프로젝트에서는 HTML5 블러 이미지를 사용해야 합니다. 이전에는 GDI에 이를 구현하기 위해 미리 만들어진 구성 요소가 있습니다.
1.createImageData()
2.getImageData()
3.putImageData()
위의 세 가지 기능을 구현할 수 있습니다. 사용법과 비밀은 Baidu에 직접 가서 반복하지 않겠습니다. 설명이 별로 의미가 없습니다.
다음은 퍼지 알고리즘을 구현한 JS입니다. 실제로 분포 행렬인 또 다른 2B 레벨 알고리즘이 있는데, 이는 효율성을 몇 배로 증가시키지만 효과가 매우 낮고 페더링 효과가 강하지 않습니다.
구현 코드:
function stackBlurImage( imageID, canvasID, radius, blurAlphaChannel )
{
var img = document.getElementById( imageID );
var w = img.naturalWidth;
var h = img.naturalHeight;
var canvas = document.getElementById( canvasID );
canvas.style.width = w + "px";
canvas.style.height = h + "px";
canvas.width = w;
canvas.height = h;
var context = canvas.getContext("2d");
context.clearRect( 0, 0, w, h );
context.drawImage( img, 0, 0 );
if ( isNaN(radius) || radius < 1 ) return;
if ( blurAlphaChannel )
stackBlurCanvasRGBA( canvasID, 0, 0, w, h, radius );
else
stackBlurCanvasRGB( canvasID, 0, 0, w, h, radius );
}
function stackBlurCanvasRGBA( id, top_x, top_y, width, height, radius )
{
if ( isNaN(radius) || radius < 1 ) return;
radius |= 0 ;
var canvas = document.getElementById( id );
var context = canvas.getContext("2d");
var imageData;
시도 {
시도 {
imageData = context.getImageData( top_x, top_y, width, height );
} catch(e) {
시도 {
netscape.security.Privilege Manager.enablePrivilege( "UniversalBrowserRead");
imageData = context.getImageData( top_x, top_y, width, height );
} catch(e) {
Alert("로컬 이미지에 액세스할 수 없습니다");
새로 던지기 Error("로컬 이미지 데이터에 액세스할 수 없습니다: " e);
return;
}
}
} catch(e) {
Alert("이미지에 액세스할 수 없습니다");
새로운 오류 발생("이미지 데이터에 액세스할 수 없습니다: " e);
}
var Pixel = imageData.data;
var x, y, i, p, yp, yi, yw, r_sum, g_sum, b_sum, a_sum,
r_out_sum, g_out_sum, b_out_sum, a_out_sum,
r_in_sum, g_in_sum, b_in_sum, a_in_sum,
pr, pg, pb, pa, rbs;
var div = 반경 반경 1;
var w4 = 너비 << 2;
var widthMinus1 = 너비 - 1;
var heightMinus1 = 높이 - 1;
var radiusPlus1 = 반경 1;
var sumFactor = radiusPlus1 * ( radiusPlus1 1 ) / 2;
var stackStart = new BlurStack();
var stack = stackStart;
for ( i = 1; i < div; i )
{
stack = stack.next = new BlurStack( );
if ( i == radiusPlus1 ) var stackEnd = stack;
}
stack.next = stackStart;
var stackIn = null;
var stackOut = null;
yw = yi = 0;
var mul_sum = mul_table[radius];
var shg_sum = shg_table[radius];
for ( y = 0; y < height; y )
{
r_in_sum = g_in_sum = b_in_sum = a_in_sum = r_sum = g_sum = b_sum = a_sum = 0;
r_out_sum = radiusPlus1 * ( pr = 픽셀[yi] );
g_out_sum = radiusPlus1 * ( pg = 픽셀[yi 1] );
b_out_sum = radiusPlus1 * ( pb = 픽셀[yi 2] );
a_out_sum = radiusPlus1 * ( pa = 픽셀[yi 3] );
r_sum = sumFactor * pr;
g_sum = sumFactor * pg;
b_sum = sumFactor * pb;
a_sum = sumFactor * pa;
stack = stackStart;
for( i = 0; 나는 < radiusPlus1; i )
