Poor 1080p playback

I built an HTPC for a 42" Hyundai 1080p LCD that I bought before christmas for $999 on newegg, and the TV for the most part is great. However, 1080p performance isn't as great as I'd expect it to be

HTPC:
Core 2 Duo E4500 @ stock (2.2Ghz)
2GB DDR2-667 in dual channel
ATI Radeon 1950XT 512MB PCI-e
GIGABYTE GA-73VM-S2 Micro ATX
Windows XP Pro (x86)

Just watched Spiderman 3, encoded (x.264) @ 1920x1080, and whenever all of the sand would come onto the screen, as well as other more complex scenes, the movie would just freeze.

I should note that I have not experienced this type of playback in other movies with less motion/complex scenes, and also that I for the most part use VLC as the player.

Any ideas?

Monitor your CPU usage during these scenes and report back what it's maxing out at.

Also, while VLC is a pretty good all-in-one player, I'm not convinced it's internal decoders are good enough for very high bitrate 1080p playback. Your experiences may be proving that.

yeah i think if anything would be limiting it, it would be the cpu. even though its a c2d, its kinda low clocked.

I don't think the X1950XT serves well as an HTPC card. It doesn't provide the same hardware accel for HD as the 24/26/3800 series from ATI or the 84/85/8600 series from nvidia.

You should be able to fix the problem but OCing the CPU though if you don't want to spend the $$$ on a new card.

i'm leaning towards VLC being the problem, as i've done some googling and people have experienced poor framerates using VLC/Quicktime for h264 encoded movies @ 1080p

i've never had any framerate problems with this system at 1080p, in fact nothing even remotely close to it. everything else has played without a hitch (Shrek the 3rd, Rush Hour 3, King Kong to name a few)

i have a feeling it'll end up either being the encoding of the movie was screwed up, or VLC doesn't like it. i seriously doubt it's because my C2D isn't clocked at 3ghz or higher, or because my 1950XT isn't fast enough

let me be clear again, the movie comes to a complete stand still at certain points in the film, when there is lots of small individual movements going on (like a zoomed out view of lots of people in a city street, or individual grains of sand on the uh.. convict guy)

the rest of the movie runs flawlessly

PC world had an article testing CPU loads on Hi-Def playback and found most CPU's above 1.2g would do the movies as long as a decent vid card was attached. I'd try a different player.

Your CPU is NOT the problem. I've got a Pioneer Kuro Pro 60" (that's not actually relevant so, yeah, I'm just bragging) running off an AMD X2 3800+ that plays back 1080p, with frame cleaning done by ffdshow post processing and avisynth scripts, without breaking a sweat.

In general, you do not want a heavily muscled CPU on a HTPC. You want the slowest, coolest, least power draining CPU that will do what you need. If you want to game, do what I do, have a gaming PC in addition to your HTPC hooked up to your TV and use the longest HDMI cable that won't degrade quality so you can keep it from visually messing up your nice setup. The reason for that is because the HTPC is always on (mostly in S3), is in a small case, is silent and is only used for playing media and doing light tasks. You are already going to be running the highest end video card that can take a passive heat sink, so you do not want anything else to generate heat. A high power CPU on a passive heatsink is going to general a lot of heat. Even my X2 3800+ generates more heat than I want.

To your problem. VLC is actually the worst playback app for a HTPC IMO. It has a lousy interface for a remote and is generally a codec noobs' tool, and useless for fine tuning quality and producing the best picture possible. There are a couple of good stand alone players. One is Zoom Player and the other that I now use is called KMplayer. I like it because its more stable than Zoom and integrates ffdshow.

Whatever you use, you need to switch to a directshow player and use coreavc for decoding your avc/h264 video. If you really are not into learning and working with codecs, and are looking for a stand alone player, then I would recommend you use cyberlink's powerdvd ultra for playback.

silkshadow said:

One is Zoom Player and the other that I now use is called KMplayer. I like it because its more stable than Zoom and integrates ffdshow.

