[mythtv-users] bad analog recordings from PVR-150

[Alan Marchiori]

On Thu, Jul 9, 2009 at 11:13 AM, John Finlay<finlay at moeraki.com> wrote:
> Alan Marchiori wrote:
>>
>> On Thu, Jul 9, 2009 at 7:08 AM, jedi<jedi at mishnet.org> wrote:
>>
>>>
>>> On Thu, Jul 09, 2009 at 04:14:26PM +1200, Nick Rout wrote:
>>>
>>>>
>>>> On Thu, Jul 9, 2009 at 3:26 PM, Alan Marchiori<alan at alanmarian.com>
>>>> wrote:
>>>>
>>>>>
>>>>> I added a pvr-150 just for the heck of it.  The recording quality is
>>>>> really bad, however.  Almost like there is something wrong with the
>>>>> card/drivers/setup it doesn't seem to synchronize to the video
>>>>> properly.  My old nanalog tv gets a perfect picture from the same
>>>>> source.
>>>>>
>>>>> a short
>>>>> cat /dev/video0 > bad2.mpg
>>>>> is located at http://alamode.mines.edu/~amarchio/bad2.mpg
>>>>>
>>>>> the ivtv syslog entries are:
>>>>> [    6.306228] ivtv:  Start initialization, version 1.4.0
>>>>> [    6.306375] ivtv0: Initializing card #0
>>>>> [    6.306378] ivtv0: Autodetected Hauppauge card (cx23416 based)
>>>>> [    6.311990] ivtv 0000:01:06.0: PCI INT A -> Link[LNKA] -> GSI 17
>>>>> (level, low) -> IRQ 17
>>>>> [    6.361458] ivtv0: Autodetected Hauppauge WinTV PVR-150
>>>>> [    6.456485] cx25840 0-0044: cx25843-23 found @ 0x88 (ivtv i2c driver
>>>>> #0)
>>>>> [    6.458640] tuner 0-0061: chip found @ 0xc2 (ivtv i2c driver #0)
>>>>> [    6.458661] wm8775 0-001b: chip found @ 0x36 (ivtv i2c driver #0)
>>>>> [    6.530379] ivtv0: Registered device video0 for encoder MPG (4096
>>>>> kB)
>>>>> [    6.530414] ivtv0: Registered device video32 for encoder YUV (2048
>>>>> kB)
>>>>> [    6.530447] ivtv0: Registered device vbi0 for encoder VBI (1024 kB)
>>>>> [    6.530512] ivtv0: Registered device video24 for encoder PCM (320
>>>>> kB)
>>>>> [    6.530514] ivtv0: Initialized card #0: Hauppauge WinTV PVR-150
>>>>> [    6.530548] ivtv:  End initialization
>>>>> [   20.572211] ivtv 0000:01:06.0: firmware: requesting
>>>>> v4l-cx2341x-enc.fw
>>>>> [   20.677881] ivtv0: Loaded v4l-cx2341x-enc.fw firmware (376836 bytes)
>>>>> [   20.876207] ivtv0: Encoder revision: 0x02060039
>>>>>
>>>>> any thoughts?
>>>>>
>>>>
>>>> yes your stream appears to be 480x480 pixels. Try 720x480 (I think
>>>> thats the NTSC dimensions, PAL will be 720x576)
>>>>
>>>
>>>   Increasing your recording bitrate might also help. Depending on your
>>> source, you may just have a crap signal to deal with (DirecTV) and need
>>> to be more aggressive with your capture settings.
>>>
>>
>>
>> The source is plain old analog cable tv (ntsc).  I think the signal is
>> reasonably good because my old tv gets a clean picture.
>>
>> I have looked through the ivtv docs quickly and don't see any easy way
>> to change the capture resolution or bit rate.  I assume I will have to
>> play around with v4l2-ctl ?
>>
>
> When I set up my PVR-150 I had to change the Default profile in Setup->TV
> Setup->Recording Profiles->MPEG-2 Encoders(PVR-x50,PVR-500) to get good
> recordings. I changed: the video size to 720x480. I use a bitrate of 4500
> and max bitrate of 6000. I also use an audio bitrate of 384.
>
> Try checking and changing your default profile. The original Default profile
> produced results like yours.


I haven't yet verified that changing this in myth works, but via the
command line by setting 720x480 it worked perfectly.

this prints the capture settings
v4l2-ctl -V

this changes it to 720x480
v4l2-ctl --set-fmt-video=width=720,height=480

and after that capture works perfectly.  I'll also play with the
bitrates but this solves the main problem.

Thanks all!

ps. if someone were to make this the default in myth it might avoid
future issues...