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获取图像边界(不是图像本身,而是非白色像素)的好方法是什么?我正在使用 javascript,所以如果可以的话,请尽量将算法保持在该范围内。
例如,我如何获得所有 x 和 y 点的列表/两个列表,其中存在于此(一组)对象边界上的点:
请注意,应包括内部部分,但应排除完全位于内部的颜色缺失(如孔洞)。
因此,结果将是两个包含 x 和 y 点(对于像素)的列表,它们将构造一个类似于此的对象:
下面是我是如何“实现”它的。虽然它适用于所有凹面物体,但如果您尝试将它用于具有某些凸面的更复杂物体,它不可避免地会失败。
片段:
var _PI = Math.PI, _HALF_PI = Math.PI / 2, _TWO_PI = 2 * Math.PI;
var _radius = 10, _damp = 75, _center = new THREE.Vector3(0, 0, 0);
var _phi = _PI / 2, _theta = _theta = _PI / 7;
var _sceneScreenshot = null, _dirty = true;
var _tmpCan = document.createElement("canvas"),
_tmpCtx = _tmpCan.getContext("2d");
var scene = document.getElementById("scene"),
sw = scene.width, sh = scene.height;
var _scene = new THREE.Scene();
var _renderer = new THREE.WebGLRenderer({ canvas: scene, alpha: true, antialias: true });
_renderer.setPixelRatio(window.devicePixelRatio);
_renderer.setSize(sw, sh);
var _camera = new THREE.PerspectiveCamera(35, sw / sh, .1, 1000);
_tmpCan.width = sw; _tmpCan.height = sh;
_scene.add(new THREE.HemisphereLight(0x999999, 0x555555, 1));
_scene.add(new THREE.AmbientLight(0x404040));
var _camLight = new THREE.PointLight(0xdfdfdf, 1.8, 300, 2);
_scene.add(_camLight);
var geometry = new THREE.BoxBufferGeometry( 1, 1, 1 );
var material = new THREE.MeshPhysicalMaterial( { color: 0x2378d3, opacity: .7 } );
var cube = new THREE.Mesh( geometry, material );
_scene.add( cube );
function initialize() {
document.body.appendChild(_tmpCan);
_tmpCan.style.position = "absolute";
_tmpCan.style.left = "8px";
_tmpCan.style.top = "8px";
_tmpCan.style.pointerEvents = "none";
addListeners();
updateCamera();
animate();
}
function addListeners() {
/* mouse events */
var scene = document.getElementById("scene");
scene.oncontextmenu = function(e) {
e.preventDefault();
}
scene.onmousedown = function(e) {
e.preventDefault();
mouseTouchDown(e.pageX, e.pageY, e.button);
}
scene.ontouchstart = function(e) {
if (e.touches.length !== 1) {
return;
}
e.preventDefault();
mouseTouchDown(e.touches[0].pageX, e.touches[0].pageY, e.touches.length, true);
}
function mouseTouchDown(pageX, pageY, button, touch) {
_mouseX = pageX; _mouseY = pageY;
_button = button;
if (touch) {
document.ontouchmove = function(e) {
if (e.touches.length !== 1) {
return;
}
mouseTouchMove(e.touches[0].pageX, e.touches[0].pageY, e.touches.length, true);
}
document.ontouchend = function() {
document.ontouchmove = null;
document.ontouchend = null;
}
} else {
document.onmousemove = function(e) {
mouseTouchMove(e.pageX, e.pageY, _button);
}
document.onmouseup = function() {
document.onmousemove = null;
document.onmouseup = null;
}
}
}
function mouseTouchMove(pageX, pageY, button, touch) {
var dx = pageX - _mouseX,
dy = pageY - _mouseY;
_phi += dx / _damp;
// _theta += dy / _damp;
_phi %= _TWO_PI;
if (_phi < 0) {
_phi += _TWO_PI;
}
// var maxTheta = _HALF_PI - _HALF_PI * .8,
// minTheta = -_HALF_PI + _HALF_PI * .8;
