rk1126, 实现 yolov8 目标检测

基于 RKNN 1126 实现 yolov8 目标检测

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Ⓜ️ RKNN 模型转换

1. ONNX

   yolo export model=./weights/yolov8s.pt format=onnx
   

2. 导出 RKNN

   这里选择输出 concat 输入两个节点 onnx::Concat_425 和 onnx::Concat_426

	from rknn.api import RKNN
	 
	ONNX_MODEL = './weights/yolov8s.onnx'
	RKNN_MODEL = './weights/yolov8s.rknn'
	QUA_DATASETS = './data/coco/datasets.txt'
	QUA_DATASETS_analysis = './data/coco/images/datasets_ans.txt'
	 
	QUANTIZE_ON = True
	 
	if __name__ == '__main__':
	    # Create RKNN object
	    rknn = RKNN(verbose=True)
	    # pre-process config  
	    # asymmetric_affine-u8, dynamic_fixed_point-i8, dynamic_fixed_point-i16
	    print('--> config model')
	    rknn.config(
	            reorder_channel='0 1 2',
	            mean_values=[[0, 0, 0]],
	            std_values=[[255, 255, 255]],
	            quantized_algorithm="normal",
	            optimization_level=3,
	            target_platform = 'rk1126',
	            quantize_input_node= QUANTIZE_ON,
	            quantized_dtype='asymmetric_quantized-u8',
	            batch_size = 64,
	            force_builtin_perm = False
	            )
	    print('done')
	 
	    print('--> Loading model')
	    ret = rknn.load_onnx(model=ONNX_MODEL, outputs=['onnx::Concat_425', 'onnx::Concat_426'])
	    if ret != 0:
	        print('Load model  failed!')
	        exit(ret)
	    print('done')
	 
	    # Build model
	    print('--> Building model')
	    ret = rknn.build(do_quantization=QUANTIZE_ON, dataset=QUA_DATASETS,pre_compile=True)  # ,pre_compile=True
	    if ret != 0:
	        print('Build occ_model failed!')
	        exit(ret)
	    print('done')
	 
	    # Export rknn model
	    print('--> Export RKNN model')
	    ret = rknn.export_rknn(RKNN_MODEL)
	    if ret != 0:
	        print('Export occ_model failed!')
	        exit(ret)
	    print('done')

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​ RKNN板子上推理

1. 前处理，为了简单方便直接 resize

   cv::Mat resize_img(INPUT_H, INPUT_W, CV_8UC3);
   cv::resize(src, resize_img, resize_img.size(), 0, 0, cv::INTER_LINEAR);
   cv::Mat pr_img;
   cvtColor(resize_img, pr_img, COLOR_BGR2RGB);
   

2. 模型推理

   /* Init input tensor */
   rknn_input inputs[1];
   memset(inputs, 0, sizeof(inputs));
   inputs[0].index = 0;
   inputs[0].buf = pr_img.data;
   // inputs[0].buf = input_data;
   inputs[0].type = RKNN_TENSOR_UINT8;
   inputs[0].size = input_width * input_height * input_channel;
   inputs[0].fmt = RKNN_TENSOR_NHWC;
   inputs[0].pass_through = 0;
   
   // printf("img.cols: %d, img.rows: %d\n", pr_img.cols, pr_img.rows);
   printf("input io_num: %d, output io_num: %d\n", io_num.n_input, io_num.n_output);
   auto t1 = std::chrono::steady_clock::now();
   rknn_inputs_set(ctx, io_num.n_input, inputs);
   std::cout << "rknn_inputs_set time: " << std::chrono::duration_cast<std::chrono::duration<double>>(std::chrono::steady_clock::now() - t1).count() * 1000 << " ms." << std::endl;
   ret = rknn_run(ctx, NULL);
   std::cout << "rknn_run time: " << std::chrono::duration_cast<std::chrono::duration<double>>(std::chrono::steady_clock::now() - t1).count() * 1000 << " ms." << std::endl;
   if (ret < 0)
   {
   	printf("ctx error ret=%d\n", ret);
   	return -1;
   }
   
