mindspore.dataset.STL10Dataset

class mindspore.dataset.STL10Dataset(dataset_dir, usage=None, num_samples=None, num_parallel_workers=None, shuffle=None, sampler=None, num_shards=None, shard_id=None, cache=None)[source]

STL-10 dataset.

The generated dataset has two columns: [image, label] . The tensor of column image is of the uint8 type. The tensor of column label is of a scalar of int32 type.

Parameters
  • dataset_dir (str) – Path to the root directory that contains the dataset.

  • usage (str, optional) – Usage of this dataset, can be 'train', 'test', 'unlabeled', 'train+unlabeled' or 'all' . 'train' will read from 5,000 train samples, 'test' will read from 8,000 test samples, 'unlabeled' will read from all 100,000 samples, and 'train+unlabeled' will read from 105000 samples, 'all' will read all the samples Default: None , all samples.

  • num_samples (int, optional) – The number of images to be included in the dataset. Default: None , all images.

  • num_parallel_workers (int, optional) – Number of worker threads to read the data. Default: None , will use global default workers(8), it can be set by mindspore.dataset.config.set_num_parallel_workers() .

  • shuffle (bool, optional) – Whether to perform shuffle on the dataset. Default: None , expected order behavior shown in the table below.

  • sampler (Sampler, optional) – Object used to choose samples from the dataset. Default: None , expected order behavior shown in the table below.

  • num_shards (int, optional) – Number of shards that the dataset will be divided into. Default: None . When this argument is specified, num_samples reflects the max sample number of per shard.

  • shard_id (int, optional) – The shard ID within num_shards . Default: None . This argument can only be specified when num_shards is also specified.

  • cache (DatasetCache, optional) – Use tensor caching service to speed up dataset processing. More details: Single-Node Data Cache . Default: None , which means no cache is used.

Raises
  • RuntimeError – If dataset_dir is not valid or does not exist or does not contain data files.

  • RuntimeError – If sampler and shuffle are specified at the same time.

  • RuntimeError – If sampler and num_shards/shard_id are specified at the same time.

  • RuntimeError – If num_shards is specified but shard_id is None.

  • RuntimeError – If shard_id is specified but num_shards is None.

  • ValueError – If usage is invalid.

  • ValueError – If num_parallel_workers exceeds the max thread numbers.

  • ValueError – If shard_id is not in range of [0, num_shards ).

Tutorial Examples:

Note

  • This dataset can take in a sampler. ‘sampler’ and ‘shuffle’ are mutually exclusive. The table below shows what input arguments are allowed and their expected behavior.

Expected Order Behavior of Using sampler and shuffle

Parameter ‘sampler’

Parameter ‘shuffle’

Expected Order Behavior

None

None

random order

None

True

random order

None

False

sequential order

Sampler object

None

order defined by sampler

Sampler object

True

not allowed

Sampler object

False

not allowed

Examples

>>> import mindspore.dataset as ds
>>> stl10_dataset_dir = "/path/to/stl10_dataset_directory"
>>>
>>> # 1) Get all samples from STL10 dataset in sequence
>>> dataset = ds.STL10Dataset(dataset_dir=stl10_dataset_dir, shuffle=False)
>>>
>>> # 2) Randomly select 350 samples from STL10 dataset
>>> dataset = ds.STL10Dataset(dataset_dir=stl10_dataset_dir, num_samples=350, shuffle=True)
>>>
>>> # 3) Get samples from STL10 dataset for shard 0 in a 2-way distributed training
>>> dataset = ds.STL10Dataset(dataset_dir=stl10_dataset_dir, num_shards=2, shard_id=0)

About STL10 dataset:

STL10 dataset consists of 10 classes: airplane, bird, car, cat, deer, dog, horse, monkey, ship, truck. Images are 96x96 pixels, color. 500 training images, 800 test images per class and 100000 unlabeled images. Labels are 0-indexed, and unlabeled images have -1 as their labels.

Here is the original STL10 dataset structure. You can unzip the dataset files into this directory structure and read by MindSpore’s API.

