We are adding support for Smooth Streaming to our H264 Streaming Module.. Next to supporting videos encoded by the Microsoft Expression Encoder (VC-1 multi bit rate) we are also adding support for H.264 encoded videos (H.264 multi bit rate) which can be encoded by open-source (X264) software.

Watch our demo of Smooth Streaming H.264!

For some reason, I needed a object factory. Well, that’s easy you might think: this subject is well understood and textbook material.

It turns out differently.

There are in fact several places where you can look: - Loki - Codeproject - Boost Sandbox

But these are all either too specialized or too generalized: nothing fitted quite what I needed: an object factory that creates objecst based on the types of the constructor parameters …

For example:

typedef ObjectFactory<base* (int, float), short> factory_t;

where base* (int, float) is the constructor signature, and short is the key (but you could use std::string just as easily).

The best solution was to be found on Gamedev

But this too needed a bit of attention: I wanted N constructor parameters, without having to specialize them by hand – as that would be silly.

So, with the help of Boost.Preprocessor I came up with the following.

The template is here

The template is specialized once for a constructor without arguments, and with the use of Boost.Preprocessor N times; well, between LIMIT_LOWER_BOUND and LIMIT_UPPER_BOUND – which you can adjust if you need more …

The above will allow for code like this unit-test

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struct base {};

struct node1 : public base
{
  node1(int) 
  { std::cout << "node1(int)" << std::endl; }
  
  node1(int, float) 
  { std::cout <<"node1(int, float)" << std::endl; }
};

void test_object_factory()
{
  std::wcout << L"object_factory_test: " << std::endl;
  
  typedef ObjectFactory<base* (int, float),
     char*> node1_factory_t;
  
  node1_factory_t nf;
  nf.Register<node1>("node1");

  base* n1 = nf.Create("node1", 2, 3.0);
  delete n1;

This would create an object with the (int, float) signature.

Isn’t this a nice and clean way of forking?

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def daemonize
  exit if fork                   # Parent exits, child continues.
  Process.setsid                 # Become session leader.
  exit if fork                   # Zap session leader. See [1].
  Dir.chdir "/"                  # Release old working directory.
  File.umask 0000                # Ensure sensible umask. Adjust as needed.
  STDIN.reopen "/dev/null"       # Free file descriptors and
  STDOUT.reopen "/dev/null", "a" # point them somewhere sensible.
  STDERR.reopen STDOUT           # STDOUT/ERR should better go to a logfile.
end

That is, it’s the same as in Steven’s Advanced Programming for the Unix Environment, but a lot less verbose. Then again, above is Ruby – Stevens is C.

Q: What happens when Google tries to match Disney videos to their pool of advertisers?

A:

Ah, 31 animals . Let’s see, there’s Alex, Marty, Melman, Gloria, Julien, Maurice, Moto Moto, ...

You can automatically deploy your own application to the iPhonedevice by using Capistrano.

Requirements: Capistrano (gem install capistrano) and ldid (install via Cydia).

Build your application for the ARM architecture:

  bjam --toolset=darwin macosx-version=iphone-2.0 architecture=arm release

Deploy the application to the iPhone:

  cap deploy

Your app is packaged (tar), copied (scp) to your iphone and SpringBoards is restarted. I use the following Capfile:

set :application_name, "LocateMe" 
set :iphone_ip, "192.168.1.4" 
set :user, "root" 
# password = alpine

desc "Package your iPhone application" 
task :package do
 %x[cd "~/Library/Application Support/iPhone Simulator/User/Applications/00000000-0000-0000-0000-000000000000" && \
    tar -czpvf #{application_name}.tar.gz #{application_name}.app && \
    scp #{application_name}.tar.gz #{user}@#{iphone_ip}:/Applications]
end

desc "Install the application on your iPhone" 
task :install, :hosts => "#{iphone_ip}" do
  run <<-CMD
    cd /Applications/;
    tar -xzpvf #{application_name}.tar.gz;
    rm #{application_name}.tar.gz;
    ldid -S /Applications/#{application_name}.app/#{application_name};
    killall SpringBoard;                  # OS 2.0
#   /Applications/BossPrefs.app/Respring; # OS 2.1
  CMD
end

desc "Package and install the application on your iPhone" 
task :deploy, :hosts => "#{iphone_ip}" do
  package
  install
end