  Steganography, as one of the three basic information security systems, has
long played an important role in safeguarding the privacy and confidentiality
of data in cyberspace. Audio is one of the most common means of information
transmission in our daily life. Thus it's of great practical significance to
using audio as a carrier of information hiding. At present, almost all
audio-based information hiding methods are based on carrier modification mode.
However, this mode is equivalent to adding noise to the original signal,
resulting in a difference in the statistical feature distribution of the
carrier before and after steganography, which impairs the concealment of the
entire system. In this paper, we propose an automatic audio generation-based
steganography(AAG-Stega), which can automatically generate high-quality audio
covers on the basis of the secret bits stream that needs to be embedded. In the
automatic audio generation process, we reasonably encode the conditional
probability distribution space of each sampling point and select the
corresponding signal output according to the bitstream to realize the secret
information embedding. We designed several experiments to test the proposed
model from the perspectives of information imperceptibility and information
hidden capacity. The experimental results show that the proposed model can
guarantee high hidden capacity and concealment at the same time.
