Bulk Resize Photos（图片缩放）
The fastest online image resizer.
在线图片优化器
Optimizilla是一款压缩JPEG、GIF和PNG图片至尽可能小尺寸的终极的图像优化器。
StockSnap（图片库4）
The best source for free, CC0, do-what-you-want-with stock photos. Browse and download thousands of copyright-free stock images. No attribution required.
ISO Republic（图片库3和免费视频）
ISO Republic offers over 7,000 of the best high-resolution stock images & videos, all free for personal and commercial use. Download your favorites today.
Free Stock Photos（图片库2）
Browse thousands of beautiful copyright-free images. All our pictures are free to download for personal and commercial use, no attribution required.