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README.md

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 # TL;DR
 
+## Details for Pix2Struct-RefExp: (Based on their [pre-processing](https://github.com/google-research/pix2struct/blob/main/pix2struct/preprocessing/convert_refexp.py))
+
+-> __Input__: An image with a bounding box drawn on it around a candidate object and a header containing the referring expression (stored in the image feature).
+
+-> __Output__: A boolean flag (parse feature) indicating whether the candidate object is the correct referent of the referring expression.
+
 Pix2Struct is an image encoder - text decoder model that is trained on image-text pairs for various tasks, including image captionning and visual question answering. The full list of available models can be found on the Table 1 of the paper:
 
 ![Table 1 - paper](https://s3.amazonaws.com/moonup/production/uploads/1678712985040-62441d1d9fdefb55a0b7d12c.png)