeCharNormRange();
|
|
MakeMinNormScaleX();
|
|
MakeMaxNormScaleX();
|
|
MakeMinNormScaleY();
|
|
MakeMaxNormScaleY();
|
|
} /* InitMFOutlineVars */
|
|
|
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|
|
/*---------------------------------------------------------------------------*/
|
|
void MarkDirectionChanges(MFOUTLINE Outline) {
|
|
/*
|
|
** Parameters:
|
|
** Outline micro-feature outline to analyze
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine searches thru the specified outline and finds
|
|
** the points at which the outline changes direction. These
|
|
** points are then marked as "extremities". This routine is
|
|
** used as an alternative to FindExtremities(). It forces the
|
|
** endpoints of the microfeatures to be at the direction
|
|
** changes rather than at the midpoint between direction
|
|
** changes.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: 6/29/90, DSJ, Created.
|
|
*/
|
|
MFOUTLINE Current;
|
|
MFOUTLINE Last;
|
|
MFOUTLINE First;
|
|
|
|
if (DegenerateOutline (Outline))
|
|
return;
|
|
|
|
First = NextDirectionChange (Outline);
|
|
Last = First;
|
|
do {
|
|
Current = NextDirectionChange (Last);
|
|
MarkPoint (PointAt (Current));
|
|
Last = Current;
|
|
}
|
|
while (Last != First);
|
|
|
|
} /* MarkDirectionChanges */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
MFEDGEPT *NewEdgePoint() {
|
|
/*
|
|
** Parameters: none
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine allocates and returns a new edge point for
|
|
** a micro-feature outline.
|
|
** Return: New edge point.
|
|
** Exceptions: none
|
|
** History: 7/21/89, DSJ, Created.
|
|
*/
|
|
return ((MFEDGEPT *) c_alloc_struct (sizeof (MFEDGEPT), "MFEDGEPT"));
|
|
|
|
} /* NewEdgePoint */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
MFOUTLINE NextExtremity(MFOUTLINE EdgePoint) {
|
|
/*
|
|
** Parameters:
|
|
** EdgePoint start search from this point
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine returns the next point in the micro-feature
|
|
** outline that is an extremity. The search starts after
|
|
** EdgePoint. The routine assumes that the outline being
|
|
** searched is not a degenerate outline (i.e. it must have
|
|
** 2 or more edge points).
|
|
** Return: Next extremity in the outline after EdgePoint.
|
|
** Exceptions: none
|
|
** History: 7/26/89, DSJ, Created.
|
|
*/
|
|
EdgePoint = NextPointAfter (EdgePoint);
|
|
while (NotExtremity (PointAt (EdgePoint)))
|
|
EdgePoint = NextPointAfter (EdgePoint);
|
|
|
|
return (EdgePoint);
|
|
|
|
} /* NextExtremity */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void NormalizeOutline(MFOUTLINE Outline,
|
|
LINE_STATS *LineStats,
|
|
FLOAT32 XOrigin) {
|
|
/*
|
|
** Parameters:
|
|
** Outline outline to be normalized
|
|
** LineStats statistics for text line normalization
|
|
** XOrigin x-origin of text
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine normalizes the coordinates of the specified
