<br><font size=2 face="sans-serif">I finally resolved my studder problem
(choppy audio/video) with Mythtv. The solution was to ensure I had
video drivers capable of xvideo. That may seem obvious to most of
you, but to this newbie, it was a revelation. I've noted here in
case anyone else is experiencing choppy video as something to check.</font>
<br>
<br><font size=2 face="sans-serif">I am using Jarod's (awesome) guide with
Fedora Core 1. Since I have a beefy system (Athlon XP 1800+, 120GB
drive, 1.5GB Ram), and hardware en/decoding (PVR-350), I couldn't figure
out why i had jittery/choppy/studdery video/audio when either watching
live tv and/or watching recorded TV. My CPU would hit 100% when attempting
to do these which is the cause of the choppiness. But what caused
the 100% CPU, especially given that I have the PVR350 which should handle
the en/decoding. I saw a post which helped trigger the lightbulb
icon over my head. It turns out, my problem isn't with the video
capture card, but the graphics card. While it's capable of xvideo
(not even sure what that is but it's important to smooth video I'm guessing),
I didn't have the requisite driver to ensure it was rendering Xv. While
I did follow Jarod's guide, I skipped the section titled "8. Get and
install video card drivers for TV out" because I wasn't outputting
to a TV, but rather to an LCD screen. Jarod accurately notes that
this step is optional, but I found it to be critical to me for smooth as
gravy video. </font>
<br>
<br><font size=2 face="sans-serif">To determine if my system was using
Xv, I typed this at a command prompt:</font>
<br>
<br><font size=2 face="sans-serif"># xvinfo</font>
<br>
<br><font size=2 face="sans-serif">and was returned the following:</font>
<br>
<br><font size=2 face="sans-serif">X-Video Extension version 2.2</font>
<br><font size=2 face="sans-serif">screen #0</font>
<br><font size=2 face="sans-serif">no adaptors present</font>
<br>
<br><font size=2 face="sans-serif">After following Jarod's guide to install
the video card drivers for TV out, the same command returned this (and
smooth video):</font>
<br><font size=2 face="sans-serif">X-Video Extension version 2.2</font>
<br><font size=2 face="sans-serif">screen #0</font>
<br><font size=2 face="sans-serif"> Adaptor #0: "NV04 Video
Overlay"</font>
<br><font size=2 face="sans-serif"> number of ports: 1</font>
<br><font size=2 face="sans-serif"> port base: 77</font>
<br><font size=2 face="sans-serif"> operations supported:
PutImage</font>
<br><font size=2 face="sans-serif"> supported visuals:</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x21</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x23</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x24</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x25</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x22</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x26</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x27</font>
<br><font size=2 face="sans-serif"> depth 16, visualID
0x28</font>
<br><font size=2 face="sans-serif"> number of attributes:
4</font>
<br><font size=2 face="sans-serif"> "XV_DOUBLE_BUFFER"
(range 0 to 1)</font>
<br><font size=2 face="sans-serif">
client settable attribute</font>
<br><font size=2 face="sans-serif">
client gettable attribute (current value is 1)</font>
<br><font size=2 face="sans-serif"> "XV_COLORKEY"
(range 0 to 16777215)</font>
<br><font size=2 face="sans-serif">
client settable attribute</font>
<br><font size=2 face="sans-serif">
client gettable attribute (current value is 2110)</font>
<br><font size=2 face="sans-serif"> "XV_AUTOPAINT_COLORKEY"
(range 0 to 1)</font>
<br><font size=2 face="sans-serif">
client settable attribute</font>
<br><font size=2 face="sans-serif">
client gettable attribute (current value is 1)</font>
<br><font size=2 face="sans-serif"> "XV_SET_DEFAULTS"
(range 0 to 0)</font>
<br><font size=2 face="sans-serif">
client settable attribute</font>
<br><font size=2 face="sans-serif"> maximum XvImage size:
2046 x 2046</font>
<br><font size=2 face="sans-serif"> Number of image formats:
4</font>
<br><font size=2 face="sans-serif"> id: 0x32595559
(YUY2)</font>
<br><font size=2 face="sans-serif"> guid: 59555932-0000-0010-8000-00aa00389b71</font>
<br><font size=2 face="sans-serif"> bits per
pixel: 16</font>
<br><font size=2 face="sans-serif"> number of
planes: 1</font>
<br><font size=2 face="sans-serif"> type: YUV
(packed)</font>
<br><font size=2 face="sans-serif"> id: 0x32315659
(YV12)</font>
<br><font size=2 face="sans-serif"> guid: 59563132-0000-0010-8000-00aa00389b71</font>
<br><font size=2 face="sans-serif"> bits per
pixel: 12</font>
<br><font size=2 face="sans-serif"> number of
planes: 3</font>
<br><font size=2 face="sans-serif"> type: YUV
(planar)</font>
<br><font size=2 face="sans-serif"> id: 0x59565955
(UYVY)</font>
<br><font size=2 face="sans-serif"> guid: 55595659-0000-0010-8000-00aa00389b71</font>
<br><font size=2 face="sans-serif"> bits per
pixel: 16</font>
<br><font size=2 face="sans-serif"> number of
planes: 1</font>
<br><font size=2 face="sans-serif"> type: YUV
(packed)</font>
<br><font size=2 face="sans-serif"> id: 0x30323449
(I420)</font>
<br><font size=2 face="sans-serif"> guid: 49343230-0000-0010-8000-00aa00389b71</font>
<br><font size=2 face="sans-serif"> bits per
pixel: 12</font>
<br><font size=2 face="sans-serif"> number of
planes: 3</font>
<br><font size=2 face="sans-serif"> type: YUV
(planar)</font>
<br>
<br>