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack.a = pa;
스택 = stack.next ;
}
for( i = 1; i < radiusPlus1; i )
{
p = yi (( widthMinus1 < i ? widthMinus1 : i ) << 2 );
r_sum = ( stack.r = ( pr = 픽셀[p])) * ( rbs = radiusPlus1 - i );
g_sum = ( stack.g = ( pg = 픽셀[p 1])) * rbs;
b_sum = ( stack.b = ( pb = 픽셀[p 2])) * rbs;
a_sum = ( stack.a = ( pa = 픽셀[p 3])) * rbs;
r_in_sum = pr;
g_in_sum = pg;
b_in_sum = pb;
a_in_sum = pa;
stack = stack.next;
}
stackIn = stackStart;
stackOut = stackEnd;
for ( x = 0; x < width; x )
{
픽셀[yi 3] = pa = (a_sum * mul_sum) >> ; shg_sum;
if ( pa != 0 )
{
pa = 255 / pa;
픽셀[yi] = ((r_sum * mul_sum) >& gt;shg_sum) * pa;
픽셀[yi 1] = ((g_sum * mul_sum) >> shg_sum) * pa;
픽셀[yi 2] = ((b_sum * mul_sum) >> shg_sum) * pa;
} else {
픽셀[yi] = 픽셀[yi 1] = 픽셀[yi 2] = 0;
}
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
a_sum -= a_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
a_out_sum -= stackIn.a;
p = ( yw + ( ( p = x + radius + 1 ) < widthMinus1 ? p : widthMinus1 ) ) << 2;
r_in_sum += ( stackIn.r = pixels[p]);
g_in_sum += ( stackIn.g = pixels[p+1]);
b_in_sum += ( stackIn.b = pixels[p+2]);
a_in_sum += ( stackIn.a = pixels[p+3]);
r_sum += r_in_sum;
g_sum += g_in_sum;
b_sum += b_in_sum;
a_sum += a_in_sum;
stackIn = stackIn.next;
r_out_sum += ( pr = stackOut.r );
g_out_sum += ( pg = stackOut.g );
b_out_sum += ( pb = stackOut.b );
a_out_sum += ( pa = stackOut.a );
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
a_in_sum -= pa;
stackOut = stackOut.next;
yi += 4;
}
yw += width;
}
for ( x = 0; x < 너비; x )
{
g_in_sum = b_in_sum = a_in_sum = r_in_sum = g_sum = b_sum = a_sum = r_sum = 0;
yi = x << 2;
r_out_sum = radiusPlus1 * ( pr = 픽셀[yi]);
g_out_sum = radiusPlus1 * ( pg = 픽셀[yi 1]);
b_out_sum = radiusPlus1 * ( pb = 픽셀[yi 2] );
a_out_sum = radiusPlus1 * ( pa = 픽셀[yi 3]);
r_sum = sumFactor * pr;
g_sum = sumFactor * pg;
b_sum = sumFactor * pb;
a_sum = sumFactor * pa;
stack = stackStart;
for( i = 0; i < radiusPlus1; i )
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack.a = pa;
stack = stack.next;
}
yp = 너비;
for( i = 1; i <= radius; i )
{
yi = ( yp x ) << 2;
r_sum = ( stack.r = ( pr = 픽셀[yi])) * ( rbs = radiusPlus1 - i );
g_sum = ( stack.g = ( pg = 픽셀[yi 1 ])) * rbs;
b_sum = ( stack.b = ( pb = 픽셀[yi 2])) * rbs;
a_sum = ( stack.a = ( pa = 픽셀[yi 3])) * rbs;
r_in_sum = pr;
g_in_sum = pg;
b_in_sum = pb;
a_in_sum = pa;
스택 = stack.next;
if( i < heightMinus1 )
{
yp = width;
}
}
yi = x;
stackIn = stackStart;
stackOut = stackEnd ;
for ( y = 0; y < height; y )
{
p = yi << 2;
픽셀[p 3] = pa = (a_sum * mul_sum) >> shg_sum;
if ( pa > 0 )
{
pa = 255 / pa;
픽셀[p] = ((r_sum * mul_sum) >> ; shg_sum ) * 파;
