From 09d910191e986c2fa0477b7274669c24d721f3c7 Mon Sep 17 00:00:00 2001
From: =?utf8?q?=EC=9C=A4=ED=98=84=EC=8B=9D/=EB=8F=99=EC=9E=91=EC=A0=9C?=
 =?utf8?q?=EC=96=B4Lab=28SR=29/Principal=20Engineer/=EC=82=BC=EC=84=B1?=
 =?utf8?q?=EC=A0=84=EC=9E=90?= <hyunsik.yoon@samsung.com>
Date: Tue, 27 Nov 2018 11:40:08 +0900
Subject: [PATCH] [enco/tfl/frontend] Padding when top == bottom -1 or left =
 right-1 (#2411)

* [enco/tfl/frontend] Padding when top == bottom -1 or left = right-1

get_padding() now calculates padding when top == bottom -1 or left = right-1

Signed-off-by: Hyun Sik Yoon <hyunsik.yoon@samsung.com>

* pr fix: calculate -> compute, ifm -> in_size
---
 contrib/enco/frontend/tflite/src/Op/Padding.cpp | 31 ++++++++++++-----
 contrib/enco/test/tflite/Conv2D_004/INFERENCE   |  0
 contrib/enco/test/tflite/Conv2D_004/test.recipe | 45 +++++++++++++++++++++++++
 3 files changed, 67 insertions(+), 9 deletions(-)
 create mode 100644 contrib/enco/test/tflite/Conv2D_004/INFERENCE
 create mode 100644 contrib/enco/test/tflite/Conv2D_004/test.recipe

diff --git a/contrib/enco/frontend/tflite/src/Op/Padding.cpp b/contrib/enco/frontend/tflite/src/Op/Padding.cpp
index 7edaee9..5c2b5f7 100644
--- a/contrib/enco/frontend/tflite/src/Op/Padding.cpp
+++ b/contrib/enco/frontend/tflite/src/Op/Padding.cpp
@@ -27,6 +27,7 @@
 
 #include <map>
 #include <sstream>
+#include <algorithm>
 
 using namespace nncc::core::ADT;
 
@@ -39,17 +40,28 @@ coco::Padding2D get_padding(const tensor::Shape &ifm_shape, const int kernel_w,
 {
   assert(ifm_shape.rank() == 4);
 
+  /**
+   * Compute [top padding + bottom padding] (or [left padding + right padding]).
+   * If this returns an even number, top = return value / 2 and bottom = return value - top
+   * If this returns an odd number, top = return value / 2 and bottom = return value - top (so,
+   * bottom = top + 1)
+   *
+   * Code based on https://www.tensorflow.org/api_guides/python/nn#Convolution
+   */
   auto compute_padding = [](tflite::Padding padding, int stride, int dilation_rate, int in_size,
                             int filter_size) {
-    // code from tensorflow lite 1.9
     int effective_filter_size = (filter_size - 1) * dilation_rate + 1;
-    int out_size = (padding == tflite::Padding_SAME)
-                       ? (in_size + stride - 1) / stride
-                       : (padding == tflite::Padding_VALID)
-                             ? (in_size - effective_filter_size + stride) / stride
-                             : 0;
-    int value = ((out_size - 1) * stride + effective_filter_size - in_size) / 2;
-    return value > 0 ? value : 0;
+    if (padding == tflite::Padding_SAME)
+    {
+      if (in_size % stride == 0)
+        return std::max(effective_filter_size - stride, 0);
+      else
+        return std::max(effective_filter_size - (in_size % stride), 0);
+    }
+    else // padding == VALID
+    {
+      return 0;
+    }
   };
 
   // ifm shape is from order of NHWC. ifm W = dim(2), ifm H = dim(1)
@@ -57,7 +69,8 @@ coco::Padding2D get_padding(const tensor::Shape &ifm_shape, const int kernel_w,
   int padding_h = compute_padding(padding, stride_h, dilation_h_factor, ifm_shape.dim(1), kernel_h);
 
   coco::Padding2D coco_padding;
-  coco_padding.top(padding_h).bottom(padding_h).left(padding_w).right(padding_w);
+  coco_padding.top(padding_h / 2).bottom(padding_h - padding_h / 2);
+  coco_padding.left(padding_w / 2).right(padding_w - padding_w / 2);
 
   return coco_padding;
 }
diff --git a/contrib/enco/test/tflite/Conv2D_004/INFERENCE b/contrib/enco/test/tflite/Conv2D_004/INFERENCE
new file mode 100644
index 0000000..e69de29
diff --git a/contrib/enco/test/tflite/Conv2D_004/test.recipe b/contrib/enco/test/tflite/Conv2D_004/test.recipe
new file mode 100644
index 0000000..20f4a99
--- /dev/null
+++ b/contrib/enco/test/tflite/Conv2D_004/test.recipe
@@ -0,0 +1,45 @@
+# Conv2D with ifm w, h = 14, 14 && ofm w, h = 7, 7 && stride = 2, 2 && padding = SAME (similar case from Mobile)
+operand {
+  name: "ifm"
+  type: FLOAT32
+  shape { dim: 1 dim: 14 dim: 14 dim: 2 }
+}
+operand {
+  name: "ker"
+  type: FLOAT32
+  shape { dim: 1 dim: 3 dim: 3 dim: 2 }
+  filler {
+    tag: "gaussian"
+    arg: "0.0"
+    arg: "1.0"
+  }
+}
+operand {
+  name: "bias"
+  type: FLOAT32
+  shape { dim: 1 }
+  filler {
+    tag: "gaussian"
+    arg: "0.0"
+    arg: "1.0"
+  }
+}
+operand {
+  name: "ofm"
+  type: FLOAT32
+  shape { dim: 1 dim: 7 dim: 7 dim: 1 }
+}
+operation {
+  type: "Conv2D"
+  conv2d_options {
+    padding: SAME
+    stride_w: 2
+    stride_h: 2
+  }
+  input: "ifm"
+  input: "ker"
+  input: "bias"
+  output: "ofm"
+}
+input: "ifm"
+output: "ofm"
-- 
2.7.4