Ogre中使用Opencv加载视频作为纹理贴图
2014-03-17 21:30
375 查看
增强现实中经常要用到真实的2D视频图片再配合虚拟对象(如三维模型)结合,以达到增强现实的效果。这里使用Ogre结合Opencv来实现
在开始前要先了解到纹理贴图的长宽必须是2的n次方,所以假如加载的视频没有达到这个值,必须做一下resize
1.创建动态纹理、背景框矩形,并添加到场景
在CreateScene中加入如下代码
[cpp] view
plaincopy
void CreateScene()
{
MaterialPtr material = MaterialManager::getSingleton().create(
"DynamicTextureMaterial", // name
ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME);
material->getTechnique(0)->getPass(0)->createTextureUnitState("DynamicBg");
material->getTechnique(0)->getPass(0)->setDepthCheckEnabled(false);
material->getTechnique(0)->getPass(0)->setDepthWriteEnabled(false);
material->getTechnique(0)->getPass(0)->setLightingEnabled(false);
// Create background rectangle covering the whole screen
Rectangle2D* rect = new Rectangle2D(true);
rect->setCorners(-1.0, 1.0, 1.0, -1.0);
rect->setMaterial("DynamicTextureMaterial");
// Render the background before everything else
rect->setRenderQueueGroup(RENDER_QUEUE_BACKGROUND);
// Hacky, but we need to set the bounding box to something big
// NOTE: If you are using Eihort (v1.4), please see the note below on setting the bounding box
rect->setBoundingBox(AxisAlignedBox(-100000.0*Vector3::UNIT_SCALE, 100000.0*Vector3::UNIT_SCALE));
// Attach background to the scene
SceneNode* node = mSceneMgr->getRootSceneNode()->createChildSceneNode("Background");
node->attachObject(rect);
//add other scene node here
}
2.初始化视频图像获取相关数据
[cpp] view
plaincopy
<pre name="code" class="cpp">void InitVideoQuery(char *szVideoPath)
{
m_szVideoPath = szVideoPath;
m_pFileCamer=cvCreateFileCapture(szVideoPath );
m_pVideoImage=cvQueryFrame(m_pFileCamer);
m_pDrawImage=cvCreateImage(cvSize(1024,1024),8,3);
m_pTex=TextureManager::getSingleton().createManual("DynamicBg","General",
TEX_TYPE_2D,m_pDrawImage->width,m_pDrawImage->height,1,0,PF_A8B8G8R8,TU_WRITE_ONLY);</pre>}<br>
<br>
<pre></pre>
<pre></pre>
<p> </p>
<p>3.更新顶点缓存</p>
<pre class="cpp" name="code">void UpdateTextureImage()
{
m_pVideoImage=cvQueryFrame(m_pFileCamer);
if(m_pDrawImage==0)
{
cvReleaseCapture(&m_pFileCamer);
m_pFileCamer=cvCreateFileCapture(m_szVideoPath);
m_pVideoImage=cvQueryFrame(m_pFileCamer);
}
cvShowImage("img",m_pVideoImage);
cvResize(m_pVideoImage,m_pDrawImage);
HardwarePixelBufferSharedPtr buffer=m_pTex->getBuffer(0,0);
buffer->lock(HardwareBuffer::HBL_DISCARD);
const PixelBox &pb = buffer->getCurrentLock();
uint32 *data = static_cast<uint32*>(pb.data);
size_t height = pb.getHeight();
size_t width = pb.getWidth();
size_t pitch = pb.rowPitch; // Skip between rows of image
for(size_t y=0; y<m_pDrawImage->height; ++y)
{
unsigned char *pImgLine=(unsigned char *)(m_pDrawImage->imageData+y*m_pDrawImage->widthStep);
for(size_t x=0; x<m_pDrawImage->width; ++x)
{
// 0xRRGGBB -> fill the buffer with yellow pixels
unsigned char B=pImgLine[3*x];
unsigned char G=pImgLine[3*x+1];
unsigned char R=pImgLine[3*x+2];
uint32 pixel=(R<<16)+(G<<8)+(B);
data[pitch*y + x] =pixel ;
}
}
buffer->unlock();
}</pre>
<p><br>
</p>
<p> </p>
<p>值得一提的是,在更新顶点缓存的过程中,即lock到unlock之间,由于操作硬件缓存效率低,为了提高效率,应该尽量减少代码的操作量,可选的做法是在外面将数据打包好,然后在更新的时候直接memcpy</p>
<p><br>
</p>
<pre></pre>
在开始前要先了解到纹理贴图的长宽必须是2的n次方,所以假如加载的视频没有达到这个值,必须做一下resize
1.创建动态纹理、背景框矩形,并添加到场景
在CreateScene中加入如下代码
[cpp] view
plaincopy
void CreateScene()
{
MaterialPtr material = MaterialManager::getSingleton().create(
