【Tensorflow】Tensorflow C++的Tensor和OpenCV的Mat相互转换

这里用tensorflow的C++接口实现tensor和OpenCV Mat的相互转换。其实这里的代码仅仅展示一个个元素怎样映射的，了解原理之后，自己就可以直接写用指针映射，不用for循环一个个元素去赋值了。

void cvMat2tfTensor(cv::Mat input, float inputMean, float inputSTD, tensorflow::Tensor& outputTensor)
	{
		auto outputTensorMapped = outputTensor.tensor();

		input.convertTo(input, CV_32FC3);
		cv::resize(input, input, cv::Size(inputWidth, inputHeight));

		input = input - inputMean;
		input = input / inputSTD;

		int height = input.size().height;
		int width = input.size().width;
		int depth = input.channels();

		const float* data = (float*)input.data;
		for (int y = 0; y < height; ++y)
		{
			const float* dataRow = data + (y * width * depth);
			for (int x = 0; x < width; ++x)
			{
				const float* dataPixel = dataRow + (x * depth);
				for (int c = 0; c < depth; ++c)
				{
					const float* dataValue = dataPixel + c;
					outputTensorMapped(0, y, x, c) = *dataValue;
				}
			}
		}
	}

int tfTensor2cvMat(const tensorflow::Tensor& inputTensor, cv::Mat& output)
	{
		tensorflow::TensorShape inputTensorShape = inputTensor.shape();
		if (inputTensorShape.dims() != 4)
		{
			return -1;
		}

		int height = inputTensorShape.dim_size(1);
		int width = inputTensorShape.dim_size(2);
		int depth = inputTensorShape.dim_size(3);

		output = cv::Mat(height, width, CV_32FC(depth));
		auto inputTensorMapped = inputTensor.tensor();
		float* data = (float*)output.data;
		for (int y = 0; y < height; ++y)
		{
			float* dataRow = data + (y * width * depth);
			for (int x = 0; x < width; ++x)
			{
				float* dataPixel = dataRow + (x * depth);
				for (int c = 0; c < depth; ++c)
				{
					float* dataValue = dataPixel + c;
					*dataValue = inputTensorMapped(0, y, x, c);
				}
			}
		}
		return 0;
	}