Error Code:
TimedText-TTMLUnresolvedPixelPositioning
Error Message:
Missing tts:extend Warning
Example: The 'tts:extent' attribute for element 'region' on line 11 uses pixel positioning, but there is no extent on the tt element. Positioning will be ignored.
Definition:
When pixel positioning is used, tts:extent must be defined in root container in order for positional data to apply and define the meaning of a pixel. The positional information will be ignored.
Solution:
Do not use pixel values to define regions or font sizes. Only use percentage values.
Use tts:textAlign and tts:displayAlign for positioning along with static values for tts:extent and tts:origin.
tts:fontSize shall be defined as 100%.
For more information, please refer to the Timed Text General Style Guide.