[mythtv] jerky/jittery video on fast box?
John Joseph Roets
jjr at sunflower.com
Tue Jan 21 14:47:32 EST 2003
I'm running Myth and getting jerky/jittery video.
Video is jittery to very jittery in live TV mode (and sometimes, in
playback mode). It seems that the mpeg4 setting gives me better
quality, yet is much more jerky. I've been recording with rtjpeg
settings below, and have gotten very large files (~3300-5400 KB/hr.) as
a result (I will ask that question next, after I see the file sizes
generated today with mpeg4 settings).
I was hoping that it was due to dma settings, but that is apparently not
Would I gain much in not compressing the audio?
Is there something in my system which inherently causes/allows this?
Any help would be greatly appreciated.
Thanks in advance.
IBM Netvista P4 @ 1.8 GHz 256MB RAM
ATI TV-Wonder VE
Intel i810 onboard sound with ALSA
nVidia Vanta/Vanta LT (AGP)
RH 8.0 -- Gnome
AVermedia AVerkey iMicro VGA to NTSC box
54 in. rear-projection bigscreen
- What version of MythTV are you running?
- settings file
All other settings in settings.txt are default, no change.
- What resolution?
480x480 (I've tried 640x480, as it should work fine with this box, and
while it is clearer, it causes much slowdown/jitter).
- What codec are you using?
rtjpeg -- less jitter, but still some. Quality at 255
mpeg4 -- seems better quality, but certainly more jitter. Target
bitrate at 2200.
- Are you using the nvidia binary driver?
- Is your mysql colocated on the server with mythtv?
- What is your disk speed? 7200? 5400? Other?
- HD info [hdparm -I /dev/hda]?
ATA device, with non-removable media
Model Number: MAXTOR 6L040J2
Serial Number: 662205637151
Firmware Revision: A93.0500
Used: ATA/ATAPI-5 T13 1321D revision 1
Supported: 5 4 3 2 & some of 6
Logical max current
cylinders 16383 16383
heads 16 16
sectors/track 63 63
CHS current addressable sectors: 16514064
LBA user addressable sectors: 78177792
device size with M = 1024*1024: 38172 MBytes
device size with M = 1000*1000: 40027 MBytes (40 GB)
LBA, IORDY(can be disabled)
bytes avail on r/w long: 4 Queue depth: 1
Standby timer values: spec'd by Vendor, no device specific
R/W multiple sector transfer: Max = 16 Current = 16
Recommended acoustic management value: 128, current value: 254
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5
Cycle time: min=120ns recommended=120ns
PIO: pio0 pio1 pio2 pio3 pio4
Cycle time: no flow control=120ns IORDY flow control=120ns
* READ BUFFER cmd
* WRITE BUFFER cmd
* Host Protected Area feature set
* Write cache
* Power Management feature set
Security Mode feature set
* SMART feature set
* Mandatory FLUSH CACHE command
* Device Configuration Overlay feature set
* Automatic Acoustic Management feature set
SET MAX security extension
* DOWNLOAD MICROCODE cmd
* SMART self-test
* SMART error logging
Master password revision code = 65534
not expired: security count
not supported: enhanced erase
20min for SECURITY ERASE UNIT.
HW reset results:
CBLID- above Vih
Device num = 0 determined by CSEL
- What is your disk buffer size? 2MB? Other?
[ cat /proc/ide/hda/cache ]
- What are your dma, multcount, and prefetch settings?
[ hdparm /dev/hda ]
multcount = 16 (on)
IO_support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 0 (off)
readahead = 8 (on)
geometry = 4866/255/63, sectors = 78177792, start = 0
- What are your "elevator" settings? [ elvtune /dev/hda1 ]
/dev/hda1 elevator ID 0
- What is your CPU and bus speed? [ cat /proc/cpuinfo ]
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 1
model name : Intel(R) Pentium(R) 4 CPU 1.80GHz
stepping : 2
cpu MHz : 1794.252
cache size : 256 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm
bogomips : 3567.44
- What is your memory type, speed, configuration, and size?
- What is your motherboard chipset? [ a function of `cat /proc/pci` ]
[root at mythtv root]# cat /proc/pci
PCI devices found:
Bus 0, device 0, function 0:
Host bridge: Intel Corp. 82845 845 (Brookdale) Chipset Host Bridge
Prefetchable 32 bit memory at 0xf4000000 [0xf7ffffff].
Bus 0, device 1, function 0:
PCI bridge: Intel Corp. 82845 845 (Brookdale) Chipset AGP Bridge
Master Capable. Latency=96. Min Gnt=12.
Bus 0, device 30, function 0:
PCI bridge: Intel Corp. 82801BA/CA/DB PCI Bridge (rev 18).
Master Capable. No bursts. Min Gnt=6.
Bus 0, device 31, function 0:
ISA bridge: Intel Corp. 82801BA ISA Bridge (LPC) (rev 18).
Bus 0, device 31, function 1:
IDE interface: Intel Corp. 82801BA IDE U100 (rev 18).
I/O at 0x1800 [0x180f].
Bus 0, device 31, function 2:
USB Controller: Intel Corp. 82801BA/BAM USB (Hub #1) (rev 18).
I/O at 0x1820 [0x183f].
Bus 0, device 31, function 3:
SMBus: Intel Corp. 82801BA/BAM SMBus (rev 18).
I/O at 0x1810 [0x181f].
Bus 0, device 31, function 4:
USB Controller: Intel Corp. 82801BA/BAM USB (Hub #2) (rev 18).
I/O at 0x1840 [0x185f].
Bus 0, device 31, function 5:
Multimedia audio controller: Intel Corp. 82801BA/BAM AC'97 Audio
I/O at 0x1c00 [0x1cff].
I/O at 0x1880 [0x18bf].
Bus 1, device 0, function 0:
VGA compatible controller: nVidia Corporation Vanta [NV6] (rev 21).
Master Capable. Latency=248. Min Gnt=5.Max Lat=1.
Non-prefetchable 32 bit memory at 0xf0000000 [0xf0ffffff].
Prefetchable 32 bit memory at 0xf8000000 [0xf9ffffff].
Bus 2, device 8, function 0:
Ethernet controller: Intel Corp. 82801BA/BAM/CA/CAM Ethernet
Controller (rev 3).
Master Capable. Latency=66. Min Gnt=8.Max Lat=56.
Non-prefetchable 32 bit memory at 0xf2000000 [0xf2000fff].
I/O at 0x2000 [0x203f].
Bus 2, device 14, function 0:
Multimedia video controller: Brooktree Corporation Bt878 (rev 17).
Master Capable. Latency=132. Min Gnt=16.Max Lat=40.
Prefetchable 32 bit memory at 0xfb000000 [0xfb000fff].
Bus 2, device 14, function 1:
Multimedia controller: Brooktree Corporation Bt878 (rev 17).
Master Capable. Latency=33. Min Gnt=4.Max Lat=255.
Prefetchable 32 bit memory at 0xfb001000 [0xfb001fff].
- What is your kernel version? [ uname -a ]
Linux mythtv 2.4.18-19.8.0 #1 Thu Dec 12 05:39:29 EST 2002 i686 i686
* john joseph roets
* joe at createtank.com
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