.. _program_listing_file__tmp_ws_src_vitis_common_include_imgproc_xf_histogram.hpp:

Program Listing for File xf_histogram.hpp
=========================================

|exhale_lsh| :ref:`Return to documentation for file <file__tmp_ws_src_vitis_common_include_imgproc_xf_histogram.hpp>` (``/tmp/ws/src/vitis_common/include/imgproc/xf_histogram.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   /*
    * Copyright 2019 Xilinx, Inc.
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *     http://www.apache.org/licenses/LICENSE-2.0
    *
    * Unless required by applicable law or agreed to in writing, software
    * distributed under the License is distributed on an "AS IS" BASIS,
    * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    * See the License for the specific language governing permissions and
    * limitations under the License.
    */
   
   #ifndef _XF_HISTOGRAM_HPP_
   #define _XF_HISTOGRAM_HPP_
   
   #ifndef __cplusplus
   #error C++ is needed to include this header
   #endif
   
   #include "../common/xf_common.hpp"
   #include "hls_stream.h"
   namespace xf {
   namespace cv {
   
   template <int SRC_T, int ROWS, int COLS, int DEPTH, int NPC, int WORDWIDTH, int SRC_TC, int PLANES>
   void xFHistogramKernel(xf::cv::Mat<SRC_T, ROWS, COLS, NPC>& _src_mat,
                          uint32_t hist_array[PLANES][256],
                          uint16_t& imgheight,
                          uint16_t& imgwidth) {
       // Temporary array used while computing histogram
       uint32_t tmp_hist[(PLANES << XF_BITSHIFT(NPC))][256];
       uint32_t tmp_hist1[(PLANES << XF_BITSHIFT(NPC))][256];
   // clang-format off
   #pragma HLS ARRAY_PARTITION variable=tmp_hist complete dim=1
   #pragma HLS ARRAY_PARTITION variable=tmp_hist1 complete dim=1
       // clang-format on
       XF_SNAME(WORDWIDTH) in_buf, in_buf1, temp_buf;
   
       bool flag = 0;
   
   HIST_INITIALIZE_LOOP:
       for (ap_uint<10> i = 0; i < 256; i++) //
       {
   // clang-format off
   #pragma HLS PIPELINE
           // clang-format on
           for (ap_uint<5> j = 0; j < (1 << XF_BITSHIFT(NPC) * PLANES); j++) {
   // clang-format off
   #pragma HLS LOOP_TRIPCOUNT min=256 max=256
               // clang-format on
               tmp_hist[j][i] = 0;
               tmp_hist1[j][i] = 0;
           }
       }
   
   HISTOGRAM_ROW_LOOP:
       for (ap_uint<13> row = 0; row < imgheight; row++) {
   // clang-format off
   #pragma HLS LOOP_TRIPCOUNT min=ROWS max=ROWS
       // clang-format on
       HISTOGRAM_COL_LOOP:
           for (ap_uint<13> col = 0; col < (imgwidth); col = col + 2) {
   // clang-format off
   #pragma HLS PIPELINE II=2
   #pragma HLS LOOP_FLATTEN OFF
   #pragma HLS LOOP_TRIPCOUNT min=SRC_TC max=SRC_TC
               // clang-format on
               in_buf = _src_mat.read(row * (imgwidth) + col); //.data[row*(imgwidth) + col];
   
               if (col == (imgwidth - 1))
                   in_buf1 = 0;
               else
                   in_buf1 = _src_mat.read(row * (imgwidth) + col + 1); //.data[row*(imgwidth) + col+1];
   
           EXTRACT_UPDATE:
               for (ap_uint<9> i = 0, j = 0; i < ((8 << XF_BITSHIFT(NPC)) * PLANES); j++, i += 8) {
   // clang-format off
   #pragma HLS DEPENDENCE variable=tmp_hist array intra false
   #pragma HLS DEPENDENCE variable=tmp_hist1 array intra false
   #pragma HLS UNROLL
                   // clang-format on
   
                   ap_uint<8> val = 0, val1 = 0;
                   val = in_buf.range(i + 7, i);
                   val1 = in_buf1.range(i + 7, i);
   
                   uint32_t tmpval = tmp_hist[j][val];
                   uint32_t tmpval1 = tmp_hist1[j][val1];
                   tmp_hist[j][val] = tmpval + 1;
                   if (!(col == (imgwidth - 1))) tmp_hist1[j][val1] = tmpval1 + 1;
               }
           }
       }
   
       const int num_ch = XF_CHANNELS(SRC_T, NPC);
   
   MERGE_HIST_LOOP:
       for (ap_uint<32> i = 0; i < 256; i++) {
   // clang-format off
   #pragma HLS pipeline
       // clang-format on
   
       MERGE_HIST_CH_UNROLL:
           for (ap_uint<5> ch = 0; ch < num_ch; ch++) {
   // clang-format off
   #pragma HLS UNROLL
               // clang-format on
   
               uint32_t value = 0;
   
           MERGE_HIST_NPPC_UNROLL:
               for (ap_uint<5> p = 0; p < XF_NPIXPERCYCLE(NPC); p++) {
   // clang-format off
   #pragma HLS UNROLL
                   // clang-format on
                   value += tmp_hist[p * num_ch + ch][i] + tmp_hist1[p * num_ch + ch][i];
               }
   
               hist_array[ch][i] = value;
           }
       }
   }
   
   template <int SRC_T, int ROWS, int COLS, int NPC = 1>
   void calcHist(xf::cv::Mat<SRC_T, ROWS, COLS, NPC>& _src, uint32_t* histogram) {
   #ifndef __SYNTHESIS__
       assert(((NPC == XF_NPPC1) || (NPC == XF_NPPC8)) && "NPC must be XF_NPPC1, XF_NPPC8 ");
       assert(((_src.rows <= ROWS) && (_src.cols <= COLS)) && "ROWS and COLS should be greater than input image");
   #endif
   // clang-format off
   #pragma HLS INLINE OFF
       // clang-format on
   
       uint32_t hist_array[XF_CHANNELS(SRC_T, NPC)][256] = {0};
       uint16_t width = _src.cols >> (XF_BITSHIFT(NPC));
       uint16_t height = _src.rows;
   
       xFHistogramKernel<SRC_T, ROWS, COLS, XF_DEPTH(SRC_T, NPC), NPC, XF_WORDWIDTH(SRC_T, NPC),
                         ((COLS >> (XF_BITSHIFT(NPC))) >> 1), XF_CHANNELS(SRC_T, NPC)>(_src, hist_array, height, width);
   
       for (int i = 0; i < (XF_CHANNELS(SRC_T, NPC)); i++) {
           for (int j = 0; j < 256; j++) {
   // clang-format off
   #pragma HLS LOOP_TRIPCOUNT min=1 max=256
   #pragma HLS PIPELINE
   #pragma HLS LOOP_FLATTEN off
               // clang-format on
               histogram[(i * 256) + j] = hist_array[i][j];
           }
       }
   }
   
   } // namespace cv
   } // namespace xf
   #endif // _XF_HISTOGRAM_HPP_