// if (_theta > maxTheta) {
// _theta = maxTheta;
// } else if (_theta < minTheta) {
// _theta = minTheta;
// }
updateCamera();
_dirty = true;
// updateLabels();
_mouseX = pageX;
_mouseY = pageY;
}
}
function updateCamera() {
// var radius = _radius + (Math.sin(_theta % _PI)) * 10;
var radius = _radius;
var y = radius * Math.sin(_theta),
phiR = radius * Math.cos(_theta);
var z = phiR * Math.sin(_phi),
x = phiR * Math.cos(_phi);
_camera.position.set(x, y, z);
_camLight.position.set(x, y, z);
_camera.lookAt(_center);
}
function updateLabels() {
if (_sceneScreenshot === null) {
return;
}
var tmpImg = new Image();
tmpImg.onload = function() {
_tmpCtx.drawImage(tmpImg, 0, 0, sw, sh);
var imgData = _tmpCtx.getImageData(0, 0, sw, sh);
var data = imgData.data;
var firstXs = [];
var lastXs = [];
for (var y = 0; y < sh; y++) {
var firstX = -1;
var lastX = -1;
for (var x = 0; x < sw; x++) {
var i = (x + y * sw) * 4;
var sum = data[i] + data[i + 1] + data[i + 2];
if (firstX === -1) {
if (sum > 3) {
firstX = x;
}
} else {
if (sum > 3) {
lastX = x;
}
}
}
if (lastX === -1 && firstX >= 0) {
lastX = firstX;
}
firstXs.push(firstX);
lastXs.push(lastX);
}
var firstYs = [];
var lastYs = [];
for (var x = 0; x < sw; x++) {
var firstY = -1;
var lastY = -1;
for (var y = 0; y < sh; y++) {
var i = (x + y * sw) * 4;
var sum = data[i] + data[i + 1] + data[i + 2];
if (firstY === -1) {
if (sum < 759) {
firstY = y;
}
} else {
if (sum < 759) {
lastY = y;
}
}
}
if (lastY === -1 && firstY >= 0) {
lastY = firstY;
}
firstYs.push(firstY);
lastYs.push(lastY);
}
postLoad(firstXs, lastXs, firstYs, lastYs);
}
tmpImg.src = _sceneScreenshot;
function postLoad(firstXs, lastXs, firstYs, lastYs) {
_tmpCtx.clearRect(0, 0, sw, sh);
_tmpCtx.beginPath();
for (var y = 0; y < sh; y++) {
_tmpCtx.moveTo(firstXs[y], y);
_tmpCtx.lineTo(lastXs[y], y);
}
/* TODO REMOVE BELOW TODO */
_tmpCtx.strokeStyle = 'black';
console.log(_tmpCtx.globalAlpha);
_tmpCtx.stroke();
/* TODO REMOVE ABOVE TODO */
_tmpCtx.beginPath();
for (var x = 0; x < sw; x++) {
_tmpCtx.moveTo(x, firstYs[x]);
_tmpCtx.lineTo(x, lastYs[x]);
}
/* TODO REMOVE BELOW TODO */
_tmpCtx.strokeStyle = 'black';
_tmpCtx.stroke();
/* TODO REMOVE ABOVE TODO */
var imgData = _tmpCtx.getImageData(0, 0, sw, sh);
var data = imgData.data;
for (var i = 0, iLen = data.length; i < iLen; i += 4) {
if (data[i + 3] < 200) {
data[i + 3] = 0;
}
/* TODO remove v TODO */
else { data[i + 3] = 120; }
}
_tmpCtx.putImageData(imgData, 0, 0);
}
}
function animate () {
cube.rotation.x += 0.001;
cube.rotation.y += 0.001;
_renderer.render(_scene, _camera);
if (_dirty) {
_sceneScreenshot = _renderer.domElement.toDataURL();
updateLabels();
_dirty = false;
}
requestAnimationFrame( animate );
}
initialize();
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/92/three.js"></script>
<canvas id="scene" width="400" height="300"></canvas>
var _PI = Math.PI, _HALF_PI = Math.PI / 2, _TWO_PI = 2 * Math.PI;
