simplify image sample usage (#139)

visualdl/logic/pybind.cc

@@ -118,7 +118,8 @@ PYBIND11_PLUGIN(core) {
       .def("start_sampling", &cp::Image::StartSampling)
       .def("is_sample_taken", &cp::Image::IsSampleTaken)
       .def("finish_sampling", &cp::Image::FinishSampling)
-      .def("set_sample", &cp::Image::SetSample);
+      .def("set_sample", &cp::Image::SetSample)
+      .def("add_sample", &cp::Image::AddSample);
 
   py::class_<cp::ImageReader::ImageRecord>(m, "ImageRecord")
       // TODO(ChunweiYan) make these copyless.

visualdl/logic/sdk.cc

@@ -171,6 +171,14 @@ struct is_same_type<T, T> {
   static const bool value = true;
 };
 
+void Image::AddSample(const std::vector<shape_t>& shape,
+                      const std::vector<value_t>& data) {
+  auto idx = IsSampleTaken();
+  if (idx >= 0) {
+    SetSample(idx, shape, data);
+  }
+}
+
 void Image::SetSample(int index,
                       const std::vector<shape_t>& shape,
                       const std::vector<value_t>& data) {

visualdl/logic/sdk.h

@@ -146,18 +146,29 @@ struct Image {
   }
 
   /*
-   * Start a sampling period.
+   * Start a sampling period, this interface will start a new reservior sampling
+   * phase.
    */
   void StartSampling();
   /*
-   * Will this sample be taken.
+   * End a sampling period, it will clear all states for reservior sampling.
    */
-  int IsSampleTaken();
+  void FinishSampling();
+
   /*
-   * End a sampling period.
+   * A combined interface for IsSampleTaken and SetSample, simpler but might be
+   * low effience.
    */
-  void FinishSampling();
+  void AddSample(const std::vector<shape_t>& shape,
+                 const std::vector<value_t>& data);
 
+  /*
+   * Will this sample be taken, this interface is introduced to reduce the cost
+   * of copy image data, by testing whether this image will be sampled, and only
+   * copy data when it should be sampled. In that way, most of unsampled image
+   * data need not be copied or processed at all.
+   */
+  int IsSampleTaken();
   /*
    * Just store a tensor with nothing to do with image format.
    */

visualdl/logic/sdk_test.cc

@@ -81,6 +81,40 @@ TEST(Image, test) {
   CHECK_EQ(image2read.num_records(), num_steps);
 }
 
+TEST(Image, add_sample_test) {
+  const auto dir = "./tmp/sdk_test.image";
+  LogWriter writer__(dir, 4);
+  auto writer = writer__.AsMode("train");
+
+  auto tablet = writer.AddTablet("image0");
+  components::Image image(tablet, 3, 1);
+  const int num_steps = 10;
+
+  LOG(INFO) << "write images";
+  image.SetCaption("this is an image");
+  for (int step = 0; step < num_steps; step++) {
+    image.StartSampling();
+    for (int i = 0; i < 7; i++) {
+      vector<int64_t> shape({5, 5, 3});
+      vector<float> data;
+      for (int j = 0; j < 3 * 5 * 5; j++) {
+        data.push_back(float(rand()) / RAND_MAX);
+      }
+      image.AddSample(shape, data);
+    }
+    image.FinishSampling();
+  }
+
+  LOG(INFO) << "read images";
+  // read it
+  LogReader reader__(dir);
+  auto reader = reader__.AsMode("train");
+  auto tablet2read = reader.tablet("image0");
+  components::ImageReader image2read("train", tablet2read);
+  CHECK_EQ(image2read.caption(), "this is an image");
+  CHECK_EQ(image2read.num_records(), num_steps);
+}
+
 TEST(Histogram, AddRecord) {
   const auto dir = "./tmp/sdk_test.histogram";
   LogWriter writer__(dir, 1);

visualdl/python/test_storage.py

@@ -13,8 +13,7 @@ from visualdl import LogWriter, LogReader
 class StorageTest(unittest.TestCase):
     def setUp(self):
         self.dir = "./tmp/storage_test"
-        self.writer = LogWriter(
-            self.dir, sync_cycle=1).as_mode("train")
+        self.writer = LogWriter(self.dir, sync_cycle=1).as_mode("train")
 
     def test_scalar(self):
         print 'test write'
@@ -30,7 +29,8 @@ class StorageTest(unittest.TestCase):
             self.assertEqual(scalar.caption(), "train")
             records = scalar.records()
             ids = scalar.ids()
-            self.assertTrue(np.equal(records, [float(i) for i in range(10)]).all())
+            self.assertTrue(
+                np.equal(records, [float(i) for i in range(10)]).all())
             self.assertTrue(np.equal(ids, [float(i) for i in range(10)]).all())
             print 'records', records
             print 'ids', ids
@@ -45,11 +45,9 @@ class StorageTest(unittest.TestCase):
         for pass_ in xrange(num_passes):
             image_writer.start_sampling()
             for ins in xrange(num_samples):
-                index = image_writer.is_sample_taken()
-                if index != -1:
-                    data = np.random.random(shape) * 256
-                    data = np.ndarray.flatten(data)
-                    image_writer.set_sample(index, shape, list(data))
+                data = np.random.random(shape) * 256
+                data = np.ndarray.flatten(data)
+                image_writer.add_sample(shape, list(data))
             image_writer.finish_sampling()
 
         self.reader = LogReader(self.dir)
@@ -88,7 +86,6 @@ class StorageTest(unittest.TestCase):
             image_writer.finish_sampling()
 
             # read and check whether the original image will be displayed
-
             image_reader = reader.image(tag)
             image_record = image_reader.record(0, 0)
             data = image_record.data()
@@ -102,10 +99,6 @@ class StorageTest(unittest.TestCase):
             # manully check the image and found that nothing wrong with the image storage.
             # image.show()
 
-            # after scale, elements are changed.
-            # self.assertTrue(
-            #     np.equal(origin_data.reshape(PIL_image_shape), data).all())
-
     def test_with_syntax(self):
         with self.writer.mode("train") as writer:
             scalar = writer.scalar("model/scalar/average")
@@ -118,8 +111,7 @@ class StorageTest(unittest.TestCase):
             self.assertEqual(scalar.caption(), "train")
 
     def test_modes(self):
-        store = LogWriter(
-            self.dir, sync_cycle=1)
+        store = LogWriter(self.dir, sync_cycle=1)
 
         scalars = []
 
@@ -133,6 +125,5 @@ class StorageTest(unittest.TestCase):
                 scalar.add_record(i, float(i))
 
 
-
 if __name__ == '__main__':
     unittest.main()

visualdl/server/storage_mock.py

@@ -26,13 +26,9 @@ def add_image(writer,
         for pass_ in xrange(num_passes):
             image_writer.start_sampling()
             for ins in xrange(2 * num_samples):
-                index = image_writer.is_sample_taken()
-                if index != -1:
-                    data = np.random.random(shape) * 256
-                    data = np.ndarray.flatten(data)
-                    assert shape
-                    assert len(data) > 0
-                    image_writer.set_sample(index, shape, list(data))
+                data = np.random.random(shape) * 256
+                data = np.ndarray.flatten(data)
+                image_writer.add_sample(shape, list(data))
             image_writer.finish_sampling()