|
|
** outline so that the outline is deskewed down to the
|
|
** baseline, translated so that x=0 is at XOrigin, and scaled
|
|
** so that the height of a character cell from descender to
|
|
** ascender is 1. Of this height, 0.25 is for the descender,
|
|
** 0.25 for the ascender, and 0.5 for the x-height. The
|
|
** y coordinate of the baseline is 0.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: 8/2/89, DSJ, Created.
|
|
** 10/23/89, DSJ, Added ascender/descender stretching.
|
|
** 11/89, DSJ, Removed ascender/descender stretching.
|
|
*/
|
|
MFEDGEPT *Current;
|
|
MFOUTLINE EdgePoint;
|
|
FLOAT32 ScaleFactor;
|
|
FLOAT32 AscStretch;
|
|
FLOAT32 DescStretch;
|
|
|
|
if (Outline != NIL) {
|
|
ScaleFactor = ComputeScaleFactor (LineStats);
|
|
AscStretch = 1.0;
|
|
DescStretch = 1.0;
|
|
|
|
EdgePoint = Outline;
|
|
do {
|
|
Current = PointAt (EdgePoint);
|
|
|
|
YPositionOf (Current) = ScaleFactor *
|
|
(YPositionOf (Current) -
|
|
BaselineAt (LineStats, XPositionOf (Current)));
|
|
|
|
if (YPositionOf (Current) > NORMAL_X_HEIGHT)
|
|
YPositionOf (Current) = NORMAL_X_HEIGHT +
|
|
(YPositionOf (Current) - NORMAL_X_HEIGHT) / AscStretch;
|
|
|
|
else if (YPositionOf (Current) < NORMAL_BASELINE)
|
|
YPositionOf (Current) = NORMAL_BASELINE +
|
|
(YPositionOf (Current) - NORMAL_BASELINE) / DescStretch;
|
|
|
|
XPositionOf (Current) = ScaleFactor *
|
|
(XPositionOf (Current) - XOrigin);
|
|
|
|
EdgePoint = NextPointAfter (EdgePoint);
|
|
}
|
|
while (EdgePoint != Outline);
|
|
}
|
|
} /* NormalizeOutline */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void NormalizeOutlines(LIST Outlines,
|
|
LINE_STATS *LineStats,
|
|
FLOAT32 *XScale,
|
|
FLOAT32 *YScale) {
|
|
/*
|
|
** Parameters:
|
|
** Outlines list of outlines to be normalized
|
|
** LineStats statistics for text line normalization
|
|
** XScale x-direction scale factor used by routine
|
|
** YScale y-direction scale factor used by routine
|
|
** Globals:
|
|
** NormMethod method being used for normalization
|
|
** CharNormRange map radius of gyration to this value
|
|
** Operation: This routine normalizes every outline in Outlines
|
|
** according to the currently selected normalization method.
|
|
** It also returns the scale factors that it used to do this
|
|
** scaling. The scale factors returned represent the x and
|
|
** y sizes in the normalized coordinate system that correspond
|
|
** to 1 pixel in the original coordinate system.
|
|
** Return: none (Outlines are changed and XScale and YScale are updated)
|
|
** Exceptions: none
|
|
** History: Fri Dec 14 08:14:55 1990, DSJ, Created.
|
|
*/
|
|
MFOUTLINE Outline;
|
|
OUTLINE_STATS OutlineStats;
|
|
FLOAT32 BaselineScale;
|
|
|
|
switch (NormMethod) {
|
|
case character:
|
|
ComputeOutlineStats(Outlines, &OutlineStats);
|
|
|
|
/* limit scale factor to avoid overscaling small blobs (.,`'),
|
|
thin blobs (l1ift), and merged blobs */
|
|
*XScale = *YScale = BaselineScale = ComputeScaleFactor (LineStats);
|
|
*XScale *= OutlineStats.Ry;
|
|
*YScale *= OutlineStats.Rx;
|
|
if (*XScale < MinNormScaleX)
|
|
*XScale = MinNormScaleX;
|
|
if (*YScale < MinNormScaleY)
|
|
*YScale = MinNormScaleY;
|
|
if (*XScale > MaxNormScaleX && *YScale <= MaxNormScaleY)
|
|
*XScale = MaxNormScaleX;
|
|
*XScale = CharNormRange * BaselineScale / *XScale;
|
|
*YScale = CharNormRange * BaselineScale / *YScale;
|
|
|
|
iterate(Outlines) {
|
|
Outline = (MFOUTLINE) first_node (Outlines);
|
|
CharNormalizeOutline (Outline,
|
|
OutlineStats.x, OutlineStats.y,
|
|
*XScale, *YScale);
|
|
}
|
|
break;
|
|
|
|
case baseline:
|
|
iterate(Outlines) {
|
|
Outline = (MFOUTLINE) first_node (Outlines);
|
|
NormalizeOutline (Outline, LineStats, 0.0);
|
|
}
|
|
*XScale = *YScale = ComputeScaleFactor (LineStats);
|
|
break;
|
|
}
|
|
} /* NormalizeOutlines */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void SettupBlobConversion(TBLOB *Blob) {
|
|
/*
|
|
** Parameters:
|
|
** Blob blob that is to be converted
|
|
** Globals:
|
|
** BlobCenter center of blob to be converted
|
|
** Operation: Compute the center of the blob's bounding box and save
|
|
** it in a global variable. This routine must be called before
|
|
** any calls to ConvertOutline. It must be called once per
|
|
** blob.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: Thu May 17 11:06:17 1990, DSJ, Created.
|
|
*/
|
|
ComputeBlobCenter(Blob, &BlobCenter);
|
|
|
|
} /* SettupBlobConversion */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void SmearExtremities(MFOUTLINE Outline, FLOAT32 XScale, FLOAT32 YScale) {
|
|
/*
|
|
** Parameters:
|
|
** Outline outline whose extremities are to be smeared
|
|
** XScale factor used to normalize outline in x dir
|
|
** YScale factor used to normalize outline in y dir
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine smears the extremities of the specified outline.
