A Super Resolution Dataset of Digital Rocks (DRSRD1): Sandstone and Carbonate

Digital Rocks Super Resolution Dataset 1: Sandstone and Carbonate micro-CT Images used for 2D and 3D Super Resolution Machine Learning Training, Validation, and Testing.

This dataset comprises of organised 2D slices and 3D volumes of Bentheimer Sandstone [sourced internally from UNSW] and Estaillades Carbonate [https://www.digitalrocksportal.org/projects/58/origin_data/209/], imaged at a resolution of 3.8 and 3.1 microns respectively.

The dataset is organised in a similar fashion to the DIV2K dataset : (https://data.vision.ee.ethz.ch/cvl/DIV2K/). To the knowledge of the authors, this dataset is the first of its kind to be used for the purpose of benchmarking Super Resolution algorithms in digital rock images. This dataset has been used thus far to test several Super Resolution Convolutional Neural Networks (SRCNN). Results are described in the Related Publications tab on this page.

Wang, Y., Armstrong, R.T., & Mostaghimi, P. (2019). Super Resolution Convolutional Neural Network Models for Enhancing
Resolution of Rock Micro-CT Images. arXiv:1904.07470 ( https://arxiv.org/pdf/1904.07470.pdf )

Please cite both this dataset (use its DOI) as well as the related journal publication.

Data overview:
The dataset is divided into:
- 2D and 3D folders
- Sandstone and Carbonate Datasets
- Combined shuffled Datasets
- High Resolution, 2x and 4x downsampled datasets using the Matlab imresize and imresize3 functions with default settings and randomised settings
- 2D HR images measure 800x800, cropped samples from the centre of the original cylindrical images, saved as PNG files
- 3D HR images measure 80x80x80, cropped from the centre of the original cylindrical images, saved as octave and scipy readable MAT files
- 800 images are available for training, 100 for validation, and 100 for testing.
- Shuffled subsets contain 1600 images for training, 200 for validation, and 200 for testing

The folder structure is as follows:
- DRSRD1/ - the parent folder
- DRSRD1/DRSRD1_2D/ - folder for all 2D data
- DRSRD1/DRSRD1_2D/sandstone2D - folder for 2D sandstone Data
- DRSRD1/DRSRD1_2D/carbonate2D- folder for 2D carbonate Data
- DRSRD1/DRSRD1_2D/shuffled2D - folder for 2D shuffled Data
and similarly for the 3D dataset, found in ./DRSRD1/DRSRD1_3D/ under the exact same structure.
Within each carbonate, sandstone, and shuffled folder, the structure is as follows, using the 2D shuffled folder as example:
- /shuffled2D_train_HR/ - 0001.png, 0002.png, ..., 0800.png train HR images
- /shuffled2D_train_LR_default_X2/ -- 0001x2.png, 0002x2.png, ..., 0800x2.png train LR images, downscale factor x2
- /shuffled2D_train_LR_default_X4/ -- 0001x4.png, 0002x4.png, ..., 0800x4.png train LR images, downscale factor x4
- /shuffled2D_train_LR_unknown_X2/ -- 0001x2.png, 0002x2.png, ..., 0800x2.png train LR images, downscale factor x2
- /shuffled2D_train_LR_unknown_X4/ -- 0001x4.png, 0002x4.png, ..., 0800x4.png train LR images, downscale factor x4
- Validation
- /shuffled2D_valid_HR/ -- 0801.png, 0802.png, ..., 0900.png validation HR images
- /shuffled2D_valid_LR_default_X2/ -- 0801x2.png, 0802x2.png, ..., 0900x2.png train LR images, downscale factor x2
- /shuffled2D_valid_LR_default_X4/ -- 0801x4.png, 0802x4.png, ..., 0900x4.png train LR images, downscale factor x4
- /shuffled2D_valid_LR_unknown_X2/ -- 0801x2.png, 0802x2.png, ..., 0900x2.png train LR images, downscale factor x2
- /shuffled2D_valid_LR_unknown_X4/ -- 0801x4.png, 0802x4.png, ..., 0900x4.png train LR images, downscale factor x4
- Testing
- /shuffled2D_test_HR/ -- 0901.png, 0902.png, ..., 1000.png test HR images
- shuffled2D_test_LR_default_X2/ -- 0901x2.png, 0902x2.png, ..., 1000x2.png train LR images, downscale factor x2
- shuffled2D_test_LR_default_X4/ -- 0901x4.png, 0902x4.png, ..., 1000x4.png train LR images, downscale factor x4
- shuffled2D_test_LR_unknown_X2/ -- 0901x2.png, 0902x2.png, ..., 1000x2.png train LR images, downscale factor x2
- shuffled2D_test_LR_unknown_X4/ -- 0901x4.png, 0902x4.png, ..., 1000x4.png train LR images, downscale factor x4

数字岩石超分辨率数据集1：用于2D与3D超分辨率机器学习训练、验证与测试的砂岩和碳酸盐岩显微CT（micro-CT）图像

本数据集包含整理好的2D切片与3D体数据，分别来自新南威尔士大学（UNSW）内部获取的本特海姆砂岩（Bentheimer Sandstone），以及从数字岩石门户获取的埃斯塔亚德碳酸盐岩（Estaillades Carbonate，来源链接：https://www.digitalrocksportal.org/projects/58/origin_data/209/），二者的成像分辨率分别为3.8微米与3.1微米。

