DVD playback jerkiness

noxious · 09-08-2004, 04:50 PM

Playing back a dvd (after finding and installing libdvdcss, libdvdread and mplayer) results in "jerky" playback. Audio is fine - it almost seems like the refresh rate is too low - How can I increase the refresh rate for mplayer, xine and totem? I have the same problem with them all - to differing degrees, however.

My laptop's screen was down at 61khz, and I increased it to 80khz to see if that would do the trick - to no avail.

Thanks...

Tino27 · 09-08-2004, 05:54 PM

Make sure that you have DMA enabled for your CD-ROM/DVD drive. I believe that 'hdparm' is the command you are going to want to play with in order to get this to happen. Word of warning, of course, hdparm can do as much damage as it can do good, so I'd suggest a quick reading of the man page before trying it out.

shilo · 09-08-2004, 05:58 PM

You can use hdparm to check the current status of the drive. That is safe as can be.

Code:

hdparm /dev/XXX

WHere XXX is the device that you want to check out. That will tell you if you are using DMA.

noxious · 09-08-2004, 08:48 PM

This is what I got back after # hdparm /dev/hdb

/dev/hdb:
HDIO_GET_MULTCOUNT failed: Invalid argument
IO_support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 1 (on)
readahead = 8 (on)
HDIO_GETGEO failed: Invalid argument

What's this telling me? Does it need to be fixed?

noxious · 09-08-2004, 08:51 PM

Same thing for each device... (they're all really the same unit). I guess it looks like dma is being used...

/dev/dvd:
HDIO_GET_MULTCOUNT failed: Invalid argument
IO_support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 1 (on)
readahead = 8 (on)
HDIO_GETGEO failed: Invalid argument
bash-3.00# hdparm /dev/cdrom

/dev/cdrom:
HDIO_GET_MULTCOUNT failed: Invalid argument
IO_support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 1 (on)
readahead = 8 (on)
HDIO_GETGEO failed: Invalid argument
bash-3.00# hdparm /dev/hdb

/dev/hdb:
HDIO_GET_MULTCOUNT failed: Invalid argument
IO_support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 1 (on)
readahead = 8 (on)
HDIO_GETGEO failed: Invalid argument

shilo · 09-08-2004, 11:05 PM

Yeah, the standard answer to choppy DVD playback is to enable DMA. Unfortunately, DMA seems to be enabled already, assuming that your DVD-ROM is in fact /dev/hdb. Do regular media files that you have saved on your hard drive also have choppy playback?

towarzysz · 09-09-2004, 01:57 AM

Are you using the default vesa video card driver that slack is set up with originally? I had the same problem and solved it by changing xorg.conf to use the driver designed for my particular video card.

slackMeUp · 09-09-2004, 02:11 AM

If your video is setup. (using xv extensions)

Then try turning off DMA on your drive... let it stream. It works in some cases.

noxious · 09-09-2004, 08:30 AM

I'm using an old Armada M700 laptop with ati graphics... an old one at 8mb I think.

The card driver is in the xorg.conf somewhere? I'll check...

How do you turn off dma?

noxious · 09-09-2004, 02:57 PM

I get the impression that my little ati card in the laptop isn't doing what's it's supposed to be doing under Slackware... I checked dmesg in Debian and it shows "ATI Technologies Inc. Rage Mobility P/M AGP 2x Rev 100, Mem.... ,etc."... No mention of an ATI card in Slackware.

What gives? Is this what I need? http://gatos.sourceforge.net/overview.php

What edition of Xfree does Slackware 10.0 have?

Thanks...

shilo · 09-09-2004, 03:11 PM

It doesn't have xfree, it uses xorg. Did you configure X for your card? xorgconfig.

noxious · 09-09-2004, 04:46 PM

No sooner than you posted that, I stumbled onto xorgconfig. Screwed my xorg.conf file up royally at first, but a couple more tweaks and I got it up and running.

I turned the color resolution down from 24 bit to 16 bit and the video has smoothed out in Totem and gxine. Mplayer was giving me trouble, so I s--tcanned it.

My screen is still up at 85khz... pretty high but it looks good - and the color looks as good as 24 bit, as far as I can tell.

Thangew...thangew...

spes_hominis · 09-10-2004, 09:17 PM

Enabling the kernel module optimisations for your particular processor is another performance boost you could try. If you're using KDE, there is a graphical client for configuring them. Otherwise, type

Code:

menuconfig

in a terminal or at the command line.
After enabling the K7 optimisations for my past-it Athlon 1100, DVDs ran smoothly on stock graphics drivers.