JPH0970040A - Image companding method - Google Patents
Image companding methodInfo
- Publication number
- JPH0970040A JPH0970040A JP7224114A JP22411495A JPH0970040A JP H0970040 A JPH0970040 A JP H0970040A JP 7224114 A JP7224114 A JP 7224114A JP 22411495 A JP22411495 A JP 22411495A JP H0970040 A JPH0970040 A JP H0970040A
- Authority
- JP
- Japan
- Prior art keywords
- image information
- image
- equation
- boundary
- decompression
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 57
- 230000006835 compression Effects 0.000 claims description 28
- 238000007906 compression Methods 0.000 claims description 28
- 230000006837 decompression Effects 0.000 claims description 22
- 239000003086 colorant Substances 0.000 claims description 4
- 230000004069 differentiation Effects 0.000 abstract 2
- 238000010586 diagram Methods 0.000 description 10
- 230000005540 biological transmission Effects 0.000 description 3
- 239000000700 radioactive tracer Substances 0.000 description 2
- 239000003637 basic solution Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 229910001353 gamma loop Inorganic materials 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 239000012925 reference material Substances 0.000 description 1
Landscapes
- Compression Or Coding Systems Of Tv Signals (AREA)
- Compression Of Band Width Or Redundancy In Fax (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、画像圧縮伸張方法
に関し、特に、伝送、記録された画像の特徴点の位置情
報とこの位置の画像情報から、境界要素法を用いて自然
で正確な画像復元を行う画像圧縮伸張方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image compression / decompression method, and more particularly to a natural and accurate image using a boundary element method from position information of characteristic points of an image transmitted and recorded and image information of this position. The present invention relates to an image compression / decompression method for performing restoration.
【０００２】[0002]
【従来の技術】画素単位の画像情報の伝送方法として
は、画像の輝度レベル等の画像情報における輝度等高線
等の同一画像情報の位置を結ぶ等高線から抽出した特徴
点の位置情報とこの位置の画像情報とを伝送、記録およ
び画像復元に用いる画像圧縮伸張方法がある。2. Description of the Related Art As a method of transmitting image information on a pixel-by-pixel basis, position information of feature points extracted from contour lines connecting positions of the same image information such as luminance contour lines in image information such as luminance level of an image and the image at this position There is an image compression / expansion method used for transmitting, recording, and restoring images.
【０００３】本出願人は、例えば、輝度レベルまたは輝
度信号の画像情報の場合にその輝度等高線から抽出した
特徴点群の画像内の位置情報とこの位置の輝度レベルと
を伝送する画像圧縮伸張方法を、特願平５−３９４９２
号にて提案し詳述している。また、この輝度等高線間の
輝度レベルを決定する方法を、特願平６−１０７８１９
号にて提案し詳述している。The applicant of the present invention, for example, in the case of image information of a brightness level or a brightness signal, an image compression / expansion method for transmitting position information in the image of the feature point group extracted from the brightness contour line and the brightness level at this position. Japanese Patent Application No. 5-39492
It is proposed and detailed in the issue. A method for determining the brightness level between the brightness contour lines is disclosed in Japanese Patent Application No. 6-107819.
It is proposed and detailed in the issue.
【０００４】[0004]
【発明が解決しようとする課題】しかし、特願平６−１
０７８１９号にて提案した方法では、ある輝度レベル毎
での塗りつぶしと輝度等高線（等輝度線）の多角形近似
とを行っているため、輝度等高線を挟んだ明暗部の連続
性がとれずに、グラデーション（gradation ）などが不
自然になることがあった。[Patent Document 1] Japanese Patent Application No. 6-1
In the method proposed in No. 07819, since the filling for each certain brightness level and the polygonal approximation of the brightness contour line (contour line) are performed, the continuity of the bright and dark parts sandwiching the brightness contour line cannot be obtained, Sometimes the gradation was unnatural.
【０００５】本発明はかかる課題を解決すべくなされた
ものであって、画像情報が既知である複数のループに囲
まれた領域の画像情報を決定するにあたり、境界要素法
を用いてそのループ全体の影響を加味することにより、
特願平６−１０７８１９号にて提案した方法とは異なる
方法で、自然で正確な画像復元を行うことを目的とす
る。The present invention has been made to solve such a problem, and in determining the image information of the area surrounded by a plurality of loops in which the image information is known, the entire loop is determined by using the boundary element method. By adding the effect of
The purpose is to perform natural and accurate image restoration by a method different from the method proposed in Japanese Patent Application No. 6-107819.
