Red Hat Bugzilla – Bug 19642
"Scope" visualisation mode displayed half-width
Last modified: 2014-03-16 22:16:58 EDT
Whilst an MP3 is playing with the "Scope" visualisation mode selected, the
waveform covers only the left-hand half of the scope area. A (stationary)
flat line is shown in the right-hand half.
Output is to an Opti MAD16 sound card, which is described in /dev/sndstat
MAD16 WSS (82C930) (DUPLEX)
This bug is visible in versions of xmms upto and including 1.2.2, Linux
kernels upto and including 2.2.16-3. Sound output via OSS driver.
Have you tried 1.2.3? I can't reproduce this on the cards I've
I've just had a look at the problem again and have some more info for you:
- With downsampling set to 1:1 (44kHz) in the "MPEG Layer 1/2/3 Player 1.2.3
input plugin, the waveform fills the entire display area, as it is supposed
- With downsampling set to 1:2 (22kHz) only the left-hand half of the display
has a waveform.
- With downsampling set to 1:4 (11kHz) only the left-hand quarter of the
display has a waveform.
I normally use 1:2 (22kHz) for performance reasons.
I've not looked at the source, but from the program behaviour it looks as if
XMMS is providing a bigger buffer for the waveform data than is actually being
filled, leaving the rest as zeros. Yes, the problem is also present in
xmms-1.2.3-2 from RawHide.
Ugly hack added in xmms-1.2.4-7.