Processing power for H.264... YoutubeHD vs Vimeo vs ???

[The111]

I've posted recently about the web video gallery I'm creating (example here):

http://www.matthoover.com/gallery/skydiving-videos/Z-Flock_4.0-HD.html

I'm using H.264 to compress the video and had heard that it takes a lot of processing power and wanted to make sure I wouldn't be screwing over any potential viewers with low power processors. Yesterday I went to the link above with a friend's quad core laptop (that he said needs to be defragged) and viewing the video was extremely choppy (not a connection issue, was fully loaded). He said he was pretty sure it was his laptop running poorly in general (needing defrag and cleared HDD space), not the processor. So then I went to view some YoutubeHD videos on his computer and they played fine, no chop! So at that point I was worried and checked some Vimeo videos on his laptop and they DID chop (like mine) which made me feel better.

Basically I know YoutubeHD and Vimeo are sort of the "standards" right now for the common household connection/PC being able to view streaming HD on the web, so I want to have about the same requirements as they do. I'd heard Vimeo used VP6 and YoutubeHD used H.264 which makes no sense since I use H.264, and for my friend my videos and Vimeo DID chop, but YoutubeHD didn't.

Any thoughts?

[Baldrick]

What resolution and bitrate are you using? Higher resolution and bitrate requires faster cpuuuuuuuuuu.

[The111]

1280x720, 2000kbps. This is the same as YoutubeHD as far as I can tell.

[nitro1973]

they should stop calling it HD. quality is poor as hell. those seettings you wrote shouldnt take much cpu power and should run smoothly on old cpus. but the quality... my god

[The111]

they should stop calling it HD. quality is poor as hell. those seettings you wrote shouldnt take much cpu power and should run smoothly on old cpus. but the quality... my god

I'm not sure if you're talking about my videos specifically, or just in general, the 720p compressed HD of the popular sharing sites these days.

Bottom line, no it doesn't look as good as uncompressed 1080p HD. However, I wouldn't call it "poor"... it looks A LOT better than the TV set I was watching analog 480i cable on just 5 years ago. For a low bitrate internet-streamed media... I think this is very impressive, and it is technically HD as far as I understand the definition.

[poisondeathray]

Certain settings are more cpu intensive for decoding than others; e.g. the high reference frames might make or break smooth playback on older cpus, but the same video @720p, same bitrate but lower quality settings might be able to play smoother. e.g. HD Apple movie trailers @ 1080p can even play smooth on some older single core CPUs because of lower settings (AVC Main, 2-3 ref frames, etc....). That is the price you pay for better quality/compression, and that will mean some people will get jerky playback. Besides the bitrate & resolution, CABAC and deblocking are also CPU resource hogs.

[nitro1973]

I'm not sure if you're talking about my videos specifically, or just in general, the 720p compressed HD of the popular sharing sites these days.

Bottom line, no it doesn't look as good as uncompressed 1080p HD. However, I wouldn't call it "poor"... it looks A LOT better than the TV set I was watching analog 480i cable on just 5 years ago. For a low bitrate internet-streamed media... I think this is very impressive, and it is technically HD as far as I understand the definition.

imt alking general. it is ok to watch small sized in wthe window. but for me it is ugly in fullscreen mode.
i just like 1080 highstream candies

coming back to the subject: for me playback is not a problem with low quality 720p internet clips, the main problem is internet connection it causes long time buffering.

on the other hand some people could have slow old cpus and faster internet ocnnection.
we have to wait few years to make everyone happy with hd videos i think.

[jagabo]

You also have to keep frame rate in mind. 24 fps is easier than 30 fps which is much easier than 60 fps.

[MysticE]

they should stop calling it HD. quality is poor as hell. those seettings you wrote shouldnt take much cpu power and should run smoothly on old cpus. but the quality... my god

I'm not sure if you're talking about my videos specifically, or just in general, the 720p compressed HD of the popular sharing sites these days.