   /* Init output tensor */
   rknn_output outputs[io_num.n_output];
   memset(outputs, 0, sizeof(outputs));
   for (int i = 0; i < io_num.n_output; i++)
   {
   	outputs[i].want_float = 1;
   }
   ret = rknn_outputs_get(ctx, io_num.n_output, outputs, NULL);
   if (ret < 0)
   {
   	printf("outputs error ret=%d\n", ret);
   	return -1;
   }
   

3. 后处理

   1. 导出模型没有进行 concat 操作，所以自行处理.

   cv::Mat out_buffer0_mat;
   std::vector<Mat> vImgs;
   cv::Mat out0_mat = cv::Mat(4, Num_box, CV_32F, (float*)outputs[0].buf);
   cv::Mat out1_mat = cv::Mat(CLASSES, Num_box, CV_32F, (float*)outputs[1].buf);
   vImgs.push_back(out0_mat);       // 4 * 8400
   vImgs.push_back(out1_mat);       // CLASSES * 8400
   vconcat(vImgs, out_buffer0_mat); // 垂直方向拼接  (CLASSES + 4) * 8400
   

   2. 后处理

   std::vector<Detection> detections; // 结果id数组
   
   std::vector<int> classIds;      // 结果id数组
   std::vector<float> confidences; // 结果每个id对应置信度数组
   std::vector<cv::Rect> boxes;    // 每个id矩形框
   auto start = std::chrono::system_clock::now();
   for (int i = 0; i < Num_box; i++)
   {
       // 输出是1*net_length*Num_box;所以每个box的属性是每隔Num_box取一个值，共net_length个值
       cv::Mat scores = out_buffer0_mat(Rect(i, 4, 1, CLASSES)).clone();
   
       Point classIdPoint;
       Point minclassIdPoint;
       double max_class_socre;
       double min_class_socre;
       minMaxLoc(scores, &min_class_socre, &max_class_socre, &minclassIdPoint, &classIdPoint);
   
       // if (max_class_socre > CONF_THRESHOLD)
       //     std::cout << "max_class_socre:" << max_class_socre << std::endl;
   
       max_class_socre = (float)max_class_socre;
       if (max_class_socre >= CONF_THRESHOLD)
       {
           float x = (out_buffer0_mat.at<float>(0, i)) * ratio_w; // cx
           float y = (out_buffer0_mat.at<float>(1, i)) * ratio_h; // cy
           float w = out_buffer0_mat.at<float>(2, i) * ratio_w;   // w
           float h = out_buffer0_mat.at<float>(3, i) * ratio_h;   // h
   
           int left = MAX((x - 0.5 * w), 0);
           int top = MAX((y - 0.5 * h), 0);
           int width = (int)w;
           int height = (int)h;
           if (width <= 0 || height <= 0)
               continue;
           printf("====> id: %d \n", classIdPoint.y);
           classIds.push_back(classIdPoint.y);
           confidences.push_back(max_class_socre);
           boxes.push_back(Rect(left, top, width, height));
       }
   }
   
   // 执行非最大抑制以消除具有较低置信度的冗余重叠框（NMS）![在这里插入图片描述](https://img-blog.csdnimg.cn/direct/a9897fddb01642358b2a9047ccd98067.jpeg#pic_center)
   
   std::vector<int> nms_result;
   cv::dnn::NMSBoxes(boxes, confidences, CONF_THRESHOLD, NMS_THRESHOLD, nms_result);
   
   std::cout << ">>>>> nms_result: " << boxes.size() << " " << nms_result.size() << std::endl;
   
   for (int i = 0; i < nms_result.size(); ++i)
   {
       Detection detection;
       int idx = nms_result[i];
       detection.class_id = classIds[idx];
       detection.conf = confidences[idx];
       detection.box = boxes[idx];
       detections.push_back(detection);
   }
   

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关于遇到的问题 ?

• 当我指定 onnx 最后一层时 (output0)，导出的 rknn模型推理没有结果。个人感觉是 rknn 量化时, concat操作有问题. 所以我改成输出上两个节点，自行拼接. 如果有明白的大佬，望指定一二, 抱拳了 .