After analyzing the two roi coding methods of jpeg2000 standard , their shortcoming is pointed out , and then a novel roi image coding method with utilizing information hiding technique is proposed . in this scheme , some coded information of the background is embedded into the redundant bits of the roi coefficients . the relative quality of rois and background can be adjusted by changing the quantity of embedded information 感興趣區(qū)編碼是jpeg2000標(biāo)準(zhǔn)所提供的一項(xiàng)重要特性,本文對標(biāo)準(zhǔn)中規(guī)定的兩種感興趣區(qū)編碼方法進(jìn)行了分析,指出其不足之處,而后創(chuàng)造性地提出利用信息隱藏技術(shù)來對其進(jìn)行補(bǔ)充,將部分背景區(qū)的編碼信息隱藏在感興趣區(qū)系數(shù)的冗余位,通過控制嵌入量可以調(diào)節(jié)感興趣區(qū)和背景區(qū)的相對質(zhì)量。
According to research of redundant signed digit ( rsd ) calibration theory of pipelined adc , a novel out of range detection rsd technique is provided . when input signal is out of the adc ’ s range , the technique can detect this situation and the wrong output word is avoided 然后,在深入分析冗余位算法的基礎(chǔ)上,提出了新型的校正算法,針對傳統(tǒng)算法不能判斷信號超出adc處理范圍的不足,增加了溢出判斷功能,既能有效校正比較器的失調(diào),又防止了信號溢出時(shí)的誤碼輸出,保證了系統(tǒng)的性能。
Under 0 . 35um si - cmos process , considering the trade off of accuracy and speed in the adc , 2 . 5 - bit were converted in the first stage of the pipeline . using the improved calibration scheme and full difference structure and bottom - plant sampling technique to reduce the errors of the 10 - bit ( 2 . 5 + 1 . 5 5 + 3 ) , 100msample / s pipeline adc 在0 . 35 m工藝水平下,通過折衷考慮提高系統(tǒng)線性度和降低功耗的要求,將流水線第一級精度取為2 . 5位,采用改進(jìn)的冗余位算法,并結(jié)合全差分結(jié)構(gòu),下底板采樣等技術(shù)對一個(gè)( 2 . 5 + 1 . 5 5 + 3 )結(jié)構(gòu)的10位100msample / s流水線adc系統(tǒng)進(jìn)行校正。