We Chall-Training: LSB-Writeup

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We Chall-Training: LSB-Writeup

题目链接：http://www.wechall.net/challenge/training/stegano/LSB/index.php

原题如下：

由题目的名称LSB以及Hidden Hint可知该题为LSB隐写

LSB全称leastsignificant bit，最低有效位

PNG文件中的图像像数一般是由RGB三原色（红绿蓝）组成，每一种颜色占用8位，取值范围为0x00~0xFF，即有256种颜色，一共包含了256的3次方的颜色，即16777216种颜色

人类的眼睛可以区分约1000万种不同的颜色

这意味着人类的眼睛无法区分余下的颜色大约有6777216种

LSB隐写就是修改RGB颜色分量的最低二进制位（LSB），而人类的眼睛不会注意到这前后的变化

每个像数可以携带3比特的信息
更多LSB的资料http://www.tuicool.com/articles/qINzyum

用处理图像隐写的利器StegSolve打开图片：

通道调整为Red Plane 1时，出现了flag：

则flag即为CBLBAALNBOSR
2017-2-6 10:45;35