On Sat, 2008-06-28 at 19:07 -0400, Andy Walls wrote:
> On Fri, 2008-06-13 at 09:18 +0200, Levente Novák wrote: 
> > I have the following problem with my Hauppauge PVR-150 (ivtv from kernel
> > 2.6.25) and Composite 1 as input: when a VCR is hooked onto the input
> > and is switched on (but play is not yet started), instead of a static
> > blue screen with the usual VCR OSD text, I see a picture which resembles
> > to a TV station which the frequency is not exactly locked to. In other
> > words, the blue screen with OSD is there, but there are a multitude of
> > thin horizontal coloured lines,
> 
> What color are the lines?  Do they seem to be every other line (i.e. all
> the lines in either the odd or even field)?
> 

The color is mostly red (or reddish), and the positions of the lines
vary with every frame (the lines do not have a static vertical position
but are rolling back and forth and larger darker bands are also
superponating onto these lines). I will send you a 2-seconds capture in
private mail to show it.

> > the picture flickers, and is constantly
> > misaligned horizontally.
> 
> What does
> 
> $ v4l2-ctl --log-status
> 
> show for the card when the blue screen with OSD is displayed?  Does it
> match the video standard your VCR uses? Especially of interest are the
> cx25840 status lines, since that chip does digitization and has
> synchronization circuitry, automatic gain controls, chroma subcarrier
> lock circuitry, etc.
> 


Status Log:

   ivtv0: =================  START STATUS CARD #0  =================
   ivtv0: Version: 1.2.0 Card: Hauppauge WinTV PVR-150
   tveeprom 0-0050: The eeprom says no radio is present, but the tuner type
   tveeprom 0-0050: indicates otherwise. I will assume that radio is present.
   tveeprom 0-0050: Hauppauge model 26589, rev C9A5, serial# 9488398
   tveeprom 0-0050: tuner model is TCL MPE05-2 (idx 105, type 38)
   tveeprom 0-0050: TV standards PAL(B/G) PAL(I) SECAM(L/L') PAL(D/D1/K) 
(eeprom 0x74)
   tveeprom 0-0050: audio processor is CX25843 (idx 37)
   tveeprom 0-0050: decoder processor is CX25843 (idx 30)
   tveeprom 0-0050: has radio, has no IR receiver, has no IR transmitter
   cx25840 0-0044: Video signal:              present
   cx25840 0-0044: Detected format:           PAL-BDGHI
   cx25840 0-0044: Specified standard:        PAL-BDGHI
   cx25840 0-0044: Specified video input:     Composite 3
   cx25840 0-0044: Specified audioclock freq: 48000 Hz
   cx25840 0-0044: Detected audio mode:       forced mode
   cx25840 0-0044: Detected audio standard:   no detected audio standard
   cx25840 0-0044: Audio muted:               no
   cx25840 0-0044: Audio microcontroller:     stopped
   cx25840 0-0044: Configured audio standard: automatic detection
   cx25840 0-0044: Configured audio system:   automatic standard and mode 
detection
   cx25840 0-0044: Specified audio input:     External
   cx25840 0-0044: Preferred audio mode:      stereo
   cx25840 0-0044: Selected 65 MHz format:    autodetect
   cx25840 0-0044: Selected 45 MHz format:    chroma
   tda9887 0-0043: Data bytes: b=0x14 c=0x6e e=0x49
   tuner 0-0061: Tuner mode:      analog TV
   tuner 0-0061: Frequency:       400.00 MHz
   tuner 0-0061: Standard:        0x0000000f
   wm8775 0-001b: Input: 2
   ivtv0: Video Input:  Composite 1
   ivtv0: Audio Input:  Line In 1
   ivtv0: Tuner:  TV
   ivtv0: Stream: MPEG-2 Program Stream
   ivtv0: VBI Format: No VBI
   ivtv0: Video:  720x576, 25 fps
   ivtv0: Video:  MPEG-2, 4x3, Variable Bitrate, 6000000, Peak 8000000
   ivtv0: Video:  GOP Size 12, 2 B-Frames, GOP Closure
   ivtv0: Audio:  48 kHz, Layer II, 224 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, 1% of 8192 KiB (256 buffers) in use
   ivtv0: Stream encoder YUV: status 0x0000, 0% of 4096 KiB (128 buffers) in use
   ivtv0: Stream encoder VBI: status 0x0000, 0% of 2073 KiB (81 buffers) in use
   ivtv0: Stream encoder PCM: status 0x0000, 0% of 643 KiB (143 buffers) in use
   ivtv0: Read MPG/VBI: 4096/0 bytes
   ivtv0: ==================  END STATUS CARD #0  ==================

> 
> 
> > Under Windows with WinTV the image is perfect.
> > 
> > One more observation: after pressing on the VCR's play button, the image
> > becomes good and the recordings are OK, so the said problem seems to
> > affect only the static information screen.
> 
> What about live tv video demodulated by the VCR and sent to the
> composite output of the VCR?
> 

I did not try it yet as it would be difficult to hook the antenna cable
on the VCR in its actual place.

> Have you tried a different compsite video cable?  It might matter if the
> VCR's generated signal for the blue screen and OSD is of marginal
> quality.
> 

Not yet, but I doubt this is the cause. I will try it nevertheless if
nothing else helps.

> I realize the ivtv driver should be able to perform as well as the
> Windows driver, but a cable replacement is still a simple fix if it
> resolves your symptoms.
> 
> 
> 
> > But as this latter has
> > problems, I am not really sure the recordings are OK indeed or I simply
> > fail to see the artefacts.
> 
> What ultimately matters are your perceptions.  If you perceive the
> active playback video looks OK, then you really have no problem.  You
> can ask someone in their teens or early 20's to confirm the video has no
> artifacts beyond the norm for VCRs. (Perceptions of younger people
> should be more sensitive to artifacts, but someone that young might not
> know the "norm" for VCRs due to limited exposure to older technology.)
> 
> VCR video quality isn't that great.  VHS decimates the video to about
> half the number of lines being actually recorded onto the tape. VHS also
> restricts video bandwidth somewhat (~3 MHz) which affects horizontal
> resolution. http://en.wikipedia.org/wiki/VHS
> 

Yes, sure, but waving artefacts are seen on at least the tape I was
recording from. From another tape the picture is OK but I will try from
Windows if it is even better with the WinTV driver.

Thanks for your help!

Levente



_______________________________________________
ivtv-users mailing list
[email protected]
http://ivtvdriver.org/mailman/listinfo/ivtv-users

Reply via email to