【０００６】[0006]
【課題を解決するための手段】請求項１の画像圧縮伸張
方法では、伸張に際して、特徴点の位置を結ぶループに
ついて、このループを離散化した各要素の画像情報に基
づいてラプラスの方程式とグリーンの定理とによる境界
積分方程式から各要素の画像情報の法線方向微分を算定
し、この法線方向微分と各要素の画像情報とに基づいて
境界積分方程式から交差しない複数のループに囲まれた
領域（または領域内部の位置）の画像情報を決定するこ
とを特徴とする。According to the image compression / decompression method of claim 1, a Laplace equation and a Green's equation are calculated for a loop connecting the positions of feature points based on the image information of each element obtained by discretizing the loop. The theorem of and is used to calculate the differential in the normal direction of the image information of each element from the boundary integral equation, and based on this differential in the normal direction and the image information of each element, it is surrounded by multiple loops that do not intersect the boundary integral equation. The image information of the area (or the position inside the area) is determined.
【０００７】請求項２では、請求項１記載の画像圧縮伸
張方法において、伸張に際して、同一画像情報の特徴点
の位置を結ぶループについて、このループを離散化した
各要素の画像情報に基づいてラプラスの方程式とグリー
ンの定理とによる境界積分方程式から各要素の画像情報
の法線方向微分を算定し、この法線方向微分と各要素の
画像情報とに基づいて境界積分方程式から複数のループ
に囲まれた領域の画像情報を決定することを特徴とす
る。According to a second aspect of the present invention, in the image compressing / expanding method according to the first aspect, a Laplace based on the image information of each element obtained by discretizing the loop for connecting the positions of the characteristic points of the same image information at the time of the expansion. Of the image information of each element is calculated from the boundary integral equation by the equation of and the Green's theorem, and based on this normal direction differential and the image information of each element, the boundary integral equation is surrounded by multiple loops. It is characterized in that the image information of the closed region is determined.
【０００８】本発明では、輝度等高線間の輝度レベル等
を境界要素法を用いて決定する。境界要素法は有限要素
法と並んで電磁界、応力、熱、振動などの解析に用いら
れる手法で、均質な領域であれば境界のみの少ない要素
分割で済むこと、無限領域を扱えること等の利点を有す
る。In the present invention, the brightness level between the brightness contour lines is determined by using the boundary element method. The boundary element method is a method used along with the finite element method for analysis of electromagnetic fields, stresses, heat, vibrations, etc. Have advantages.
【０００９】境界要素法の基本となるのは、グリーンの
定理を基礎とする境界積分方程式である。離散化された
境界上の各要素についてポテンシャル（例えば、輝度レ
ベル等）またはその境界に関しての法線方向導関数（法
線方向微分）のどちらかが既知であれば、この境界積分
方程式から未知の方の値を算定することができ、その境
界で囲まれた領域内部の任意の点のポテンシャルを求め
て決定することができる。The boundary element method is based on the boundary integral equation based on Green's theorem. If either the potential (eg, brightness level) or the normal derivative (normal derivative) of the boundary is known for each element on the discretized boundary, the unknown unknown from this boundary integral equation. One of the values can be calculated, and the potential of any point inside the area surrounded by the boundary can be obtained and determined.
【００１０】本発明では、輝度レベル等の画像情報が既
知であるので、境界要素法で輝度レベル等の画像情報の
法線方向微分を算定し、これを用いて、領域内部の任意
の点の輝度レベル等の画像情報を決定するという手法を
とる。なお、参考資料としては、電気学会論文誌第１０
２巻第１０号（昭和５７年、「境界要素法における０−
１次混合離散化法について」、小貫天ほか）がある。In the present invention, since the image information such as the brightness level is already known, the normal direction differential of the image information such as the brightness level is calculated by the boundary element method, and this is used to calculate the arbitrary point inside the area. A method of determining image information such as a brightness level is used. In addition, as reference materials, the 10th journal of the Institute of Electrical Engineers of Japan
Volume 2 No. 10 (1982, "0-in the boundary element method
About the first-order mixing discretization method ”, Konuki Ten et al.).
