I look for a predecoder

[Squall83]

Hello everyone!

I want to play h264-encoded video files with very high resolution etc. , but my CPU is way too slow. Because of this I am looking for a program that can encode and decode various video formats in order to predecode the whole file before playing it, because the video should play without problems if my player doesn't need to decode anything during playtime.

I searched the whole forum for "predecode" but didn't find anything. Sorry if this question was postet many times already, but I couldn't think of any other reasonable keywords to search for (just "decode" yielded too many results).

Greetings, Squall83

[Soopafresh]

CoreAVC is the best h264 decoder for low end CPUs. What kind of processor do you have?

14 Day Trial of CoreAVC at
http://www.coreavc.com/index.php?option=com_content&task=view&id=41&Itemid=59

[guns1inger]

Nice theory, wont work.

You have two options.

One : Get a faster computer or perhaps, upgrade your gfx card to one that supports playback of these file in hardware

Two : Re-encode them in a way that your current system can handle. This would mean reducing resolution and data requirements to something realistic for your system

Simple decoding these files first will produce much larger, uncompressed files that your system will still fail to playback simply because it can't keep up with the data rate required.

[Squall83]

Um, I have a mere 1,4GHZ Pentium mit 512MB RAM and 64MB graphics card and I already tried the CoreAVC decoder. It did a lot better than CCCP, but the video still wasn't fluent.

I heard that h264 ncoded files use a very complex algorithm that makes the files very small but needs a lot of CPU power (and thus time) to decode so if I decoded it beforehand it should go faster, right? I mean if my PC would be only too slow for the decoding algorithm but not too slow to handle the data rate (which is yet to be tested) it should work.

[guns1inger]

You don't win either way on such a slow machine. You either decode a smaller video, and get poor playback because you don't have the power to decode quickly enough, or you decode it to an uncompressed video which is very large and has very high data requirements, and get very poor playback because you can't push the data through fast enough. The reason the video is compressed is so you don't have to move as much data around. Uncompress it (decode it) first and you go back to lots of data to shift.

You need a faster machine or a msaller, simpler version of the video. That's it.

[Squall83]

Hm, ok. But maybe that trick will work on videos with a resolution of about 1200x800 so I still would like to try out a program that can decode videos of any format. Do you know any free programs?

[Kayembee]

You don't win either way on such a slow machine. You either decode a smaller video, and get poor playback because you don't have the power to decode quickly enough, or you decode it to an uncompressed video which is very large and has very high data requirements, and get very poor playback because you can't push the data through fast enough. The reason the video is compressed is so you don't have to move as much data around. Uncompress it (decode it) first and you go back to lots of data to shift.

You need a faster machine or a msaller, simpler version of the video. That's it.

I wonder if a compromise might work? Before it got retired, I distinctly
remember running some 720p clips on my 1 GHz Athlon. I no longer
recall what clips, but I'm guessing they were MPEG-2, or maybe DivX.
These would be easier on a slow CPU than h264, but still require only
a fraction of the thruput needed for uncompressed.

I suggest encoding the clips to MPEG-2 at the same resolution and
a generous bitrate, and see how it plays.

[Squall83]

Thanks, that might be a good idea, too. I think I'll try that out.

Now for the main question of the topic: Where can I get a (good and free) software to acutally DO this? I know there are lots of free converters out there but I'd like to try out unencoded videos, too, and the converters I found always want to reencode immediately.

[Kayembee]

Thanks, that might be a good idea, too. I think I'll try that out.

Now for the main question of the topic: Where can I get a (good and free) software to acutally DO this? I know there are lots of free converters out there but I'd like to try out unencoded videos, too, and the converters I found always want to reencode immediately.

AVIDemux or Mediacoder (both free) will work, and there are others.

[FulciLives]

HCenc will encode MPEG-2 at resolutions as high as 1080p and HCenc is freeware.

- John "FulciLives" Coleman

[PuzZLeR]

Squall83 - you just don't have the horsepower for H.264 (decoding and encoding). The best you can decode without hiccups is Baseline Profile with 0 B-frames, etc. Anything much more will require more CPU grunt. You would be better off with MPEG-2 and I agree that HCEnc is a high quality free MPEG-2 encoder.

If you're patient, another alternative to CoreAVC, or a new machine, may be something brand new from the DivX Team called "Project Rémoulade". It shows great promise for the future and we're all very excited about it at the DivX Community. It's an H.264 decoder that is invite-only for now and currently in beta. I'm not currently sure how it will do on a slower machine, but if this doesn't do it for you if/when it's released, pretty much nothing else will do.

[yoda313]

Are there any standalone units that can do h264 decoding? Are there bluray players or addins for a 360 or ps3 that can do h264? That may be a better alternative for the op. Assuming the op has that ability.

[PuzZLeR]

Are there any standalone units that can do h264 decoding? Are there bluray players or addins for a 360 or ps3 that can do h264? That may be a better alternative for the op. Assuming the op has that ability.

PopcornHour, KiSS DP-700, Ziova CS615 come to mind. AppleTV and iPod play a "tamer" version of H.264.

I would say the best bet to play HD, or SD, High Profile Level 4.1 H.264 on a standard platform, without relying on exotic machines or watering it down may be encoding for blu-ray units (or PS3). The HD spec is easy, but I'm currently working on putting together a guide for those interested in SD on BD with H.264.

[yoda313]

Thanks puzzler. I forgot about those kiss players. Those were one of the first with divx support weren't they?

[PuzZLeR]

Hi Yoda,

I have no clue which was the first DivX certified stand-alone, but it's been going on since 2003 or earlier. I can say that the KiSS DP-700 was "officially" the first H.264 stand-alone player.