픽셀[p 1] = ((g_sum * mul_sum) >> shg_sum ) * pa;
픽셀[p 2] = ((b_sum * mul_sum) >> shg_sum ) * pa;
} else {
픽셀[p] = 픽셀[p 1] = 픽셀[p 2] = 0;
}
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
a_sum -= a_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
a_out_sum -= stackIn.a;
p = ( x + (( ( p = y + radiusPlus1) < heightMinus1 ? p : heightMinus1 ) * width )) << 2;
r_sum += ( r_in_sum += ( stackIn.r = pixels[p]));
g_sum += ( g_in_sum += ( stackIn.g = pixels[p+1]));
b_sum += ( b_in_sum += ( stackIn.b = pixels[p+2]));
a_sum += ( a_in_sum += ( stackIn.a = pixels[p+3]));
stackIn = stackIn.next;
r_out_sum += ( pr = stackOut.r );
g_out_sum += ( pg = stackOut.g );
b_out_sum += ( pb = stackOut.b );
a_out_sum += ( pa = stackOut.a );
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
a_in_sum -= pa;
stackOut = stackOut.next;
yi += width;
}
}
context.putImageData( imageData, top_x, top_y );
}
function stackBlurCanvasRGB( id, top_x, top_y, width, height, radius )
{
if ( isNaN(radius) || radius < 1 ) return;
radius |= 0 ;
var canvas = document.getElementById( id );
var context = canvas.getContext("2d");
var imageData;
시도 {
시도 {
imageData = context.getImageData( top_x, top_y, width, height );
} catch(e) {
시도 {
netscape.security.PrivilegeManager.enablePrivilege( "UniversalBrowserRead");
imageData = context.getImageData( top_x, top_y, width, height );
} catch(e) {
Alert("로컬 이미지에 액세스할 수 없습니다");
새로 던지기 Error("로컬 이미지 데이터에 액세스할 수 없습니다: " e);
return;
}
}
} catch(e) {
Alert("이미지에 액세스할 수 없습니다");
새로운 오류 발생("이미지 데이터에 액세스할 수 없습니다: " e);
}
var Pixel = imageData.data;
var x, y, i, p, yp, yi, yw, r_sum, g_sum, b_sum,
r_out_sum, g_out_sum, b_out_sum,
r_in_sum, g_in_sum, b_in_sum,
pr, pg, pb, rbs;
var div = 반경 반경 1;
var w4 = 너비 << 2;
var widthMinus1 = 너비 - 1;
var heightMinus1 = 높이 - 1;
var radiusPlus1 = 반경 1;
var sumFactor = radiusPlus1 * ( radiusPlus1 1 ) / 2;
var stackStart = new BlurStack();
var stack = stackStart;
for ( i = 1; i < div; i )
{
stack = stack.next = new BlurStack( );
if ( i == radiusPlus1 ) var stackEnd = stack;
}
stack.next = stackStart;
var stackIn = null;
var stackOut = null;
yw = yi = 0;
var mul_sum = mul_table[radius];
var shg_sum = shg_table[radius];
for ( y = 0; y < height; y )
{
r_in_sum = g_in_sum = b_in_sum = r_sum = g_sum = b_sum = 0;
r_out_sum = radiusPlus1 * ( pr = 픽셀[yi] );
g_out_sum = radiusPlus1 * ( pg = 픽셀[yi 1] );
b_out_sum = radiusPlus1 * ( pb = 픽셀[yi 2] );
r_sum = sumFactor * pr;
g_sum = sumFactor * pg;
b_sum = sumFactor * pb;
stack = stackStart;
for( i = 0; 나는 < radiusPlus1; i)
{
stack.r = pr;
stack.g = pg;
stack.b = pb;
stack = stack.next;
}
for( i = 1; i < radiusPlus1; i++ )
{
p = yi + (( widthMinus1 < i ? widthMinus1 : i ) << 2 );