【００１１】この決定方法によれば、特願平６−１０７
８１９号にて提案した方法とは異なり、ある１点の画像
情報の決定・設定についても輝度等高線等のループ全体
の影響を加味することになるので、自然で正確な画像の
復元が可能となる。According to this determination method, Japanese Patent Application No. 6-107
Unlike the method proposed in No. 819, since the influence of the entire loop such as the brightness contour line is added to the determination / setting of a certain point of image information, it is possible to restore the image naturally and accurately. .
【００１２】請求項３では、請求項１または請求項２記
載の画像圧縮伸張方法において、画像情報は、輝度信
号、３原色の原色信号、または、色差信号からなること
を特徴とする。According to a third aspect of the present invention, in the image compression / expansion method according to the first or second aspect, the image information comprises a luminance signal, primary color signals of three primary colors, or a color difference signal.
【００１３】画像圧縮伸張方法の画像情報は、主に輝度
レベルまたは輝度信号を対象とするが、３原色の原色信
号、色差または色差信号に対しても有効である。The image information of the image compression / expansion method mainly targets luminance levels or luminance signals, but is also effective for primary color signals of three primary colors, color differences or color difference signals.
【００１４】[0014]
【発明の実施の形態】以下、本発明を図面に示す実施形
態に基づいて説明する。画像の輝度レベル等の画像情報
における輝度等高線等の同一画像情報の位置を結ぶ等高
線から抽出した特徴点の位置情報とこの位置の画像情報
とを伝送、記録および画像復元に用いる画像圧縮伸張方
法に関するものである。図１は、本発明に係る画像圧縮
伸張方法の処理フロー図である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments shown in the drawings. The present invention relates to an image compression / decompression method used for transmitting, recording, and restoring image information of a feature point extracted from contour lines connecting positions of the same image information such as luminance contour lines in image information such as image brightness level, and image information at this position. It is a thing. FIG. 1 is a processing flow chart of an image compression / decompression method according to the present invention.
【００１５】本発明における境界要素法の画像情報への
応用については、電位が既知の２つのループ間に電荷や
電流の存在しない場合等における、その領域内部の任意
の点の電位を求める手法を適用でき、２次元ラプラス場
の問題として考えることができる。Regarding the application of the boundary element method to the image information in the present invention, a method for obtaining the electric potential at an arbitrary point inside the area when no electric charge or current exists between two loops of known electric potential is used. It can be applied and can be considered as a two-dimensional Laplace field problem.
【００１６】ポテンシャルｕ（例えば、輝度レベル）に
ついて、場の方程式であるラプラスの方程式は、数１で
表される。The Laplace's equation, which is the field equation for the potential u (for example, the brightness level), is expressed by the equation (1).
【００１７】[0017]
【数１】 [Equation 1]
【００１８】数１に対して、グリーンの定理を適用する
ことにより、数２で表される境界積分方程式を得る。By applying Green's theorem to the equation 1, the boundary integral equation expressed by the equation 2 is obtained.
【００１９】[0019]
【数２】 [Equation 2]
【００２０】ここで、Ｇ1 ＝（１／２π）ｌｎ（１／
ｒ）であり、ラプラスの方程式の基本解を表す。Ｇ2 ＝
（−ｒn ）／２πｒであり、Ｇ1 の法線方向微分であ
る。ｑはｕの法線方向微分、ｒは境界Γというループ全
体を見渡して積分を行う基準となる考察点Ｐから境界Γ
上の観測点Ｑまでの距離、ｒn は観測点Ｑにおける単位
法線ｎのｒ成分である。図２に考察領域Ωの例を示す。Here, G 1 = (1 / 2π) ln (1 /
r), which represents the basic solution of the Laplace equation. G 2 =
(−r n ) / 2πr, which is the differential in the normal direction of G 1 . q is the differential in the normal direction of u, and r is the boundary Γ.
The distance to the upper observation point Q, r n, is the r component of the unit normal line n at the observation point Q. FIG. 2 shows an example of the consideration region Ω.
【００２１】ｕp は考察点Ｐのポテンシャル、θは考察
点Ｐにおいてとられた内部領域に対する挟角で０〜２π
の値をとる。すなわち、図２のように考察点Ｐが考察領
域Ω中にある場合は２π、なめらかな境界上にある場合
はπ、直角をなす境界上にあるときはπ／２の値をと
る。U p is the potential of the consideration point P, θ is the included angle with respect to the internal region taken at the consideration point P, and is 0 to 2π.
Takes the value of. That is, as shown in FIG. 2, the consideration point P takes a value of 2π when it is in the consideration region Ω, π when it is on a smooth boundary, and π / 2 when it is on a right-angled boundary.
