解决keras模式下，使用GPU训练时会爆显存的bug。

src/TensorFlowNET.Core/APIs/tf.image.cs

@@ -339,6 +339,13 @@ public Tensor decode_image(Tensor contents, int channels = 0, TF_DataType dtype
                 => image_ops_impl.decode_image(contents, channels: channels, dtype: dtype,
                     name: name, expand_animations: expand_animations);
 
+            public Tensor encode_png(Tensor contents, string name = null)
+                    => image_ops_impl.encode_png(contents, name: name);
+
+            public Tensor encode_jpeg(Tensor contents, string name = null)
+                    => image_ops_impl.encode_jpeg(contents, name: name);
+
+
             /// <summary>
             /// Convenience function to check if the 'contents' encodes a JPEG image.
             /// </summary>

src/TensorFlowNET.Core/APIs/tf.io.cs

@@ -16,6 +16,7 @@ limitations under the License.
 
 using System.Collections.Generic;
 using Tensorflow.IO;
+using Tensorflow.Operations;
 
 namespace Tensorflow
 {
@@ -46,6 +47,12 @@ public Operation save_v2(Tensor prefix, string[] tensor_names,
             public Tensor[] restore_v2(Tensor prefix, string[] tensor_names,
                 string[] shape_and_slices, TF_DataType[] dtypes, string name = null)
                 => ops.restore_v2(prefix, tensor_names, shape_and_slices, dtypes, name: name);
+
+            public Operation write_file(string filename, Tensor conentes, string name = null)
+                => write_file(Tensorflow.ops.convert_to_tensor(filename, TF_DataType.TF_STRING), conentes, name);
+
+            public Operation write_file(Tensor filename, Tensor conentes, string name = null)
+                => gen_ops.write_file(filename, conentes, name);
         }
 
         public GFile gfile = new GFile();

src/TensorFlowNET.Core/Eager/EagerRunner.RecordGradient.cs

@@ -80,6 +80,11 @@ BackwardFunction GetGradientFunction(string op_name,
                      Tensor[] op_outputs)
             => (out_grads, unneeded_gradients) =>
             {
+                if(!ops.gradientFunctions.ContainsKey(op_name))
+                {
+                    throw new Exception($"gradientFunctions not find op_name: {op_name}");
+                }
+
                 if (ops.gradientFunctions[op_name] == null)
                     return new Tensor[op_inputs.Length];
 

src/TensorFlowNET.Core/Gradients/nn_grad.cs

@@ -229,6 +229,37 @@ public static Tensor[] _Conv2DGrad(Operation op, Tensor[] grads)
             };
         }
 
+        /// <summary>
+        /// Gradient function for Conv2D.
+        /// </summary>
+        /// <param name="op"></param>
+        /// <param name="grads"></param>
+        /// <returns></returns>
+        [RegisterGradient("DepthwiseConv2dNative")]
+        public static Tensor[] _DepthwiseConv2DGrad(Operation op, Tensor[] grads)
+        {
+            var dilations = op.get_attr_list<int>("dilations");
+            var strides = op.get_attr_list<int>("strides");
+            var padding = op.get_attr<string>("padding");
+            var explicit_paddings = op.get_attr_list<int>("explicit_paddings");
+            var data_format = op.get_attr<string>("data_format");
+            var shape = gen_array_ops.shape_n(new Tensor[] { op.inputs[0], op.inputs[1] });
+
+            return new Tensor[]
+            {
+                gen_nn_ops.depthwise_conv2d_native_backprop_input(
+                    shape[0], op.inputs[1], grads[0],
+                    strides, padding, explicit_paddings,
+                    dilations: dilations,
+                    data_format: data_format),
+                gen_nn_ops.depthwise_conv2d_native_backprop_filter(op.inputs[0], shape[1], grads[0],
+                    strides, padding,
+                    dilations: dilations,
+                    explicit_paddings: explicit_paddings,                    
+                    data_format: data_format)
+            };
+        }
+
         [RegisterGradient("FusedBatchNorm")]
         public static Tensor[] _FusedBatchNormGrad(Operation op, Tensor[] grads)
             => _BaseFusedBatchNormGrad(op, 0, grads);

src/TensorFlowNET.Core/Keras/Engine/IModel.cs

@@ -24,6 +24,7 @@ ICallback fit(NDArray x, NDArray y,
             List<ICallback> callbacks = null,
             float validation_split = 0f,
             ValidationDataPack validation_data = null,
+            int validation_step = 10,
             bool shuffle = true,
             Dictionary<int, float> class_weight = null,
             NDArray sample_weight = null,
@@ -47,6 +48,20 @@ ICallback fit(IEnumerable<NDArray> x, NDArray y,
             int workers = 1,
             bool use_multiprocessing = false);
 
