libavfilter/dnn_native: Add multiple activation functions in dnn native

Add "Leaky_relu" and "None" option in activation function.
Reviewed-by: Guo, Yejun <yejun.guo@intel.com>
Signed-off-by: Xuewei Meng <xwmeng96@gmail.com>
Signed-off-by: Steven Liu <lq@onvideo.cn>

libavfilter/dnn_backend_native.c

@@ -270,6 +270,11 @@ static void convolve(const float *input, float *output, const ConvolutionalParam
                     break;
                 case SIGMOID:
                     output[n_filter] = 1.0f / (1.0f + exp(-output[n_filter]));
+                    break;
+                case NONE:
+                    break;
+                case LEAKY_RELU:
+                    output[n_filter] = FFMAX(output[n_filter], 0.0) + 0.2 * FFMIN(output[n_filter], 0.0);
                 }
             }
             output += conv_params->output_num;

libavfilter/dnn_backend_native.h

@@ -32,7 +32,7 @@
 
 typedef enum {INPUT, CONV, DEPTH_TO_SPACE} DNNLayerType;
 
-typedef enum {RELU, TANH, SIGMOID} DNNActivationFunc;
+typedef enum {RELU, TANH, SIGMOID, NONE, LEAKY_RELU} DNNActivationFunc;
 
 typedef enum {VALID, SAME, SAME_CLAMP_TO_EDGE} DNNConvPaddingParam;