位图表情符号

以固定分辨率像素图像渲染的表情符号，以PNG等光栅格式存储在字体文件中。

Bitmap emoji store pre-rendered images at specific pixel dimensions. Common resolutions are 128×128, 96×96, and 64×64 pixels. When scaled beyond their native resolution, they become blurry.

Apple Color Emoji (sbix) and Google Noto Color Emoji (CBDT) both use bitmap approaches. Apple includes multiple resolutions per glyph to handle different display sizes, which is why the font file is over 100MB.

While bitmap emoji reproduce the intended design perfectly at their native size, the industry is gradually moving toward vector formats for better scalability and smaller file sizes.