Spaces:
Sleeping
Sleeping
File size: 3,475 Bytes
6db48b4 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 |
"""图片压缩工具"""
import io
from PIL import Image
from typing import Optional
def compress_image(
image_data: bytes,
max_size_kb: int = 200, # 默认200KB
quality_start: int = 85,
quality_min: int = 20,
max_dimension: int = 2048
) -> bytes:
"""
压缩图片到指定大小以内
Args:
image_data: 原始图片数据
max_size_kb: 最大文件大小（KB）
quality_start: 起始压缩质量（1-100）
quality_min: 最低压缩质量（1-100）
max_dimension: 最大边长（像素）
Returns:
压缩后的图片数据
"""
max_size_bytes = max_size_kb * 1024
# 如果原图已经小于目标大小，直接返回
if len(image_data) <= max_size_bytes:
return image_data
try:
# 打开图片
img = Image.open(io.BytesIO(image_data))
# 转换为 RGB（处理 RGBA 等格式）
if img.mode in ('RGBA', 'LA', 'P'):
background = Image.new('RGB', img.size, (255, 255, 255))
if img.mode == 'P':
img = img.convert('RGBA')
background.paste(img, mask=img.split()[-1] if img.mode in ('RGBA', 'LA') else None)
img = background
elif img.mode != 'RGB':
img = img.convert('RGB')
# 如果图片尺寸过大，先缩小
width, height = img.size
if width > max_dimension or height > max_dimension:
ratio = min(max_dimension / width, max_dimension / height)
new_width = int(width * ratio)
new_height = int(height * ratio)
img = img.resize((new_width, new_height), Image.Resampling.LANCZOS)
# 逐步降低质量直到满足大小要求
quality = quality_start
compressed_data = None
while quality >= quality_min:
output = io.BytesIO()
img.save(output, format='JPEG', quality=quality, optimize=True)
compressed_data = output.getvalue()
if len(compressed_data) <= max_size_bytes:
break
quality -= 5
# 如果还是太大，进一步缩小尺寸
if len(compressed_data) > max_size_bytes:
width, height = img.size
while len(compressed_data) > max_size_bytes and max(width, height) > 512:
width = int(width * 0.9)
height = int(height * 0.9)
img_resized = img.resize((width, height), Image.Resampling.LANCZOS)
output = io.BytesIO()
img_resized.save(output, format='JPEG', quality=quality_min, optimize=True)
compressed_data = output.getvalue()
original_size_kb = len(image_data) / 1024
compressed_size_kb = len(compressed_data) / 1024
compression_ratio = (1 - compressed_size_kb / original_size_kb) * 100
print(f"[图片压缩] {original_size_kb:.1f}KB → {compressed_size_kb:.1f}KB (压缩 {compression_ratio:.1f}%)")
return compressed_data
except Exception as e:
print(f"[图片压缩] 压缩失败，返回原图: {e}")
return image_data
def compress_images(images: list[bytes], max_size_kb: int = 200) -> list[bytes]:
"""
批量压缩图片
Args:
images: 图片数据列表
max_size_kb: 最大文件大小（KB）
Returns:
压缩后的图片数据列表
"""
return [compress_image(img, max_size_kb) for img in images]
|