Need a super intense 1080p test file

[obeseotron]

I'm building an htpc in the near future and need to decide on specs. To do so I'm looking for the most the most computationally intense video file I can find. Format does not matter, software I'm using will play anything. I don't want any links to anything illegal, just the most demanding legal 1080p file someone can find.

FTR I'm replacing my xbox1 w/ xbmc with a linux box running the port of xbmc, which has made a ton of progress recently. It's still in alpha, but I've managed to get a recent revision to compile and work well enough on my desktop and laptop that I can test files against it to determine specs for the PC. I'm trying to limit heat and power more than save money, so I just want the coolest running chip that can handle any size or type of media.

 

[Auric]

Heh, well the "illegal" schtuff is not very demanding. That is, the streams from commercial discs are virtually fully decoded by GPU and only utilize a few percent of CPU. The other option is a dedicated device such as based upon Syabas NMT. Otherwise, if intending a brute-force approach with software-only decoding on a general purpose CPU, then the power and heat situation ain't gonna be pretty. Is Linux capable of GPU acceleration?

Higher bitrate schtuff is available from footagehouse, for one.

 

[dwell]

You can find 1080p encodes of Elephants Dream. I really don't know what makes an encode more computationally intense though.

http://www.elephantsdream.org/

 

[Auric]

Originally posted by: Chris
You can find 1080p encodes of Elephants Dream. I really don't know what makes an encode more computationally intense though.

http://www.elephantsdream.org/

What are the codecs and bitrates though? It seems like the 1080p is ASP while the AVC is lower resolution. So, it seems unlikely they are even as demanding as Apple trailers which themselves are decidely unbenchmark worthy.

 

[obeseotron]

Originally posted by: Auric
Heh, well the "illegal" schtuff is not very demanding. That is, the streams from commercial discs are virtually fully decoded by GPU and only utilize a few percent of CPU. The other option is a dedicated device such as based upon Syabas NMT. Otherwise, if intending a brute-force approach with software-only decoding on a general purpose CPU, then the power and heat situation ain't gonna be pretty. Is Linux capable of GPU acceleration?

Higher bitrate schtuff is available from footagehouse, for one.

You're right that most illegal stuff isn't very demanding. Rip groups specialize in re-encoding content at low bitrates while retaining as much quality as possible - most TV shows you see on bittorrent are in the 3mbps range for 720p and 5-6 for 1080p (taken from a 1080i source). I don't think you're right that the gpu does almost all of the decoding - in a limited number of apps you can decode certain types of streams with the gpu doing most of the work if you have a newer card. While linux is theoretically capable of offloading to the gpu, there isn't support there now, and considering how limited support is on the Windows side, I have no faith it will ever be there on linux.

I eventually found a 35mbps 1080p h.264 clip from planet earth of a huge flock of birds. This seems like a reasonable worst case scenario to me. I won't post a link because I don't know exactly how legal it is. I tested on a 2.2GHz Core 2 Duo laptop and a 3.1GHz Core 2 Quad overclocked desktop. The laptop breezed through everything else, but could only hit about 20fps on the 24fps bird clip. The desktop managed fine. The build script for xbmc automatically detects the number of cores you have and compiles it appropriately - it seems to scale almost linearly with additional cores, which is sorta expected for media decoding. Looks like to be safe I'll want either a 3GHz Core 2 Duo or basically any quad.

XBMC is the only solution I'm interested in.and that means running on linux. There is a MacOSX port as well, but a mac mini is too slow based on my tests. The GUI, compatibility and flexibility of xbmc is so far beyond anything else available that I don't care about any other way of streaming media. I have never encountered a file my xbox can't play for any reason besides cpu speed. The hardware in some dedicated streamers is OK and is a lot more efficient than a general purpose x86 cpu, but they all have interfaces or format compatibility that pales in comparison to xbmc. Although it's in alpha now, it works well enough that I'm going to build the htpc to run it. I don't expect it to be stable enough to ditch my real xbox1 with xbmc for a while, but it's certainly functional.

 

[Auric]

Actually, I was referring to unmolested commercial content. Once the disc format overhead is stripped, the highest bitrate AVC and VC-1 place virtually no demand on CPU, given UVD.

The Planet Earth clip sounds intriguing as the BBC AVC broadcasts have been limited to 20 Mbps as far as I know (even during testing) and likewise for the VC-1 discs. Unless that is from some very early test or distribution feed perhaps the rate referred to is peak rather than average?

 

[obeseotron]

Auric, sorry for the confusion, you're absolutely right that playing hddvd and bluray can be done almost entirely by the GPU in windows with a newer video card. In the case of xbmc there isnt going to be support for offloading to GPU any time soon. The CPU does most of the work, the GPU just does scaling and post processing, regardless of the content.

I'm not sure what the source for that planet earth clip is, I assumed it was a transcode of the bluray or hddvd version. I understand this isnt ideal, but the test should still be valid. For comparison a 1080p trailer from apple seems to take only one third the power this one does. If you're interested I'll send it to you.

 

[Auric]

Have you confirmed the average bitrate with any tools such as Media Info? Perhaps you could PM me a source for the clip or even just the name.