tesseract  5.0.0
layout_test.cc
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1 // (C) Copyright 2017, Google Inc.
2 // Licensed under the Apache License, Version 2.0 (the "License");
3 // you may not use this file except in compliance with the License.
4 // You may obtain a copy of the License at
5 // http://www.apache.org/licenses/LICENSE-2.0
6 // Unless required by applicable law or agreed to in writing, software
7 // distributed under the License is distributed on an "AS IS" BASIS,
8 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
9 // See the License for the specific language governing permissions and
10 // limitations under the License.
11 
12 #include <string>
13 #include <utility>
14 
15 #include "include_gunit.h"
16 
17 #include <allheaders.h>
18 #include <tesseract/baseapi.h>
20 #include "coutln.h"
21 #include "log.h" // for LOG
22 #include "mutableiterator.h"
23 #include "ocrblock.h" // for class BLOCK
24 #include "pageres.h"
25 #include "polyblk.h"
26 #include "stepblob.h"
27 
28 namespace tesseract {
29 
31 static const char *kPolyBlockNames[] = {
32  "Unknown",
33  "Flowing Text",
34  "Heading Text",
35  "Pullout Text",
36  "Equation",
37  "Inline Equation",
38  "Table",
39  "Vertical Text",
40  "Caption Text",
41  "Flowing Image",
42  "Heading Image",
43  "Pullout Image",
44  "Horizontal Line",
45  "Vertical Line",
46  "Noise",
47  "" // End marker for testing that sizes match.
48 };
49 
50 const char *kStrings8087_054[] = {"dat", "Dalmatian", "", "DAMAGED DURING", "margarine,", nullptr};
53 
54 // The fixture for testing Tesseract.
55 class LayoutTest : public testing::Test {
56 protected:
57  std::string TestDataNameToPath(const std::string &name) {
58  return file::JoinPath(TESTING_DIR, "/" + name);
59  }
60  std::string TessdataPath() {
61  return file::JoinPath(TESSDATA_DIR, "");
62  }
63 
65  src_pix_ = nullptr;
66  }
67  ~LayoutTest() override {
68  src_pix_.destroy();
69  }
70 
71  void SetImage(const char *filename, const char *lang) {
72  src_pix_.destroy();
73  src_pix_ = pixRead(TestDataNameToPath(filename).c_str());
77  }
78 
79  // Tests reading order and block finding (very roughly) by iterating
80  // over the blocks, expecting that they contain the strings in order,
81  // allowing for other blocks in between.
82  // An empty string should match an image block, and a nullptr string
83  // indicates the end of the array.
84  void VerifyBlockTextOrder(const char *strings[], const PolyBlockType *blocks,
85  ResultIterator *it) {
86  it->Begin();
87  int string_index = 0;
88  int block_index = 0;
89  do {
90  char *block_text = it->GetUTF8Text(tesseract::RIL_BLOCK);
91  if (block_text != nullptr && it->BlockType() == blocks[string_index] &&
92  strstr(block_text, strings[string_index]) != nullptr) {
93  LOG(INFO) << "Found string " << strings[string_index] << " in block " << block_index
94  << " of type " << kPolyBlockNames[blocks[string_index]] << "\n";
95  // Found this one.
96  ++string_index;
97  } else if (it->BlockType() == blocks[string_index] && block_text == nullptr &&
98  strings[string_index][0] == '\0') {
99  LOG(INFO) << "Found block of type " << kPolyBlockNames[blocks[string_index]] << " at block "
100  << block_index << "\n";
101  // Found this one.
102  ++string_index;
103  } else {
104  LOG(INFO) << "No match found in block with text:\n" << block_text;
105  }
106  delete[] block_text;
107  ++block_index;
108  if (strings[string_index] == nullptr) {
109  break;
110  }
111  } while (it->Next(tesseract::RIL_BLOCK));
112  EXPECT_TRUE(strings[string_index] == nullptr);
113  }
114 
115  // Tests that approximate order of the biggest text blocks is correct.
116  // Correctness is tested by the following simple rules:
117  // If a block overlaps its predecessor in x, then it must be below it.
118  // otherwise, if the block is not below its predecessor, then it must
119  // be to the left of it if right_to_left is true, or to the right otherwise.