【００２２】この境界Γというループを図３のように複
数の節点ａによりＮ要素に離散化（図１の処理フローＦ
１）した場合は、数２は数３のように書き換えることが
できる。This boundary Γ loop is discretized into N elements by a plurality of nodes a as shown in FIG. 3 (processing flow F in FIG. 1).
In the case of 1), Equation 2 can be rewritten as Equation 3.
【００２３】[0023]
【数３】 (Equation 3)
【００２４】ここで、ｕj 及びｑj は、それぞれ離散化
後の各要素のポテンシャル及びその法線方向微分であ
る。各要素上のｕj 及びｑj は、各要素端の節点に１対
１に対応付けるものとする。なお、この離散化法にも、
種々の方法がある。Here, u j and q j are the potential of each element after discretization and its derivative in the normal direction. It is assumed that u j and q j on each element are in one-to-one correspondence with the nodes at the ends of each element. In addition, this discretization method also
There are various methods.
【００２５】いま、各要素についてｕj ，ｑj の片方が
既知の場合、各節点ａに観測点Ｑを置き、考察点Ｐを各
要素上に設けて数３の境界積分方程式をＮ個作成するこ
とで、未知の方のｕj ，ｑj を含むＮ元連立１次方程式
を得る（図１の処理フローＦ２）。要素上に設けた考察
点Ｐのポテンシャルｕp は、その要素両端のポテンシャ
ルから線形近似により求めてもよい。Now, if one of u j and q j is known for each element, an observation point Q is placed at each node a and a consideration point P is provided on each element to create N boundary integral equations of the equation 3. By doing so, an N-element simultaneous linear equation including the unknown u j and q j is obtained (processing flow F2 in FIG. 1). The potential u p of the consideration point P provided on the element may be obtained by linear approximation from the potentials at both ends of the element.
【００２６】これを解くことで、境界Γ上の各要素につ
いてのｕj ，ｑj を算定できる（図１の処理フローＦ
３）。By solving this, u j and q j for each element on the boundary Γ can be calculated (processing flow F in FIG. 1).
3).
【００２７】これらのｕj ，ｑj を数３の境界積分方程
式に代入することにより、境界Γで囲まれた領域Ω内部
の任意の点のポテンシャルは、考察点Ｐをその点に配置
したときのｕp として求めることができる（図１の処理
フローＦ４）。By substituting these u j and q j into the boundary integral equation of the equation 3, the potential at an arbitrary point inside the region Ω surrounded by the boundary Γ is obtained when the consideration point P is arranged at that point. Can be calculated as u p (processing flow F4 in FIG. 1).
【００２８】具体的に等高線方法に適用するには、以下
のようにする。等高線方法とは、図４または図５のよう
な複数のループの境界をもつ、斜線部のような領域内部
のポテンシャルを求める方法である。原則として、特徴
点が境界要素分割の節点になるが、要素の長さに著しい
不均等（例えば、１０倍程度）が生ずるとき改めて離散
化を行うこととする。The following is a concrete application to the contour line method. The contour line method is a method of obtaining a potential inside a region such as a hatched portion having a boundary of a plurality of loops as shown in FIG. 4 or 5. As a general rule, the feature points are the nodes of the boundary element division, but when the element lengths are significantly uneven (for example, about 10 times), discretization is performed again.
【００２９】このとき、ループは複数であるが、それら
に囲まれて決定される領域は１つであるので、数学的に
は１つのループで囲まれた閉領域と同じように扱うこと
ができる。At this time, although there are a plurality of loops, the number of areas surrounded by the loops and determined is one, so that it can be treated mathematically in the same manner as a closed area surrounded by one loop. .
【００３０】また、境界条件については、特徴点を結ぶ
線（例えば、多角形近似された輝度等高線）が境界にな
るのでｕj はすべて既知、ｑj はすべて未知ということ
になる。このｑj を算定して、斜線領域内部の任意の点
のポテンシャル（輝度レベル）を決定する（図１の処理
フローＦ３、Ｆ４）。Regarding the boundary conditions, since lines connecting feature points (for example, brightness contour lines approximated by polygons) are boundaries, all u j are known and all q j are unknown. This q j is calculated to determine the potential (luminance level) of an arbitrary point inside the shaded area (processing flow F3, F4 in FIG. 1).
