is there a way to get a pcl pointcloud from std::istream instead of a filename

Question

I want to output a pcl point cloud from an istream (ply file read directly from server and can't be saved locally). Can anyone help if there is a way to achieve this?

I am familiar with pcl::io::loadPLYFile<pcl::PointXYZRGBA>(std::string fname, *cloud); but the function I am looking for is of the form xxxx(std::istream, *cloud); I tried looking at pcl's codebase in the github but couldn't get anywhere: :(

Answer 1

I don't think PCL has one function to do what you're asking. But looking at the .ply file format , I'd suggest you do something like following

1. Go through the file line by line
2. Once you find element vertex X , keep the number X
3. Once you find end_header , start reading vertex values (I'm guessing in the order of xyz r gba) from the next line to the next X th line
4. Assign the read values to a pointcloud you created