tinygrad/extra/datasets/imagenet.py

92 lines
3.0 KiB
Python

# for imagenet download prepare.sh and run it
import glob, random, json, math
import numpy as np
from PIL import Image
import functools, pathlib
from tinygrad.helpers import diskcache, getenv
@functools.lru_cache(None)
def get_imagenet_categories():
ci = json.load(open(BASEDIR / "imagenet_class_index.json"))
return {v[0]: int(k) for k,v in ci.items()}
if getenv("MNISTMOCK"):
BASEDIR = pathlib.Path(__file__).parent / "mnist"
@functools.lru_cache(None)
def get_train_files():
if not BASEDIR.exists():
from extra.datasets.fake_imagenet_from_mnist import create_fake_mnist_imagenet
create_fake_mnist_imagenet(BASEDIR)
if not (files:=glob.glob(p:=str(BASEDIR / "train/*/*"))): raise FileNotFoundError(f"No training files in {p}")
return files
else:
BASEDIR = pathlib.Path(__file__).parent / "imagenet"
@diskcache
def get_train_files():
if not (files:=glob.glob(p:=str(BASEDIR / "train/*/*"))): raise FileNotFoundError(f"No training files in {p}")
return files
@functools.lru_cache(None)
def get_val_files():
if not (files:=glob.glob(p:=str(BASEDIR / "val/*/*"))): raise FileNotFoundError(f"No validation files in {p}")
return files
def image_resize(img, size, interpolation):
w, h = img.size
w_new = int((w / h) * size) if w > h else size
h_new = int((h / w) * size) if h > w else size
return img.resize([w_new, h_new], interpolation)
def rand_flip(img):
if random.random() < 0.5:
img = np.flip(img, axis=1).copy()
return img
def center_crop(img):
rescale = min(img.size) / 256
crop_left = (img.width - 224 * rescale) / 2.0
crop_top = (img.height - 224 * rescale) / 2.0
img = img.resize((224, 224), Image.BILINEAR, box=(crop_left, crop_top, crop_left + 224 * rescale, crop_top + 224 * rescale))
return img
# we don't use supplied imagenet bounding boxes, so scale min is just min_object_covered
# https://github.com/tensorflow/tensorflow/blob/e193d8ea7776ef5c6f5d769b6fb9c070213e737a/tensorflow/core/kernels/image/sample_distorted_bounding_box_op.cc
def random_resized_crop(img, size, scale=(0.10, 1.0), ratio=(3/4, 4/3)):
w, h = img.size
area = w * h
# Crop
random_solution_found = False
for _ in range(100):
aspect_ratio = random.uniform(ratio[0], ratio[1])
max_scale = min(min(w * aspect_ratio / h, h / aspect_ratio / w), scale[1])
target_area = area * random.uniform(scale[0], max_scale)
w_new = int(round(math.sqrt(target_area * aspect_ratio)))
h_new = int(round(math.sqrt(target_area / aspect_ratio)))
if 0 < w_new <= w and 0 < h_new <= h:
crop_left = random.randint(0, w - w_new)
crop_top = random.randint(0, h - h_new)
img = img.crop((crop_left, crop_top, crop_left + w_new, crop_top + h_new))
random_solution_found = True
break
if not random_solution_found:
# Center crop
img = center_crop(img)
else:
# Resize
img = img.resize([size, size], Image.BILINEAR)
return img
def preprocess_train(img):
img = random_resized_crop(img, 224)
img = rand_flip(np.array(img))
return img