+    public ICallback fit(IDatasetV2 dataset,
+            int batch_size = -1,
+            int epochs = 1,
+            int verbose = 1,
+            List<ICallback> callbacks = null,
+            IDatasetV2 validation_data = null,
+            int validation_step = 10,   // 间隔多少次会进行一次验证
+            bool shuffle = true,
+            Dictionary<int, float> class_weight = null,
+            int initial_epoch = 0,
+            int max_queue_size = 10,
+            int workers = 1,
+            bool use_multiprocessing = false);
+
     void save(string filepath,
             bool overwrite = true,
             bool include_optimizer = true,
@@ -85,6 +100,14 @@ Tensors predict(Tensors x,
             int workers = 1,
             bool use_multiprocessing = false);
 
+    public Tensors predict(IDatasetV2 dataset,
+            int batch_size = -1,
+            int verbose = 0,
+            int steps = -1,
+            int max_queue_size = 10,
+            int workers = 1,
+            bool use_multiprocessing = false);
+
     void summary(int line_length = -1, float[] positions = null);
 
     IKerasConfig get_config();

src/TensorFlowNET.Core/Keras/Layers/ILayersApi.cs

@@ -55,6 +55,12 @@ public ILayer Conv1D(int filters,
             string kernel_initializer = "glorot_uniform",
             string bias_initializer = "zeros");
 
+        public ILayer Conv2D(int filters,
+                Shape kernel_size = null,
+                Shape strides = null,
+                string padding = "valid"
+            );
+
         public ILayer Conv2D(int filters,
             Shape kernel_size = null,
             Shape strides = null,
@@ -95,6 +101,19 @@ public ILayer Conv2D(int filters,
             bool use_bias = true,
             string kernel_initializer = "glorot_uniform",
             string bias_initializer = "zeros");
+        public ILayer DepthwiseConv2D(Shape kernel_size = null,
+            Shape strides = null,
+            string padding = "valid",
+            string data_format = null,
+            Shape dilation_rate = null,
+            int groups = 1,
+            int depth_multiplier = 1,
+            string activation = null,
+            bool use_bias = false,
+            string kernel_initializer = "glorot_uniform",
+            string bias_initializer = "zeros",
+            string depthwise_initializer = "glorot_uniform"
+            );
 
         public ILayer Dense(int units);
         public ILayer Dense(int units,

src/TensorFlowNET.Core/Operations/image_ops_impl.cs

@@ -102,7 +102,10 @@ internal static Operation[] _CheckAtLeast3DImage(Tensor image, bool require_stat
             {
                 throw new ValueError("\'image\' must be fully defined.");
             }
-            var dims = image_shape["-3:"];
+            var dims = new Shape(new[] {
+                                image_shape.dims[image_shape.dims.Length - 3],
+                                image_shape.dims[image_shape.dims.Length - 2],
+                                image_shape.dims[image_shape.dims.Length - 1]});
             foreach (var dim in dims.dims)
             {
                 if (dim == 0)
@@ -112,16 +115,18 @@ internal static Operation[] _CheckAtLeast3DImage(Tensor image, bool require_stat
             }
 