var _radius = 10, _damp = 75, _center = new THREE.Vector3(0, 0, 0);
var _phi = _PI / 2, _theta = _theta = 0;
var _sceneScreenshot = null, _dirty = true;
var _tmpCan = document.createElement("canvas"),
_tmpCtx = _tmpCan.getContext("2d");
var scene = document.getElementById("scene"),
sw = scene.width, sh = scene.height;
var _scene = new THREE.Scene();
var _renderer = new THREE.WebGLRenderer({ canvas: scene, alpha: true, antialias: true });
_renderer.setPixelRatio(window.devicePixelRatio);
_renderer.setSize(sw, sh);
var _camera = new THREE.PerspectiveCamera(35, sw / sh, .1, 1000);
_tmpCan.width = sw; _tmpCan.height = sh;
_scene.add(new THREE.HemisphereLight(0x999999, 0x555555, 1));
_scene.add(new THREE.AmbientLight(0x404040));
var _camLight = new THREE.PointLight(0xdfdfdf, 1.8, 300, 2);
_scene.add(_camLight);
var geometry = new THREE.BoxBufferGeometry( 1, 1, 1 );
var material = new THREE.MeshPhysicalMaterial( { color: 0x2378d3, opacity: .7 } );
var cube = new THREE.Mesh( geometry, material );
_scene.add( cube );
var geometry = new THREE.BoxBufferGeometry( 1, 1, 1 );
var material = new THREE.MeshPhysicalMaterial( { color: 0xc36843, opacity: .7 } );
var cube2 = new THREE.Mesh( geometry, material );
cube2.position.x = -.75;
cube2.position.y = .75
_scene.add( cube2 );
var geometry = new THREE.BoxBufferGeometry( 1, 1, 1 );
var material = new THREE.MeshPhysicalMaterial( { color: 0x43f873, opacity: .7 } );
var cube3 = new THREE.Mesh( geometry, material );
cube3.position.x = -.25;
cube3.position.y = 1.5;
_scene.add( cube3 );
var geometry = new THREE.BoxBufferGeometry( 1, 1, 1 );
var material = new THREE.MeshPhysicalMaterial( { color: 0x253621, opacity: .7 } );
var cube4 = new THREE.Mesh( geometry, material );
cube4.position.x = 1;
cube4.position.y = .35;
_scene.add( cube4 );
function initialize() {
document.body.appendChild(_tmpCan);
_tmpCan.style.position = "absolute";
_tmpCan.style.left = "200px";
_tmpCan.style.top = "0px";
_tmpCan.style.pointerEvents = "none";
addListeners();
updateCamera();
animate();
}
function addListeners() {
/* mouse events */
var scene = document.getElementById("scene");
scene.oncontextmenu = function(e) {
e.preventDefault();
}
scene.onmousedown = function(e) {
e.preventDefault();
mouseTouchDown(e.pageX, e.pageY, e.button);
}
scene.ontouchstart = function(e) {
if (e.touches.length !== 1) {
return;
}
e.preventDefault();
mouseTouchDown(e.touches[0].pageX, e.touches[0].pageY, e.touches.length, true);
}
function mouseTouchDown(pageX, pageY, button, touch) {
_mouseX = pageX; _mouseY = pageY;
_button = button;
if (touch) {
document.ontouchmove = function(e) {
if (e.touches.length !== 1) {
return;
}
mouseTouchMove(e.touches[0].pageX, e.touches[0].pageY, e.touches.length, true);
}
document.ontouchend = function() {
document.ontouchmove = null;
document.ontouchend = null;
}
} else {
document.onmousemove = function(e) {
mouseTouchMove(e.pageX, e.pageY, _button);
}
document.onmouseup = function() {