.
└── stl10_dataset_dir
     ├── train_X.bin
     ├── train_y.bin
     ├── test_X.bin
     ├── test_y.bin
     └── unlabeled_X.bin

Citation of STL10 dataset:

@techreport{Coates10,
author       = {Adam Coates},
title        = {Learning multiple layers of features from tiny images},
year         = {20010},
howpublished = {https://cs.stanford.edu/~acoates/stl10/},
description  = {The STL-10 dataset consists of 96x96 RGB images in 10 classes,
                with 500 training images and 800 testing images per class.
                There are 5000 training images and 8000 test images.
                It also has 100000 unlabeled images for unsupervised learning.
                These examples are extracted from a similar but broader distribution of images.
                }
}

Pre-processing Operation

mindspore.dataset.Dataset.apply

Apply a function in this dataset.

mindspore.dataset.Dataset.concat

Concatenate the dataset objects in the input list.

mindspore.dataset.Dataset.filter

Filter dataset by prediction.

mindspore.dataset.Dataset.flat_map

Map func to each row in dataset and flatten the result.

mindspore.dataset.Dataset.map

Apply each operation in operations to this dataset.

mindspore.dataset.Dataset.project

The specified columns will be selected from the dataset and passed into the pipeline with the order specified.

mindspore.dataset.Dataset.rename

Rename the columns in input datasets.

mindspore.dataset.Dataset.repeat

Repeat this dataset count times.

mindspore.dataset.Dataset.reset

Reset the dataset for next epoch.

mindspore.dataset.Dataset.save

Save the dynamic data processed by the dataset pipeline in common dataset format.

mindspore.dataset.Dataset.shuffle

Shuffle the dataset by creating a cache with the size of buffer_size .

mindspore.dataset.Dataset.skip

Skip the first N elements of this dataset.

mindspore.dataset.Dataset.split

Split the dataset into smaller, non-overlapping datasets.

mindspore.dataset.Dataset.take

Takes at most given numbers of elements from the dataset.

mindspore.dataset.Dataset.zip

Zip the datasets in the sense of input tuple of datasets.

Batch

mindspore.dataset.Dataset.batch

Combine batch_size number of consecutive rows into batch which apply per_batch_map to the samples first.

mindspore.dataset.Dataset.bucket_batch_by_length

Bucket elements according to their lengths.

mindspore.dataset.Dataset.padded_batch

Combine batch_size number of consecutive rows into batch which apply pad_info to the samples first.

Iterator

mindspore.dataset.Dataset.create_dict_iterator

Create an iterator over the dataset.

mindspore.dataset.Dataset.create_tuple_iterator

Create an iterator over the dataset.

Attribute

mindspore.dataset.Dataset.get_batch_size

Return the size of batch.

mindspore.dataset.Dataset.get_class_indexing

Return the class index.

mindspore.dataset.Dataset.get_col_names

Return the names of the columns in dataset.

mindspore.dataset.Dataset.get_dataset_size

Return the number of batches in an epoch.

mindspore.dataset.Dataset.get_repeat_count

Get the replication times in RepeatDataset.

mindspore.dataset.Dataset.input_indexs

Get the column index, which represents the corresponding relationship between the data column order and the network when using the sink mode.

mindspore.dataset.Dataset.num_classes

Get the number of classes in a dataset.

mindspore.dataset.Dataset.output_shapes

Get the shapes of output data.

mindspore.dataset.Dataset.output_types

Get the types of output data.

Apply Sampler

mindspore.dataset.MappableDataset.add_sampler

Add a child sampler for the current dataset.

mindspore.dataset.MappableDataset.use_sampler

Replace the last child sampler of the current dataset, remaining the parent sampler unchanged.

Others

mindspore.dataset.Dataset.device_que

Return a transferred Dataset that transfers data through a device.

mindspore.dataset.Dataset.sync_update

Release a blocking condition and trigger callback with given data.

mindspore.dataset.Dataset.sync_wait

Add a blocking condition to the input Dataset and a synchronize action will be applied.

mindspore.dataset.Dataset.to_json

Serialize a pipeline into JSON string and dump into file if filename is provided.