             var image_shape_last_three_elements = new Shape(new[] {
-                                                image_shape.dims[image_shape.dims.Length - 1],
+                                                image_shape.dims[image_shape.dims.Length - 3],
                                                 image_shape.dims[image_shape.dims.Length - 2],
-                                                image_shape.dims[image_shape.dims.Length - 3]});
+                                                image_shape.dims[image_shape.dims.Length - 1]});
             if (!image_shape_last_three_elements.IsFullyDefined)
             {
                 Tensor image_shape_ = array_ops.shape(image);
-                var image_shape_return = tf.constant(new[] {
-                    image_shape_.dims[image_shape.dims.Length - 1],
-                    image_shape_.dims[image_shape.dims.Length - 2],
-                    image_shape_.dims[image_shape.dims.Length - 3]});
+                var image_shape_return = tf.slice(image_shape_, new[] { Math.Max(image_shape.dims.Length - 3, 0) }, new[] { 3 });
+
+                //var image_shape_return = tf.constant(new[] {
+                //    image_shape_.dims[image_shape_.dims.Length - 3],
+                //    image_shape_.dims[image_shape_.dims.Length - 2],
+                //    image_shape_.dims[image_shape_.dims.Length - 1]});
 
                 return new Operation[] {
                     check_ops.assert_positive(
@@ -209,10 +214,10 @@ internal static Tensor _random_flip(Tensor image, int flip_index, int seed, stri
         }
 
         public static Tensor flip_left_right(Tensor image)
-            => _flip(image, 0, "flip_left_right");
+            => _flip(image, 1, "flip_left_right");
 
         public static Tensor flip_up_down(Tensor image)
-            => _flip(image, 1, "flip_up_down");
+            => _flip(image, 0, "flip_up_down");
 
         internal static Tensor _flip(Tensor image, int flip_index, string scope_name)
         {
@@ -223,11 +228,11 @@ internal static Tensor _flip(Tensor image, int flip_index, string scope_name)
                   Shape shape = image.shape;
                   if (shape.ndim == 3 || shape.ndim == Unknown)
                   {
-                      return fix_image_flip_shape(image, gen_array_ops.reverse(image, ops.convert_to_tensor(new int[] { flip_index })));
+                      return fix_image_flip_shape(image, gen_array_ops.reverse_v2(image, ops.convert_to_tensor(new int[] { flip_index })));
                   }
                   else if (shape.ndim == 4)
                   {
-                      return gen_array_ops.reverse_v2(image, ops.convert_to_tensor(new[] { (flip_index + 1) % 2 }));
+                      return gen_array_ops.reverse_v2(image, ops.convert_to_tensor(new[] { flip_index + 1 }));
                   }
                   else
                   {
@@ -2047,6 +2052,22 @@ internal static (Tensor, Tensor) non_max_suppression_padded_v1(Tensor boxes, Ten
             });
         }
 
+        public static Tensor encode_jpeg(Tensor contents, string name = null)
+        {
+            return tf_with(ops.name_scope(name, "encode_jpeg"), scope =>
+            {
+                return gen_ops.encode_jpeg(contents, name:name);
+            });
+        }
+
+        public static Tensor encode_png(Tensor contents, string name = null)
+        {
+            return tf_with(ops.name_scope(name, "encode_png"), scope =>
+            {
+                return gen_ops.encode_png(contents, name: name);
+            });
+        }
+
         public static Tensor is_jpeg(Tensor contents, string name = null)
         {
             return tf_with(ops.name_scope(name, "is_jpeg"), scope =>

src/TensorFlowNET.Core/Tensors/tensor_util.cs

@@ -249,6 +249,9 @@ public static TensorProto make_tensor_proto(object values, TF_DataType dtype = T
                     case sbyte val:
                         tensor_proto.IntVal.AddRange(new[] { (int)val });
                         break;
+                    case byte val:
+                        tensor_proto.IntVal.AddRange(new[] { (int)val });
+                        break;
                     case int val:
                         tensor_proto.IntVal.AddRange(new[] { val });
                         break;
@@ -262,7 +265,7 @@ public static TensorProto make_tensor_proto(object values, TF_DataType dtype = T
                         tensor_proto.DoubleVal.AddRange(new[] { val });
                         break;
                     default:
-                        throw new Exception("make_tensor_proto Not Implemented");
+                        throw new Exception($"make_tensor_proto Not Implemented {values.GetType().Name}");
                 }
             }
 

