Projective transformation of rational quadratic bzier curves 曲線的射影變換
Regular projective transformation 正則射影變換
Necessary and sufficient condition of 2 - dimension projective transformation being involution 二維射影變換是對(duì)合的充要條件
Some properties of projective transformation on projection plane producing by polar transformation 配極變換誘導(dǎo)的直射變換的若干性質(zhì)
First , we compute the larger spatial transformation . then , we refine the parameters using projective transformation . it is proved that this method can produce good result and fast speed 我們采用的是基于頻域仿射模型的光流方程,即首先計(jì)算比較大的空間變換,然后再對(duì)其進(jìn)行透視變換求精,實(shí)驗(yàn)證明這樣既可以獲得較好的效果,也提高了計(jì)算速度。
In two - view case , a method is presented for calculation 2d projective transformation and construction the virtual elements by combination of spatial points and lines . so more 3d invariants of object ' s spatial structures can be extracted from real elements and virtual eleme nts . ( 3 ) the geometric characteristics of 2d symmetric objects " in perspective images are lucubrated ( 2 )擴(kuò)展了2d射影變換矩陣的求解方法,將單純利用點(diǎn)集對(duì)應(yīng)的計(jì)算模式擴(kuò)展到利用直線集、點(diǎn)線組合等多種類型來(lái)建立兩個(gè)射影平面的對(duì)應(yīng)關(guān)系;總結(jié)了平面上基于點(diǎn)、直線元素可求解的多種3d不變量;提出了雙視圖下由點(diǎn)、直線元素的多種對(duì)應(yīng)關(guān)系求解2d射影變換來(lái)構(gòu)造“虛元素”的方法,結(jié)合“實(shí)元素”和“虛元素”可以提取更多的空間3d不變量。
Finally , a method is put forward to construct the nurbs curves on sphere , which extends the de boor recursive algorithm in r3 to one on the sphere by replacing the geodesic distances for the lines and studies their many geometric properties analogous to those in euclidean spaces , such as the differential property , the local property , the parameter invariance under a projective transformation , and so on 兩種方法均給出誤差估計(jì),使逼近螺線可達(dá)到任何預(yù)先給定的精確階。最后,給出球面nurbs曲線生成算法:用球面上測(cè)地線? ?劣大圓弧代替直線段,將歐氏空間r ~ 3中的deboor遞推算法推廣到球面上構(gòu)造曲線。
Second , more feature points are extracted for advanced registration based on projective transformation . compared with the ordinary method , our method has a better robust feature with higher accuracy , it also has a fully automatic feature so it need little human intervention in the whole process . the image segmentation , feature extraction , feature correspondency , and transformation model of multi - modality medical image registration are also studied in this paper 本研究的創(chuàng)新之處:針對(duì)rf和fa視網(wǎng)膜圖像的特點(diǎn),提出了新的血管細(xì)化的新方案;在特征點(diǎn)提取方面,提出了“三輪定心”這種新的特征點(diǎn)提取方法;提出了由“粗配”到“細(xì)配”的混合配準(zhǔn)方法;力矩主軸法用于圖像配準(zhǔn)參數(shù)的估計(jì)及對(duì)應(yīng)性尺度參數(shù)范圍的定值。
We introduce five topological characteristics and geometry characteristics that are invariant under projective transformation specially perspective projection . the definition of homograph is given by means of these characteristics , and then the recognizing method of the homograph is proposed according to the definition of homograph 接著,根據(jù)透視投影不變性提出了5個(gè)用來(lái)描述多邊形形狀的拓?fù)涮卣骱蛶缀翁卣?,這些特征在透視投影下是不變的,以這些特征給出了在透視投影下平面多邊形為類似形的定義。