【００３１】図６は、請求項１に係る画像圧縮伸張方法
を適用する領域を示す。画像の輝度レベル等の画像情報
における輝度等高線等の同一画像情報の位置を結ぶ等高
線から抽出した特徴点の位置を結ぶ２つの多角形ループ
に囲まれた領域が図６の斜線領域であり、請求項１に係
る画像圧縮伸張方法を適用する領域である。Ｎ＝１０と
している。符号ｋ４〜ｋ９は、各特徴点の輝度レベルで
あり、境界上の各節点の輝度レベルである。特徴点を節
点として利用している。この斜線領域内部にある任意の
点の輝度レベルを本発明により決定し設定することがで
きる。FIG. 6 shows an area to which the image compression / decompression method according to claim 1 is applied. An area surrounded by two polygonal loops connecting the positions of the feature points extracted from the contour line connecting the positions of the same image information such as the brightness contour line in the image information such as the brightness level of the image is the hatched area in FIG. This is an area to which the image compression / decompression method according to Item 1 is applied. N = 10. Reference numerals k4 to k9 are the brightness levels of the respective feature points and the brightness levels of the nodes on the boundary. The feature points are used as nodes. The brightness level of any point inside this shaded area can be determined and set by the present invention.
【００３２】図７は、請求項２に係る画像圧縮伸張方法
を適用する領域を示す。画像の輝度レベル等の画像情報
における輝度等高線等の同一画像情報の位置を結ぶ等高
線から抽出した同一画像情報の特徴点の位置を結ぶ２つ
の多角形ループに囲まれた領域が図７の斜線領域であ
り、請求項２に係る画像圧縮伸張方法を適用する領域で
ある。この多角形ループは、多角形近似された輝度等高
線を表している。Ｎ＝１０としている。符号ｋ５，ｋ９
は、各特徴点の輝度レベルであり、境界上の各節点の輝
度レベルである。特徴点を節点として利用している。こ
の斜線領域内部にある任意の点の輝度レベルを本発明に
より決定し設定することができる。FIG. 7 shows an area to which the image compression / decompression method according to claim 2 is applied. The area surrounded by two polygonal loops connecting the positions of the feature points of the same image information extracted from the contour lines connecting the positions of the same image information such as the brightness contour lines in the image information such as the brightness level of the image is the shaded area in FIG. And is an area to which the image compression / decompression method according to claim 2 is applied. This polygon loop represents a polygon-approximated luminance contour line. N = 10. Codes k5, k9
Is the brightness level of each feature point and the brightness level of each node on the boundary. The feature points are used as nodes. The brightness level of any point inside this shaded area can be determined and set by the present invention.
【００３３】同一画像情報の特徴点の位置を結ぶ多角形
ループを使用しているので、要素上に設けた考察点Ｐの
ポテンシャルｕp はこの同一画像情報（輝度レベル）の
値となり、その要素両端のポテンシャルから線形近似等
により求める手間がはぶけて、計算量を減らすことがで
きる。Since a polygonal loop connecting the positions of the characteristic points of the same image information is used, the potential u p of the consideration point P provided on the element becomes the value of this same image information (luminance level), and the element The amount of calculation can be reduced because the time required for linear approximation or the like from the potentials at both ends is eliminated.
【００３４】本発明が実施される具体的構成例として、
図８に圧縮側ブロック図、図９に伸張側ブロック図を示
す。As a concrete configuration example in which the present invention is implemented,
FIG. 8 shows a compression side block diagram, and FIG. 9 shows a decompression side block diagram.
【００３５】図８の画像源１からの画像信号はＡ／Ｄ変
換器２でＡ／Ｄ変換され、輝度成分Ｙは輝度レベルとし
て輝度メモリ３に供給され記録される。輝度メモリ３の
出力信号は、輝度等高線トレーサ４に供給され、特願平
６−１０７８１９号にて提案した方法によって輝度等高
線が抽出され、更にこの輝度等高線から抽出された多角
形近似による特徴点の多角形近似アドレスリスト５が出
力される。また、輝度メモリ３の出力信号はエッジ検出
器６に供給され、平滑化・微分フィルタリング・膨張処
理を行うためのエッジマスク８が生成される。The image signal from the image source 1 in FIG. 8 is A / D converted by the A / D converter 2, and the luminance component Y is supplied to the luminance memory 3 as a luminance level and recorded. The output signal of the luminance memory 3 is supplied to the luminance contour line tracer 4, the luminance contour line is extracted by the method proposed in Japanese Patent Application No. 6-107819, and the characteristic points by the polygonal approximation extracted from the luminance contour line are extracted. The polygonal approximate address list 5 is output. Further, the output signal of the luminance memory 3 is supplied to the edge detector 6, and an edge mask 8 for performing smoothing / differential filtering / expansion processing is generated.