src/TensorFlowNET.Keras/Engine/Model.Evaluate.cs

@@ -132,6 +132,7 @@ Dictionary<string, float> evaluate(DataHandler data_handler, CallbackList callba
                     var end_step = step + data_handler.StepIncrement;
                     if (!is_val)
                         callbacks.on_test_batch_end(end_step, logs);
+                    GC.Collect();
                 }
             }
             callbacks.on_test_end(logs);
@@ -167,7 +168,9 @@ Dictionary<string, float> test_step_multi_inputs_function(DataHandler data_handl
         Dictionary<string, float> test_step(DataHandler data_handler, Tensors x, Tensors y)
         {
             (x,y) = data_handler.DataAdapter.Expand1d(x, y);
+
             var y_pred = Apply(x, training: false);
+
             var loss = compiled_loss.Call(y, y_pred);
             compiled_metrics.update_state(y, y_pred);
             return metrics.Select(x => (x.Name, x.result())).ToDictionary(x => x.Item1, x => (float)x.Item2);

src/TensorFlowNET.Keras/Engine/Model.Fit.cs

@@ -41,6 +41,7 @@ public ICallback fit(NDArray x, NDArray y,
             List<ICallback> callbacks = null,
             float validation_split = 0f,
             ValidationDataPack validation_data = null,
+            int validation_step = 10,
             bool shuffle = true,
             Dictionary<int, float> class_weight = null,
             NDArray sample_weight = null,
@@ -147,7 +148,7 @@ public ICallback fit(IEnumerable<NDArray> x, NDArray y,
             }
         }
 
-        public History fit(IDatasetV2 dataset, 
+        public ICallback fit(IDatasetV2 dataset, 
             int batch_size = -1,
             int epochs = 1,
             int verbose = 1,
@@ -156,7 +157,6 @@ public History fit(IDatasetV2 dataset,
             int validation_step = 10,
             bool shuffle = true,
             Dictionary<int, float> class_weight = null,
-            NDArray sample_weight = null,
             int initial_epoch = 0,
             int max_queue_size = 10,
             int workers = 1,
@@ -170,7 +170,7 @@ public History fit(IDatasetV2 dataset,
                 InitialEpoch = initial_epoch,
                 Epochs = epochs,
                 Shuffle = shuffle,
-                SampleWeight = sample_weight,
+                ClassWeight = class_weight,
                 MaxQueueSize = max_queue_size,
                 Workers = workers,
                 UseMultiprocessing = use_multiprocessing,
@@ -218,6 +218,7 @@ History FitInternal(DataHandler data_handler, int epochs, int validation_step, i
                     var end_step = step + data_handler.StepIncrement;
                     End_step = end_step;
                     callbacks.on_train_batch_end(end_step, logs);
+                    GC.Collect();
                 }
 
                 if (validation_data != null)
@@ -233,11 +234,10 @@ History FitInternal(DataHandler data_handler, int epochs, int validation_step, i
                     callbacks.on_train_batch_end(End_step, logs);
                 }
 
+                GC.Collect();
 
                 callbacks.on_epoch_end(epoch, logs);
 
-                GC.Collect();
-                GC.WaitForPendingFinalizers();
                 if (stop_training)
                 {
                     break;
@@ -282,6 +282,7 @@ History FitInternal(DataHandler data_handler, int epochs, int verbose, List<ICal
                     var end_step = step + data_handler.StepIncrement;
                     End_step = end_step;
                     callbacks.on_train_batch_end(end_step, logs);
+                    GC.Collect();
                 }
 
                 if (validation_data != null)
@@ -301,7 +302,6 @@ History FitInternal(DataHandler data_handler, int epochs, int verbose, List<ICal
                 callbacks.on_epoch_end(epoch, logs);
 
                 GC.Collect();
-                GC.WaitForPendingFinalizers();
                 if (stop_training)
                 {
                     break;

src/TensorFlowNET.Keras/Engine/Model.Predict.cs

@@ -102,9 +102,9 @@ Tensors PredictInternal(DataHandler data_handler, int verbose)
                         for (int i = 0; i < batch_outputs.Length; i++)
                             batch_outputs[i] = tf.concat(new Tensor[] { batch_outputs[i], tmp_batch_outputs[i] }, axis: 0);
                     }
-
                     var end_step = step + data_handler.StepIncrement;
                     callbacks.on_predict_batch_end(end_step, new Dictionary<string, Tensors> { { "outputs", batch_outputs } });
+                    GC.Collect();
                 }
             }