本数据集的组织形式与DIV2K数据集（https://data.vision.ee.ethz.ch/cvl/DIV2K/）类似。据作者所知，本数据集是首个用于数字岩石图像超分辨率算法基准测试的同类数据集。截至目前，本数据集已被用于测试多款超分辨率卷积神经网络（Super Resolution Convolutional Neural Network, SRCNN），相关研究成果详见本页面的“相关出版物”标签页。

Wang Y, Armstrong R T, Mostaghimi P. 2019. 用于提升岩石显微CT图像分辨率的超分辨率卷积神经网络模型[EB/OL]. arXiv:1904.07470. https://arxiv.org/pdf/1904.07470.pdf

请同时引用本数据集（需使用其DOI）以及相关期刊论文。

## 数据集概览
本数据集可划分为以下类别：
- 2D与3D数据文件夹
- 砂岩数据集与碳酸盐岩数据集
- 合并打乱后的数据集
- 高分辨率（High Resolution, HR）以及通过MATLAB的`imresize`与`imresize3`函数，分别以默认参数和随机参数进行2倍、4倍下采样得到的低分辨率（Low Resolution, LR）数据集
- 2D高分辨率图像尺寸为800×800，从原始圆柱形图像中心裁剪得到，以PNG格式存储
- 3D高分辨率图像尺寸为80×80×80，从原始圆柱形图像中心裁剪得到，以可被GNU Octave与SciPy读取的MAT格式存储
- 基础拆分数据集包含800张训练图像、100张验证图像与100张测试图像
- 打乱后的子集则包含1600张训练图像、200张验证图像与200张测试图像

## 文件夹结构
本数据集的目录结构如下：
- `DRSRD1/`：父文件夹
- `DRSRD1/DRSRD1_2D/`：所有2D数据存储文件夹
- `DRSRD1/DRSRD1_2D/sandstone2D`：2D砂岩数据存储文件夹
- `DRSRD1/DRSRD1_2D/carbonate2D`：2D碳酸盐岩数据存储文件夹
- `DRSRD1/DRSRD1_2D/shuffled2D`：2D打乱数据存储文件夹

3D数据集采用完全一致的目录结构，存储于`./DRSRD1/DRSRD1_3D/`路径下。

以下以2D打乱数据文件夹为例，展示砂岩、碳酸盐岩以及打乱数据文件夹的通用内部结构：
- `shuffled2D_train_HR/`：存储训练用高分辨率图像，文件名为0001.png、0002.png……0800.png
- `shuffled2D_train_LR_default_X2/`：存储训练用低分辨率图像（下采样倍率2倍，采用默认参数），文件名为0001x2.png、0002x2.png……0800x2.png
- `shuffled2D_train_LR_default_X4/`：存储训练用低分辨率图像（下采样倍率4倍，采用默认参数），文件名为0001x4.png、0002x4.png……0800x4.png
- `shuffled2D_train_LR_unknown_X2/`：存储训练用低分辨率图像（下采样倍率2倍，采用随机参数），文件名为0001x2.png、0002x2.png……0800x2.png
- `shuffled2D_train_LR_unknown_X4/`：存储训练用低分辨率图像（下采样倍率4倍，采用随机参数），文件名为0001x4.png、0002x4.png……0800x4.png
- **Validation（验证集）**
- `shuffled2D_valid_HR/`：存储验证用高分辨率图像，文件名为0801.png、0802.png……0900.png
- `shuffled2D_valid_LR_default_X2/`：存储验证用低分辨率图像（下采样倍率2倍，默认参数），文件名为0801x2.png、0802x2.png……0900x2.png
- `shuffled2D_valid_LR_default_X4/`：存储验证用低分辨率图像（下采样倍率4倍，默认参数），文件名为0801x4.png、0802x4.png……0900x4.png
- `shuffled2D_valid_LR_unknown_X2/`：存储验证用低分辨率图像（下采样倍率2倍，随机参数），文件名为0801x2.png、0802x2.png……0900x2.png
- `shuffled2D_valid_LR_unknown_X4/`：存储验证用低分辨率图像（下采样倍率4倍，随机参数），文件名为0801x4.png、0802x4.png……0900x4.png
- **Testing（测试集）**
- `shuffled2D_test_HR/`：存储测试用高分辨率图像，文件名为0901.png、0902.png……1000.png
- `shuffled2D_test_LR_default_X2/`：存储测试用低分辨率图像（下采样倍率2倍，默认参数），文件名为0901x2.png、0902x2.png……1000x2.png
- `shuffled2D_test_LR_default_X4/`：存储测试用低分辨率图像（下采样倍率4倍，默认参数），文件名为0901x4.png、0902x4.png……1000x4.png
- `shuffled2D_test_LR_unknown_X2/`：存储测试用低分辨率图像（下采样倍率2倍，随机参数），文件名为0901x2.png、0902x2.png……1000x2.png
- `shuffled2D_test_LR_unknown_X4/`：存储测试用低分辨率图像（下采样倍率4倍，随机参数），文件名为0901x4.png、0902x4.png……1000x4.png