A literal image was the secret message and a still image was the cover message.

以二值文字图像为待隐藏的秘密信息，以静止图像为隐秘载体。

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And what Mr. Newson talked about, on the day the nine black students enrolled at Central High in Little Rock and the thugs on the streets, the white thugs on the streets, attacked Mr. Newson and L. Alex Wilson, who was the editor at the Tri-State Defender in Memphis, and the message was clear, this is not your story, you're not going to cover it.

NPR: Book Examines Covering the Race Beat