On Wed, 2008-05-07 at 21:05 -0300, Kevin Blair wrote: > the fallowing is the differnce between when the audio is good and bad > from $ v4l2-ctl --log-status > > --- record.good 2008-05-07 20:51:09.250606270 -0300 > +++ record.bad 2008-05-07 20:53:28.747993406 -0300 > @@ -32,17 +32,16 @@ > ivtv0: Stream: MPEG-2 Program Stream > ivtv0: VBI Format: No VBI > ivtv0: Video: 480x480, 30 fps > - ivtv0: Video: MPEG-2, 4x3, Variable Bitrate, 4000000, Peak 5000000 > + ivtv0: Video: MPEG-2, 4x3, Variable Bitrate, 4500000, Peak 6000000 > ivtv0: Video: GOP Size 15, 2 B-Frames, GOP Closure > ivtv0: Audio: 48 kHz, Layer II, 384 kbps, Stereo, No Emphasis, No CRC > ivtv0: Spatial Filter: Manual, Luma 1D Horizontal, Chroma 1D > Horizontal, 0 > ivtv0: Temporal Filter: Manual, 0 > ivtv0: Median Filter: Off, Luma [0, 255], Chroma [0, 255] > ivtv0: Status flags: 0x00200000 > - ivtv0: Stream encoder MPG: status 0x0118, 2% of 4096 KiB (128 > buffers) in use > + ivtv0: Stream encoder MPG: status 0x0118, 1% of 4096 KiB (128 > buffers) in use > ivtv0: Stream encoder YUV: status 0x0000, 0% of 2048 KiB (64 > buffers) in use > ivtv0: Stream encoder VBI: status 0x0000, 0% of 1040 KiB (61 > buffers) in use > ivtv0: Stream encoder PCM: status 0x0000, 0% of 324 KiB (72 > buffers) in use > - ivtv0: Read MPG/VBI: 1639094208/0 bytes > + ivtv0: Read MPG/VBI: 52113408/0 bytes > ivtv0: ================== END STATUS CARD #0 ================== > > it seems the video vbi and peek go up and the read mpg/vbi goes down, > which would match the issue cause the audio does sound simmiler to audio > recorded at mp2/3 at 32/64kbps rather then a higher rate like 384kbps.
If what you mean is that if increased video bitrate could force lower quality audio, then this explains the poorer quality audio, then I agree. However, I do not know if that's how the encoder actually behaves. > perhaps this may be an issue with mythtv rather then ivtv? mythtv is > version 0.20.2_p14972 Does the mythbackend.log gripe about an ioctl() not working when the tinny audio occurs? If it does, it may be worht hunting down in the MythTV source, what ioctl()s it was trying to set. You could then look at the source for the ivtv driver to see why those ioctl()s may fail. > > this is from audio line in(it is a mce with rca jacks) hooked up to > expressvu sat OK. So this shouldn't be due to audio standard auto-detection by the cx25840. -Andy > > Kevin > > Andy Walls wrote: > > On Wed, 2008-05-07 at 19:06 -0300, Kevin Blair wrote: > >> Hi, > >> > >> im having the bad tinny audio issue on my mythtv system it has only > >> started recently, and is intermittent so some recordings are fine some > >> have bad audio, for live playback majortiy of the time audio is fine > >> only after going in and out and in and out of live tv sevral times did i > >> get the audio tinny, with no pattern its hard to predict or reproduce on > >> command, the source is svid and composite. cat /dev/video0 seems to test > >> out fine, how ever since live tv playback works most of the time i cant > >> say for sure that its working. > >> > >> i am useing gentoo linux and ivtv v1.0.3 i was useing 2.6.24 and i > >> upgraded to 2.6.25 kernel but the problem remains, due to hardware > >> compatibility i cant downgrade kernel. i tried adding tuner=50 to module > >> options with no success. > >> executing v4l2-ctl --set-audio-input 0 ; v4l2-ctl --set-audio-input 1 > >> when i get mythtv audio playback bad the audio goes to normal, which > >> doesnt help fix the problem for recordings. > > > > What is the difference, if any, between the output of > > > > $ v4l2-ctl --log-status > > > > when the audio is good and when the audio is bad on the input same > > source. > > > > Also can you clarify: does this happens with tuner audio only, audio > > line in only, or both? > > > > -Andy > > > >> my tuner is as fallows from lspci -v > >> 05:06.0 Multimedia video controller: Internext Compression Inc iTVC16 > >> (CX23416) MPEG-2 Encoder (rev 01) > >> Subsystem: Hauppauge computer works Inc. WinTV PVR 150 > >> Flags: bus master, medium devsel, latency 64, IRQ 16 > >> Memory at e4000000 (32-bit, prefetchable) [size=64M] > >> Capabilities: [44] Power Management version 2 > >> Kernel driver in use: ivtv > >> Kernel modules: ivtv > >> > >> dmesg output from ivtv being loaded is as fallows: > >> > >> ivtv: Start initialization, version 1.2.0 > >> ivtv0: Initializing card #0 > >> ivtv0: Autodetected Hauppauge card (cx23416 based) > >> ACPI: PCI Interrupt Link [APC1] enabled at IRQ 16 > >> ACPI: PCI Interrupt 0000:05:06.0[A] -> Link [APC1] -> GSI 16 (level, > >> low) -> IRQ 16 > >> ivtv0: Unreasonably low latency timer, setting to 64 (was 32) > >> tveeprom 2-0050: Hauppauge model 26552, rev F068, serial# 10426282 > >> tveeprom 2-0050: tuner model is LG TAPE H001F MK3 (idx 68, type 47) > >> tveeprom 2-0050: TV standards NTSC(M) (eeprom 0x08) > >> tveeprom 2-0050: audio processor is CX25843 (idx 37) > >> tveeprom 2-0050: decoder processor is CX25843 (idx 30) > >> tveeprom 2-0050: has radio, has no IR receiver, has no IR transmitter > >> ivtv0: Autodetected Hauppauge WinTV PVR-150 > >> cx25840 2-0044: cx25843-24 found @ 0x88 (ivtv i2c driver #0) > >> tuner 2-0043: chip found @ 0x86 (ivtv i2c driver #0) > >> tda9887 2-0043: tda988[5/6/7] found > >> tuner 2-0061: chip found @ 0xc2 (ivtv i2c driver #0) > >> wm8775 2-001b: chip found @ 0x36 (ivtv i2c driver #0) > >> tuner-simple 2-0061: type set to 50 (TCL 2002N) > >> ivtv0: Registered device video0 for encoder MPG (4096 kB) > >> ivtv0: Registered device video32 for encoder YUV (2048 kB) > >> ivtv0: Registered device vbi0 for encoder VBI (1024 kB) > >> ivtv0: Registered device video24 for encoder PCM (320 kB) > >> ivtv0: Registered device radio0 for encoder radio > >> ivtv0: Initialized card #0: Hauppauge WinTV PVR-150 > >> ivtv: End initialization > >> > >> and firmware > >> ivtv0: Loaded v4l-cx2341x-enc.fw firmware (376836 bytes) > >> ivtv0: Encoder revision: 0x02060039 > >> cx25840 2-0044: loaded v4l-cx25840.fw firmware (16382 bytes) > >> > >> > >> any suggestions would be much appreciated. > >> > >> Kevin > > > > > > > > _______________________________________________ > > ivtv-users mailing list > > [email protected] > > http://ivtvdriver.org/mailman/listinfo/ivtv-users > > > > _______________________________________________ > ivtv-users mailing list > [email protected] > http://ivtvdriver.org/mailman/listinfo/ivtv-users > _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
