chrono

I'm using OpenCV to write a video file. For cv::VideoWriter to work correctly the call to the write() function has to happen exactly 30 times per second (for a 30fps video). I found this code which uses the boost library to achieve this. I want to to the same but using std::chrono in my program. This is my implementation: std::chrono::high_resolution_clock::time_point prev = std::chrono::high_resolution_clock::now(); std::chrono::high_resolution_clock::time_point current = prev; long long difference = std::chrono::duration_cast<std::chrono::microseconds>(current-prev).count(); while(recording)

Can chrono be used as a timer/counter in a bare-metal microcontroller (e.g. MSP432 running an RTOS)? Can the high_resolution_clock (and other APIs in chrono) be configured so that it increments based on the given microcontroller's actual timer tick/register? The Real-Time C++ book (section 16.5) seems to suggest this is possible, but I haven't found any examples of this being applied, especially within bare-metal microcontrollers. How could this be implemented? Would this be even recommended? If not, where can chrono aid in RTOS-based embedded software? I would create a clock that implements

I have a double containing seconds. I would like to convert this into a time_t . I can't find a standard function which accomplishes this. Do I have to fill out the time_t by hand? The type of std::time_t is unspecified. Although not defined, this is almost always an integral value holding the number of seconds (not counting leap seconds) since 00:00, Jan 1 1970 UTC, corresponding to POSIX time. So, just a safe casting between them could be fine. Also be carefull about portability (because it's type is not specified in the standard) and consider about the values than can not fit while casting

I'm creating a timeline UI control, and time on this timeline always starts at zero, like a stopwatch. I thought of using std::chrono::steady_clock to keep the start and end time on the scale, however, it feels wrong to have a clock-time here, like '10am march 2017' has nothing to do with the beginning of the scale. Should I/can I create a custom clock that starts time at '0'? Here is an example custom chrono clock that is based on steady_clock and counts time since the first time it is called (approximately): #include "chrono_io.h" #include <chrono> #include <iostream> struct MyClock { using

I have several questions about new <chrono> header in C++ 11. Using Windows 7, Visual Studio 2012. Looking at the example http://en.cppreference.com/w/cpp/chrono #include <iostream> #include <chrono> #include <ctime> int fibonacci(int n) { if (n < 3) return 1; return fibonacci(n-1) + fibonacci(n-2); } int main() { std::chrono::time_point<std::chrono::system_clock> start, end; start = std::chrono::system_clock::now(); int result = fibonacci(42); end = std::chrono::system_clock::now(); int elapsed_seconds = std::chrono::duration_cast<std::chrono::seconds> (end-start).count(); std::time_t end