Whatever you use, you need to switch to a directshow player and use coreavc for decoding your avc/h264 video. If you really are not into learning and working with codecs, and are looking for a stand alone player, then I would recommend you use cyberlink's powerdvd ultra for playback.

Click to expand...

no, i'm definitely fine with learning how to properly set this up. could you give me some pointers, and some information on the software that you mentioned (other than PowerDVD Ultra, not really up for an easy way out, i'm willing to be as detailed as possible)

My bad, I should've included links. :doh:

KMplayer- http://www.kmplayer.com/
Zoomplayer- http://www.inmatrix.com/
CoreAVC - http://www.coreavc.com/

Both players are free, though ZP requires a fee for playing back DVD discs and if you want to change the default codec for something (I will explain this below and help you get started). CoreAVC is commercial.

ZP comes with one nice feature which is the install center. That thing downloads codecs for you. However, KMplayer comes with everything you need out of the box. So you can start with KMplayer and then tweak things you want to improve by getting alternative codecs. KMplayer has more options and is more powerful but can be a bit more complex. They have a nice forum for help, its better than ZP's forum.

Ok, getting you started on Codecs. The codec directshow uses for decoding a specific format is based on the filter's "filter merit". If you buy ZP pro, it will ignore the filter merit and you can select what codec ZP uses. You an use a program like radlight filter manager (no stable link anymore but google should produce an archive for it) to set your codec merits. FFDshow has a GUI for selecting which codecs it will take the highest merit for.

Basically, FFDshow is 90% of what you need for video decoding. It is open source and free. It has forked a few times though and even just figuring out which version to use can be confusing. If you use KMplayer, you can ignore this problem. They integrate ffdshow into the player and use the best build that works with it. For the standalone ffdshow, I've been alternating from the versions posted at afterdawn and the ffdshow tryouts. I am currently recommending the ffdshow tryouts: http://ffdshow-tryout.sourceforge.net/.

Besides the basics like divx, xvid and the like it will also handle quicktime, FLV, realmedia and a host of other obscure codecs. It does these the best. The codecs its does not do well with are the WMV codecs (including VC1) and AVC (h264/x264/etc). For AVC, as I suggested, I like CoreAVC. For the WMV ones (except VC1 which coreAVC does best) I've been forced to use the MS codecs and then pipe it into ffdshow for post processing.

Post processing is where you can loose a big part of your life if you are on the quest for the perfect picture. It is purely subjective and dependent on the setup of your hardware. So no one's settings will work for you. I have 4 HTPCs attached to 4 different TVs/receivers and each have different post processing settings. The main one you will definitely want to use is the upscalling/resizing filter. This will make lower res content (such as SD and the low quality TV/movie rips you download) much prettier on your 720p/1080p display. However, if you have the bandwidth, I'd recommend using usenet or join a private bittorent tracker to get 1080p (or in a pinch 720p) rips.

FFDshow does audio decoding as well. Again, something you don't have to think about if you use KMplayer, till you run into a quality issue or problem. There is another audio filter called AC3Filter: http://ac3filter.net. I used to favor it before I switched to KMplayer. Now I let FFdshow do almost all my audio decoding, including AC3 passthrough.

Hope that helps to get you started. For more info you should check out AVSforums and Doom9. Doom9 is the best forum for this kind of material but they can be hard on noobs. From there the forums of the HTPC apps you end up using will finish off your end user experience.

Edit: Oops, forgot about splitters. Generally, Haali's media splitter (http://haali.cs.msu.ru/mkv/) and the default source spliiters will do what you need (though, just to note, proprietary formats tend to need splitters like FLV, quicktime, realmedia, etc). Haali is automatically installed with CoreAVC. I've switched to using Nero's digital parser for some containers because Haali seems to block ffdshow post processing for some formats (off the top of my head VC1 and quicktime were two of those). However, you need to install Nero's showtime to get access to that splitter.