|
|
** It does this by adding a random number between
|
|
** -0.5 and 0.5 pixels (that is why X/YScale are needed) to
|
|
** the x and y position of the point. This is done so that
|
|
** the discrete nature of the original scanned image does not
|
|
** affect the statistical clustering used during training.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: 1/11/90, DSJ, Created.
|
|
*/
|
|
MFEDGEPT *Current;
|
|
MFOUTLINE EdgePoint;
|
|
FLOAT32 MinXSmear;
|
|
FLOAT32 MaxXSmear;
|
|
FLOAT32 MinYSmear;
|
|
FLOAT32 MaxYSmear;
|
|
|
|
if (Outline != NIL) {
|
|
MinXSmear = -0.5 * XScale;
|
|
MaxXSmear = 0.5 * XScale;
|
|
MinYSmear = -0.5 * YScale;
|
|
MaxYSmear = 0.5 * YScale;
|
|
EdgePoint = Outline;
|
|
do {
|
|
Current = PointAt (EdgePoint);
|
|
if (IsExtremity (Current)) {
|
|
XPositionOf (Current) +=
|
|
UniformRandomNumber(MinXSmear, MaxXSmear);
|
|
YPositionOf (Current) +=
|
|
UniformRandomNumber(MinYSmear, MaxYSmear);
|
|
}
|
|
|
|
EdgePoint = NextPointAfter (EdgePoint);
|
|
}
|
|
while (EdgePoint != Outline);
|
|
}
|
|
} /* SmearExtremities */
|
|
|
|
|
|
/**----------------------------------------------------------------------------
|
|
Private Code
|
|
----------------------------------------------------------------------------**/
|
|
/*---------------------------------------------------------------------------*/
|
|
void ChangeDirection(MFOUTLINE Start, MFOUTLINE End, DIRECTION Direction) {
|
|
/*
|
|
** Parameters:
|
|
** Start, End defines segment of outline to be modified
|
|
** Direction new direction to assign to segment
|
|
** Globals: none
|
|
** Operation: Change the direction of every vector in the specified
|
|
** outline segment to Direction. The segment to be changed
|
|
** starts at Start and ends at End. Note that the previous
|
|
** direction of End must also be changed to reflect the
|
|
** change in direction of the point before it.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: Fri May 4 10:42:04 1990, DSJ, Created.
|
|
*/
|
|
MFOUTLINE Current;
|
|
|
|
for (Current = Start; Current != End; Current = NextPointAfter (Current))
|
|
DirectionOf (PointAt (Current)) = Direction;
|
|
|
|
PreviousDirectionOf (PointAt (End)) = Direction;
|
|
|
|
} /* ChangeDirection */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void CharNormalizeOutline(MFOUTLINE Outline,
|
|
FLOAT32 XCenter,
|
|
FLOAT32 YCenter,
|
|
FLOAT32 XScale,
|
|
FLOAT32 YScale) {
|
|
/*
|
|
** Parameters:
|
|
** Outline outline to be character normalized
|
|
** XCenter, YCenter center point for normalization
|
|
** XScale, YScale scale factors for normalization
|
|
** Globals: none
|
|
** Operation: This routine normalizes each point in Outline by
|
|
** translating it to the specified center and scaling it
|
|
** anisotropically according to the given scale factors.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: Fri Dec 14 10:27:11 1990, DSJ, Created.
