[Eug Wanker]

http://www.internetnews.com/infra/article.php/3366831

So given that it takes a dual G5 to decode HD content, is such an encode gonna take just about forever? I also wonder with the advent of H.264 if we're gonna start seeing an H.264 HD DVD format showing up, using current generation dual layer DVDs.

BTW, how processor-intensive is it encode H.264 at say 320x240 to get uber-small file sizes, compared to say MPEG-2?

[f1000]

Originally posted by Eug Wanker:
So given that it takes a dual G5 to decode HD content, is such an encode gonna take just about forever?

Try using VLC to play back some of the sample HD clips that I posted in the following thread: http://forums.macnn.com/showthread.p...readid=213266.

On my 1 GHz 12” PowerBook, playback is fairly smooth.

[Eug Wanker]

Originally posted by f1000:
Try using VLC to play back some of the sample HD clips that I posted in the following thread: http://forums.macnn.com/showthread.p...readid=213266.

On my 1 GHz 12” PowerBook, playback is fairly smooth.

Interesting, but that's not H.264.

[f1000]

You’re right; I was just trying to give you hope that H.264 might not need a supercomputer to run smoothly.

[hmurchison2001]

http://www.videosoftinc.com/performance.html

AVC looks great but the upfront costs are daunting. Assuming MPEG2 is 1x AVC encoding is = 8x Decode 4x. I'm sure that's for HD quality though. In fact I read that there are encoding solutions for AVC SD which are realtime.

[Eug Wanker]

Originally posted by hmurchison2001:
http://www.videosoftinc.com/performance.html

AVC looks great but the upfront costs are daunting. Assuming MPEG2 is 1x AVC encoding is = 8x Decode 4x. I'm sure that's for HD quality though. In fact I read that there are encoding solutions for AVC SD which are realtime.

Hmmm... Interesting table... esp. this part:

P4 3 GHz does decoding 720x480 at 2 Kbps at 50 fps.

Interesting because Apple at NAB demonstrated the G5 dual at HD 1920x1080 at 8 kbps for smooth playback.

It does look like the encode is more than just twice the horsepower requirements of decode though. That same P4 does the 720x480 2 Kbps encode at 6 fps for best quality and 15 fps for good quality.

[hmurchison2001]

Yes encode is gonna be a bear. Here's hoping xgrid support comes to compressor. I could definitely see the need for throwing some cycles at AVC encoding if time important.

I think we've going to see large broadcasters stick with MPEG2 TS for broadcoast but the smaller and more nimble broadcasters will take the bandwidth advantage and run with it. Once AVC is piped through a HD-DVD recorder would have the same benefit of Blu Ray, recording straight digital data.

Also of interest are the extensions coming. Seach Google for "h.264 Professional Extension" and you'll get linked to some documents that show they plan to graft on support for 4:4:4 12bit color space and 4:2:2 8bit. No need to have it yet unless you're fond of spending 6 figures on a HD camera.

I'd love to see how AVC scales. I guess we'll know if QT7 has native support.

[f1000]

Originally posted by Eug Wanker:
P4 3 GHz does decoding 720x480 at 2 Kbps at 50 fps.

I think that's 2 Mbps (2000 kbps), not 2 kbps.

According to my calculations, 1080i .tp files play back at about 18 Mbps.

If Apple's implementation of H.264 really can compress 18 Mbps to 8 kbps, I'm impressed!

[Eug Wanker]

Originally posted by f1000:
I think that's 2 Mbps (2000 kbps), not 2 kbps.

According to my calculations, 1080i .tp files play back at about 18 Mbps.

If Apple's implementation of H.264 really can compress 18 Mbps to 8 kbps, I'm impressed!

Yeah, Oops. 2 kbps is barely more than a CD. I meant 2 Mbps (and 8 Mbps, about high quality DVD bitrates).

[bmedina]

Originally posted by Eug Wanker:
Yeah, Oops. 2 kbps is barely more than a CD.

Actually CD audio is 1.4Mbps. 2kbps is almost nothing.

[Toyin]

Originally posted by f1000:
Try using VLC to play back some of the sample HD clips that I posted in the following thread: http://forums.macnn.com/showthread.p...readid=213266.

On my 1 GHz 12” PowerBook, playback is fairly smooth.

