

In terms of data processing, LayoutLMv3 is identical to its predecessor LayoutLMv2, except that:
images need to be resized and normalized with channels in regular RGB format. LayoutLMv2 on the other hand normalizes the images internally and expects the channels in BGR format.
text is tokenized using byte-pair encoding (BPE), as opposed to WordPiece.
  Due to these differences in data preprocessing, one can use [LayoutLMv3Processor] which internally combines a [LayoutLMv3ImageProcessor] (for the image modality) and a [LayoutLMv3Tokenizer]/[LayoutLMv3TokenizerFast] (for the text modality) to prepare all data for the model.