|
|
*/
|
|
MFOUTLINE First, Current;
|
|
MFEDGEPT *CurrentPoint;
|
|
|
|
if (Outline == NIL)
|
|
return;
|
|
|
|
First = Outline;
|
|
Current = First;
|
|
do {
|
|
CurrentPoint = PointAt (Current);
|
|
XPositionOf (CurrentPoint) =
|
|
(XPositionOf (CurrentPoint) - XCenter) * XScale;
|
|
YPositionOf (CurrentPoint) =
|
|
(YPositionOf (CurrentPoint) - YCenter) * YScale;
|
|
|
|
Current = NextPointAfter (Current);
|
|
}
|
|
while (Current != First);
|
|
|
|
} /* CharNormalizeOutline */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void ComputeDirection(MFEDGEPT *Start,
|
|
MFEDGEPT *Finish,
|
|
FLOAT32 MinSlope,
|
|
FLOAT32 MaxSlope) {
|
|
/*
|
|
** Parameters:
|
|
** Start starting point to compute direction from
|
|
** Finish finishing point to compute direction to
|
|
** MinSlope slope below which lines are horizontal
|
|
** MaxSlope slope above which lines are vertical
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine computes the slope from Start to Finish and
|
|
** and then computes the approximate direction of the line
|
|
** segment from Start to Finish. The direction is quantized
|
|
** into 8 buckets:
|
|
** N, S, E, W, NE, NW, SE, SW
|
|
** Both the slope and the direction are then stored into
|
|
** the appropriate fields of the Start edge point. The
|
|
** direction is also stored into the PreviousDirection field
|
|
** of the Finish edge point.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: 7/25/89, DSJ, Created.
|
|
*/
|
|
FVECTOR Delta;
|
|
|
|
Delta.x = Finish->Point.x - Start->Point.x;
|
|
Delta.y = Finish->Point.y - Start->Point.y;
|
|
if (Delta.x == 0)
|
|
if (Delta.y < 0) {
|
|
Start->Slope = -MAX_FLOAT32;
|
|
Start->Direction = south;
|
|
}
|
|
else {
|
|
Start->Slope = MAX_FLOAT32;
|
|
Start->Direction = north;
|
|
}
|
|
else {
|
|
Start->Slope = Delta.y / Delta.x;
|
|
if (Delta.x > 0)
|
|
if (Delta.y > 0)
|
|
if (Start->Slope > MinSlope)
|
|
if (Start->Slope < MaxSlope)
|
|
Start->Direction = northeast;
|
|
else
|
|
Start->Direction = north;
|
|
else
|
|
Start->Direction = east;
|
|
else if (Start->Slope < -MinSlope)
|
|
if (Start->Slope > -MaxSlope)
|
|
Start->Direction = southeast;
|
|
else
|
|
Start->Direction = south;
|
|
else
|
|
Start->Direction = east;
|
|
else if (Delta.y > 0)
|
|
if (Start->Slope < -MinSlope)
|
|
if (Start->Slope > -MaxSlope)
|
|
Start->Direction = northwest;
|
|
else
|
|
Start->Direction = north;
|
|
else
|
|
Start->Direction = west;
|
|
else if (Start->Slope > MinSlope)
|
|
if (Start->Slope < MaxSlope)
|
|
Start->Direction = southwest;
|
|
else
|
|
Start->Direction = south;
|
|
else
|
|
Start->Direction = west;
|
|
}
|
|
Finish->PreviousDirection = Start->Direction;
|
|
} /* ComputeDirection */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void FinishOutlineStats(register OUTLINE_STATS *OutlineStats) {
|
|
/*
|
|
** Parameters:
|
|
** OutlineStats statistics about a set of outlines
|
|
** Globals: none
|
|
** Operation: Use the preliminary statistics accumulated in OutlineStats
|
|
** to compute the final statistics.
|
|
** (see Dan Johnson's Tesseract lab
|
|
** notebook #2, pgs. 74-78).
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: Fri Dec 14 10:13:36 1990, DSJ, Created.
|
|
*/
|
|
OutlineStats->x = 0.5 * OutlineStats->My / OutlineStats->L;
|
|
OutlineStats->y = 0.5 * OutlineStats->Mx / OutlineStats->L;
|
|
|
|
OutlineStats->Ix = (OutlineStats->Ix / 3.0 -
|
|
OutlineStats->y * OutlineStats->Mx +
|
|
OutlineStats->y * OutlineStats->y * OutlineStats->L);
|
|
|
|
OutlineStats->Iy = (OutlineStats->Iy / 3.0 -
|
|
OutlineStats->x * OutlineStats->My +
|
|
OutlineStats->x * OutlineStats->x * OutlineStats->L);
|
|
|
|
/* Ix and/or Iy could possibly be negative due to roundoff error */
|
|
if (OutlineStats->Ix < 0.0)
|
|
OutlineStats->Ix = MIN_INERTIA;
|
|
if (OutlineStats->Iy < 0.0)
|
|
OutlineStats->Iy = MIN_INERTIA;
|
|
|
|
OutlineStats->Rx = sqrt (OutlineStats->Ix / OutlineStats->L);
|
|
OutlineStats->Ry = sqrt (OutlineStats->Iy / OutlineStats->L);
|
|
|
|
OutlineStats->Mx *= 0.5;
|
|
OutlineStats->My *= 0.5;
|
|
|
|
} /* FinishOutlineStats */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void InitOutlineStats(OUTLINE_STATS *OutlineStats) {
