Minecraft wiki entry for Block_entity_format, associated text: : The block entity's root tag.
 Base: The base color of the banner. See Banner#Block_data.
 Type: The type of the block entity. 0 is normal banner. 1 is ominous banner.
 Patterns: (May not exist) List of all patterns applied to the banner.
: An individual pattern.
 Pattern: The pattern id code. See Banner#Block_data.
 Color: The base color of the pattern. See Banner#Block_data.