How to split the picture and restore it in pdf

here"s the thing. Now there is a watermark on the first three pages of paf. I want to convert the picture recognition. Now the screenshot can be recognized, but how to restore the picture to its original pdf shape, please ask for instructions

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Apr.02,2021

you can try to operate pdf with itext and ask Duniang for specific operations

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e47738-438f1.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1e47738-438f1.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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