120  void VerifyRoughBlockOrder(bool right_to_left, ResultIterator *it) {
121  int prev_left = 0;
122  int prev_right = 0;
123  int prev_bottom = 0;
124  it->Begin();
125  do {
126  int left, top, right, bottom;
127  if (it->BoundingBox(tesseract::RIL_BLOCK, &left, &top, &right, &bottom) &&
128  PTIsTextType(it->BlockType()) && right - left > 800 && bottom - top > 200) {
129  if (prev_right > prev_left) {
130  if (std::min(right, prev_right) > std::max(left, prev_left)) {
131  EXPECT_GE(top, prev_bottom) << "Overlapping block should be below";
132  } else if (top < prev_bottom) {
133  if (right_to_left) {
134  EXPECT_GE(prev_left, right) << "Block should be to the left";
135  } else {
136  EXPECT_GE(left, prev_right) << "Block should be to the right";
137  }
138  }
139  }
140  prev_left = left;
141  prev_right = right;
142  prev_bottom = bottom;
143  }
144  } while (it->Next(tesseract::RIL_BLOCK));
145  }
146 
147  // Tests that every blob assigned to the biggest text blocks is contained
148  // fully within its block by testing that the block polygon winds around
149  // the center of the bounding boxes of the outlines in the blob.
150  void VerifyTotalContainment(int winding_target, MutableIterator *it) {
151  it->Begin();
152  do {
153  int left, top, right, bottom;
154  if (it->BoundingBox(tesseract::RIL_BLOCK, &left, &top, &right, &bottom) &&
155  PTIsTextType(it->BlockType()) && right - left > 800 && bottom - top > 200) {
156  const PAGE_RES_IT *pr_it = it->PageResIt();
157  POLY_BLOCK *pb = pr_it->block()->block->pdblk.poly_block();
158  CHECK(pb != nullptr);
159  FCOORD skew = pr_it->block()->block->skew();
160  EXPECT_GT(skew.x(), 0.0f);
161  EXPECT_GT(skew.y(), 0.0f);
162  // Iterate the words in the block.
163  MutableIterator word_it = *it;
164  do {
165  const PAGE_RES_IT *w_it = word_it.PageResIt();
166  // Iterate the blobs in the word.
167  C_BLOB_IT b_it(w_it->word()->word->cblob_list());
168  for (b_it.mark_cycle_pt(); !b_it.cycled_list(); b_it.forward()) {
169  C_BLOB *blob = b_it.data();
170  // Iterate the outlines in the blob.
171  C_OUTLINE_IT ol_it(blob->out_list());
172  for (ol_it.mark_cycle_pt(); !ol_it.cycled_list(); ol_it.forward()) {
173  C_OUTLINE *ol = ol_it.data();
174  TBOX box = ol->bounding_box();
175  ICOORD middle((box.left() + box.right()) / 2, (box.top() + box.bottom()) / 2);
176  EXPECT_EQ(winding_target, pb->winding_number(middle));
177  }
178  }
179  } while (word_it.Next(tesseract::RIL_WORD) &&
181  }
182  } while (it->Next(tesseract::RIL_BLOCK));
183  }
184 
186  std::string ocr_text_;
188 };
189 
190 // Tests that array sizes match their intended size.
191 TEST_F(LayoutTest, ArraySizeTest) {
192  int size = 0;
193  for (size = 0; kPolyBlockNames[size][0] != '\0'; ++size) {
194  ;
195  }
196  EXPECT_EQ(size, PT_COUNT);
197 }
198 
199 // Tests that Tesseract gets the important blocks and in the right order
200 // on a UNLV page numbered 8087_054.3B.tif. (Dubrovnik)
201 TEST_F(LayoutTest, UNLV8087_054) {
202  SetImage("8087_054.3B.tif", "eng");
203  // Just run recognition.
204  EXPECT_EQ(api_.Recognize(nullptr), 0);
205  // Check iterator position.
206  tesseract::ResultIterator *it = api_.GetIterator();
207  VerifyBlockTextOrder(kStrings8087_054, kBlocks8087_054, it);
208  delete it;
209 }
210 
211 // Tests that Tesseract gets the important blocks and in the right order
212 // on GOOGLE:13510798882202548:74:84.sj-79.tif (Hebrew image)
213 // TODO: replace hebrew.png by Google image referred above
214 TEST_F(LayoutTest, HebrewOrderingAndSkew) {
215  SetImage("hebrew.png", "eng");
216  // Just run recognition.
