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
Tuesday, January 13, 2009
Friday, November 14, 2008
VideoLAN Client Dynamic Range Compression
A little note on something related to my earlier post.
By default VLC's Dolby decoder follows Dynamic Range Compression (sometimes called DRC) encoded into AC3 files. While this is great for TV's built in speakers and the tinny PC speakers that came with your Packard Bell, that isn't optimal for THX certified home theater systems.
Thankfully it's easy to fix the issue. The following instructions are with respect to VLC 0.9.6.
1. Start up VLC.
2. Click Tools, then Preferences.
3. At the bottom of the Preferences screen, click All.
4. In the left list, click Input/Codecs, Audio codecs, then A/52.
5. Uncheck A/52 dynamic range compression.
6. While you're there, click DCA (stands for DTS Coherent Acoustics, the DTS codec used in DVDs, not to be confused with the Theatrical DTS codec) in the left list, and uncheck DTS dynamic range compression.
7. Click Save.
Now you can enjoy your HDTV/DVDs with a dynamic range you didn't think was possible!
By default VLC's Dolby decoder follows Dynamic Range Compression (sometimes called DRC) encoded into AC3 files. While this is great for TV's built in speakers and the tinny PC speakers that came with your Packard Bell, that isn't optimal for THX certified home theater systems.
Thankfully it's easy to fix the issue. The following instructions are with respect to VLC 0.9.6.
1. Start up VLC.
2. Click Tools, then Preferences.
3. At the bottom of the Preferences screen, click All.
4. In the left list, click Input/Codecs, Audio codecs, then A/52.
5. Uncheck A/52 dynamic range compression.
6. While you're there, click DCA (stands for DTS Coherent Acoustics, the DTS codec used in DVDs, not to be confused with the Theatrical DTS codec) in the left list, and uncheck DTS dynamic range compression.
7. Click Save.
Now you can enjoy your HDTV/DVDs with a dynamic range you didn't think was possible!
MythWeb buggering on NBC
So a little while ago I wanted to pull up a Chuck I had recorded OTA from our local NBC affiliate using MythTV. Seeing as how my home theater PC is Windows currently (VLC, and therefore Linux can't handle Dolby TrueHD or DTS-HD Master yet unfortunately), I used MythWeb to download the episode to my hard drive, and tried to play it using VLC for Windows.
I was greeted with no audio, and a video track that went through the entire ~hour episode in a matter of minutes. It would show a couple seconds of a scene, then skip forward a number of minutes, rinse and repeat.
I tried downloading the file again, and then tried opening on Linux VLC on a different computer. No go, same issues. A friend of mine who originally got me into MythTV suggested I try reencoding the video using mythtranscode. A bit of research later, and I entered the following command into the Linux command line:
mythtranscode --infile /var/lib/mythtv/recordings/1061_20081110185800.mpg --mpeg2 --showprogress --outfile /home/pcjjman/videos/chuck.mpg
Most of the options are self-explanatory. The --mpeg2 tells mythtranscode to convert the TS stream to a PS stream, and reencode any frames next to commercials. The end result of the operation was the reencoded file played perfectly and I was able to enjoy Chuck in 1080i and 5.1. It also allowed me to skip through the episode using the Alt-Arrow Keys shortcuts in VLC, which didn't work previously.
So if you download a file straight off MythWeb and it's not playing correctly, try reencoding it. It might just do the trick.
I was greeted with no audio, and a video track that went through the entire ~hour episode in a matter of minutes. It would show a couple seconds of a scene, then skip forward a number of minutes, rinse and repeat.
I tried downloading the file again, and then tried opening on Linux VLC on a different computer. No go, same issues. A friend of mine who originally got me into MythTV suggested I try reencoding the video using mythtranscode. A bit of research later, and I entered the following command into the Linux command line:
mythtranscode --infile /var/lib/mythtv/recordings/1061_20081110185800.mpg --mpeg2 --showprogress --outfile /home/pcjjman/videos/chuck.mpg
Most of the options are self-explanatory. The --mpeg2 tells mythtranscode to convert the TS stream to a PS stream, and reencode any frames next to commercials. The end result of the operation was the reencoded file played perfectly and I was able to enjoy Chuck in 1080i and 5.1. It also allowed me to skip through the episode using the Alt-Arrow Keys shortcuts in VLC, which didn't work previously.
So if you download a file straight off MythWeb and it's not playing correctly, try reencoding it. It might just do the trick.
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