Reducing frame drop

[Chris Wells]

There seem to be a fair number of us that have to push the limits of our computer hardware to get HDV output in realtime. We need a thread where we share techniques to enable better HDV playback. I personally can play 640X480 60fps on my Centrino 1.4/512MB/64MB Dedicated Video, but I'm a just shy of being able to play 720p. Originally, I was dropping 7-9 frames per second, now I'm down to dropping only about two.

Tricks I have found help on XP SP2:
Disable my wireless Internet so Antivirus can be turned off (helps a little)
Go into Administrative tools and disable unused services (helps a lot)
Copy files to the hard drive before playing (mine won't even play from SD)
A fresh reboot (kinda temporary, but it does help)
With demuxing, removing audio got me to full speed (1920s anyone?)
Cleaning the junk off my drive (apparently hard drive performance is best at approx 40% full)

Things that could have helped but didn't:
Disabling advanced display options, such as screen transitions and font smoothing
Drive maintenance (defrag and scandisk)
Alternate players (presently using WMP 6.4 due for fast start times)
Disabled file indexing

Things that helped on my old Win98 system:
Ctrl-Alt-Del, then end all but Explorer and Systray (note that if you have vital components in this list, your machine may reboot... just leave whatever shuts it down and move on to the next item.) Visible difference in frame count, but must be done after each reboot.

Hopefully this list helps some get those last few frames out. Don't forget to post the tweaks that you figure out too... I've still got a couple frames more to achieve.

[Calin Brabandt]

Originally Posted by Chris Wells

I personally can play 640X480 60fps on my Centrino 1.4/512MB/64MB Dedicated Video, but I'm a just shy of being able to play 720p. Originally, I was dropping 7-9 frames per second, now I'm down to dropping only about two.

I haven't tried HD1 file playback on a Centrino 1.4 but my gut feel is that perfect playback should be possible. The most important thing you can do is to get a Directshow media player that provides control and flexibility. I use Media Player Classic (MPC), but other enthusiasts use Zoom Player, BSPlayer, or maybe Radlight or MyTheatre. They all provide user level control of the DirectShow Filter (DSF) "graph." Graphedit is also a helpful utility for testing filter graphs and is available in the MS Software Develper Kit (SDK), or just google for a download. VLC is not a DirectShow player; it is standalone. It works well for streams and has many nice features but, in my experience, it uses much more CPU for playback on a Windows machine than a good DSF.

The first thing you'll want to do is to set your player to use the overlay renderer. WMR 7 or WMR 9 may work, but you'll be sure to obtain lowest CPU usage from the overlay setting. (WMR 7 can use the overlay too, but set it to "overlay" mode just to be sure.)

Next, start looking for mpeg4 advanced simple profile (ASP) decoders. I have many on my system and, when I get a chance, I'll try to find a combination that produces the lowest CPU usage on HD1 files. If there is a DxVA (DirectX video acceleration) for your video card, that will probably be best. Unfortunately, DxVA is more often used for mpeg2 decoding than mpeg4. See this post for more info:

http://forum.doom9.org/showthread.ph...8&page=9&pp=25

The doom9 forums are the best place to learn about codecs. Please lurk awhile before posting to get a feel for the content. The doom9 forums are full of developers with low tolerance for newbish questions. Like any forum, use the search function.

Some mpeg4 ASP DSF decoders, in no particular order:

DivX
XVID
3ivx (thriv-ex)
Elcard/Moonlight
ffdshow
Dicas Mpegable
Microsoft
ATI AVIVO

I've only tried DivX, XVID, and ffdshow on HD1 content so far. They worked okay, but I didn't pay attention to CPU usage.

Not all decoder DSFs will connect to any given parser/splitter/demuxer. Some times a change in the container format may be necessary (mp4, avi, mkv, mov, etc.) For mp4 and avi, I use the Haali media splitter. MPC also has internal splitter.

