Florian Kulzer wrote: > On Sat, Sep 29, 2007 at 11:59:04 +0200, Andrea Giuliano wrote: >> Florian Kulzer wrote: >>> On Wed, Sep 26, 2007 at 22:51:30 +0200, Andrea Giuliano wrote: >>> Maybe gnome-mixer does not give you access to the relevant capture >>> controls.
At last, I could get very good recording with arecord and gnome sound recorder reducing the "Capture" control. Damn me if I understand what it is, but it works. I still have the same problem recordin analog video with mjpeg tools, I'm discussing this issue on the mjpeg tools list, and it seems to be a problem which involves mmap. Again, I don't have the slightest idea of what it could be, but it's not a problem of the sound card. I guess we could close this thread. Many thanks. >> I guess I tried every single control, they're even too many, but this >> could a possibility: a control that doesn't affect playback during >> recording, but affects the volume of the recording itself. But which? >>>> Alsa seems correctly configured (at least, sudo alsaconf gives no error). >>> Please post the output of: >>> lsmod | egrep 'snd|intel8x0' >>> amixer | egrep -i '^( .*capture|[^ ])' >> Here they are. Please note that I have both cards installed, but I put on >> the Ensoniq after I got the audio problem, so I'm almost sure the Ensoniq >> has no relevance, at present. > > I agree, let's ignore the presence of the Ensoniq card for now. > > [ snip: list of loaded snd-modules looks OK to me ] > >> Simple mixer control 'Master',0 >> Simple mixer control 'PCM',0 >> Simple mixer control 'Surround',0 >> Simple mixer control 'Surround Jack Mode',0 >> Simple mixer control 'Center',0 >> Simple mixer control 'LFE',0 >> Simple mixer control 'Line',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Playback 25 [81%] [on] Capture [off] >> Front Right: Playback 25 [81%] [on] Capture [off] >> Simple mixer control 'CD',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Playback 0 [0%] [off] Capture [off] >> Front Right: Playback 0 [0%] [off] Capture [off] >> Simple mixer control 'Mic',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Playback 25 [81%] [off] Capture [on] >> Front Right: Playback 25 [81%] [off] Capture [on] > > You probably already tried to reduce the Playback level for the mic (to > make sure it is not some weird feedback effect). > >> Simple mixer control 'Mic Boost (+20dB)',0 > > Check the full output of amixer for the Mic Boost settings. I would put > it at 1.00 dB or even 0.00 dB for a start. > >> Simple mixer control 'Mic Select',0 >> Simple mixer control 'Video',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Capture [off] >> Front Right: Capture [off] >> Simple mixer control 'Phone',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Capture [off] >> Front Right: Capture [off] >> Simple mixer control 'IEC958',0 >> Capture channels: Mono >> Mono: Playback [off] Capture [off] >> Simple mixer control 'IEC958 Capture Monitor',0 >> Simple mixer control 'IEC958 Capture Valid',0 >> Simple mixer control 'IEC958 Playback AC97-SPSA',0 >> Capture channels: Mono >> Simple mixer control 'IEC958 Playback Source',0 >> Simple mixer control 'PC Speaker',0 >> Simple mixer control 'Aux',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Playback 7 [23%] [on] Capture [off] >> Front Right: Playback 7 [23%] [on] Capture [off] >> Simple mixer control 'Mono Output Select',0 >> Simple mixer control 'Capture',0 >> Capture channels: Front Left - Front Right >> Limits: Capture 0 - 15 >> Front Left: Capture 15 [100%] [on] >> Front Right: Capture 15 [100%] [on] >> Simple mixer control 'Mix',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Capture [off] >> Front Right: Capture [off] >> Simple mixer control 'Mix Mono',0 >> Capture exclusive group: 0 >> Capture channels: Front Left - Front Right >> Front Left: Capture [off] >> Front Right: Capture [off] >> Simple mixer control 'Channel Mode',0 >> Simple mixer control 'DAC Clock Source',0 >> Simple mixer control 'External Amplifier',0 > > If you cannot improve the recording quality by reducing the Mic Boost > then you could try to successively turn all capture controls to zero > until you find the one that causes the distorting amplification. I > recommend using "alsamixer" for this; it has a curses-based interface > which gives you a good overview of the playback and capture controls. > You can switch between the two groups of controls by pressing the TAB > key; use CURSOR LEFT/RIGHT to select a control, CURSOR UP/DOWN to change > volume/amplification, and SPACE to toggle capture. > > The names and the interaction of the capture channels are not the same > for all cards, unfortunately. Therefore you are left with trial and > error, but I am pretty sure that one of them will allow you reduce the > amplification to a reasonable value. The names of the controls are > sometimes confusing or at least not really helpful; for example, my > Intel ICH8 card has a control called "Digital" which determines the > amplification of the recordings. If I set it to its maximum value of 30 > dB then I get the same kind of problems that you described in your > earlier mail. > -- Andrea ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
