COMPMID-661: Fix scale border issue (#38)

Change-Id: If1dcca724e5e5f5ab363ffc16b0ef8c943e0b657
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/110105
Tested-by: BSG Visual Compute Jenkins server to access repositories on http://mpd-gerrit.cambridge.arm.com <bsgcomp@arm.com>
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>

3 files changed, 29 insertions, 19 deletions

diff --git a/arm_compute/core/CL/kernels/CLScaleKernel.h b/arm_compute/core/CL/kernels/CLScaleKernel.h
index db0587d6ac..3bca6efd0a 100644
--- a/arm_compute/core/CL/kernels/CLScaleKernel.h
+++ b/arm_compute/core/CL/kernels/CLScaleKernel.h
@@ -42,8 +42,9 @@ public:
      *                              All but the lowest two dimensions must be the same size as in the input tensor, i.e. scaling is only performed within the XY-plane.
      * @param[in]  policy           Interpolation type to use
      * @param[in]  border_undefined True if the border mode is undefined. False if it's replicate or constant.
+     * @param[in]  sampling_policy  (Optional) Sampling policy used by the interpolation. Defaults to @ref SamplingPolicy::CENTER
      */
-    void configure(const ICLTensor *input, ICLTensor *output, InterpolationPolicy policy, bool border_undefined);
+    void configure(const ICLTensor *input, ICLTensor *output, InterpolationPolicy policy, bool border_undefined, SamplingPolicy sampling_policy = SamplingPolicy::CENTER);
 
     // Inherited methods overridden:
     BorderSize border_size() const override;
diff --git a/arm_compute/core/NEON/kernels/NEScaleKernel.h b/arm_compute/core/NEON/kernels/NEScaleKernel.h
index 5ec5854841..ac154d4455 100644
--- a/arm_compute/core/NEON/kernels/NEScaleKernel.h
+++ b/arm_compute/core/NEON/kernels/NEScaleKernel.h
@@ -59,8 +59,10 @@ public:
      * @param[out] output           Destination tensor. Data types supported: Same as @p input. All but the lowest two dimensions must be the same size as in the input tensor, i.e. scaling is only performed within the XY-plane.
      * @param[in]  policy           Interpolation type to use
      * @param[in]  border_undefined True if the border mode is undefined. False if it's replicate or constant.
+     * @param[in]  sampling_policy  (Optional) Sampling policy used by the interpolation. Defaults to @ref SamplingPolicy::CENTER
      */
-    void configure(const ITensor *input, const ITensor *dx, const ITensor *dy, const ITensor *offsets, ITensor *output, InterpolationPolicy policy, bool border_undefined);
+    void configure(const ITensor *input, const ITensor *dx, const ITensor *dy, const ITensor *offsets, ITensor *output, InterpolationPolicy policy, bool border_undefined,
+                   SamplingPolicy sampling_policy = SamplingPolicy::CENTER);
 
     // Inherited methods overridden:
     void run(const Window &window, const ThreadInfo &info) override;
diff --git a/arm_compute/core/Types.h b/arm_compute/core/Types.h
index 37f8508674..4ecaec1eb9 100644
--- a/arm_compute/core/Types.h
+++ b/arm_compute/core/Types.h
@@ -41,23 +41,23 @@ using half = half_float::half;
 /** Image colour formats */
 enum class Format
 {
-    UNKNOWN,  /** Unknown image format */
-    U8,       /** 1 channel, 1 U8 per channel */
-    S16,      /** 1 channel, 1 S16 per channel */
-    U16,      /** 1 channel, 1 U16 per channel */
-    S32,      /** 1 channel, 1 S32 per channel */
-    U32,      /** 1 channel, 1 U32 per channel */
-    F16,      /** 1 channel, 1 F16 per channel */
-    F32,      /** 1 channel, 1 F32 per channel */
-    UV88,     /** 2 channel, 1 U8 per channel */
-    RGB888,   /** 3 channels, 1 U8 per channel */
-    RGBA8888, /** 4 channels, 1 U8 per channel */
-    YUV444,   /** A 3 plane of 8 bit 4:4:4 sampled Y, U, V planes */
-    YUYV422,  /** A single plane of 32-bit macro pixel of Y0, U0, Y1, V0 bytes */
-    NV12,     /** A 2 plane YUV format of Luma (Y) and interleaved UV data at 4:2:0 sampling */
-    NV21,     /** A 2 plane YUV format of Luma (Y) and interleaved VU data at 4:2:0 sampling */
-    IYUV,     /** A 3 plane of 8-bit 4:2:0 sampled Y, U, V planes */
-    UYVY422   /** A single plane of 32-bit macro pixel of U0, Y0, V0, Y1 byte */
+    UNKNOWN,  /**< Unknown image format */
+    U8,       /**< 1 channel, 1 U8 per channel */
+    S16,      /**< 1 channel, 1 S16 per channel */
+    U16,      /**< 1 channel, 1 U16 per channel */
+    S32,      /**< 1 channel, 1 S32 per channel */
+    U32,      /**< 1 channel, 1 U32 per channel */
+    F16,      /**< 1 channel, 1 F16 per channel */
+    F32,      /**< 1 channel, 1 F32 per channel */
+    UV88,     /**< 2 channel, 1 U8 per channel */
+    RGB888,   /**< 3 channels, 1 U8 per channel */
+    RGBA8888, /**< 4 channels, 1 U8 per channel */
+    YUV444,   /**< A 3 plane of 8 bit 4:4:4 sampled Y, U, V planes */
+    YUYV422,  /**< A single plane of 32-bit macro pixel of Y0, U0, Y1, V0 bytes */
+    NV12,     /**< A 2 plane YUV format of Luma (Y) and interleaved UV data at 4:2:0 sampling */
+    NV21,     /**< A 2 plane YUV format of Luma (Y) and interleaved VU data at 4:2:0 sampling */
+    IYUV,     /**< A 3 plane of 8-bit 4:2:0 sampled Y, U, V planes */
+    UYVY422   /**< A single plane of 32-bit macro pixel of U0, Y0, V0, Y1 byte */
 };
 
 /** Available data types */
@@ -82,6 +82,13 @@ enum class DataType
     SIZET
 };
 
+/** Available Sampling Policies */
+enum class SamplingPolicy
+{
+    CENTER,  /**< Samples are taken at pixel center */
+    TOP_LEFT /**< Samples are taken at pixel top left corner */
+};
+
 /** Constant value of the border pixels when using BorderMode::CONSTANT */
 constexpr uint8_t CONSTANT_BORDER_VALUE = 199;