PDF file is a format file with multi-layer structure, which is characterized in that the file can be based on text (such as the file generated by word) or image (such as the file generated by scanning); Double-layer PDF file means that the file content contains both text layer and image layer, and their positions correspond to each other.

What are the advantages of using a double-layer PDF file?

PDF file format has become an international standard, and more and more industries and units are using it. It is characterized by a multi-layer structure, including a layer and a text layer. In this way, the original layout effect (including official seal and signature) can be 100%, and functions such as selection, copying and full-text retrieval can be supported through the lower text information. Therefore, double-layer PDF gives consideration to both visual effect and retrieval convenience, which greatly facilitates the management of electronic documents.

What does double-layer PDF file processing mean?

Image files such as tif, jpg, bmp, gif, png, and single-layer PDF (image) are processed and output as double-layer (layer and text layer) PDF files that can be searched in full text.