Change publishing rate in source code

edit

I'm subscribing to /camera/depth/image topic, after some processing I want to publish it again but in different rate.

I'm already trying to do it using some code but I didn't succeed yet. (Publishing is working)

I found a very short answer that I'm trying to follow but not very clear enough. Here

EDIT - SOLUTION:

I found a solution in throttle package, but I don't get really exactly the rate I input which is g_period=msgs_per_sec in the package:

The rate I get is:

rostopic hz /depth_output 

average rate: 15.018
    min: 0.063s max: 0.069s std dev: 0.00187s window: 14

Here is it:

ros::Time g_last_time;
ros::Duration g_period;

g_period = ros::Duration(1.0/20); //msgs_per_sec

ros::Time now;
now = ros::Time::now();
if((now - g_last_time) > g_period)
 {
   depth_pub_.publish(depth_msg.toImageMsg());
   g_last_time = now;
 }