Need very precise timings to show a stimulus

[bn]

Hi Polyglot,

H264 is probably OK, but is not "lossless". The whole point of H264 is optimal compression. There are old codecs like motion jpeg that don't do temporal compression, just spatial. The downside is that you have a high data rate. But today computers should be fast enough for the throughput

One would have to experiment with formats if you run into problems with H264.

Can you recommend a codec that would achieve what you are saying for windows?

unfortunately I don't know anything about Windows Video.

Without an example Video it is very hard to give advice, there are too many variables. On the video side and LC side.

Kind regards
Bernd

[okk]

Hi,
have a look at this thread. http://forums.livecode.com/viewtopic.php?f=10&t=25644 Klaus mentioned there that it is sometimes good advice to let the player "breath", which means waiting a few milliseconds before/after setting the filename of a playerobject. At least the advice given by Klaus solved my problem with an occasional frozen startframe after setting the filename property of my player object.

Another issue could be that the playerobject has difficulties to play back at 60 fps. This might have many reasons, but I would try to experiment with different resolutions and compressions. As Bernd mentioned, you might want to use a codec that uses intraframe compression, as oppossed to interframe compression (such as H264 and many others). If you search for "intraframe vs. interframe compression" you will get plenty of info. All the Apple ProRes codecs use intraframe compression, but I am not sure if they are easily available for Windows.

I made a small test movie with a text plate at every 60th frame. It is in Apple ProRes (LT) compression at 720p resolution with 60 frames per second. It plays well in a playerobject in livecode on my 2012 macbook. http://speechkaraoke.org/files/720p6ofps.mov.zip It seems that none of the text frames are skipped.

Best
Oliver