That is friggin amazing ! Quite stunning on my 1.5ghz 15" PB. Some motion artifacts but so much cleaner than DVD. I can't wait to see HD DVDs in the future.

[mitchell_pgh]

Originally posted by Toyin:
That is friggin amazing ! Quite stunning on my 1.5ghz 15" PB. Some motion artifacts but so much cleaner than DVD. I can't wait to see HD DVDs in the future.

After seeing my friends HD TV setup, it actually sucked going back to DVDs on the screen. HD is so much clearer, but you don't notice it until you see it.

He now calls my rig "Low Def"

[Toyin]

Originally posted by mitchell_pgh:
After seeing my friends HD TV setup, it actually sucked going back to DVDs on the screen. HD is so much clearer, but you don't notice it until you see it.

He now calls my rig "Low Def"

I've got HDTV in my house and it is jarring going back to regular TV, but I think watching HiDef up close on the 15" LCD monitor is something else.

[f1000]

Originally posted by Toyin:
I've got HDTV in my house and it is jarring going back to regular TV, but I think watching HiDef up close on the 15" LCD monitor is something else.

Watching HD on a 17" widescreen isn't too shabby, either.

I do wish Apple would hurry up and put out an optimized player for these files.

[MaxPower2k3]

Originally posted by hmurchison2001:
I think we've going to see large broadcasters stick with MPEG2 TS for broadcoast but the smaller and more nimble broadcasters will take the bandwidth advantage and run with it. Once AVC is piped through a HD-DVD recorder would have the same benefit of Blu Ray, recording straight digital data.

FYI, they finalized the HD-DVD spec, and they're using the less-expensive (but also less storage) NEC/Toshiba technology, rather than Sony's BluRay disks. These store 15gb per layer (so 30GB on a dual-layer disk) as opposed to 57GB on a BluRay disk. The compression scheme has not yet been finalized, but H.264 and Microsoft's WM9 codec are both still in the running, along with a third that i'm not remembering now.


This is all from memory, but i know they didn't go with BluRay.


f1000 is correct, HD broadcasts using MPEG2 compression are 17-18mbps, meaning that a 2-hour clip is approximately 17 gigabytes. Using Microsoft's WMV-HD codec (or even DIVX, although it may not be quite as high-quality, since it's not designed for hi-def) you can compress it down enough to fit on a regular dual-layer DVD. With the new HD-DVD spec, they'll be able to fit approximately 3.5 hours of MPEG2-compressed HD onto a disk, or much more if they use a better compression scheme (which they will if they go with H.264 or WMV).

So, here's to hoping that they go with H.264 instead of the Microsoft codec.

[hmurchison2001]

Here's what I think happens.

HD-DVD is going to require 3 mandatory codecs. Here's what I believe is the order of preference.

AVC(h.264)- Open format and very efficient.

VC-9(WM9)- low cost licensing, very efficient. Negative-proprietary

MPEG2- Ubiquitious. Plenty of Encoder/Decoders. Negative- bitrate.

Blu Ray- Hoping they add AVC support which would give phenomenal time in recording.Excelent potential in computer applications. Negative- costs...existing fabrication plants for DVD cannot be used.

This battle is going to be very ugly unless there is some sort of compromise. Unfortunately I don't see a compromise coming. Sony realizes it needs to have a winner after failing in other recently edeavours. Toshiba and NEC are looking to reap the rewards that they missed out on in DVD.

I have no idea what company Apple will support. They will support AVC of HD-DVD but the have close enough relations with many of the members of the Blu Ray group.

[Eug Wanker]

Originally posted by bmedina:
Actually CD audio is 1.4Mbps. 2kbps is almost nothing.

Arrrggghh. Did it again. 2 Mbps.

[MaxPower2k3]

True, even though BluRay didn't make it as the official HD-DVD standard, it will probably still be used in other applications. It will be hurt, however, because owners of BluRay players will probably be limited to those people who have a use for creating them, whereas players of the new standard HD-DVD disks will eventually become a household item like current DVD players.

[f1000]

Originally posted by MaxPower2k3:
Using Microsoft's WMV-HD codec (or even DIVX, although it may not be quite as high-quality, since it's not designed for hi-def) you can compress it down enough to fit on a regular dual-layer DVD.

