Handling the processing response (Document AI)
https://cloud.google.com/document-ai/docs/handle-response
#Document_AI_(GCP)
Text, layout, and quality scores
google-cloud-documentaiの返り値を見ながら参照した
text
The text field contains the text that is recognized by Document AI.
This text doesn't contain any layout structure other than spaces, tabs, and line feeds.
This is the only field that stores a document's textual information. Other fields can refer to parts of the text field by position (startIndex and endIndex).
entities（パースする場合）
OCRだとなかった
pages
Note: pages[].pageNumber is 1-based, not 0-based.
blocks
text_segmentsを参照すると、textのどこと対応するかが分かる（と思われる）
paragraphs
lines
tokens
これらの違いを囲みで示している
Forms and tables