PopcornHour and Ziova seem to be the hot items now, which also use the Sigma Designs chipset (8634/8635).

But there is little mentioned about the fact that blu-ray plays high quality H.264 beautifully when muxed into a BD structure or M2TS container. If you get the exact spec right it will play in all players and any other player that also supports up to High Profile Level 4.1.

The BD spec should be the common denominator of compatibility with High Profile Level 4.1 H.264 as MPEG-1/2 have become using the VCD/SVCD/DvD spec.

[vhelp]

Don't mind my budding in here, but..

Has anyone actually put together any standard type profiles for: ffmpeg; mencoder; x264_cli
for encoding to exact h264 standards ??

If there is something that is obtainable through an "include" type text file where you let any one
of these freeware encoders import the parameter text and let it encode to h264, I'd be curious to
know what those params are. I'm mainly curious to try a couple of encodes.

-vhelp 4685

[Squall83]

Thanks, Kayembee, FulciLives and PuzZler. I will try those.

One more question though:

Squall83 - you just don't have the horsepower for H.264 (decoding and encoding). The best you can decode without hiccups is Baseline Profile with 0 B-frames, etc. Anything much more will require more CPU grunt. You would be better off with MPEG-2 and I agree that HCEnc is a high quality free MPEG-2 encoder.

I don’t understand why I can’t decode H.264 with my PC. I always thought having a slower PC just meant that everything would take longer than with a fast one, so why is it impossible for me to decode and encode H.264?

[guns1inger]

Yes, you can decode and encode h.264. However, as you have found, you simply cannot decode it fast enough to play it back smoothly. As encoding takes far more grunt than decoding, it will be a long and slow process.

I suspect that PuzZLeR was taking the point of view that if you can decode video fast enough for it to be watchable, then for all intents and purposes, you really can't decode it.

[PuzZLeR]

I suspect that PuzZLeR was taking the point of view that if you can decode video fast enough for it to be watchable, then for all intents and purposes, you really can't decode it.

Thank you. I stand corrected. By definition - bumps, skips, stutters and hiccups are officially within the context of "decoding" (no sarcasm). I should have made the distinction between no decoding and bad decoding. But I guess to most in this forum the two would be equal enough.

Squall83, keep in mind, H.264 uses advanced features such as multiple reference frames, b-pyramids, macroblocks, etc. during playback. These features alone depend on extra processing since more than one frame needs to be addressed at a time in order for its high compression to work. The Baseline Profile doesn't include these attributes, which was why it was created - to ease decoding for slower machines and portables (such as iPod).

[Squall83]

Um, now I have to correct myself. I was referring to predecoding. ^^ I thought that you meant that a slow machine makes mistakes during the predecoding process.
I'll try to convert them to other formats and if that won't work I'll lower the resolution and store the original where I can't see it until I buy a new machine. :wink:
With my 1280p screen I don't need any higher resolutions than that anyway. Thanks for the help!

edit: Hm, there's something wrong with your smilies. Trying 2 in a row gives the result above.

[PuzZLeR]

Um, now I have to correct myself. I was referring to predecoding. ^^

You will still have problems with the high bitrates as Guns1inger pointed out. I know it sucks, but if you seriously want to work with H.264 at higher resolutions and profiles you would benefit with an investment in a new machine. H.264 in fact was made to be a future format and not for the current machines at the time of its establishment in 2003 with the understanding that the "reasonable" processing would get better over time. We are still, even today in the "reasonable" part of the timeline. I believe H.264 will hit prime time fully when machines are able to encode it at HD High Profile in real time. We are still years from that.

Hm, there's something wrong with your smilies. Trying 2 in a row gives the result above.

This site links key words, and has prioritized the ":wink:" to link to the Wink software instead of the smile. Too bad. I kinda liked the "wink".

[PuzZLeR]

Just thought of it.

I don't have a free solution, but something that is alot cheaper than a new PC if it works for you. Cyberlink PowerDvD is probably the best playback app and can handle almost anything you throw at it. Never tried it on a slower PC, but you can try it for free here.

[Squall83]

I think I'll wait a few more years before I buy a new machine. My 1,4 Pentium Laptop can still do most of the stuff I want him to do and if I don't want to watch H.264 without downsampling it, play the newest games or use highly professional Software for something, I don't have any problems. Most SW/games/videos runsmoothly on even older PCs, too.

I have PowerDVD, too. It was in the Software package I received with my PC. I can try it but I wouldn't understand why PowerDVD should be able to play H.264 on a machine which is too slow.

[PuzZLeR]

I have PowerDVD, too. It was in the Software package I received with my PC. I can try it but I wouldn't understand why PowerDVD should be able to play H.264 on a machine which is too slow.

Not sure if the free version may be as good as the bought version - don't quote me on that. "wink"

I personally downloaded the trial version of the product and found it very good. Even with my 2-core, I had improvements - it never stuttered once as where VLC, MPC, WMP would from time to time with High Profile H.264. This is why I believe it may perform much better for your machine too.

The only reason I didn't buy it is because it doesn't play blu-ray disc images from my hard drive (something to do with the movie companies, whatever), which was my interest in it, but maybe I may reconsider since it was truly very good.

It wouldn't hurt to try the product version in the link I gave you. I agree, other than the more demanding video, you probably won't need a fast machine for most stuff. But if the product version of PowerDvD does it for you in the meantime it could be worth it for just a few bucks to comfortably carry you over till you get your new machine a few years from now.

[Squall83]

ok, thank you, I will try everything I've learnt in here as soon as my diploma exams are over. ^^