I want to offer an alternative to the timecode struct, I had issues when I needed to roll timecode across the midnight hour: I solved it by adding code to the bad format error code, it was a quick (ugly) fix.

recently I was playing with extention methods and thought that it might be simpler to create timecode from the DateTime and Timespan classes in the CLR, in my case I am only interested in PAL 25fps so I created a couple of extention methods. I wondered if this would be a simpler approach? So here are the few lines of code which I worte to extend DateTime and Timespan, hopefully it may be of use to someone.

public static partial class DateTimeExtentions
{
public static string ToTimecodeString(this DateTime DateTime)
{
return GetTimeCodeAsString(DateTime.TimeOfDay);
}

public static string ToTimecodeString(this TimeSpan TimeSpan)
{
return GetTimeCodeAsString(TimeSpan);
}

private static string GetTimeCodeAsString(TimeSpan TimeOfDay)
{

long framecount = AbsoluteTimeToFrames(TimeOfDay.TotalSeconds);
int hours = Convert.ToInt32((framecount / 90000) % 24);
int minutes = Convert.ToInt32((framecount – (90000 * hours)) / 1500);
int seconds = Convert.ToInt32(((framecount – (1500 * minutes) – (90000 * hours)) / 25));
int frames = Convert.ToInt32(framecount – (25 * seconds) – (1500 * minutes) – (90000 * hours));

return FormatTimeCodeString(hours, minutes, seconds, frames);
}

private static string FormatTimeCodeString(int hours, int minutes, int seconds, int frames)
{
string framesSeparator = “:”;

return string.Format(“{0:D2}:{1:D2}:{2:D2}{4}{3:D2}”, hours, minutes, seconds, frames, framesSeparator);

}

private static long AbsoluteTimeToFrames(double totalSeconds)
{
return Convert.ToInt64(25 * totalSeconds);
}
}

Yes, still active. Just busy. Depending on where you picked the timecode.cs file up from that was definitely a known issue. I think it was fixed in the Microsoft Media Platform Editor code drops and if not I can try to post an updated version that I have. It was basically a rounding issue.

I am not sure this blog is still active, but I have implemented your suggestion with TimeCode.cs for subtitle editor purposes.

When using 29.97 it works great, but in 24fps i have sometimes 1-2 frame offset between the real frame and the calculated frame from TimeCode. (I have watermarked frame counter on the movie itself – so I can compare results).

Any idea what can cause this? can this be related to this comment here where the calculation takes time more than 1 frame???

Thanks!

For Input wmv file the ASF viewer shows:
1) Header Object
2) Data Object
3) Simple Index Object
4) Timecode Index Object

For Expression Encoder generated file wmv file show:
1) Header Object
2) Data Object
3) Simple Index Object

Don’t know if this helps

I was wondering if there is a way to add the timecode using expression encoder as was possible earlier with windows media encoder sdk as stated in

http://discussms.hosting.lsoft.com/SCRIPTS/WA-MSD.EXE?A2=ind0511b&L=wmtalk&P=2441

I will be grateful to any suggestions/pointers

Beyond that, the only other workaround that even remotely comes to mind is build a MediaStreamSource and handle all of the samples yourself, but that is a fair amount of work.