"DynamicTextureMaterial", // name
ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME);
material->getTechnique(0)->getPass(0)->createTextureUnitState("DynamicBg");
material->getTechnique(0)->getPass(0)->setDepthCheckEnabled(false);
material->getTechnique(0)->getPass(0)->setDepthWriteEnabled(false);
material->getTechnique(0)->getPass(0)->setLightingEnabled(false);
// Create background rectangle covering the whole screen
Rectangle2D* rect = new Rectangle2D(true);
rect->setCorners(-1.0, 1.0, 1.0, -1.0);
rect->setMaterial("DynamicTextureMaterial");
// Render the background before everything else
rect->setRenderQueueGroup(RENDER_QUEUE_BACKGROUND);
// Hacky, but we need to set the bounding box to something big
// NOTE: If you are using Eihort (v1.4), please see the note below on setting the bounding box
rect->setBoundingBox(AxisAlignedBox(-100000.0*Vector3::UNIT_SCALE, 100000.0*Vector3::UNIT_SCALE));
// Attach background to the scene
SceneNode* node = mSceneMgr->getRootSceneNode()->createChildSceneNode("Background");
node->attachObject(rect);
//add other scene node here
}
2.初始化视频图像获取相关数据
[cpp] view
plaincopy
<pre name="code" class="cpp">void InitVideoQuery(char *szVideoPath)
{
m_szVideoPath = szVideoPath;
m_pFileCamer=cvCreateFileCapture(szVideoPath );
m_pVideoImage=cvQueryFrame(m_pFileCamer);
m_pDrawImage=cvCreateImage(cvSize(1024,1024),8,3);
m_pTex=TextureManager::getSingleton().createManual("DynamicBg","General",
TEX_TYPE_2D,m_pDrawImage->width,m_pDrawImage->height,1,0,PF_A8B8G8R8,TU_WRITE_ONLY);</pre>}<br>
<br>
<pre></pre>
<pre></pre>
<p> </p>
<p>3.更新顶点缓存</p>
<pre class="cpp" name="code">void UpdateTextureImage()
{
m_pVideoImage=cvQueryFrame(m_pFileCamer);
if(m_pDrawImage==0)
{
cvReleaseCapture(&m_pFileCamer);
m_pFileCamer=cvCreateFileCapture(m_szVideoPath);
m_pVideoImage=cvQueryFrame(m_pFileCamer);
}
cvShowImage("img",m_pVideoImage);
cvResize(m_pVideoImage,m_pDrawImage);
HardwarePixelBufferSharedPtr buffer=m_pTex->getBuffer(0,0);
buffer->lock(HardwareBuffer::HBL_DISCARD);
const PixelBox &pb = buffer->getCurrentLock();
uint32 *data = static_cast<uint32*>(pb.data);
size_t height = pb.getHeight();
size_t width = pb.getWidth();
size_t pitch = pb.rowPitch; // Skip between rows of image
for(size_t y=0; y<m_pDrawImage->height; ++y)
{
unsigned char *pImgLine=(unsigned char *)(m_pDrawImage->imageData+y*m_pDrawImage->widthStep);
for(size_t x=0; x<m_pDrawImage->width; ++x)
{
// 0xRRGGBB -> fill the buffer with yellow pixels
unsigned char B=pImgLine[3*x];
unsigned char G=pImgLine[3*x+1];
unsigned char R=pImgLine[3*x+2];
uint32 pixel=(R<<16)+(G<<8)+(B);
data[pitch*y + x] =pixel ;
}
}
buffer->unlock();
}</pre>
<p><br>
</p>
<p> </p>
<p>值得一提的是,在更新顶点缓存的过程中,即lock到unlock之间,由于操作硬件缓存效率低,为了提高效率,应该尽量减少代码的操作量,可选的做法是在外面将数据打包好,然后在更新的时候直接memcpy</p>
<p><br>
</p>
<pre></pre>
相关文章推荐
- django 部署到Apache服务器上
- Apache Tomcat AJP 实现负载均衡
- Apache+JK+Tomcat 负载平衡配置
- 图像的反色Opencv
- CACTI从头到脚之监控硬盘IO及snmpd.conf 配置
- apache做负载均衡器 配置
- apache+jk+tomcat集群+session同步
- [贪心&&二分]uva714 Copying Books
- apache tomcat 6集群负载和session复制
- 基于nginx的tomcat负载均衡和集群(超简单)
- CentOS VNC
- Opencv中图像的缩放处理
- 图文解说:Nginx+tomcat配置集群负载均衡
- OpenGL入门示例1——黑色背景绘制绿色矩形
- Apache+Tomcat集群配置
- openssl相关介绍
- 在shell脚本里执行sudo 命令
- 堆栈,堆栈,堆和栈的区别
- hadoop自带例子wordcount的具体运行步骤
- 按位反转无符号整数问题bitoperate函数(转)