tesseract/unittest/lang_model_test.cc
Stefan Weil f93fb9de74 unittest: Add lang_model_test (only works partially)
The test currently has subtests which fail because of missing files.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
2018-10-12 16:23:13 +02:00

115 lines
4.9 KiB
C++

// (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> // for std::string
#include "absl/strings/str_cat.h"
#include "gmock/gmock.h" // for testing::ElementsAreArray
#include "include_gunit.h"
#include "lang_model_helpers.h"
#include "log.h" // for LOG
#include "lstmtrainer.h"
#include "unicharset_training_utils.h"
namespace tesseract {
namespace {
std::string TestDataNameToPath(const std::string& name) {
return file::JoinPath(TESTING_DIR, name);
}
// This is an integration test that verifies that CombineLangModel works to
// the extent that an LSTMTrainer can be initialized with the result, and it
// can encode strings. More importantly, the test verifies that adding an extra
// character to the unicharset does not change the encoding of strings.
TEST(LangModelTest, AddACharacter) {
constexpr char kTestString[] = "Simple ASCII string to encode !@#$%&";
constexpr char kTestStringRupees[] = "ASCII string with Rupee symbol ₹";
// Setup the arguments.
std::string script_dir = LANGDATA_DIR;
std::string eng_dir = file::JoinPath(script_dir, "eng");
std::string unicharset_path = TestDataNameToPath("eng_beam.unicharset");
UNICHARSET unicharset;
EXPECT_TRUE(unicharset.load_from_file(unicharset_path.c_str()));
std::string version_str = "TestVersion";
std::string output_dir = FLAGS_test_tmpdir;
LOG(INFO) << "Output dir=" << output_dir;
std::string lang1 = "eng";
bool pass_through_recoder = false;
GenericVector<STRING> words, puncs, numbers;
// If these reads fail, we get a warning message and an empty list of words.
ReadFile(file::JoinPath(eng_dir, "eng.wordlist"), nullptr)
.split('\n', &words);
EXPECT_GT(words.size(), 0);
ReadFile(file::JoinPath(eng_dir, "eng.punc"), nullptr).split('\n', &puncs);
EXPECT_GT(puncs.size(), 0);
ReadFile(file::JoinPath(eng_dir, "eng.numbers"), nullptr)
.split('\n', &numbers);
EXPECT_GT(numbers.size(), 0);
bool lang_is_rtl = false;
// Generate the traineddata file.
EXPECT_EQ(0, CombineLangModel(unicharset, script_dir, version_str, output_dir,
lang1, pass_through_recoder, words, puncs,
numbers, lang_is_rtl, nullptr, nullptr));
// Init a trainer with it, and encode a string.
std::string traineddata1 =
file::JoinPath(output_dir, lang1, absl::StrCat(lang1, ".traineddata"));
LSTMTrainer trainer1;
trainer1.InitCharSet(traineddata1);
GenericVector<int> labels1;
EXPECT_TRUE(trainer1.EncodeString(kTestString, &labels1));
// Add a new character to the unicharset and try again.
int size_before = unicharset.size();
unicharset.unichar_insert("");
SetupBasicProperties(/*report_errors*/ true, /*decompose (NFD)*/ false,
&unicharset);
EXPECT_EQ(size_before + 1, unicharset.size());
// Generate the traineddata file.
std::string lang2 = "extended";
EXPECT_EQ(EXIT_SUCCESS,
CombineLangModel(unicharset, script_dir, version_str, output_dir,
lang2, pass_through_recoder, words, puncs, numbers,
lang_is_rtl, nullptr, nullptr));
// Init a trainer with it, and encode a string.
std::string traineddata2 =
file::JoinPath(output_dir, lang2, absl::StrCat(lang2, ".traineddata"));
LSTMTrainer trainer2;
trainer2.InitCharSet(traineddata2);
GenericVector<int> labels2;
EXPECT_TRUE(trainer2.EncodeString(kTestString, &labels2));
// Copy labels1 to a std::vector, renumbering the null char to match trainer2.
// Since Tensor Flow's CTC implementation insists on having the null be the
// last label, and we want to be compatible, null has to be renumbered when
// we add a class.
int null1 = trainer1.null_char();
int null2 = trainer2.null_char();
EXPECT_EQ(null1 + 1, null2);
std::vector<int> labels1_v(labels1.size());
for (int i = 0; i < labels1.size(); ++i) {
if (labels1[i] == null1)
labels1_v[i] = null2;
else
labels1_v[i] = labels1[i];
}
EXPECT_THAT(labels1_v,
testing::ElementsAreArray(&labels2[0], labels2.size()));
// To make sure we we are not cheating somehow, we can now encode the Rupee
// symbol, which we could not do before.
EXPECT_FALSE(trainer1.EncodeString(kTestStringRupees, &labels1));
EXPECT_TRUE(trainer2.EncodeString(kTestStringRupees, &labels2));
}
} // namespace
} // namespace tesseract