## 基础

- 像素
- 分辨率（逐行扫描，隔行扫描）
- 位深
- 码率
- stride跨距
- RGB
- YUV(444, 420p, YUVstride对齐)
- 声音采样（采样深度16bit，采样频率44.1kHz，双通道（环绕立体声），比特率，码率， 帧）

## H264编码算法

### 1.视频为什么要进行编码压缩

### 2.RGB和YUV

Y亮度参量，UV色度参量。Y分量占用字节多，UV分量占用字节少。

打包模式（package）；平面模式（planar）（实际开发）



### 3.视频压缩原理

1. 空间冗余；
2. 时间冗余；
3. 视觉冗余；
4. 编码冗余（信息熵冗余、哈夫曼编码）
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