Bottom line, no it doesn't look as good as uncompressed 1080p HD. However, I wouldn't call it "poor"... it looks A LOT better than the TV set I was watching analog 480i cable on just 5 years ago. For a low bitrate internet-streamed media... I think this is very impressive, and it is technically HD as far as I understand the definition.

I have no idea what nitro1973 is talking about, it looks very nice to me in fullscreen (there was a bit of shakiness on some ground scenes though). I did have to let it load though as my rather fast connection (5069 kb/s) could not play it live.

He said he was pretty sure it was his laptop running poorly in general (needing defrag and cleared HDD space), not the processor.

I don't think that has anything to do with it. With modern systems, NTFS and today's fast hard drives defragging is no big deal. My drives are always full, even after a defrag I'm still at 30% Total Fragmentation, everything works fine.

I do have an onboard ATI/AMD HD3200 (paired with a dual core AMD Athlon 64 X2 5000+ @ 2900 MHz) which handles HD content extremely well though.

Cool vid, was fun to watch. Seeing as most will have to let it load you may want to shorten it a bit though.

[The111]

I did have to let it load though as my rather fast connection (5069 kb/s) could not play it live.

Seeing as most will have to let it load you may want to shorten it a bit though.

Hmm, you're obviously not getting 5Mbps to my server. The files are 2Mbps, and I've tried them from a few different broadband connections (all in the Houston area) and for a 4 minute video it's usually fully buffered within a minute or so.

[jagabo]

I have about a 5 Mb connection and I had no problem playing it live. It started playing within a second of pressing the play button and the seek bar was filled in a little over a minute (I cleared the cache before playing).

Regarding the quad core laptop not playing the video smoothly off a local drive -- my guess is a video card issue.

[MysticE]

I did have to let it load though as my rather fast connection (5069 kb/s) could not play it live.

Seeing as most will have to let it load you may want to shorten it a bit though.

Hmm, you're obviously not getting 5Mbps to my server. The files are 2Mbps, and I've tried them from a few different broadband connections (all in the Houston area) and for a 4 minute video it's usually fully buffered within a minute or so.

Hmm...



Seems odd, I'm out of Chicago. Just tried again and I can't keep up.

[The111]

Well, I'm in Houston... no idea where my Godaddy server is located.

[minidv2dvd]

most likely scottsdale arizona. if you are on a shared linux box the outbound bandwidth available to your site will vary enormously throughout the day.

[jagabo]

To Scottsdale I get about 5400 kbps up, 2800 kbps down according to Speedtest.net.

[MysticE]

To Scottsdale I get about 5400 kbps up, 2800 kbps down according to Speedtest.net.

A bit slower for me.

[jagabo]

Sorry, I just noticed I posted my Scottsdale numbers backwards. I get 5400 kbps DOWN and 2800 kbps UP. Ping time is about 70 ms. I tested in the middle of the night and got slightly (~10 percent) higher numbers.

[The111]

Certain settings are more cpu intensive for decoding than others; e.g. the high reference frames might make or break smooth playback on older cpus, but the same video @720p, same bitrate but lower quality settings might be able to play smoother. e.g. HD Apple movie trailers @ 1080p can even play smooth on some older single core CPUs because of lower settings (AVC Main, 2-3 ref frames, etc....). That is the price you pay for better quality/compression, and that will mean some people will get jerky playback. Besides the bitrate & resolution, CABAC and deblocking are also CPU resource hogs.

Poison, you have been a large source of info on every post I've made in the past few days. Question: where do you obtain all this info? (Why do I have a feeling you're going to say these very forums) For example, I have no idea what a reference frame even is, and why having more of them eats CPU power on playback. I have lots of wonderful settings recommendations from you and others in my previous thread, but I'd love to have more technical understanding of what each of those settings means. IS there anywhere that all this info is presented comprehensively... an x264 encoding options primer, or something?

