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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
// (C) Copyright 2017, 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.
#include <string>
#include <utility>
#include "include_gunit.h"
#include <allheaders.h>
#include <tesseract/baseapi.h>
#include <tesseract/resultiterator.h>
#include "coutln.h"
#include "log.h" // for LOG
#include "mutableiterator.h"
#include "ocrblock.h" // for class BLOCK
#include "pageres.h"
#include "polyblk.h"
#include "stepblob.h"
namespace tesseract {
/** String name for each block type. Keep in sync with PolyBlockType. */
static const char *kPolyBlockNames[] = {
"Unknown",
"Flowing Text",
"Heading Text",
"Pullout Text",
"Equation",
"Inline Equation",
"Table",
"Vertical Text",
"Caption Text",
"Flowing Image",
"Heading Image",
"Pullout Image",
"Horizontal Line",
"Vertical Line",
"Noise",
"" // End marker for testing that sizes match.
};
const char *kStrings8087_054[] = {"dat", "Dalmatian", "", "DAMAGED DURING", "margarine,", nullptr};
const PolyBlockType kBlocks8087_054[] = {PT_HEADING_TEXT, PT_FLOWING_TEXT, PT_PULLOUT_IMAGE,
PT_CAPTION_TEXT, PT_FLOWING_TEXT};
// The fixture for testing Tesseract.
class LayoutTest : public testing::Test {
protected:
std::string TestDataNameToPath(const std::string &name) {
return file::JoinPath(TESTING_DIR, "/" + name);
}
std::string TessdataPath() {
return file::JoinPath(TESSDATA_DIR, "");
}
LayoutTest() {
src_pix_ = nullptr;
}
~LayoutTest() override {
src_pix_.destroy();
}
void SetImage(const char *filename, const char *lang) {
src_pix_.destroy();
src_pix_ = pixRead(TestDataNameToPath(filename).c_str());
api_.Init(TessdataPath().c_str(), lang, tesseract::OEM_TESSERACT_ONLY);
api_.SetPageSegMode(tesseract::PSM_AUTO);
api_.SetImage(src_pix_);
}
// Tests reading order and block finding (very roughly) by iterating
// over the blocks, expecting that they contain the strings in order,
// allowing for other blocks in between.
// An empty string should match an image block, and a nullptr string
// indicates the end of the array.
void VerifyBlockTextOrder(const char *strings[], const PolyBlockType *blocks,
ResultIterator *it) {
it->Begin();
int string_index = 0;
int block_index = 0;
do {
char *block_text = it->GetUTF8Text(tesseract::RIL_BLOCK);
if (block_text != nullptr && it->BlockType() == blocks[string_index] &&
strstr(block_text, strings[string_index]) != nullptr) {
LOG(INFO) << "Found string " << strings[string_index] << " in block " << block_index
<< " of type " << kPolyBlockNames[blocks[string_index]] << "\n";
// Found this one.
++string_index;
} else if (it->BlockType() == blocks[string_index] && block_text == nullptr &&
strings[string_index][0] == '\0') {
LOG(INFO) << "Found block of type " << kPolyBlockNames[blocks[string_index]] << " at block "
<< block_index << "\n";
// Found this one.
++string_index;
} else {
LOG(INFO) << "No match found in block with text:\n" << block_text;
}
delete[] block_text;
++block_index;
if (strings[string_index] == nullptr) {
break;
}
} while (it->Next(tesseract::RIL_BLOCK));
EXPECT_TRUE(strings[string_index] == nullptr);
}
// Tests that approximate order of the biggest text blocks is correct.
// Correctness is tested by the following simple rules:
// If a block overlaps its predecessor in x, then it must be below it.