Cal - DivX Forums Moderator

[Chris Wells]

If anyone has additional tips, I'd greatly appreciate them. The assorted players and codecs didn't offer the boost I needed. I'm a little shocked, but I'll live with it. I just have to admire my camera a bit more... my pocket-sized cam has more encoding and decoding power than a Centrino 1.4Ghz with 512MB and a dedicated video card... says a lot for what Sanyo has achieved (I wonder if I should read into what it says about M$?).

I'll eventually get a new laptop, or a more efficient codec will be developed. In the meantime, I will be working in the 60fps 640X mode. The resolution is lower, but with the higher frame rate and matched data rate, the video is still exceptional. Those of you that want good video and aren't concerned about 720p yet might try this option as a temporary solution to computer replacement. It looks a lot better than the choppy video, and it beats re-encoding if you aren't archiving the videos. It also seems to produce better quality high-motion shots.

[Calin Brabandt]

Originally Posted by Chris Wells

If anyone has additional tips, I'd greatly appreciate them. The assorted players and codecs didn't offer the boost I needed. I'm a little shocked, but I'll live with it.

Hmmm. I have a 1.8GHz Centrino T42 at work. I'll see how it does. If I can find a combo of DSFs and settings with enough margin to perhaps enable your 1.4GHz, I'll let you know, Chris. Sorry to hear nothing's working so far.

[Chris Taylor]

I just tried it on my 1.7ghz celery with 256mb of ram and it worked flawlessly. This video really does not take THAT much power to play back :-) I bet my zodiac could play it if tcpmp did not have a hard coded limit of 1008x1008 video dimensions :-)

Hmmm never tried the 640x480 6mb video :-) will have to try that.

I will try it later on a 500mh PIII and see what happens.

Chris Taylor
http://www.nerys.com/

[Bo Lorentzen]

Its playing pretty flawless on my Fujitsu P5000 with centrino and half a gig of ram. strangely it drops a few frames in the first 2 seconds, but then its smooth from there.. fills the screen beautifully.

Nothing specially done to the laptop. it also pays nicely from a 7200rpm laCie firewire drive.


Bo

www.bophoto.com/panos

[Chris Wells]

Thanks Bo,

That's not too powerful a machine. I'm pretty excited to hear your results, because they confirm what others have been saying... there is hope.

Do you know what codecs you are using?

[Chris Taylor]

AHH now there in lies the problem. codecs are everything. My 2.8g p4 with a gig of DDR had trouble playing these with the wrong codecs installed. so yes its a huge difference.

I installed the xp codec pack divx xvid and quicktime and real alternatives.

Chris Taylor
http://www.nerys.com/

[Bo Lorentzen]

Chris,

Im really pretty much illeterate in this, tried to get it to play a few ways, the followed a link here in the forum and installed VLC media player... bingo.. it works as advertised.


Bo

www.bophoto.com/HDV

[Chris Wells]

VLC player does the trick. My CPU which was pinned at 100% now reports only 58-60% utilization with 720p. There are no more dropped frames and I'm happy! One change of the associations and I'm forgetting all about my frustration.

Thanks Bo, and everyone that helped me out!

Here's a link to the VLC download in case anyone else needs it.
http://www.videolan.org/vlc/

[Calin Brabandt]

Originally Posted by Chris Wells

VLC player does the trick. My CPU which was pinned at 100% now reports only 58-60% utilization with 720p. There are no more dropped frames and I'm happy! One change of the associations and I'm forgetting all about my frustration.

Thanks Bo, and everyone that helped me out!

Here's a link to the VLC download in case anyone else needs it.
http://www.videolan.org/vlc/

That's great news, Chris! VLC is a good player and it's particularly good for streams. It's not usually the lowest CPU player around, however and I tend to use DirectShow players on Windows but good enough is good enough and it must be more efficient than your previous decoders. VLC is probably my favorite all around player for Linux and OS X and it's one of the few players for Windows that doesn't use MS DirectShow. Does you computer have DirectX9 installed? Or at least DirectX8? I think I forgot to ask. Oh well, like I said, VLC doesn't need no stinkin'' DirectX!

I still haven't had time to measure the CPU usage of half dozen or so DirectShow decoders I have on my system so glad to hear you've found a solution.