[lordsmurf]

You need to work on your compression, it's not very good. On my main system, it jerks a lot, and it is slow to load. Too much bitrate, resolution maybe too high (encode 640x360 and scale higher on page view if it really needs to be larger), and the encoder that was used may not be very good, or have bad settings.

[poisondeathray]

The111 - A lot can be learned from here, and especially Doom9 where all the developers can be found. I learn a lot from trial and error - ie. what settings are appropriate for what situations or genres/types of material. For basic reference , you can look at the wiki, but you can't replace learning though experience. http://mewiki.project357.com/wiki/X264_Settings

Encoding settings are only part of the equation. The post-processing/filtering also plays a huge role. e.g. gentle denoising can reduce your bitrate requirements by 10-30% even on clean source footage. Even little things along the way, like keeping lossless as much as possible (e.g. using debugmode instead of .m2t re-rendering as we discussed earlier) add up to maintain quality, especially in this low bitrate scenario (2000kbps is considered low bitrate for 720p)

As I said earlier, some people may have difficulties playing back on older systems, you can use lower quality settings if you want, lower bitrate or resolution - these are tradeoffs you have to make taking your audience and bandwith constraints into consideration. You could use the Mainconcept encoder, but you saw the inferior results from that in the other thread...One major benefit of using x264 is that it is so highly configurable.

IIRC, you had a LQ option (lower bitrate/resolution) for those with older systems/slower connections, but it seems to be missing on that page now; IMO it would be a good idea to keep 2 versions to cater to a largest audience.

[The111]

You need to work on your compression, it's not very good.

I'll be the first to admit I don't know much about this stuff... but I was under the impression that going from 25Mbps to 2Mbps, and retaining most of the visual quality... well that's "good" compression (i.e. a 1250% compression). If I'm wrong, here's a source clip: http://www.matthoover.com/1080.m2t Please show me how "better" compression is possible (i.e. a smaller filesize with the same or greater quality than my 2Mbps version). I had quite a few people in my last thread telling me I needed MORE than 2Mbps to get decent quality.

Too much bitrate

Again, I'd love to be shown how to achieve my goal with LESS bitrate, but I am not aware of how.

resolution maybe too high

HD was my goal from the beginning...

and the encoder that was used may not be very good, or have bad settings.

I used x264 (which I've seen nothing but praise for), and I used settings recommended by posiondeathray who seems pretty freakin' knowledgable to me...

I do appreciate your feedback that this is playing back poorly on your system. Here is a question that would help me a lot more. Do Vimeo and YoutubeHD play back poorly on your system also? Thanks!

[The111]

IIRC, you had a LQ option (lower bitrate/resolution) for those with older systems/slower connections, but it seems to be missing on that page now; IMO it would be a good idea to keep 2 versions to cater to a largest audience.

Yeh, that was originally how the other thread started. I removed it because I was in a hurry but I'm seriously considering putting it back. Thinking, maybe... 320p, 24fps, 400kbps (?)... can I still use x264 and high ref frames, deblocking, etc, or will that still cause some CPU's problems even with the low res and bitrate?

[poisondeathray]

The111 - basically if you lower the quality, retain less detail, it will play smoother. Again, these are tradeoffs you have to make. YoutubeHD plays smooth because it uses AVC Main or Baseline, lower reference frames, lower quality settings - this makes it accessible to a larger audience, but the quality at a given bitrate is crap. They are moving to use x264 as well, which has been in beta for Youtube for a few months.

No, with those settings, at sd frame size, 500kbps, you can even play on a 5-year old single core CPU.

The fact is the settings you used were better compression, not worse. I mean in terms of efficiency i.e. a certain level of quality at a given bitrate. (it might be "not good" or inappropriate in the sense that not all PC's can play it back smoothly - again a tradeoff)

[The111]

The fact is the settings you used were better compression, not worse. I mean in terms of efficiency i.e. a certain level of quality at a given bitrate. (it might be "not good" or inappropriate in the sense that not all PC's can play it back smoothly - again a tradeoff)

Thanks, that's pretty much how I saw it too.