217  EXPECT_EQ(api_.Recognize(nullptr), 0);
218  tesseract::MutableIterator *it = api_.GetMutableIterator();
219  // In eng mode, block order should not be RTL.
220  VerifyRoughBlockOrder(false, it);
221  VerifyTotalContainment(1, it);
222  delete it;
223  // Now try again using Hebrew.
224  SetImage("hebrew.png", "heb");
225  // Just run recognition.
226  EXPECT_EQ(api_.Recognize(nullptr), 0);
227  it = api_.GetMutableIterator();
228  // In heb mode, block order should be RTL.
229  VerifyRoughBlockOrder(true, it);
230  // And blobs should still be fully contained.
231  VerifyTotalContainment(-1, it);
232  delete it;
233 }
234 
235 } // namespace tesseract
@ LOG
#define CHECK(condition)
Definition: include_gunit.h:76
@ INFO
Definition: log.h:28
@ OEM_TESSERACT_ONLY
Definition: publictypes.h:266
@ PSM_AUTO
Fully automatic page segmentation, but no OSD.
Definition: publictypes.h:164
const char * kStrings8087_054[]
Definition: layout_test.cc:50
const PolyBlockType kBlocks8087_054[]
Definition: layout_test.cc:51
bool PTIsTextType(PolyBlockType type)
Definition: publictypes.h:82
TEST_F(EuroText, FastLatinOCR)
@ PT_PULLOUT_IMAGE
Definition: publictypes.h:65
@ PT_CAPTION_TEXT
Definition: publictypes.h:62
@ PT_HEADING_TEXT
Definition: publictypes.h:56
@ PT_FLOWING_TEXT
Definition: publictypes.h:55
void SetPageSegMode(PageSegMode mode)
Definition: baseapi.cpp:508
int Init(const char *datapath, const char *language, OcrEngineMode mode, char **configs, int configs_size, const std::vector< std::string > *vars_vec, const std::vector< std::string > *vars_values, bool set_only_non_debug_params)
Definition: baseapi.cpp:365
void SetImage(const unsigned char *imagedata, int width, int height, int bytes_per_pixel, int bytes_per_line)
Definition: baseapi.cpp:573
PolyBlockType BlockType() const
bool BoundingBox(PageIteratorLevel level, int *left, int *top, int *right, int *bottom) const
virtual char * GetUTF8Text(PageIteratorLevel level) const
bool IsAtBeginningOf(PageIteratorLevel level) const override
bool Next(PageIteratorLevel level) override
const PAGE_RES_IT * PageResIt() const
const TBOX & bounding_box() const
Definition: coutln.h:113
void destroy()
Definition: image.cpp:32
PDBLK pdblk
Page Description Block.
Definition: ocrblock.h:185
FCOORD skew() const
Definition: ocrblock.h:141
WERD_RES * word() const
Definition: pageres.h:763
BLOCK_RES * block() const
Definition: pageres.h:769
POLY_BLOCK * poly_block() const
Definition: pdblock.h:59
integer coordinate
Definition: points.h:36
float y() const
Definition: points.h:209
float x() const
Definition: points.h:206
int16_t winding_number(const ICOORD &test_pt)
Definition: polyblk.cpp:106
TDimension left() const
Definition: rect.h:82
TDimension top() const
Definition: rect.h:68
TDimension right() const
Definition: rect.h:89
TDimension bottom() const
Definition: rect.h:75
C_OUTLINE_LIST * out_list()
Definition: stepblob.h:70
C_BLOB_LIST * cblob_list()
Definition: werd.h:96
static std::string JoinPath(const std::string &s1, const std::string &s2)
Definition: include_gunit.h:65
tesseract::TessBaseAPI api_
Definition: layout_test.cc:187
void SetImage(const char *filename, const char *lang)
Definition: layout_test.cc:71
void VerifyRoughBlockOrder(bool right_to_left, ResultIterator *it)
Definition: layout_test.cc:120
void VerifyBlockTextOrder(const char *strings[], const PolyBlockType *blocks, ResultIterator *it)
Definition: layout_test.cc:84
~LayoutTest() override
Definition: layout_test.cc:67
std::string TestDataNameToPath(const std::string &name)
Definition: layout_test.cc:57
std::string TessdataPath()
Definition: layout_test.cc:60
void VerifyTotalContainment(int winding_target, MutableIterator *it)
Definition: layout_test.cc:150