document.onmousemove = null;
document.onmouseup = null;
}
}
}
function mouseTouchMove(pageX, pageY, button, touch) {
var dx = pageX - _mouseX,
dy = pageY - _mouseY;
_phi += dx / _damp;
// _theta += dy / _damp;
_phi %= _TWO_PI;
if (_phi < 0) {
_phi += _TWO_PI;
}
// var maxTheta = _HALF_PI - _HALF_PI * .8,
// minTheta = -_HALF_PI + _HALF_PI * .8;
// if (_theta > maxTheta) {
// _theta = maxTheta;
// } else if (_theta < minTheta) {
// _theta = minTheta;
// }
updateCamera();
_dirty = true;
// updateLabels();
_mouseX = pageX;
_mouseY = pageY;
}
}
function updateCamera() {
// var radius = _radius + (Math.sin(_theta % _PI)) * 10;
var radius = _radius;
var y = radius * Math.sin(_theta),
phiR = radius * Math.cos(_theta);
var z = phiR * Math.sin(_phi),
x = phiR * Math.cos(_phi);
_camera.position.set(x, y, z);
_camLight.position.set(x, y, z);
_camera.lookAt(_center);
}
function updateLabels() {
if (_sceneScreenshot === null) {
return;
}
var tmpImg = new Image();
tmpImg.onload = function() {
_tmpCtx.drawImage(tmpImg, 0, 0, sw, sh);
var imgData = _tmpCtx.getImageData(0, 0, sw, sh);
var data = imgData.data;
var firstXs = [];
var lastXs = [];
for (var y = 0; y < sh; y++) {
var firstX = -1;
var lastX = -1;
for (var x = 0; x < sw; x++) {
var i = (x + y * sw) * 4;
var sum = data[i] + data[i + 1] + data[i + 2];
if (firstX === -1) {
if (sum > 3) {
firstX = x;
}
} else {
if (sum > 3) {
lastX = x;
}
}
}
if (lastX === -1 && firstX >= 0) {
lastX = firstX;
}
firstXs.push(firstX);
lastXs.push(lastX);
}
var firstYs = [];
var lastYs = [];
for (var x = 0; x < sw; x++) {
var firstY = -1;
var lastY = -1;
for (var y = 0; y < sh; y++) {
var i = (x + y * sw) * 4;
var sum = data[i] + data[i + 1] + data[i + 2];
if (firstY === -1) {
if (sum > 3) {
firstY = y;
}
} else {
if (sum > 3) {
lastY = y;
}
}
}
if (lastY === -1 && firstY >= 0) {
lastY = firstY;
}
firstYs.push(firstY);
lastYs.push(lastY);
}
postLoad(firstXs, lastXs, firstYs, lastYs);
}
tmpImg.src = _sceneScreenshot;
function postLoad(firstXs, lastXs, firstYs, lastYs) {
_tmpCtx.clearRect(0, 0, sw, sh);
_tmpCtx.beginPath();
for (var y = 0; y < sh; y++) {
_tmpCtx.moveTo(firstXs[y], y);
_tmpCtx.lineTo(lastXs[y], y);
}
/* TODO REMOVE BELOW TODO */
_tmpCtx.strokeStyle = 'black';
console.log(_tmpCtx.globalAlpha);
_tmpCtx.stroke();
/* TODO REMOVE ABOVE TODO */
_tmpCtx.beginPath();
for (var x = 0; x < sw; x++) {
_tmpCtx.moveTo(x, firstYs[x]);
_tmpCtx.lineTo(x, lastYs[x]);
}
/* TODO REMOVE BELOW TODO */
_tmpCtx.strokeStyle = 'black';
_tmpCtx.stroke();
/* TODO REMOVE ABOVE TODO */
var imgData = _tmpCtx.getImageData(0, 0, sw, sh);
var data = imgData.data;
for (var i = 0, iLen = data.length; i < iLen; i += 4) {
if (data[i + 3] < 200) {
data[i + 3] = 0;
}
/* TODO remove v TODO */
else { data[i + 3] = 120; }
}
_tmpCtx.putImageData(imgData, 0, 0);
}
}
function animate () {
cube.rotation.x += 0.001;
cube.rotation.y += 0.001;
cube2.rotation.x -= 0.001;
cube2.rotation.y += 0.001;