I owe you several e-beers for your continued assistance over the past week...

[poisondeathray]

To illustrate the difference, here are 1000kbps 720x400 encodes from Planet Earth blu-ray. Higher quality settings retain more detail & quality at a given bitrate i.e. it can be said to be more efficient or better compression. You can save the following images to your desktop and flip between them:

Mainconcept , AVC Main, 2 ref frames (direct export from Sony Vegas)


Mainconcept, AVC High, 3 ref frames, HQ settings (Mainconcept Reference)


X264, AVC High, 3 ref frames, HQ settings


As we discussed, the bundled Mainconcept version with Vegas is handicapped, and you have very limited options. The retail Mainconcept Reference is much nicer, but still lacks many of the options that x264 has (e.g. luminance masking, psy options), and tends to oversmooth. Even at equivalent settings, it tends to be much smoother, less detail. If you want to see some more comparisons with different genres, have a look at an older post here (scroll down) https://forum.videohelp.com/topic358132.html

Compression codecs generally work by analyzing the differences & changes between a reference frame. So if the inital ref frame is a still picture of a plant, and the next few subsequent frames have no motion and is the same picture, it requires very little bitrate to encode the differences. In contrast, a big action sequence with lot of explosion and visual noise will require a lot. (This is the rationale for using denoising filters to aid in compression - a whole other HUGE topic ) A higher number of ref frames will aid compression for this reason - there is a longer sequence where the differences to be analyzed is allowed, and it doesn't have to waste bitrate on specifying a new sequence.

PS. you should also instruct viewers to upgrade to the latest Adobe flash player if they are still on 9; v10.0.12.36 added improved hardware acceleration, better anti-aliasing and several other improvements

[The111]

Good info, I hope to become better versed on all this in the near future.

Flash 9 actually won't load H.264 at all. Earlier I was using OVP (Open Video Player), and by specifying "10.0.0" required in the page source, it would bring up a nifty little button in the player prompting user to upgrade. With JW player I'm using now, it just won't show the player at all if your version doesn't match what's in the souce, and you'll see a little GIF behind the player telling you to go to Adobe.com and upgrade. I guess I could require higher than 10.0.0, but not sure if I want to inconvenience people just for a sub-version upgrade.

[poisondeathray]

Flash 9 actually won't load H.264 at all.

Actually v9.0.115.0 was the 1st version that supported h.264 . Later releases fixed some flaws, security bugs, added AAC support. v10.0.12.36 added hardware acceleration, so it may or may not provide a smoother experience on older systems - I haven't seen benchmarks or head-to-head testing on that

http://en.wikipedia.org/wiki/Adobe_Flash_Player

[The111]

Hmm, weird. I downloaded some old flash versions for website testing. Installed one of the most recent (latter) 9's (forget exact number)... and it wouldn't load my site at all. (edit: and this was before I changed the version number in my page source to 10.0.0) (double edit: nevermind... apparently 9 works with JW and h.264... guess it was just OVP that required 10)

[The111]

Another thing I've noticed is that even with a powerful CPU/GPU... the videos tear from time to time when I am viewing them. It's of course not repeatable... if I rewind and replay the section that I saw tearing on, it will usually play clean the second time.

Any explanation for this, or an easy way to avoid it? Is it still related to the high compression and power required for playback?

[jagabo]

You need a player that supports video overlay to avoid tearing. Web based players do not support this.

Tearing occurs when the frame buffer is updated by the player while the graphics card is displaying it. You end up seeing part of two different frames in one redraw cycle. The solution is to change the frame buffer only during the vertical blanking interval. This is usually done by double or triple buffering and changing the video overlay's frame buffer pointer during vertical blanking.