Methods, computer devices, and non-transitory computer-readable record media for learning of watermarking model using complex attack

A watermarking model learning method executed by a computer device, the computer device including at least one processor configured to execute computer-readable instructions stored in a memory, and the watermarking model learning method comprises:

• dividing, by the at least one processor, epochs for learning of a watermarking model into at least two stages;
• setting, by the at least one processor, at least one target attack type to each stage among the at least two stages, the setting includes setting a first threshold number of the at least one target attack type set to an earlier stage to be greater than a second threshold number of the at least one target attack type set to a later stage, and the at least two stages including the earlier stage and the later stage;
• and
• performing, by the at least one processor, learning of the watermarking model based on the at least two stages and the setting.