vllm/vllm/multimodal/image.py
Harry Mellor 8fcaaf6a16
Update Optional[x] -> x | None and Union[x, y] to x | y (#26633)
Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
2025-10-12 09:51:31 -07:00

131 lines
4.3 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
from io import BytesIO
from pathlib import Path
import pybase64
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
def rgba_to_rgb(
image: Image.Image,
background_color: tuple[int, int, int] | list[int] = (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", **kwargs) -> None:
super().__init__()
self.image_mode = image_mode
# `kwargs` contains custom arguments from
# --media-io-kwargs for this modality.
# They can be passed to the underlying
# media loaders (e.g. custom implementations)
# for flexible control.
self.kwargs = kwargs
# Extract RGBA background color from kwargs if provided
# Default to white background for backward compatibility
rgba_bg = kwargs.get("rgba_background_color", (255, 255, 255))
# Convert list to tuple for consistency
if isinstance(rgba_bg, list):
rgba_bg = tuple(rgba_bg)
# Validate rgba_background_color format
if not (
isinstance(rgba_bg, tuple)
and len(rgba_bg) == 3
and all(isinstance(c, int) and 0 <= c <= 255 for c in rgba_bg)
):
raise ValueError(
"rgba_background_color must be a list or tuple of 3 integers "
"in the range [0, 255]."
)
self.rgba_background_color = rgba_bg
def _convert_image_mode(self, image: Image.Image) -> Image.Image:
"""Convert image mode with custom background color."""
if image.mode == self.image_mode:
return image
elif image.mode == "RGBA" and self.image_mode == "RGB":
return rgba_to_rgb(image, self.rgba_background_color)
else:
return convert_image_mode(image, self.image_mode)
def load_bytes(self, data: bytes) -> Image.Image:
image = Image.open(BytesIO(data))
image.load()
return self._convert_image_mode(image)
def load_base64(self, media_type: str, data: str) -> Image.Image:
return self.load_bytes(pybase64.b64decode(data, validate=True))
def load_file(self, filepath: Path) -> Image.Image:
image = Image.open(filepath)
image.load()
return self._convert_image_mode(image)
def encode_base64(
self,
media: Image.Image,
*,
image_format: str = "JPEG",
) -> str:
image = media
with BytesIO() as buffer:
image = self._convert_image_mode(image)
image.save(buffer, image_format)
data = buffer.getvalue()
return pybase64.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(pybase64.b64decode(data, validate=True))
def load_file(self, filepath: Path) -> torch.Tensor:
return torch.load(filepath, weights_only=True)
def encode_base64(self, media: torch.Tensor) -> str:
return pybase64.b64encode(media.numpy()).decode("utf-8")