vllm/vllm/multimodal/image.py
Chenheli Hua 04eb88dc80
Re-submit: Fix: Proper RGBA -> RGB conversion for PIL images. (#18569)
Signed-off-by: Chenheli Hua <huachenheli@outlook.com>
2025-05-23 01:59:18 +00:00

97 lines
2.9 KiB
Python

# SPDX-License-Identifier: Apache-2.0
import base64
from io import BytesIO
from pathlib import Path
import torch
from PIL import Image
from .base import MediaIO
def rescale_image_size(image: Image.Image,
size_factor: float,
transpose: int = -1) -> Image.Image:
"""Rescale the dimensions of an image by a constant factor."""
new_width = int(image.width * size_factor)
new_height = int(image.height * size_factor)
image = image.resize((new_width, new_height))
if transpose >= 0:
image = image.transpose(Image.Transpose(transpose))
return image
# TODO: Support customizable background color to fill in.
def rgba_to_rgb(
image: Image.Image, background_color=(255, 255, 255)) -> Image.Image:
"""Convert an RGBA image to RGB with filled background color."""
assert image.mode == "RGBA"
converted = Image.new("RGB", image.size, background_color)
converted.paste(image, mask=image.split()[3]) # 3 is the alpha channel
return converted
def convert_image_mode(image: Image.Image, to_mode: str):
if image.mode == to_mode:
return image
elif image.mode == "RGBA" and to_mode == "RGB":
return rgba_to_rgb(image)
else:
return image.convert(to_mode)
class ImageMediaIO(MediaIO[Image.Image]):
def __init__(self, *, image_mode: str = "RGB") -> None:
super().__init__()
self.image_mode = image_mode
def load_bytes(self, data: bytes) -> Image.Image:
image = Image.open(BytesIO(data))
image.load()
return convert_image_mode(image, self.image_mode)
def load_base64(self, media_type: str, data: str) -> Image.Image:
return self.load_bytes(base64.b64decode(data))
def load_file(self, filepath: Path) -> Image.Image:
image = Image.open(filepath)
image.load()
return convert_image_mode(image, self.image_mode)
def encode_base64(
self,
media: Image.Image,
*,
image_format: str = "JPEG",
) -> str:
image = media
with BytesIO() as buffer:
image = convert_image_mode(image, self.image_mode)
image.save(buffer, image_format)
data = buffer.getvalue()
return base64.b64encode(data).decode('utf-8')
class ImageEmbeddingMediaIO(MediaIO[torch.Tensor]):
def __init__(self) -> None:
super().__init__()
def load_bytes(self, data: bytes) -> torch.Tensor:
buffer = BytesIO(data)
return torch.load(buffer, weights_only=True)
def load_base64(self, media_type: str, data: str) -> torch.Tensor:
return self.load_bytes(base64.b64decode(data))
def load_file(self, filepath: Path) -> torch.Tensor:
return torch.load(filepath, weights_only=True)
def encode_base64(self, media: torch.Tensor) -> str:
return base64.b64encode(media.numpy()).decode('utf-8')