|
|
/*
|
|
** Parameters:
|
|
** OutlineStats stats data structure to be initialized
|
|
** Globals: none
|
|
** Operation: Initialize the outline statistics data structure so
|
|
** that it is ready to start accumulating statistics.
|
|
** Return: none
|
|
** Exceptions: none
|
|
** History: Fri Dec 14 08:55:22 1990, DSJ, Created.
|
|
*/
|
|
OutlineStats->Mx = 0.0;
|
|
OutlineStats->My = 0.0;
|
|
OutlineStats->L = 0.0;
|
|
OutlineStats->x = 0.0;
|
|
OutlineStats->y = 0.0;
|
|
OutlineStats->Ix = 0.0;
|
|
OutlineStats->Iy = 0.0;
|
|
OutlineStats->Rx = 0.0;
|
|
OutlineStats->Ry = 0.0;
|
|
} /* InitOutlineStats */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
MFOUTLINE NextDirectionChange(MFOUTLINE EdgePoint) {
|
|
/*
|
|
** Parameters:
|
|
** EdgePoint start search from this point
|
|
** Globals: none
|
|
** Operation:
|
|
** This routine returns the next point in the micro-feature
|
|
** outline that has a direction different than EdgePoint. The
|
|
** routine assumes that the outline being searched is not a
|
|
** degenerate outline (i.e. it must have 2 or more edge points).
|
|
** Return: Point of next direction change in micro-feature outline.
|
|
** Exceptions: none
|
|
** History: 7/25/89, DSJ, Created.
|
|
*/
|
|
DIRECTION InitialDirection;
|
|
|
|
InitialDirection = DirectionOf (PointAt (EdgePoint));
|
|
|
|
do
|
|
EdgePoint = NextPointAfter (EdgePoint);
|
|
while (DirectionOf (PointAt (EdgePoint)) == InitialDirection);
|
|
|
|
return (EdgePoint);
|
|
} /* NextDirectionChange */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void UpdateOutlineStats(register OUTLINE_STATS *OutlineStats,
|
|
register FLOAT32 x1,
|
|
register FLOAT32 x2,
|
|
register FLOAT32 y1,
|
|
register FLOAT32 y2) {
|
|
/*
|
|
** Parameters:
|
|
** OutlineStats statistics to add this segment to
|
|
** x1, y1, x2, y2 segment to be added to statistics
|
|
** Globals: none
|
|
** Operation: This routine adds the statistics for the specified
|
|
** line segment to OutlineStats. The statistics that are
|
|
** kept are:
|
|
** sum of length of all segments
|
|
** sum of 2*Mx for all segments
|
|
** sum of 2*My for all segments
|
|
** sum of 2*Mx*(y1+y2) - L*y1*y2 for all segments
|
|
** sum of 2*My*(x1+x2) - L*x1*x2 for all segments
|
|
** These numbers, once collected can later be used to easily
|
|
** compute the center of mass, first and second moments,
|
|
** and radii of gyration. (see Dan Johnson's Tesseract lab
|
|
** notebook #2, pgs. 74-78).
|
|
** Return: none
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** Exceptions: none
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** History: Fri Dec 14 08:59:17 1990, DSJ, Created.
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*/
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register FLOAT64 L;
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register FLOAT64 Mx2;
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register FLOAT64 My2;
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/* compute length of segment */
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L = sqrt ((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
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OutlineStats->L += L;
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/* compute 2Mx and 2My components */
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Mx2 = L * (y1 + y2);
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My2 = L * (x1 + x2);
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OutlineStats->Mx += Mx2;
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OutlineStats->My += My2;
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/* compute second moment component */
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OutlineStats->Ix += Mx2 * (y1 + y2) - L * y1 * y2;
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OutlineStats->Iy += My2 * (x1 + x2) - L * x1 * x2;
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} /* UpdateOutlineStats */
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