r_sum += ( stack.r = ( pr = pixels[p])) * ( rbs = radiusPlus1 - i );
g_sum += ( stack.g = ( pg = pixels[p+1])) * rbs;
b_sum += ( stack.b = ( pb = pixels[p+2])) * rbs;
r_in_sum += pr;
g_in_sum += pg;
b_in_sum += pb;
stack = stack.next;
}
stackIn = stackStart;
stackOut = stackEnd;
for ( x = 0; x < width; x++ )
{
pixels[yi] = (r_sum * mul_sum) >> shg_sum;
pixels[yi+1] = (g_sum * mul_sum) >> shg_sum;
pixels[yi+2] = (b_sum * mul_sum) >> shg_sum;
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn.g;
b_out_sum -= stackIn.b;
p = ( yw + ( ( p = x + radius + 1 ) < widthMinus1 ? p : widthMinus1 ) ) << 2;
r_in_sum += ( stackIn.r = pixels[p]);
g_in_sum += ( stackIn.g = pixels[p+1]);
b_in_sum += ( stackIn.b = pixels[p+2]);
r_sum += r_in_sum;
g_sum += g_in_sum;
b_sum += b_in_sum;
stackIn = stackIn.next;
r_out_sum += ( pr = stackOut.r );
g_out_sum += ( pg = stackOut.g );
b_out_sum += ( pb = stackOut.b );
r_in_sum -= pr;
g_in_sum -= pg;
b_in_sum -= pb;
stackOut = stackOut.next;
yi += 4;
}
yw += width;
}
for ( x = 0; x < 너비; x )
{
g_in_sum = b_in_sum = r_in_sum = g_sum = b_sum = r_sum = 0;
yi = x < ;< 2;
r_out_sum = radiusPlus1 * ( pr = 픽셀[yi]);
g_out_sum = radiusPlus1 * ( pg = 픽셀[yi 1]);
b_out_sum = radiusPlus1 * ( pb = 픽셀[yi 2] );
r_sum = sumFactor * pr;
g_sum = sumFactor * pg;
b_sum = sumFactor * pb;
stack = stackStart;
for( i = 0; i < radiusPlus1; i )
{
stack.r = pr;
stack.g = pg;
stack.b;
스택 = 스택.다음 ;
}
yp = 너비;
for( i = 1; i <= radius; i )
{
yi = ( yp x ) < < 2;
r_sum = ( stack.r = ( pr = 픽셀[yi])) * ( rbs = radiusPlus1 - i );
g_sum = ( stack.g = ( pg = 픽셀[yi 1 ])) * rbs;
b_sum = ( stack.b = ( pb = 픽셀[yi 2])) * rbs;
r_in_sum = pr;
g_in_sum = pg;
b_in_sum = pb;
stack = stack.next;
if( i < heightMinus1 )
{
yp = width;
}
}
yi = x;
stackIn = stackStart;
stackOut = stackEnd;
for ( y = 0; y < height; y )
{
p = 이 << 2;
픽셀[p] = (r_sum * mul_sum) >> shg_sum;
픽셀[p 1] = (g_sum * mul_sum) >> shg_sum;
픽셀[p 2] = (b_sum * mul_sum) >> shg_sum;
r_sum -= r_out_sum;
g_sum -= g_out_sum;
b_sum -= b_out_sum;
r_out_sum -= stackIn.r;
g_out_sum -= stackIn. g;
b_out_sum -= stackIn.b;
p = ( x (( ( p = y radiusPlus1) < heightMinus1 ? p : heightMinus1 ) * width )) << 2;
r_sum = ( r_in_sum = ( stackIn.r = 픽셀[p]));
g_sum = ( g_in_sum = ( stackIn.g = 픽셀[p 1]));
b_sum = ( b_in_sum = ( stackIn.b = 픽셀[p 2]));
stackIn = stackIn.next;
r_out_sum = ( pr = stackOut.r );
g_out_sum = ( pg = stackOut.g );
b_out_sum = ( pb = stackOut.b );
r_in_sum -= pr;
g_in_sum -= pg;
b _in_sum -= pb;
stackOut = stackOut.next;
yi = width;
}
}
context.putImageData( imageData, top_x, top_y );
}
함수 BlurStack()
{
this.r = 0;
this.g = 0;
this.b = 0;
this.a = 0;
this.next = null;
}
사용 방법: