HD Video Playback: H.264 Blu-ray on the PC
by Derek Wilson on December 11, 2006 9:50 AM EST- Posted in
- GPUs
H.264 Encoded HD Content: A Good Thing
Almost anything can be done in a faster, more compact, or higher quality way. Sometimes there are tradeoffs to be made, and sometimes one way of doing things is just better than another. It has been quite some time since studios began distributing movies encoded in MPEG-2 stored on DVDs. Now that we have some new physical media entering the market, we will also see more efficient codecs enter the playing field as well.
H.264 is another name for a subset of MPEG-4 called MPEG-4 Part 10, or AVC (for Advanced Video Coding). This codec is a big step beyond MPEG-2 in terms of how heavily video of a given quality can be compressed. There are quite a few factors that make H.264 a better vehicle for video, but these are a little beyond the scope of this article. For now we will focus on the impact of H.264 and why it's a better option than MPEG-2.
The major benefit of H.264 over MPEG-2 is its small file size due to high compression. High resolution video can be stored in much less space. This is very useful because even though BDs can be 25 or 50 GB, high quality high resolution video is not small. The higher the compression we have, the higher the quality of video that will fill up a disk. Alternately, with high compression we also have extra room for the all important bonus features and extra content that we expect with any good DVD today.
Higher image quality is also inherent in H.264 due to some of the improved features of the codec. Variable block size motion compensation, better handling of interlaced video, in-loop deblocking, and better subpixel accuracy all contribute to a better overall image quality. Alternately, studios can use the image quality advantages to lower bitrate even more, as compression artifacts don't show up as readily.
With all these advantages, there is one downside to H.264: decoding the video takes much more work than with MPEG-2. High powered, dedicated H.264 decoding hardware is required in standalone BD and HDDVD players, as a generic processor just isn't enough to handle the work load. This is understandable as we have to make a tradeoff between file size/bitrate and the amount of work a CPU needs to do to reproduce the video, and H.264 produces very small files.
The large file size vs. heavy compression issue is actually fairly intuitive. Imagine completely uncompressed video where every pixel of every frame is stored in memory. The only thing we need to do to display the video is to send the data to the TV. This requires almost no processing but very high file size and bandwidth from the storage media. As a reference point, uncompressed 24-bit 1080p content at 24fps (the standard frame rate for movies) would require a whopping 1.19 Gbps of bandwidth and a 90 minute movie would need about 750GB of storage. Obviously, some form of compression is absolutely required.
When storing less data through compression, the CPU must do work to fill in the blanks before sending the video out to a display. With our previous Blu-ray test movie Click (which used MPEG-2), we saw bitrates of 50-60 Mbps throughout our test (representing somewhere between a 20:1 and 24:1 compression rate). Moving to X-Men: The Last Stand, most of our test is at about 20 Mbps, though we do see a very short spike that hits over 40 Mbps (somewhere around a 60:1 compression rate). We would need to compare the same section of one movie encoded in both MPEG-2 and H.264 in order to speak directly to the differences between the two, but for now we will generally see at least half the bitrate with H.264 that we get with MPEG-2. We also see a much lower CPU utilization with MPEG-2 because it doesn't compress the video as much as H.264.
If we focus on our high compression codec, we'll see that higher bitrates with H.264 mean more work for the CPU. When complex scenes occur, more data is required to generate a proper image. The CPU still needs to process all this data in the same way it would with a less complex scene, and we end up seeing higher processor utilization.
The encoding process takes more work as well, and we've been told that this is part of the reason we haven't seen many H.264 BD movies before now. When getting a movie ready for sale, studios will encode it many times and have people to view every frame of video and make sure nothing needs to be cleaned up. Every time a problem is found, the entire movie must be encoded again. It takes significantly more time to do this with H.264 than with MPEG-2. Fortunately, it seems that studios are making the sacrifices they need to make in order to bring a better experience to the end user.
To sum up, while MPEG-2 is relatively easy to decode, H.264 enables smaller files with better image quality. On the down side, the time it takes to encode a movie using H.264 is much higher than required for MPEG-2, and the processing power needed to decode H.264 without dropping frames can be very large. Without GPU acceleration, not even an Intel Core 2 Duo E6600 can play X-Men: The Last Stand without dropping frames.
Before we get to the test, we'll leave you with a short list of H.264 Blu-ray titles. While we don't have the bitrate information for all of these, we chose X-Men: The Last Stand because it listed 18 Mbps video (higher than some of the others) and has some fairly complex special effects.
Blu-ray H.264 Movies:
Behind Enemy Lines
The League of Extraordinary Gentlemen
X-Men: The Last Stand
Speed
Glory Road
Gone in 60 Seconds
Eight Below
The Great Raid
Almost anything can be done in a faster, more compact, or higher quality way. Sometimes there are tradeoffs to be made, and sometimes one way of doing things is just better than another. It has been quite some time since studios began distributing movies encoded in MPEG-2 stored on DVDs. Now that we have some new physical media entering the market, we will also see more efficient codecs enter the playing field as well.
H.264 is another name for a subset of MPEG-4 called MPEG-4 Part 10, or AVC (for Advanced Video Coding). This codec is a big step beyond MPEG-2 in terms of how heavily video of a given quality can be compressed. There are quite a few factors that make H.264 a better vehicle for video, but these are a little beyond the scope of this article. For now we will focus on the impact of H.264 and why it's a better option than MPEG-2.
The major benefit of H.264 over MPEG-2 is its small file size due to high compression. High resolution video can be stored in much less space. This is very useful because even though BDs can be 25 or 50 GB, high quality high resolution video is not small. The higher the compression we have, the higher the quality of video that will fill up a disk. Alternately, with high compression we also have extra room for the all important bonus features and extra content that we expect with any good DVD today.
Higher image quality is also inherent in H.264 due to some of the improved features of the codec. Variable block size motion compensation, better handling of interlaced video, in-loop deblocking, and better subpixel accuracy all contribute to a better overall image quality. Alternately, studios can use the image quality advantages to lower bitrate even more, as compression artifacts don't show up as readily.
With all these advantages, there is one downside to H.264: decoding the video takes much more work than with MPEG-2. High powered, dedicated H.264 decoding hardware is required in standalone BD and HDDVD players, as a generic processor just isn't enough to handle the work load. This is understandable as we have to make a tradeoff between file size/bitrate and the amount of work a CPU needs to do to reproduce the video, and H.264 produces very small files.
The large file size vs. heavy compression issue is actually fairly intuitive. Imagine completely uncompressed video where every pixel of every frame is stored in memory. The only thing we need to do to display the video is to send the data to the TV. This requires almost no processing but very high file size and bandwidth from the storage media. As a reference point, uncompressed 24-bit 1080p content at 24fps (the standard frame rate for movies) would require a whopping 1.19 Gbps of bandwidth and a 90 minute movie would need about 750GB of storage. Obviously, some form of compression is absolutely required.
When storing less data through compression, the CPU must do work to fill in the blanks before sending the video out to a display. With our previous Blu-ray test movie Click (which used MPEG-2), we saw bitrates of 50-60 Mbps throughout our test (representing somewhere between a 20:1 and 24:1 compression rate). Moving to X-Men: The Last Stand, most of our test is at about 20 Mbps, though we do see a very short spike that hits over 40 Mbps (somewhere around a 60:1 compression rate). We would need to compare the same section of one movie encoded in both MPEG-2 and H.264 in order to speak directly to the differences between the two, but for now we will generally see at least half the bitrate with H.264 that we get with MPEG-2. We also see a much lower CPU utilization with MPEG-2 because it doesn't compress the video as much as H.264.
If we focus on our high compression codec, we'll see that higher bitrates with H.264 mean more work for the CPU. When complex scenes occur, more data is required to generate a proper image. The CPU still needs to process all this data in the same way it would with a less complex scene, and we end up seeing higher processor utilization.
The encoding process takes more work as well, and we've been told that this is part of the reason we haven't seen many H.264 BD movies before now. When getting a movie ready for sale, studios will encode it many times and have people to view every frame of video and make sure nothing needs to be cleaned up. Every time a problem is found, the entire movie must be encoded again. It takes significantly more time to do this with H.264 than with MPEG-2. Fortunately, it seems that studios are making the sacrifices they need to make in order to bring a better experience to the end user.
To sum up, while MPEG-2 is relatively easy to decode, H.264 enables smaller files with better image quality. On the down side, the time it takes to encode a movie using H.264 is much higher than required for MPEG-2, and the processing power needed to decode H.264 without dropping frames can be very large. Without GPU acceleration, not even an Intel Core 2 Duo E6600 can play X-Men: The Last Stand without dropping frames.
Before we get to the test, we'll leave you with a short list of H.264 Blu-ray titles. While we don't have the bitrate information for all of these, we chose X-Men: The Last Stand because it listed 18 Mbps video (higher than some of the others) and has some fairly complex special effects.
Blu-ray H.264 Movies:
Behind Enemy Lines
The League of Extraordinary Gentlemen
X-Men: The Last Stand
Speed
Glory Road
Gone in 60 Seconds
Eight Below
The Great Raid
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Chucko - Monday, December 11, 2006 - link
So is the output resolution via HDCP DVI really not able to output at high res? I heard a few rumors about when HDCP was enabled the output resolution of these cards was less than 1080p. Is there any true to this?harijan - Monday, December 11, 2006 - link
I guess that no integrated graphic solutions will be able to decode them without dropping frames?Tujan - Monday, December 11, 2006 - link
" Intel Core 2 Duo E6600 can play X-Men: The Last Stand without dropping frames. ""Thus we chose the Core 2 Duo X6800 for our tests."
"we haven't found a feature in PowerDVD or another utility that will allow us to count dropped frames"
"The second test we ran explores different CPUs performance with X-Men 3 decoding. We used NVIDIA's 8800 GTX and ATI's X1950 XTX in order to determine a best and worse case scenario for each processor. The following data isn't based on average CPU utilization, but on maximum CPU utilization. This will give us an indication of whether or not any frames have been dropped. If CPU utilization never hits 100%, we should always have smooth video. The analog to max CPU utilization in game testing is minimum framerate: both tell us the worst case scenario"
"All video cards that have an HDMI connection on them should support HDCP, but the story is different with DVI. Only recently have manufacturers started including the encryption keys required for HDCP. Licensing these keys costs hardware makers money, and the inclusion of HDCP functionality hasn't been seen as a good investment until recently (as Blu-ray and HDDVD players are finally available for the PC). While NVIDIA and ATI are both saying that most (if not all) of the cards available based on products released within the last few months will include the required hardware support, the final decision is still in the hands of the graphics card maker. "
"It is important to make it clear that HDCP graphics cards are only required to watch protected HD content over a digital connection. Until movie studios decide to enable the ICT (Image Constraint Token), HD movies will be watchable at full resolution over an analog connection. While analog video will work for many current users, it won't be a long term solution."
This here:
"Fortunately, it seems that studios are making the sacrifices they need to make in order to bring a better experience to the end user."<-lol
..so tell me. What kind of processor and video graphics processor does a blue-ray 'box have ?
Somehow I dont buy the analog,as a premise to the test results...yet still you are probably correct in its detail.
Seems the person on the computer made all the sacrifices here.Those are thousand dollar rigs.! 'With a Blue-ray player there ?
I would be happy with 30 gigs of MPEG2 in this matter.Maybe use a fresnel lense or something for the Display.Or put a opaque projector up in some way.
Desktop Resolution:1920x1080 - 32-bit @ 60Hz
Doesn't your lab got enough money for a High resolution HDTV wDVI connectors ?
Im not understanding all the fat in the fire here.Studios.
__________________
Saw your last comment there Mr.Wilson. Noticed that some .avis have higher data rate than others. Why should 'I pay (in dollars,and technology) for that kind of pony ?
DerekWilson - Tuesday, December 12, 2006 - link
you mis quoted me --**Not even an** Intel Core 2 Duo E6600 can play X-Men: The Last Stand without dropping frames.
Tujan - Thursday, December 14, 2006 - link
Thanks for reply.Good to see you are on top of things. Yeah I simply didn't include the first portion of the sentence in quoting you there.The article has so many baselines in it. For now I guess that Xmen BR disk is the trait holder of wich did a performance consideration criteria then. Venturing to say then,that all BR are not created alike. That is other BR disks will not have the same characteristics as 'would have necesitated a 6800 CPU.
That is something of a rig that costs 2 grand.To include as well the BR player itself. Now a BR shelf box,it does not have a X6800 CPU,nor Nvidia,or ATI high-end graphics chips.(speaking comparately). And a Monitor capable of doing the resolution will certainly do so using only that set of components.
So I think that perhaps it would be question enough to say that BR 'penalizes'a computer using it as an accessory.
I dont know if this is true. Still if it was necesary to have BR accesories as you had listed them,BR would have had to have had them listed in the BR patent itself.BR is a fully capable technology w/o the computer.
So frankly the penalty here 'must be the DRM involved.Since BR does that on-the-fly incryption.'I'll just speculate.
Look at the power consumption there ! True the Sony Notebook I showed does only 1080i(check it if Im wrong). But the graphics there will run on a freekin battery! AND the notebook (with Sony liscencing power no doubt)can be hooked up to the family television setup - maybe in HD.
Lets face it though.I dont see the reason so timid to conduct comparisions to HDTV sets.? A Dell 30" monitor ,or something such as this ? Run the comparisons with the HDMI out to them from these bottle cork (the notebook I showed) technologies.
As in the same light,if an HDTV can display 1080P with an OTA,you've got to suppose that the 'bus'in wich is being conductive to it may or may have nothing or something in common to what the computer is doing.True you may laugh as there is nothing such as an HD OTA 1080P,and I dont know if there is.
Yet HDMI,HDCP etc thats a really fancy chance I either spend performance per dollar where It does me some good,or waste away to consider whom and of what technology can be participated to no avail.
If the whole industry is waiting on a freaking HDMI cable.WTF is wrong with you people.
I get a light on the players you'll hear some more.Why the timidity to put the archetecture on the block for testing !!!.Computers and more. And I dont give a farts rott for what RIAA,or MPAA sais. They dont have that life to lead.
Renoir - Thursday, December 14, 2006 - link
Tujan, I don't mean to appear rude but I find your posts very hard to understand and from one of the posts above I'm not the only one. Am I right in thinking english isn't your first language? If so perhaps you could make your posts a bit simpler and more concise. Again I don't mean to cause offence as I think you may have some interesting points to make I just can't quite understand them.Tujan - Thursday, December 14, 2006 - link
There is several topics covered in each paragraph.Put a [ ] at end of each paragraph.The article said a lot more than just conduction to the BR. For the most part I am darn tee'd off because you just dont take and burn 700 watts to run a BR. Now I dont know what the specs.are for the on-the-shelf BR players. But as I explained they do not have any components of the computer,and they sure dont take up that much power to run using them. A screen simply does its stuff and that is it.The screen should be capable of doing exactly what the BR disk was mentioned to be in HD WITHOUT A GRAPHICS CARD !!!.
Now I dont know what the parameters for this descretion is. I know that Walmart has a 4$ HDMI cable. And that HDCP Graphics cards do not use HDMI.
Your last post consisted of differences between running Quad Core with the BR. Well you can do Dual-server Quad-Core with the same graphics but if the connection,and testing cannot be done with HD screens,there is not much to have been said about them.
Especially the detail in the power utilization with the CPUs.So where's the descreprency ?
I am happy with an HDMI and Battery power on a notebook attached to a HDTV screen. Just how happy remains to be accessed. By both the graphics card vendors,and the authors of these not so confounding computer articles.
P.S.If I could have edited out the last paragraph from the last post I would have done so.It does not lack its substance though,since there must be a penalty to run BR on the computer.BR does not need this type of technology to conduct a standard session- as could be seen if the testing would be done.Then we could reason the problem.
Tujan - Thursday, December 14, 2006 - link
BTW. I cannot figure out exactly the reason the tested BR player was not listed in the test setup.The brand name,and type. And wether it was using a Sata connection (wich it probably was). It should not be long before anyone should be able to conduct data transfer tests between different computer based players.I dont know if I can wait or not. Since still we are dealing with certain media.And criteria specific to it. As well as the performance of them. So without that,a computer capable BR player should be the least of considerations.
Plextors got a blue ray player. Yeah think so. The specs. of the drive should have been announced.
See I just dont get the confoundedness of the HDCP and kissy feel good about the light hollywood puts out.For me,i have other considerations beyond them for the space,and the conduction of the technology.
happy holidays.
johnsonx - Monday, December 11, 2006 - link
I had a lot less trouble following the article than I did that post. What?Tujan - Monday, December 11, 2006 - link
Has anybody done a comparison of the bandwidth difference between HDMI,and DVI ? Ive only seen a lowly 1600 (Saphire-ATI) with HDMI. Although behind the scenes there are others. Had no idea of HD-DVD,or Blue-Ray were such 'system eating bandwidth hogs.Either way.Its a knuckle sandwich for the studios.
Hope everybody runs out an grabs all the DVDs that can fit in a shopping cart.
So I guess the 'hi-def resolutions is a 'studio spec. too ?