H.264 on nothing but G5s

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ktwdallas

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I'm a little disappointed with the H.264 because in all the marketing hype, they seem to have neglected to mention that you basically need to run it on a desktop to get it to perform. The processing power is so high that iChat AV can't do video conferencing unless you're on a G5 or at least a dual G4 (a desktop either way).

After installing Tiger on my iBook 1Ghz G4, the sample trailers on Apple's website to show off H.264 run very choppy b/c the computer just can't keep up. This isn't going to be the killer codec everyone things it is if half the people out there don't have good enough machines to view it. Makes me wonder what the minimum proc speed on Windows will be when the Windows version of QT7 ships.

In the Tiger demo email that went out today (the pointer to the online Quicktime) had a segment on iChat AV and he makes some comment about he's traveling to Europe and can't wait to use the iChat video to conference. The impetus there seems to be he'd he taking a laptop, but that wouldn't happen since no laptop from Apple currently meets the specs. Making a comment about being able to "Travel to europe and video chat" certainly makes it sound like they're targetting laptop warriers.
 
ktwdallas said:
After installing Tiger on my iBook 1Ghz G4, the sample trailers on Apple's website to show off H.264 run very choppy b/c the computer just can't keep up.
Click to expand...


I just logged on here because I tried to watch the 1080 version of the Batman Begins trailer and the video is super choppy and was wondering if others were having the same problems. Guess I feel better that it's not just me, but kinda sucks that h.264 will only work on a handful of the product line.
 
Keep in mind, the requirement for G5 is only for h.264 rendered at HD resolutions. I tried on my 1.67 17" PB, and it isn't bad, tho not 30fps for most I suspect.
 
You only need a G5 to HOST iChat AV conferences. You only need a GHz+ G4 to participate (this comes straight from the mouth of the guy demoing it at the Apple Store yesterday, and I think Steve Jobs said the same thing during his keynotes) — so that includes all recent laptops.

HD H.264 seems to need dualies, or at least a powerful single G5. My 1.25GHz Mac mini can't handle full 1920 HD content. But that really shouldn't be a surprise. It can't handle 1920 MPEG4 content, either. In fact, I'd say H.264 actually performs better than MPEG4 at these resolutions.

HD is tough. Look at the Windows side: 1920 Windows Media requires a 3GHz+ P4!

Remember, this is the birth of HD. When DVDs came out, most computers didn't have the processing punch to decode them, either. Most that could relied on seperate decoder cards. Time will tell if such things will be used for H.264 in the future.
 
H.264 will scale down to 3G cell phones. You're only viewing HD video and since it's all decoded in software you need a fast CPU to do it.

Wait until H.264 decoding is implemented on graphics cards like they do for MPEG 2 decoding. That'll make it more of an option for HD on computers.

I'm not really sure why it needs such a high end computer to host iChat vid conferences though. The video is really not all that big in it. The host must be doing a lot of extra stuff to make the conference work. What it's doing, I do not know.
 
The 1280*x trailers work quite fine on my PB (and that REALLY ain't a G5). But H.264 isn't all about HD resolution. This will be a very fine codec for you on your iBook if your movies are encoded at, say, 720*x or 640*x.
 
the batman 1080p trailer works very nicely on my g5. (i'm not gloating, just saying. mine is a lowend powermac, so it's reasonable. i remember my first dvd drive on my pc - (a 266mhz pII) couldn't actually play dvds without being choppy.

it's strange - the graininess on the camera shows - to the point where i just want to see somethingt pixar et al to ge the full crispness of it (exported from the vector 3d models to 1080p)
 
OK, can someone verify that the iChat AV chats require at least one end of the chat to have a G5?

I currently do a reasonable number of video chats (one-to-one) with a friend, and we both only have 1GHz PowerBooks.

Is Tiger going to rule me out of chatting to them now?

Plus, does this new H.264 codec for video conferencing mean that AIM-iChat video conferences are no more?
 
theres a link there on some pages for the 1080 version, including batman.

interestingly, the Serenity link for 1080 actually gives you a 1920x863 (from memory.. not at home right now)
 
FYI--The HD h.264 examples do not play well at all on my ibook G4 800 MHZ 640 RAM. I kind of expected it to play a LITTLE bit better, but it's really unusable. After reading the reminders that MPEG-2 gave us the same problem a few years ago, I don't really mind so much. Also, all my production work is on the 2.7, so no biggy. It is, however, another clear example of Appple just "forgetting" to let everyone know that they con forget about h.264 HD on anything but newer boxes. But, as always, Apple is here to sell boxes and h.264 will help do that.

Did anyone see the Tiger trailer on the 30" cinnies at an Apple store? I presume it was an h.264 file. I dug around and found the file that was playing it (not QT player) and it was a custom ".app" file Apple must have made. I couldn't find way to tell what the source movie file was. Presuming it was h.264, it was pretty much a perfect file. I couldn't find an artifact in it. You'd think you'd see some kind of artifact on a 30", but the thing was stellar. It will be a joy seeing the next batch of movies go h.264. I find (most) mpeg-2 almost unwatchable on an HD screen.

