| // |
| // Copyright © 2020 Arm Ltd and Contributors. All rights reserved. |
| // SPDX-License-Identifier: MIT |
| // |
| |
| #include "SSDResultDecoder.hpp" |
| |
| #include <cassert> |
| #include <algorithm> |
| #include <cmath> |
| #include <stdexcept> |
| namespace od |
| { |
| |
| DetectedObjects SSDResultDecoder::Decode(const common::InferenceResults<float>& networkResults, |
| const common::Size& outputFrameSize, |
| const common::Size& resizedFrameSize, |
| const std::vector<std::string>& labels) |
| { |
| // SSD network outputs 4 tensors: bounding boxes, labels, probabilities, number of detections. |
| if (networkResults.size() != 4) |
| { |
| throw std::runtime_error("Number of outputs from SSD model doesn't equal 4"); |
| } |
| |
| DetectedObjects detectedObjects; |
| const int numDetections = static_cast<int>(std::lround(networkResults[3][0])); |
| |
| double longEdgeInput = std::max(resizedFrameSize.m_Width, resizedFrameSize.m_Height); |
| double longEdgeOutput = std::max(outputFrameSize.m_Width, outputFrameSize.m_Height); |
| const double resizeFactor = longEdgeOutput/longEdgeInput; |
| |
| for (int i=0; i<numDetections; ++i) |
| { |
| if (networkResults[2][i] > m_objectThreshold) |
| { |
| DetectedObject detectedObject; |
| detectedObject.SetScore(networkResults[2][i]); |
| auto classId = std::lround(networkResults[1][i]); |
| |
| if (classId < labels.size()) |
| { |
| detectedObject.SetLabel(labels[classId]); |
| } |
| else |
| { |
| detectedObject.SetLabel(std::to_string(classId)); |
| } |
| detectedObject.SetId(classId); |
| |
| // Convert SSD bbox outputs (ratios of image size) to pixel values. |
| double topLeftY = networkResults[0][i*4 + 0] * resizedFrameSize.m_Height; |
| double topLeftX = networkResults[0][i*4 + 1] * resizedFrameSize.m_Width; |
| double botRightY = networkResults[0][i*4 + 2] * resizedFrameSize.m_Height; |
| double botRightX = networkResults[0][i*4 + 3] * resizedFrameSize.m_Width; |
| |
| // Scale the coordinates to output frame size. |
| topLeftY *= resizeFactor; |
| topLeftX *= resizeFactor; |
| botRightY *= resizeFactor; |
| botRightX *= resizeFactor; |
| |
| assert(botRightX > topLeftX); |
| assert(botRightY > topLeftY); |
| |
| // Internal BoundingBox stores box top left x,y and width, height. |
| detectedObject.SetBoundingBox({static_cast<int>(std::round(topLeftX)), |
| static_cast<int>(std::round(topLeftY)), |
| static_cast<unsigned int>(botRightX - topLeftX), |
| static_cast<unsigned int>(botRightY - topLeftY)}); |
| |
| detectedObjects.emplace_back(detectedObject); |
| } |
| } |
| return detectedObjects; |
| } |
| |
| SSDResultDecoder::SSDResultDecoder(float ObjectThreshold) : m_objectThreshold(ObjectThreshold) {} |
| |
| }// namespace od |