【００３６】次に、多角形近似アドレスリスト５の示す
座標値（位置情報）とエッジマスク８等の示す情報とに
基づく特徴点群の位置情報や画像情報等が、マルチプレ
クサ９を通り、符号化器１０に送られハフマンコード等
の公知の符号に変換された後に、伝送路１１を通じて伸
張側に伝送される。Next, the position information and image information of the characteristic point group based on the coordinate values (position information) indicated by the polygonal approximate address list 5 and the information indicated by the edge mask 8 and the like pass through the multiplexer 9 and are encoded. After being sent to the device 10 and converted into a known code such as a Huffman code, it is transmitted to the decompression side through the transmission line 11.
【００３７】伝送路１１によって伝送された符号は図９
の伸張側の復号化器１２によって多角形近似アドレスリ
スト１３に復号される。多角形近似アドレスリスト１３
から得られる特徴点群の輝度レベルと位置情報に基づい
て、輝度成分再生器１４内にて図１の処理フローを経
て、図６や図７のような複数の多角形ループに囲まれた
領域内部の任意の位置の輝度レベルが決定される。The code transmitted by the transmission line 11 is shown in FIG.
It is decoded into a polygonal approximate address list 13 by the decoder 12 on the decompression side. Polygonal approximate address list 13
A region surrounded by a plurality of polygonal loops as shown in FIGS. 6 and 7 through the processing flow of FIG. 1 in the luminance component regenerator 14 based on the luminance level and position information of the feature point group obtained from The brightness level of any position inside is determined.
【００３８】再生された輝度レベル等の画像情報は、駆
動回路１５で映像信号に変換、駆動され、ＴＶモニタ１
６に復元画像として表示される。圧縮側、伸張側の各々
の構成については、前述の特願平５−３９４９２号や特
願平６−１０７８１９号にて提案された構成を参考にで
きる。The image information such as the reproduced luminance level is converted into a video signal by the drive circuit 15 and driven, and the TV monitor 1
6 is displayed as a restored image. With respect to the respective structures on the compression side and the expansion side, the structures proposed in the above-mentioned Japanese Patent Application Nos. 5-39492 and 6-107819 can be referred to.
【００３９】本実施例では、輝度レベルまたは輝度信号
を画像情報としたが、３原色（赤青緑）の各原色の濃淡
や原色信号のうち１つ以上の信号、色差または色差信
号、色相、明度、彩度などを画像情報として、本発明に
係る画像圧縮伸張方法を行ってもよい。また、複数のル
ープに囲まれた領域に限らず、１つのループで囲まれた
領域について、その領域内部の画像情報を決定するため
に本発明を適用してもよい。In the present embodiment, the brightness level or the brightness signal is used as the image information, but the density of each of the three primary colors (red, blue, and green) or one or more signals among the primary color signals, the color difference or the color difference signal, the hue, The image compression / expansion method according to the present invention may be performed using brightness, saturation and the like as image information. Further, the present invention may be applied not only to the area surrounded by a plurality of loops but also to the area surrounded by one loop to determine the image information inside the area.
【００４０】なお、本発明は上記実施形態の他に種々の
実施形態が考えられるが、それらはすべて本発明に含ま
れるものである。It should be noted that the present invention is conceivable in various embodiments other than the above-mentioned embodiment, but all of them are included in the present invention.
【００４１】[0041]
【発明の効果】以上説明したように、本発明では輝度レ
ベル等の画像情報が既知の複数のループ間の画像情報を
求めるにあたり、境界要素法を適用することにより、特
願平６−１０７８１９号にて提案した方法とは異なり、
ループ全体の影響を加味した、自然で正確な画像を復元
することができる。As described above, according to the present invention, the boundary element method is applied in obtaining the image information between a plurality of loops in which the image information such as the brightness level is known, and the Japanese Patent Application No. 6-107819 is applied. Unlike the method proposed in
It is possible to restore a natural and accurate image that takes into account the influence of the entire loop.
【図１】本発明に係る画像圧縮伸張方法の処理フロー図FIG. 1 is a processing flowchart of an image compression / expansion method according to the present invention.
【図２】考察領域を示す図FIG. 2 is a diagram showing a study area.
