Files
2026-07-13 13:17:40 +08:00

94 lines
2.5 KiB
Python

#!/usr/bin/env python3
import os
import PIL
import streaming
import ray
def preprocess_mosaic(input_dir, output_dir):
print("Writing to mosaic...")
ds = ray.data.read_images(input_dir, mode="RGB")
it = ds.iter_rows()
columns = {"image": "pil", "label": "int"}
# If reading from local disk, should turn off compression and use
# streaming.LocalDataset.
# If uploading to S3, turn on compression (e.g., compression="snappy") and
# streaming.StreamingDataset.
with streaming.MDSWriter(out=output_dir, columns=columns, compression=None) as out:
for i, img in enumerate(it):
img = PIL.Image.fromarray(img["image"])
out.write(
{
"image": img,
"label": 0,
}
)
if i % 10 == 0:
print(f"Wrote {i} images.")
def preprocess_parquet(input_dir, output_dir, target_partition_size=None):
print("Writing to parquet...")
def to_bytes(row):
row["height"] = row["image"].shape[0]
row["width"] = row["image"].shape[1]
row["image"] = row["image"].tobytes()
return row
if target_partition_size is not None:
ctx = ray.data.context.DataContext.get_current()
ctx.target_max_block_size = target_partition_size
ds = ray.data.read_images(input_dir, mode="RGB")
ds = ds.map(to_bytes)
ds.write_parquet(output_dir)
if __name__ == "__main__":
import argparse
parser = argparse.ArgumentParser(description="Preprocess images.") # noqa: E501
parser.add_argument(
"--data-root",
default="/tmp/imagenet-1gb-data",
type=str,
help="Raw images directory.",
)
parser.add_argument(
"--mosaic-data-root",
default=None,
type=str,
help="Output directory path for mosaic.",
)
parser.add_argument(
"--parquet-data-root",
default=None,
type=str,
help="Output directory path for parquet.",
)
parser.add_argument(
"--max-mb-per-file",
default=64,
type=int,
)
args = parser.parse_args()
ray.init()
if args.mosaic_data_root is not None:
os.makedirs(args.mosaic_data_root)
preprocess_mosaic(args.data_root, args.mosaic_data_root)
if args.parquet_data_root is not None:
os.makedirs(args.parquet_data_root)
preprocess_parquet(
args.data_root,
args.parquet_data_root,
target_partition_size=args.max_mb_per_file * 1024 * 1024,
)