1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
package hocr
import (
"encoding/xml"
"errors"
"io/ioutil"
"regexp"
"strconv"
"strings"
)
type Hocr struct {
Lines []OcrLine `xml:"body>div>div>p>span"`
}
type OcrLine struct {
Class string `xml:"class,attr"`
Id string `xml:"id,attr"`
Title string `xml:"title,attr"`
Words []OcrWord `xml:"span"`
Text string `xml:",chardata"`
}
type OcrWord struct {
Class string `xml:"class,attr"`
Id string `xml:"id,attr"`
Title string `xml:"title,attr"`
Chars []OcrChar `xml:"span"`
Text string `xml:",chardata"`
}
type OcrChar struct {
Class string `xml:"class,attr"`
Id string `xml:"id,attr"`
Title string `xml:"title,attr"`
Chars []OcrChar `xml:"span"`
Text string `xml:",chardata"`
}
// Returns the confidence for a word based on its x_wconf value
func wordConf(s string) (float64, error) {
re, err := regexp.Compile(`x_wconf ([0-9.]+)`)
if err != nil {
return 0.0, err
}
conf := re.FindStringSubmatch(s)
return strconv.ParseFloat(conf[1], 64)
}
func BoxCoords(s string) ([4]int, error) {
var coords [4]int
re, err := regexp.Compile(`bbox ([0-9]+) ([0-9]+) ([0-9]+) ([0-9]+)`)
if err != nil {
return coords, err
}
coordstr := re.FindStringSubmatch(s)
for i := range coords {
c, err := strconv.Atoi(coordstr[i+1])
if err != nil {
return coords, err
}
coords[i] = c
}
return coords, nil
}
func noText(s string) bool {
t := strings.Trim(s, " \n")
return len(t) == 0
}
func Parse(b []byte) (Hocr, error) {
var hocr Hocr
err := xml.Unmarshal(b, &hocr)
if err != nil {
return hocr, err
}
return hocr, nil
}
func GetText(hocrfn string) (string, error) {
var s string
file, err := ioutil.ReadFile(hocrfn)
if err != nil {
return s, err
}
h, err := Parse(file)
if err != nil {
return s, err
}
for _, l := range h.Lines {
s += LineText(l) + "\n"
}
return s, nil
}
func GetAvgConf(hocrfn string) (float64, error) {
file, err := ioutil.ReadFile(hocrfn)
if err != nil {
return 0, err
}
h, err := Parse(file)
if err != nil {
return 0, err
}
var total, num float64
for _, l := range h.Lines {
for _, w := range l.Words {
c, err := wordConf(w.Title)
if err != nil {
return 0, err
}
total += c
num++
}
}
if num == 0 {
return 0, errors.New("No words found")
}
return total / num, nil
}
// GetWordConfs is a utility function that parses a hocr
// file and returns an array containing the confidences
// of each word therein.
func GetWordConfs(hocrfn string) ([]float64, error) {
var confs []float64
file, err := ioutil.ReadFile(hocrfn)
if err != nil {
return confs, err
}
h, err := Parse(file)
if err != nil {
return confs, err
}
for _, l := range h.Lines {
for _, w := range l.Words {
c, err := wordConf(w.Title)
if err != nil {
return confs, err
}
confs = append(confs, c)
}
}
return confs, nil
}
|