// otherwise, if the block is not below its predecessor, then it must
// be to the left of it if right_to_left is true, or to the right otherwise.
void VerifyRoughBlockOrder(bool right_to_left, ResultIterator *it) {
int prev_left = 0;
int prev_right = 0;
int prev_bottom = 0;
it->Begin();
do {
int left, top, right, bottom;
if (it->BoundingBox(tesseract::RIL_BLOCK, &left, &top, &right, &bottom) &&
PTIsTextType(it->BlockType()) && right - left > 800 && bottom - top > 200) {
if (prev_right > prev_left) {
if (std::min(right, prev_right) > std::max(left, prev_left)) {
EXPECT_GE(top, prev_bottom) << "Overlapping block should be below";
} else if (top < prev_bottom) {
if (right_to_left) {
EXPECT_GE(prev_left, right) << "Block should be to the left";
} else {
EXPECT_GE(left, prev_right) << "Block should be to the right";
}
}
}
prev_left = left;
prev_right = right;
prev_bottom = bottom;
}
} while (it->Next(tesseract::RIL_BLOCK));
}
// Tests that every blob assigned to the biggest text blocks is contained
// fully within its block by testing that the block polygon winds around
// the center of the bounding boxes of the outlines in the blob.
void VerifyTotalContainment(int winding_target, MutableIterator *it) {
it->Begin();
do {
int left, top, right, bottom;
if (it->BoundingBox(tesseract::RIL_BLOCK, &left, &top, &right, &bottom) &&
PTIsTextType(it->BlockType()) && right - left > 800 && bottom - top > 200) {
const PAGE_RES_IT *pr_it = it->PageResIt();
POLY_BLOCK *pb = pr_it->block()->block->pdblk.poly_block();
CHECK(pb != nullptr);
FCOORD skew = pr_it->block()->block->skew();
EXPECT_GT(skew.x(), 0.0f);
EXPECT_GT(skew.y(), 0.0f);
// Iterate the words in the block.
MutableIterator word_it = *it;
do {
const PAGE_RES_IT *w_it = word_it.PageResIt();
// Iterate the blobs in the word.
C_BLOB_IT b_it(w_it->word()->word->cblob_list());
for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
C_BLOB *blob = b_it.data();
// Iterate the outlines in the blob.
C_OUTLINE_IT ol_it(blob->out_list());
for (ol_it.mark_cycle_pt(); !ol_it.cycled_list(); ol_it.forward()) {
C_OUTLINE *ol = ol_it.data();
TBOX box = ol->bounding_box();
ICOORD middle((box.left() + box.right()) / 2, (box.top() + box.bottom()) / 2);
EXPECT_EQ(winding_target, pb->winding_number(middle));
}
}
} while (word_it.Next(tesseract::RIL_WORD) &&
!word_it.IsAtBeginningOf(tesseract::RIL_BLOCK));
}
} while (it->Next(tesseract::RIL_BLOCK));
}
Image src_pix_;
std::string ocr_text_;
tesseract::TessBaseAPI api_;
};
// Tests that array sizes match their intended size.
TEST_F(LayoutTest, ArraySizeTest) {
int size = 0;
for (size = 0; kPolyBlockNames[size][0] != '\0'; ++size) {
;
}
EXPECT_EQ(size, PT_COUNT);
}
// Tests that Tesseract gets the important blocks and in the right order
// on a UNLV page numbered 8087_054.3B.tif. (Dubrovnik)
TEST_F(LayoutTest, UNLV8087_054) {
SetImage("8087_054.3B.tif", "eng");
// Just run recognition.
EXPECT_EQ(api_.Recognize(nullptr), 0);
// Check iterator position.
tesseract::ResultIterator *it = api_.GetIterator();
VerifyBlockTextOrder(kStrings8087_054, kBlocks8087_054, it);
delete it;
}
// Tests that Tesseract gets the important blocks and in the right order
// on GOOGLE:13510798882202548:74:84.sj-79.tif (Hebrew image)
// TODO: replace hebrew.png by Google image referred above
TEST_F(LayoutTest, HebrewOrderingAndSkew) {
SetImage("hebrew.png", "eng");
// Just run recognition.
EXPECT_EQ(api_.Recognize(nullptr), 0);
tesseract::MutableIterator *it = api_.GetMutableIterator();
// In eng mode, block order should not be RTL.
VerifyRoughBlockOrder(false, it);
VerifyTotalContainment(1, it);
delete it;
// Now try again using Hebrew.
SetImage("hebrew.png", "heb");
// Just run recognition.
EXPECT_EQ(api_.Recognize(nullptr), 0);
it = api_.GetMutableIterator();
// In heb mode, block order should be RTL.
VerifyRoughBlockOrder(true, it);
// And blobs should still be fully contained.
VerifyTotalContainment(-1, it);
delete it;
}
} // namespace tesseract
|