cube3.rotation.x += 0.001;
cube3.rotation.y -= 0.001;
cube4.rotation.x -= 0.001;
cube4.rotation.y -= 0.001;
_renderer.render(_scene, _camera);
if (_dirty) {
_sceneScreenshot = _renderer.domElement.toDataURL();
updateLabels();
_dirty = false;
}
requestAnimationFrame( animate );
}
initialize();
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/92/three.js"></script>
<canvas id="scene" width="400" height="300"></canvas>
您可以通过上面的 jsfiddle 看到这个复杂的凸图像的内部在内部失败。
因此,问题仍然存在:如果您愿意,什么是创建图像(忽略孔洞) mask 的好方法,该 mask 将覆盖背景为白色的任何复杂/凸物体的所有外部图像的组成部分不是白色的?谢谢
最佳答案
这是一个使用 flood-fill 的解决方案算法用白色覆盖外部区域,用黑色覆盖其余区域。
请记住,这是一个非常幼稚的实现,有很多优化可以完成(例如,通过计算边界矩形并仅在其中填充,另一种方法是使用 32-bit arrays 进行实际的像素分配填充时)。
另一件需要注意的事情是,填充总是从左上角开始,如果对象当前覆盖该像素,它将不起作用(但是您可以选择另一个像素开始)。
我删除了触摸处理程序和一些其他项目以保持示例简短。updateMask
函数是创建掩码的地方。
function createCube(color, x, y){
const geo = new THREE.BoxBufferGeometry( 1, 1, 1 );
const mat = new THREE.MeshPhysicalMaterial( { color: color, opacity: 1 } );
const mesh = new THREE.Mesh(geo, mat);
mesh.position.x = x;
mesh.position.y = y;
return mesh;
}
const c_main = document.getElementById("main");
const c_mask = document.getElementById("mask");
const ctx_mask = c_mask.getContext("2d");
ctx_mask.fillStyle = "#000";
const cw = c_main.width, ch = c_main.height;
const TWO_PI = Math.PI * 2;
const damp = 75, radius = 10, animspeed = 0.001;
const center = new THREE.Vector3(0, 0, 0);
let x1 = 0;
let phi = Math.PI / 2;
const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera(35, cw / ch, 0.1, 1000);
const renderer = new THREE.WebGLRenderer({ canvas: c_main, alpha: true, antialias: false });
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(cw, ch);
const camLight = new THREE.PointLight(0xdfdfdf, 1.8, 300, 2);
scene.add(new THREE.HemisphereLight(0x999999, 0x555555, 1));
scene.add(new THREE.AmbientLight(0x404040));
scene.add(camLight);
const cubes = [];
cubes.push(createCube(0x2378d3, 0, 0));
cubes.push(createCube(0xc36843, -0.75, 0.75));
cubes.push(createCube(0x43f873, -0.25, 1.5));
cubes.push(createCube(0x253621, 1, 0.35));
scene.add(...cubes);
function initialize() {
c_main.addEventListener("mousedown", mouseDown, false);
updateCamera();
animate();
}
function updateMask(){
//First, fill the canvas with black
ctx_mask.globalCompositeOperation = "source-over";
ctx_mask.fillRect(0,0, cw, ch);
//Then using the composite operation "destination-in" the canvas is made transparent EXCEPT where the new image is drawn.
ctx_mask.globalCompositeOperation = "destination-in";
ctx_mask.drawImage(c_main, 0, 0);
//Now, use a flood fill algorithm of your choice to fill the outer transparent field with white.
const idata = ctx_mask.getImageData(0,0, cw, ch);
const array = idata.data;
floodFill(array, 0, 0, cw, ch);
ctx_mask.putImageData(idata, 0, 0);
//The only transparency left are in the "holes", we make these black by using the composite operation "destination-over" to paint black behind everything.
