PureVideo HD (VP2) Really Helps

So recently, thanks to the generosity of a friend, I was able to swap my 8800 GTS (640MB) for his spare 9800 GTX (512MB). While there is a noticeable increase in gaming performance, where I REALLY noticed a difference was in HD-DVD and H.264 decoding. My brother recently purchased a Canon Vixia HD camcorder, which records 17Mb/s H.264 AVCHD encoded video. The video is beautiful, but on my Core 2 Duo E6600 (2.4GHz) & nVidia GeForce 8800 GTS combination I was unable to play it at anything near native frame rate. The CPU would sit at 100% CPU and would render a couple frames every couple seconds. Not nearly watchable.

Using the same CPU along with the 9800 GTX, however, it's an entirely different picture (as long as you use a PureVideo HD enabled player). Using Media Player Classic Homecinema (which is DXVA enabled), the video runs smooth as butter on my system, with only a couple percent CPU usage.

It is a similar story with HD-DVD, though quite not so startling. With my 8800 GTS, when playing h.264 encoded discs it would be relatively smooth, but not completely, and every fifteen minutes while playing VC1 encoded discs it would stutter for a moment. No longer. The 9800 GTX does enough of the processing that my CPU now sits around 20% usage, and the video plays stutter free and completely smooth for the h.264 encoded discs.

So, in summary, VP2 really improved HD playback over VP1 (which was in my 8800 GTS 640MB). Make sure that whatever video player you use supports PureVideo HD or DXVA to get the most benefit.Also, try out MPC Homecinema if you want to do some HD video watching with a VP2 equipped system.

Additional Reading: HD Video Decode Quality and Performance Summer '07

Audio Path for ABC, CBS, NBC, PBS

So I was looking for a price list on Dolby multichannel encoders, and came across this page. Dolby has PDFs available for ABC, CBS, NBC & PBS detailing the pathway the original feed takes from satellites through your local affiliate and finally into your HDTV. It is interesting to note that only NBC gives the local station the full uncompressed audio stream to all it's affiliates. ABC does give a nice 640Kb/s AC3 stream however, and CBS gives a Dolby E stream (a Dolby technology which encodes up to an 8 channel digital stream into 2 uncompressed audio channels). Now if only all the local stations could give Bozeman the surround sound goodness available in the source (KTVM excepted, of course).

Snapshots of Each Channel

So here are some snapshots from each channel I can receive, along with the program I recorded it during for the HD channels. For the SD channels I'm not actually sure what each program is, as I never really watch them :-). All of these images were taken from the original transport stream using VLC with the Linear deinterlace filter on. Without further adieu, here they are (be sure to click on each image to see it at full resolution)!

KBZK-DT CBS (Numb3rs)


KBZK-CW CW (Unknown, feel free to leave a comment with what the show is)
KUSM-HD PBS (Nova)

KUSM-DT PBS

KTVM-HD NBC (Monk)

HDHomeRun

So late last year I needed a way to view OTA HD broadcasts. I searched around, and while I originally was thinking about purchasing a PCI or USB based capture device, a friend mentioned that he had been looking at the SiliconDust HDHomeRun device.

Essentially the HDHomeRun is an ATSC/QAM tuner with an Ethernet output. The device connects to an over the air antenna or unencrypted cable coax jack and then sends beautiful MPEG2 signals across your home network. They have a rather primitive Config tool for windows to allow you to look up and view channels, but to really use the device you should connect it to MythTV, BeyondTV, or some other computer based DVR program (I personally use MythTV and highly recommend it).

Next post: a review of the Over-The-Air Digital signals in my area!