mnist-text-default / mnist-text-default.py
Fraser Greenlee
test change
4d04230
"""MNIST text dataset."""
from __future__ import absolute_import, division, print_function
import json
import os
import math
import numpy as np
import datasets
_DESCRIPTION = """\
MNIST dataset adapted to a text-based representation.
This allows testing interpolation quality for Transformer-VAEs.
System is heavily inspired by Matthew Rayfield's work https://youtu.be/Z9K3cwSL6uM
Works by quantising each MNIST pixel into one of 64 characters.
Every sample has an up & down version to encourage the model to learn rotation invarient features.
Use `.array_to_text(` and `.text_to_array(` methods to test your generated data.
Data format:
- text: (30 x 28 tokens, 840 tokens total): Textual representation of MNIST digit, for example:
```
00 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
01 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
02 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
03 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
04 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
05 down ! ! ! ! ! ! ! ! ! ! ! ! ! % % % @ C L ' J a ^ @ ! ! ! !
06 down ! ! ! ! ! ! ! ! ( * 8 G K ` ` ` ` ` Y L ` ] Q 1 ! ! ! !
07 down ! ! ! ! ! ! ! - \ ` ` ` ` ` ` ` ` _ 8 5 5 / * ! ! ! ! !
08 down ! ! ! ! ! ! ! % W ` ` ` ` ` R N ^ ] ! ! ! ! ! ! ! ! ! !
09 down ! ! ! ! ! ! ! ! 5 H ; ` ` T # ! + G ! ! ! ! ! ! ! ! ! !
10 down ! ! ! ! ! ! ! ! ! $ ! G ` 7 ! ! ! ! ! ! ! ! ! ! ! ! ! !
11 down ! ! ! ! ! ! ! ! ! ! ! C ` P ! ! ! ! ! ! ! ! ! ! ! ! ! !
12 down ! ! ! ! ! ! ! ! ! ! ! # P ` 2 ! ! ! ! ! ! ! ! ! ! ! ! !
13 down ! ! ! ! ! ! ! ! ! ! ! ! ) ] Y I < ! ! ! ! ! ! ! ! ! ! !
14 down ! ! ! ! ! ! ! ! ! ! ! ! ! 5 ] ` ` > ' ! ! ! ! ! ! ! ! !
15 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! , O ` ` F ' ! ! ! ! ! ! ! !
16 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! % 8 ` ` O ! ! ! ! ! ! ! !
17 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! _ ` _ 1 ! ! ! ! ! ! !
18 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! , A N ` ` T ! ! ! ! ! ! ! !
19 down ! ! ! ! ! ! ! ! ! ! ! ! * F Z ` ` ` _ N ! ! ! ! ! ! ! !
20 down ! ! ! ! ! ! ! ! ! ! ' = X ` ` ` ` S 4 ! ! ! ! ! ! ! ! !
21 down ! ! ! ! ! ! ! ! & 1 V ` ` ` ` R 5 ! ! ! ! ! ! ! ! ! ! !
22 down ! ! ! ! ! ! % K W ` ` ` ` Q 5 # ! ! ! ! ! ! ! ! ! ! ! !
23 down ! ! ! ! . L Y ` ` ` ` ^ B # ! ! ! ! ! ! ! ! ! ! ! ! ! !
24 down ! ! ! ! C ` ` ` V B B % ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
25 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
26 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
27 down ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
```
- label: Just a number with the texts matching label.
"""
_CITATION = """\
@dataset{dataset,
author = {Fraser Greenlee},
year = {2021},
month = {1},
pages = {},
title = {MNIST text dataset.},
doi = {}
}
"""
_TRAIN_DOWNLOAD_URL = "https://raw.githubusercontent.com/Fraser-Greenlee/my-huggingface-datasets/master/data/mnist-text/train.json.zip"
_TEST_DOWNLOAD_URL = "https://raw.githubusercontent.com/Fraser-Greenlee/my-huggingface-datasets/master/data/mnist-text/test.json"
LABELS = list(range(10))
CUSTOM_METHODS = ['array_to_text', 'text_to_array']
IMG_SIZE = (30, 28)
class MnistText(datasets.GeneratorBasedBuilder):
"""MNIST represented by text."""
def as_dataset(self, *args, **kwargs):
f"""
Return a Dataset for the specified split.
Modified to add custom methods {CUSTOM_METHODS} to the dataset.
This allows rendering the text as images & vice versa.
"""
a_dataset = super().as_dataset(*args, **kwargs)
for method in CUSTOM_METHODS:
setattr(a_dataset, f'custom_{method}', getattr(self, method))
return a_dataset
@staticmethod
def array_to_text(pixels: np.array):
'''
Takes a 2D array of pixel brightnesses and converts them to text.
Uses 64 tokens to represent all brightness values.
'''
width = pixels.shape[0]
height = pixels.shape[1]
lines = []
for y in range(height):
split = ['%02d down' % y]
for x in range(width):
brightness = pixels[y, x]
mBrightness = math.floor(brightness * 64)
s = chr(mBrightness + 33)
split.append(s)
lines.append(' '.join(split))
reversed = []
for line in lines:
reversed.insert(0, (line.replace(' down ', ' up ', 1)))
return ['\n'.join(lines), '\n'.join(reversed)]
@staticmethod
def text_to_array(text: str):
'''
Takes a text sequences and tries to convert it into a 2D numpy array of brightnesses.
If parts of the text don't match the format they will be skipped.
'''
lines = text.strip().split('\n')
pixels = np.zeros((IMG_SIZE[1], IMG_SIZE[0] - 2))
tokens = None
for y in range(min(IMG_SIZE[1], len(lines))):
line = lines[y].strip()
tokens = line.split(' ')
for i in range(2, min(IMG_SIZE[0], len(tokens))):
token = tokens[i]
if len(token) == 1:
tkn_v = (ord(token) - 33)
if tkn_v >= 0 and tkn_v <= 64:
pixels[y, i - 2] = tkn_v / 64
if not lines:
return pixels
if tokens and len(tokens) > 1 and tokens[1] == 'up':
pixels = pixels[::-1]
return pixels
def _info(self):
return datasets.DatasetInfo(
description=_DESCRIPTION,
features=datasets.Features(
{
'label': datasets.features.ClassLabel(names=LABELS),
'text': datasets.Value("string"),
}
),
homepage="https://github.com/Fraser-Greenlee/my-huggingface-datasets",
citation=_CITATION,
)
def _split_generators(self, dl_manager):
train_path = dl_manager.download_and_extract(_TRAIN_DOWNLOAD_URL)
test_path = dl_manager.download_and_extract(_TEST_DOWNLOAD_URL)
return [
datasets.SplitGenerator(
name=datasets.Split.TRAIN, gen_kwargs={"filepath": os.path.join(train_path, 'train.json')}
),
datasets.SplitGenerator(name=datasets.Split.TEST, gen_kwargs={"filepath": test_path}),
]
def _generate_examples(self, filepath):
"""Generate examples."""
with open(filepath, encoding="utf-8") as json_lines_file:
data = []
for line in json_lines_file:
data.append(json.loads(line))
for id_, row in enumerate(data):
yield id_, row