【図３】境界をＮ要素に離散化した考察領域を表す図FIG. 3 is a diagram showing a consideration region in which a boundary is discretized into N elements.
【図４】本発明に係る画像圧縮伸張方法を適用する領域
を表す図FIG. 4 is a diagram showing an area to which an image compression / expansion method according to the present invention is applied.
【図５】本発明に係る画像圧縮伸張方法を適用する領域
を表す図FIG. 5 is a diagram showing a region to which an image compression / expansion method according to the present invention is applied.
【図６】請求項１に係る画像圧縮伸張方法を適用する領
域を表す図FIG. 6 is a diagram showing a region to which the image compression / decompression method according to claim 1 is applied.
【図７】請求項２に係る画像圧縮伸張方法を適用する領
域を表す図FIG. 7 is a diagram showing a region to which the image compression / decompression method according to claim 2 is applied.
【図８】画像圧縮伸張方法の処理を行う圧縮側ブロック
図FIG. 8 is a block diagram of a compression side that performs processing of an image compression / decompression method.
【図９】画像圧縮伸張方法の処理を行う伸張側ブロック
図FIG. 9 is a block diagram of a decompression side that performs processing of an image compression / decompression method.
１…画像源、２…Ａ／Ｄ変換器、３…輝度メモリ、４…
輝度等高線トレーサ、５，１３…多角形近似アドレスリ
スト、６…エッジ検出器、８…エッジマスク、９…マル
チプレクサ、１０…符号化器、１１…伝送路、１２…復
号化器、１４…輝度成分再生器、１５…駆動回路、１６
…ＴＶモニタ、Ｐ…考察点、Ｑ…観測点、ａ…節点、ｋ
４〜ｋ９…輝度レベル、ｎ…単位法線、ｒ…ＰＱ間の距
離、Γ…境界、Ω…考察領域。1 ... Image source, 2 ... A / D converter, 3 ... Luminance memory, 4 ...
Intensity contour tracer, 5, 13 ... Polygonal approximation address list, 6 ... Edge detector, 8 ... Edge mask, 9 ... Multiplexer, 10 ... Encoder, 11 ... Transmission path, 12 ... Decoder, 14 ... Luminance component Regenerator, 15 ... Drive circuit, 16
... TV monitor, P ... Consideration point, Q ... Observation point, a ... Node, k
4 to k9 ... Luminance level, n ... Unit normal line, r ... Distance between PQs, .GAMMA .... Boundary, .OMEGA.
Claims (3)
輝度等高線等の同一画像情報の位置を結ぶ等高線から抽
出した特徴点の位置情報とこの位置の前記画像情報とを
伝送、記録および画像復元に用いる画像圧縮伸張方法に
おいて、 伸張に際して、前記特徴点の位置を結ぶループについ
て、このループを離散化した各要素の画像情報に基づい
てラプラスの方程式とグリーンの定理とによる境界積分
方程式から前記各要素の画像情報の法線方向微分を算定
し、この法線方向微分と前記各要素の画像情報とに基づ
いて前記境界積分方程式から交差しない複数の前記ルー
プに囲まれた領域の画像情報を決定することを特徴とす
る画像圧縮伸張方法。1. Position information of a feature point extracted from a contour line connecting positions of the same image information such as a brightness contour line in image information such as a brightness level of an image and the image information at this position are transmitted, recorded and image restored. In the image compression / decompression method used, at the time of decompression, a loop connecting the positions of the characteristic points is extracted from the boundary integral equation by Laplace's equation and Green's theorem based on the image information of each element obtained by discretizing the loop. Of the image information of the normal direction is calculated, and the image information of the area surrounded by the plurality of loops that do not intersect from the boundary integral equation is determined based on the normal direction differential and the image information of each element. An image compression / decompression method characterized by the above.