ctx_mask.globalCompositeOperation = "destination-over";
ctx_mask.fillRect(0,0, cw, ch);
}
function mouseDown(e){
e.preventDefault();
x1 = e.pageX;
const button = e.button;
document.addEventListener("mousemove", mouseMove, false);
document.addEventListener("mouseup", mouseUp, false);
}
function mouseUp(){
document.removeEventListener("mousemove", mouseMove, false);
document.removeEventListener("mouseup", mouseUp, false);
}
function mouseMove(e){
const x2 = e.pageX;
const dx = x2 - x1;
phi += dx/damp;
phi %= TWO_PI;
if( phi < 0 ){
phi += TWO_PI;
}
x1 = x2;
updateCamera();
}
function updateCamera() {
const x = radius * Math.cos(phi);
const y = 0;
const z = radius * Math.sin(phi);
camera.position.set(x, y, z);
camera.lookAt(center);
camLight.position.set(x, y, z);
}
function animate(){
cubes[0].rotation.x += animspeed;
cubes[0].rotation.y += animspeed;
cubes[1].rotation.x -= animspeed;
cubes[1].rotation.y += animspeed;
cubes[2].rotation.x += animspeed;
cubes[2].rotation.y -= animspeed;
cubes[3].rotation.x -= animspeed;
cubes[3].rotation.y -= animspeed;
renderer.render(scene, camera);
updateMask();
requestAnimationFrame(animate);
}
const FILL_THRESHOLD = 254;
//Quickly adapted flood fill from http://www.adammil.net/blog/v126_A_More_Efficient_Flood_Fill.html
function floodStart(array, x, y, width, height){
const M = width * 4;
while(true){
let ox = x, oy = y;
while(y !== 0 && array[(y-1)*M + x*4 + 3] < FILL_THRESHOLD){ y--; }
while(x !== 0 && array[y*M + (x-1)*4 + 3] < FILL_THRESHOLD){ x--; }
if(x === ox && y === oy){ break; }
}
floodFill(array, x, y, width, height);
}
function floodFill(array, x, y, width, height){
const M = width * 4;
let lastRowLength = 0;
do{
let rowLength = 0, sx = x;
let idx = y*M + x*4 + 3;
if(lastRowLength !== 0 && array[idx] >= FILL_THRESHOLD){
do{
if(--lastRowLength === 0){ return; }
}
while(array[ y*M + (++x)*4 + 3]);
sx = x;
}
else{
for(; x !== 0 && array[y*M + (x-1)*4 + 3] < FILL_THRESHOLD; rowLength++, lastRowLength++){
const idx = y*M + (--x)*4;
array[idx] = 255;
array[idx + 1] = 255;
array[idx + 2] = 255;
array[idx + 3] = 255;
if( y !== 0 && array[(y-1)*M + x*4 + 3] < FILL_THRESHOLD ){
floodStart(array, x, y-1, width, height);
}
}
}
for(; sx < width && array[y*M + sx*4 + 3] < FILL_THRESHOLD; rowLength++, sx++){
const idx = y*M + sx*4;
array[idx] = 255;
array[idx + 1] = 255;
array[idx + 2] = 255;
array[idx + 3] = 255;
}
if(rowLength < lastRowLength){
for(let end=x+lastRowLength; ++sx < end; ){
if(array[y*M + sx*4 + 3] < FILL_THRESHOLD){
floodFill(array, sx, y, width, height);