As for h.264 and iChat, since h.264 is scalable, I would think they would be using a much less demanding set of rates and quality settings during compression. I have no evidence for this, just speculation. As mentioned, h.264 scales all the way down to cell phones, so any of our Macs can use it, it's just a matter of at what quality and size and frame rates can we use it. It's not like iChat is pumping out HD quality imaging. I've got to believe that iChat AV will run fine on any G4 or better, laptops included. Also, there's a bandwitdh limit in iChat's prefs. Might this simply compress h.264 on the fly to different settings? Just a guess. I grabbed an iSight the other day, but haven't had a chance to use it in an iChat session.
 
texanpenguin said:
OK, can someone verify that the iChat AV chats require at least one end of the chat to have a G5?

I currently do a reasonable number of video chats (one-to-one) with a friend, and we both only have 1GHz PowerBooks.

Is Tiger going to rule me out of chatting to them now?

Plus, does this new H.264 codec for video conferencing mean that AIM-iChat video conferences are no more?
Click to expand...

Hi texanpenguin - don't worry!

1 to 1 video chats require 600MHz G3, any G4 or any G5 - whether initiating the chat or participating.

To initiate a multiple person chat you need a Dual 1GHz G4 or any G5

To participate in multiple chat you need 1GHz G4, dual 800 MHz G4 or any G5, so you're good to go!

All chats require 100 Kbps up/down except the person initiating a multiple person chat - they need 384 Kbps up/down.

The attached is from Apple's website...

Happy chatting!

;)
 

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I had my first 1:1 ichat video session (isight) yesterday on the new Tiger. The video transmission from my 12" Powerbook to the other end was extremly choppy. I never had that problem on Panther. As a matter of fact video session were very smooth and extremly efficient on Panther. We tried several times to reconnect but it never got any better. Any hints how to get back to the prior performance?
 
I've just encoded my first DVD(Sky Captain and the World of Tomorrow) using h.264. The results are very impressive. I've managed to squeeze the film into 700 MB and it looks very much better than DivX or XviD. None of the artifacts usually associated with DivX (blockiness, etc) are visible. The video even resizes really well.

On my Powerbook G4 12", it takes about 50% CPU power to play the movie, which isn't too bad. Granted, it wasn't encoded at HD resolution, but at 480x272. Even so it resizes really well and you can play it full screen with no visible deterioration in quality.

The only downside about this codec is it takes nearly forever to encode stuff. With DivX, it would take about twice the time of the film to encode. h.264 encodes at about 5 fps on my machine, and it takes nearly 6 times the original film time to encode. Perhaps that's because I'm using Handbrake's encoder, instead of QuickTime? Anyone know how I'd rip DVDs using Quicktime's h.264 encoder?
 
With comments above on the CPU requirements for iChat using this codec, it doesn't surprise me your CPU was so tapped, Viro. It sounds like a minor miracle that anyone is able to encode one live stream and decode another with h.264. It certainly sounds like they've throttled the settings back so far as to make it unwatchable. Pity.

I wouldn't expect too much in the way of improvement in encoding times from Quicktime. I found their encoding products in the past were significantly slower and more restrictive than other third-party encoders. I've always hated Quicktime for the complete lack of flexibility they offer the public and the limited flexibility they grant their customers. For example, full-screen-black mode is, I think, a basic requirement of a video product and Quicktime seems to think it is only an enhanced feature. Whatever. For players, I'll stick to VLC, thanks.

I'd bide your time and stick with DivX, unless you can spare the computer time. If this codec does take off for the general public, rather than being used only by broadcasters, it will probably come from some small company you've never heard of. And as always, it will come as a complete surprise to the Quicktime team.
 
hmm. i can usually transcode MPEG2 (from DVDs) to high-quality 3ivx MPEG4s a bit faster than real-time. i might have to try transcoding to H.264, and encoding some DV...
 
50% CPU usage isn't too bad. I can still run loads of applications in the background, or place my video on the secondary monitor and carry on working. I think the encoding time is worth it for the quality. Very similar to DVD still even at 980 kbits/sec at 480x272. And unlike DivX, you can more than double the size of the viewing window and you don't get any visible deterioration in quality or increase in CPU usage.

But for crying out loud.... 5 fps encoding?!? That takes way way way too long. I don't think it'll ever get much faster. :(
 
of course it'll get faster. when you buy a newer computer. when QT7 is more optimised. when CoreVideo is more optimised. or. you may get 15 FPS when you sell your soul to satan to get a Quad-[Dual-core]-Processor G6 XStation performance workstation with 4 RAIDed 800Gb SATA IV 15000RPM disks (128Mb Buffer each), 16Gb Quad-Channel DDR5 RAM (the base config) dual 10Gb Ethernet + 10Gb Fiber, and Firewire 3200
 
that too. but we're talking about ENCODING don't forget, not DECODING. the GPU will help decode, so you can watch it, but I doubt it will help with encoding. a faster GPU doesn't help with DVD MPEG2 encoding, does it?? (that is not a rhetorical question)
 
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