点の位置を結ぶループについて、このループを離散化し
た各要素の画像情報に基づいてラプラスの方程式とグリ
ーンの定理とによる境界積分方程式から前記各要素の画
像情報の法線方向微分を算定し、この法線方向微分と前
記各要素の画像情報とに基づいて前記境界積分方程式か
ら複数の前記ループに囲まれた領域の画像情報を決定す
ることを特徴とする請求項１記載の画像圧縮伸張方法。2. At the time of decompression, a loop connecting the positions of the characteristic points of the same image information is calculated from the boundary integral equation based on the Laplace equation and Green's theorem based on the image information of each element obtained by discretizing the loop. The normal direction differential of the image information of each element is calculated, and the image information of the area surrounded by the plurality of loops is determined from the boundary integral equation based on the normal direction differential and the image information of each element. The image compression / decompression method according to claim 1, wherein
色信号、または、色差信号からなる請求項１または請求
項２記載の画像圧縮伸張方法。3. The image compression / expansion method according to claim 1, wherein the image information comprises a luminance signal, primary color signals of three primary colors, or a color difference signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7224114A JPH0970040A (en) | 1995-08-31 | 1995-08-31 | Image companding method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7224114A JPH0970040A (en) | 1995-08-31 | 1995-08-31 | Image companding method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0970040A true JPH0970040A (en) | 1997-03-11 |
Family
ID=16808760
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7224114A Pending JPH0970040A (en) | 1995-08-31 | 1995-08-31 | Image companding method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0970040A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002532723A (en) * | 1998-12-17 | 2002-10-02 | ポールヘマス インコーポレイテッド | Method and apparatus for determining electromagnetic field characteristics within a volume |
| US8831094B2 (en) | 2010-09-01 | 2014-09-09 | Electronics And Telecommunications Research Institute | Video processing method and apparatus based on multiple texture images |
| KR101481451B1 (en) * | 2010-09-01 | 2015-01-13 | 한국전자통신연구원 | Method and apparatus for image processing based on multiple texture image |
| CN111318696A (en) * | 2018-12-13 | 2020-06-23 | 通用电气公司 | Method of Molten Pool Monitoring Using Green's Theorem |
-
1995
- 1995-08-31 JP JP7224114A patent/JPH0970040A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002532723A (en) * | 1998-12-17 | 2002-10-02 | ポールヘマス インコーポレイテッド | Method and apparatus for determining electromagnetic field characteristics within a volume |
| US8831094B2 (en) | 2010-09-01 | 2014-09-09 | Electronics And Telecommunications Research Institute | Video processing method and apparatus based on multiple texture images |
| KR101481451B1 (en) * | 2010-09-01 | 2015-01-13 | 한국전자통신연구원 | Method and apparatus for image processing based on multiple texture image |
| CN111318696A (en) * | 2018-12-13 | 2020-06-23 | 通用电气公司 | Method of Molten Pool Monitoring Using Green's Theorem |
| CN111318696B (en) * | 2018-12-13 | 2022-09-06 | 通用电气公司 | Molten pool monitoring method using Green's theorem |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6639691B2 (en) | Block-matching algorithm for color interpolation | |
| US8724894B1 (en) | Colorization of digital imagery | |
| US6856323B2 (en) | Layered image rendering | |
| US6897977B1 (en) | Lossy method for compressing pictures and video | |
| WO2004034088A3 (en) | Method and system for limited frequency seismic imaging | |
| US20030117411A1 (en) | Texture mapping method and apparatus | |
| KR20090013934A (en) | Method and system for generating immersion for two-dimensional still image and method for factor adjustment for generating immersion, image content analysis method and scaling parameter prediction method | |
| EP0886436A3 (en) | Compression of mosaiced images | |
| CN111684234B (en) | Method for determining repair length and device for determining repair length | |
| JP3568026B2 (en) | How to evaluate video image quality | |
| DE50206894D1 (en) | METHOD FOR COMPRESSING AND DECOMPRIMATING VIDEO DATA | |
| US7529418B2 (en) | Geometry and view assisted transmission of graphics image streams | |
| WO2014126032A1 (en) | Image processing device, image processing method, and recording medium | |
| KR101819984B1 (en) | Image synthesis method in real time | |
| JP3543103B2 (en) | Color image processing method and processing apparatus | |
| KR20010024416A (en) | Static image generation method and device | |
| JP4539964B2 (en) | Image segmentation | |
| JPS62206556A (en) | How to artificially color images | |
| Forssén et al. | Channel representation of colour images | |
| US5140314A (en) | Image assembly | |
| Hasche et al. | Using ACES Look Modification Transforms (LMTs) in VFX Environments–Part 2: Gamut Mapping | |
| DE50302209D1 (en) | METHOD OF DETERMINING WEIGHT FACTORS FOR COLORING A COLORING TEXEL FOR A FOOTPRINT | |
| JP3375079B2 (en) | Image compression device | |
| JP3375078B2 (en) | Image compression device | |
| KR101516757B1 (en) | Image interpolation apparatus and control method thereof |