H.264 and mencoder help please and/or sage/ffmpeg

[bluenote]

For some reason whenever I use sage to create H.264 files, they end up being very CPU intensive -- even with coreavc, such that playing them back often results in pauses, and the little spinning arrow coming up in the middle of my video. Not *at all* like video files that I may download off the internet that use H.264. I've switched to mencoder recently to try and get this fixed, and it hasn't helped.

My question is twofold -- I am very obviously doing something that makes my encodes more cpu intensive to decode, does anyone have any ideas? I've now switched to mencoder (again) so if you have a favorite H.264 command line I'd love to see it (I'm doing EDL cutting at the same time btw, and Im interested in seeing how people are handling deinterlacing, as well..?)

Secondly, I find that mencoders files don't end up being very compatible. Occasionally I want to send/copy/whatever these files and on other platforms/decoders/whatever they dont end up being all that compatible. Does anyone have experience with that end? What can I do to make my mencoder files more standards friendly?

thanks for any help!

Cory

[Taddeusz]

Are these videos you're converting SD or HD? What are the specs on the system you're attempting playback? H.264 is much more CPU intensive on playback than MPEG2. Particularly for HD playback. My AMD X2 4200 could barely play 720p H.264. It could not play 1080p smoothly at all. This was with a Radeon X850XT. I now have a C2D 6550 and a Radeon 3870 and everything plays smooth as silk.

[bluenote]

Hi taddeus

I'm aware H.264 is cpu intensive, however, I get excellent results using the coreavc decoder and many files I find on the internet that are encoded H.264. When I make my own, however, my machine bogs on playback (in sage, particularily .. its better in WMP). I'm using crappy old hardware, but while it's working I prefer to solve the problem rather than throw CPU at it, which I find to be a never ending path.

thanks

Cory

[Taddeusz]

Originally Posted by cnovak

Hi taddeus

I'm aware H.264 is cpu intensive, however, I get excellent results using the coreavc decoder and many files I find on the internet that are encoded H.264. When I make my own, however, my machine bogs on playback (in sage, particularily .. its better in WMP). I'm using crappy old hardware, but while it's working I prefer to solve the problem rather than throw CPU at it, which I find to be a never ending path.

thanks

Cory

Certainly upgrading can be a never ending path if you make it so. But if you don't have a powerful enough CPU to do the job then you'll probably never be successful at playing back your files.

Now, you really didn't answer my questions so I can't really help you determine if you have a powerful enough computer or not. SD or HD, CPU, etc? What kind of video card do you have? Would it possibly have H.264 acceleration as that does make quite a difference.

[bluenote]

Sorry taddeus. This is SD content, and we're talking about a Celeron 1.7ghz.

Im not interested in solutions that end in "buy a new computer", because as I said, I *am* able to play back (and handily, too) H.264 encodes that I download.

thanks

Cory

[Taddeusz]

Originally Posted by cnovak

Sorry taddeus. This is SD content, and we're talking about a Celeron 1.7ghz.

Im not interested in solutions that end in "buy a new computer", because as I said, I *am* able to play back (and handily, too) H.264 encodes that I download.

thanks

Cory

That's all you had to say. You didn't have to be so defensive about it.

Now, this other content you mention. Is it actually H.264 (otherwise known as AVC) or is it DivX or XviD (usually shows up as MPEG4 in SageTV)? I ask because those formats require less CPU to decode. While both H.264 and DivX/XviD are considered MPEG4 they are quite different from one another. H.264 is far more advanced and as such does require more CPU.

What H.264 profile is being used to encode these videos? Sounds like AVC advanced profile might be used. Even main profile might be too much for your CPU. I personally don't use Sage's built-in transcoder. I use AutoMKV for those duties.

I really don't want to keep beating a dead horse but I could understand how a Celery 1.7Ghz CPU could not be able to keep up with even SD H.264. It is just that CPU intensive. Why not try MPEG4 and see if those play correctly?

Somehow though, I don't know that you're ever going to be successful until you bite the bullet and upgrade. That CPU is s-l-o-w. Particularly because it's a Celeron and it's a NetBurst processor. Trust me, I used to have one for a very short time.

If you don't want to hear it that's your business but thus far I've been the only person trying to help you.

[HawgGuy]

Originally Posted by cnovak

Sorry taddeus. This is SD content, and we're talking about a Celeron 1.7ghz.

Im not interested in solutions that end in "buy a new computer", because as I said, I *am* able to play back (and handily, too) H.264 encodes that I download.

thanks

Cory

Since you can play the files well outside of SageTV, have you tried increasing the Demux buffers in Sage?

HKEY_LOCAL_MACHINE\SOFTWARE\Frey Technologies\Common\DSFilters\MpegDeMux\NumBuffers

worth a shot. The default is 40, bump it to 80 and test playback. This is what I need to do to get r5000-hd streams to playback smoothly within SageTV.

[bluenote]

Taddeus: I'm comparing apples to apples to the best of my knowledge. That means GSPOT reports H.264/Mpeg 4 AVC for both my encode, and the downloaded encode. The main difference I see is that my encode is slightly higher bitrate (~260 kbs vs ~400). To really break it down, playing my encodes run approximately 20% higher cpu usage (comparing apples to apples playing back in WMP) than the downloaded encodes (and, my encodes look worse into the bargain ... but that is at least partly due to my source). They also both play back using coreavc. So really, my question is more, how do I encode a less cpu-intensive file.

Hawgguy: thanks for the suggestion! I did try this out, and had some success, but I have to admit that I was pressed for time and so I made several changes at the same time that *did* in fact result in smooth playback in sage. (It seems at some point I went back to using sagetvplayer, because I get better picture quality with it than CoreAVC, and so re-enabling coreavc would be expected to help as well). I believe that reg change did make a difference in between to a much better level before moving to CoreAVC. Do you have a handle on what it is supposed to do? I wouldn't expect a key described as "MPEG" anything to have an effect on H.264 playback? Any idea if this affects dshow, or sagetvplayer, or neither?
For some reason I had to force dshow by using the "always use" properties setting to make CoreAVC apply, is there a better method for this, do you know?


I'm still very much interested in finding out how to make better H.264 encodes with mencoder. If I'm doing something esoteric without meaning to, like using (and Im really talking nonsense here, while I have put a lot of time into reading about encoding methods, I am still an extreme novice) pyramidal b-frames and don'tcha know everyone knows that using those takes more CPU.

Anyone using mencoder to encode H.264 with good results, I'd love to take a look at the command lines used just to see if there are any differences with what I'm doing.

thanks guys

Cory