720p clips compressed using Microsoft’s WMV-9 format play back at 1.0 fps (yes, I actually counted the frames) on my 1 GHz G4 PowerBook (http://www.wmvhd.com). In my opinion, it's more economical to buy a big hard drive and store clips in a less processing power intensive format, such as MPEG-2, than it is to upgrade to a dual G5.

Besides, a 2-hour 720p MPEG-2 compressed movie only requires ~16 GB of storage space. Why settle for 1 fps at 6.3 Mbps, when you can have over 20 fps at 18 Mbps?

[Eug Wanker]

Originally posted by f1000:
720p clips compressed using Microsoft’s WMV-9 format play back at 1.0 fps (yes, I actually counted the frames) on my 1 GHz G4 PowerBook (http://www.wmvhd.com). In my opinion, it's more economical to buy a big hard drive and store clips in a less processing power intensive format, such as MPEG-2, than it is to upgrade to a dual G5.

Besides, a 2-hour 720p MPEG-2 compressed movie only requires ~16 GB of storage space. Why settle for 1 fps at 6.3 Mbps, when you can have over 20 fps at 18 Mbps?

To save space, to save bandwidth, and because current Windows hardware can decode WMV HD content, and current Mac hardware can decode H.264 HD content.

[MaxPower2k3]

plus i'm referring to HD-DVD disks here. assuming it becomes a standard, the same thing will happen as happened when DVDs first came out. At first, computers were barely fast enough to decode DVDs on their own, so hardware MPEG2 decoders emerged to do the job. Now, since only high-end PCs can decode 1080p WMVHD (720p is playable on a mid-level PC nowadays), i imagine hardware HD decoders will become more popular (whether it's to decode H.264 or WMVHD, whichever is the standard) until decoding HD-DVDs becomes trivial, just as it did with regular DVDs. this also applies to set-top boxes; making a dedicated processor to do one task is much more efficient and inexpensive than using a generic processor (such as is in a computer) and giving it a specific task. What takes, say, 30 operations with a PC's CPU may be done in a single operation with a dedicated decoder. So, even if it takes a $2500 PC to decode it, that is not indicative of the price of standalone decoders.

[Angus_D]

Originally posted by f1000:
720p clips compressed using Microsoft’s WMV-9 format play back at 1.0 fps (yes, I actually counted the frames) on my 1 GHz G4 PowerBook

Yeah, that's probably just because WMP for OS X is a total heap of doodoo.

[Eug Wanker]

So Apple leverages Altivec quite nicely for H.264 decoding. I wonder to what extent they can do the same for H.264 encoding.

I have heard rumblings out there that dual G5 Macs are amongst the fastest for H.264 encoding (amongst desktops) but I don't know how true that is.

[mitchell_pgh]

Originally posted by Eug Wanker:
So Apple leverages Altivec quite nicely for H.264 decoding. I wonder to what extent they can do the same for H.264 encoding.

I have heard rumblings out there that dual G5 Macs are amongst the fastest for H.264 encoding (amongst desktops) but I don't know how true that is.

I'm sure Altivec is key if they expect any speed...

[f1000]

I wonder why Apple won't include H.264 support until next year?

Maybe Apple's waiting until all of its computers have G5's?

[Horsepoo!!!]

Originally posted by Angus_D:
Yeah, that's probably just because WMP for OS X is a total heap of doodoo.

Hehe...it'll take a 25 GHz PowerBook to get HD movie files to play smoothly.

Maybe Apple can use this as a way to really get people onto the H.264 bandwagon.

"H.264 movies smooth as butter on a 1.6GHz G5. WMP9 HD would require a 20GHz G5."

Some know that WMP is just a shoddy job on Mac OS X. But Apple marketing can make the ad vague enough to sway people to the Mac side. So who cares if this doesn't apply to the PC side...it's true on Mac so you might as well use it to put a dent into WMP9's growth.

[Busemann]

Originally posted by f1000:
I wonder why Apple won't include H.264 support until next year?

Maybe Apple's waiting until all of its computers have G5's?

Or perhaps they just want to fine-tune & test the format before its being released...

[Horsepoo!!!]

There's some rumor on the AppleInsider forums (rumors=hopeful wishing) that QT7 will be coming with Tiger. I'm rather optimistic that QT will get a rewrite and show up aswell. H.264 will probably be released with QT7 on Tiger's launch. But who knows...