This paper addresses the subject of SQL Injection in a Microsoft SQL Server/IIS/Active
Server Pages environment, but most of the techniques discussed have equivalents in other
database environments. It should be viewed as a "follow up", or perhaps an appendix, to
the previous paper, "Advanced SQL Injection".
The paper covers in more detail some of the points described in its predecessor, providing
examples to clarify areas where the previous paper was perhaps unclear. An effective
method for privilege escalation is described that makes use of the openrowset function to
scan a network. A novel method for extracting information in the absence of helpful
error messages is described the use of time delays as a transmission channel. Finally, a
number of miscellaneous observations and useful hints are provided, collated from
responses to the original paper, and various conversations around the subject of SQL
injection in a SQL Server environment.
標簽:
Server
SQL
Injection
Microsoft
上傳時間:
2014-07-28
上傳用戶:xhz1993
摘 要
文章以空間監控系統為背景,深入研究了JPEG圖像壓縮標準的實現方法,并基于FPGA對其進行了實現和優化。文中給出了詳細的實現方法和優化過程,測試表明達到了很好的效果。
簡單介紹了有損靜態圖像壓縮當前有兩種比較流行的標準JPEG和JPEG2000。說明了用JPEG方法壓縮的原因。
介紹JPEG基本原理:JPEG對灰度圖像的壓縮處理過程主要包括:圖像分割,離散余弦變換(DCT),量化(Quantization),“Z”形排序(Zigzag scan),差分脈沖編碼調制(Differential Pulse Code Modulation,DPCM)對直流系數(DC),行程長度編碼(Run-Length Encoding,RLE)對交流系數(AC),霍夫曼(Huffman)編碼等。
JPEG標準的特點是離散余弦變換。
比較詳細介紹壓縮系統的構成和實現。實現提及步驟, JPEG壓縮模塊設計和編碼模塊實現細節。
標簽:
JPEG
FPGA
實現方法
監控系統
上傳時間:
2013-12-25
上傳用戶:410805624