本节主要是对可变元数据标签的含义和用法进行说明。
This section contains notes about the interpretation and usage of various metadata tags.
S9.1 高质量（HIGH_QUALITY）模式和快速（FAST）模式
许多相机后处理模块可能具有HIGH_QUALITY、FAST或OFF操作模式。这些模块通常也有一个‘可用模式’标签，用于表示给定设备有哪些操作模式可用。下面是实现这些模式的一般策略：
Many camera post-processing blocks may be listed as having HIGH_QUALITY, FAST, and OFF operating modes. These blocks will typically also have an ‘available modes’ tag representing which of these operating modes are available on a given device. The general policy regarding implementing these modes is as follows:
无法禁用的硬件模块的操作模式控制器不能将
OFF列在其自身的‘可用模式’标签中。Operating mode controls of hardware blocks that cannot be disabled must not list OFF in their corresponding ‘available modes’ tags.
如果硬件模块可以被禁用，
OFF将总是包含其具有的‘可用模式’标签中。OFF will always be included in their corresponding ‘available modes’ tag if it is possible to disable that hardware block.
对于设备支持的所有后处理模块，
FAST必须始终被包含在对应的‘可用模式’标签中。如果一个后处理模块还有不符合FAST模式帧率要求的更慢、更高质量的操作模式，HIGH_QUALITY应该被包含在对应的‘可用模式’标签中以表示该操作模式。FAST must always be included in the ‘available modes’ tags for all post-processing blocks supported on the device. If a post-processing block also has a slower and higher quality operating mode that does not meet the framerate requirements for FAST mode, HIGH_QUALITY should be included in the ‘available modes’ tag to represent this operating mode.