Real (average) fps is lower than labeled one

[kimiraikkonen]

Hi,

As i'm used to be curious investigating movie fps by pressing ALT+3 in Bsplayer, found out that though the movie (like WMV) is labeled and "seems" encoded at 30fps (looked with MediaInfo), real average fps doesn't exceed 22 or 20 fps. Though i cannot notice it visually, i believe it's right statistically.

Note: Some of other files encoded at 30fps are running fine, at 30 fps as average.

So, was there some loss of frames during encoding though file header labeled at 30fps?

Any idea about it?

Thanks!

[adicoto]

If your computing power is close to the minimum specifications, displayed framerate may lower beneath real framerate. And that depends on the file resolution (you can play fine 720x576 but can't play 1280x720).

[kimiraikkonen]

I though this but system resources are almost free, CPU load is under %30. So, i highly doubt that the frame loss happened during encoding/capturing the video? Can it be?

[adicoto]

Options -> preferences -> video -> rendering -> try not to skip frames - is it enabled ?

[kimiraikkonen]

Originally Posted by adicoto

Options -> preferences -> video -> rendering -> try not to skip frames - is it enabled ?

I do not have that option. Mine's version is a bit old and it seems that feature is new.

[BSPeter]

The option "Try not to drop frames" was introduced in version 2.21.950 of begin May 2007!!
To avoid misunderstandings and useless conversations (about issues which may possibly already have been covered in newer builds) posters should always mention version and build number! (This is equally valid for longstanding faithful and loyal supporters/users of BS.Player.)

[kimiraikkonen]

Originally Posted by BSPeter

The option "Try not to drop frames" was introduced in version 2.21.950 of begin May 2007!!
To avoid misunderstandings and useless conversations (about issues which may possibly already have been covered in newer builds) posters should always mention version and build number! (This is equally valid for longstanding faithful and loyal supporters/users of BS.Player.)

The problem in the thread which you closed: (Edit BSPeter: for what it's worth: thread reopened again)
CoreAVC drops frames though low cpu usage

...was completely different than the current thread. It was about a problem that results in frame drops, reported in ALT+3 video info page due to "internal renderer overlay(default)".

The current thread is about seeing real-time (average) framerate "lower" than expected, THOUGH no frame drops are reported in ALT+3. I mean, they're not the same. I beleive average frame rate, which is lower than expected, is because of capturing/encoding couldn't have managed to reach expected fps.

I noticed when i capture something from my Conexant TV capture device (AverTV) via Windows Media Encoder(you can try) 9, for some reason, average frame rate doesn't exceed 18~21 fps though expected is 30fps using sufficent bitrate setting with more than %50 of cpu is free.

Just wanted to get ideas about it, as i reproduced it.

[adicoto]

Can you upload a sample of such a file ? You didn't mention that there were files captured by you. I would like to test such a file.
On the other hand, none of the programs we talk about have the posibilty to take 100 % of CPU usage (in BSplayer's options you can set it's afinity but I believe you don't have such a new version). So, the OS doesn't allow to all aplications to have acces to full CPU usage, that's why you will notice that even if it does not use the CPU at 100%, some proceses will run slowly (such a capture device). If I am corect, to do a WMV capture and on-the-fly compresion for a resolution of 576x384@29,97 you will need at least a P4 @ 2GHz CPU (that excludes older Athlons, most of the Semprons and Celerons)