}
}
}
else if(rowLength > lastRowLength && y !== 0){
for(let ux=x+lastRowLength; ++ux<sx; ){
if(array[(y-1)*M + ux*4 + 3] < FILL_THRESHOLD){
floodStart(array, ux, y-1, width, height);
}
}
}
lastRowLength = rowLength;
}
while(lastRowLength !== 0 && ++y < height);
}
initialize();
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/92/three.js"></script>
<canvas id="main" width="300" height="200"></canvas>
<canvas id="mask" width="300" height="200"></canvas>
关于javascript - 获取具有白色背景的图像中复杂对象的边界(js),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/50260162/
我正在尝试学习 Knockout 并尝试创建一个照片 uploader 。我已成功将一些图像存储在数组中。现在我想回帖。在我的 knockout 码(Javascript)中,我这样做: 我在 Jav
我正在使用 php 编写脚本。我的典型问题是如何在 mysql 中添加一个有很多替代文本和图像的问题。想象一下有机化学中具有苯结构的描述。 最有效的方法是什么?据我所知,如果我有一个图像,我可以在数据
我在两个图像之间有一个按钮,我想将按钮居中到图像高度。有人可以帮帮我吗? Entrar
下面的代码示例可以在这里查看 - http://dev.touch-akl.com/celebtrations/ 我一直在尝试做的是在 Canvas 上绘制 2 个图像(发光,然后耀斑。这些图像的链接
请检查此https://jsfiddle.net/rhbwpn19/4/ 图像预览对于第一篇帖子工作正常,但对于其他帖子则不然。 我应该在这里改变什么? function readURL(input)
我对 Canvas 有疑问。我可以用单个图像绘制 Canvas ,但我不能用单独的图像绘制每个 Canvas 。- 如果数据只有一个图像,它工作正常,但数据有多个图像,它不工作你能帮帮我吗? va
我的问题很简单。如何获取 UIImage 的扩展类型?我只能将图像作为 UIImage 而不是它的名称。图像可以是静态的,也可以从手机图库甚至文件路径中获取。如果有人可以为此提供一点帮助,将不胜感激。
我有一个包含 67 个独立路径的 SVG 图像。 是否有任何库/教程可以为每个路径创建单独的光栅图像(例如 PNG),并可能根据路径 ID 命名它们? 最佳答案 谢谢大家。我最终使用了两个答案的组合。
我想将鼠标悬停在一张图片(音乐专辑)上,然后播放一张唱片,所以我希望它向右移动并旋转一点,当它悬停时我希望它恢复正常动画片。它已经可以向右移动,但我无法让它随之旋转。我喜欢让它尽可能简单,因为我不是编
Retina iOS 设备不显示@2X 图像,它显示 1X 图像。 我正在使用 Xcode 4.2.1 Build 4D502,该应用程序的目标是 iOS 5。 我创建了一个测试应用(主/细节)并添加
我正在尝试从头开始以 Angular 实现图像 slider ,并尝试复制 w3school基于图像 slider 。 下面我尝试用 Angular 实现,谁能指导我如何使用 Angular 实现?
我正在尝试获取图像的图像数据,其中 w= 图像宽度,h = 图像高度 for (int i = x; i imageData[pos]>0) //Taking data (here is the pr
我的网页最初通过在 javascript 中动态创建图像填充了大约 1000 个缩略图。由于权限问题,我迁移到 suPHP。现在不用标准 标签本身 我正在通过这个 php 脚本进行检索 $file
我正在尝试将 python opencv 图像转换为 QPixmap。 我按照指示显示Page Link我的代码附在下面 img = cv2.imread('test.png')[:,:,::1]/2
我试图在这个 Repository 中找出语义分割数据集的 NYU-v2 . 我很难理解图像标签是如何存储的。 例如,给定以下图像: 对应的标签图片为: 现在,如果我在 OpenCV 中打开标签图像,
import java.util.Random; class svg{ public static void main(String[] args){ String f="\"
我有一张 8x8 的图片。 (位图 - 可以更改) 我想做的是能够绘制一个形状,给定一个 Path 和 Paint 对象到我的 SurfaceView 上。 目前我所能做的就是用纯色填充形状。我怎样才
要在页面上显示图像,你需要使用源属性(src)。src 指 source 。源属性的值是图像的 URL 地址。 定义图像的语法是: 在浏览器无法载入图像时,替换文本属性告诉读者她们失去的信息。此
**MMEditing是基于PyTorch的图像&视频编辑开源工具箱,支持图像和视频超分辨率(super-resolution)、图像修复(inpainting)、图像抠图(matting)、
我正在尝试通过资源文件将图像插入到我的程序中,如下所示: green.png other files 当我尝试使用 QImage 或 QPixm
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