IVTV Cards (PVR 500) corrupt video

[tduffy83]

Fresh install of Mythbuntu 9.10 32 bit.

This bug was introduced in 9.04, 8.10 worked flawlessly.

I have 3 PVR 500 cards, and all 6 tuners do this under 9.04 and 9.10 across multiple machines.

The specific problem is that the video severely corrupts at the tuner/encoder level. I have played back the resultant recordings on other frontends and even windows machines and the video is corrupted. Parts of the show will jump all over the place and the show is just completely unwatchable.

Log files: http://mythbuntu.pastebin.com/f55ef0ce

I would really like this bug to be fixed because I want to use the great new features in 0.22, but I'm stuck using 8.10 until it gets fixed. These encoders/tuners are still extremely popular for those of us who still want to pull down analog cable.

Please let me know if there is anything specific I can do to help. If need be I'll even mail you one of my PVR 500 boards, I am that desperate!

[Mario Limonciello (superm1)]

Is VBI currently enabled? If so, try turning it off. It's been known to
cause these types of issues.

On Tue, Jan 5, 2010 at 19:36, tduffy83 <email address hidden> wrote:

> Public bug reported:
>
> Fresh install of Mythbuntu 9.10 32 bit.
>
> This bug was introduced in 9.04, 8.10 worked flawlessly.
>
> I have 3 PVR 500 cards, and all 6 tuners do this under 9.04 and 9.10
> across multiple machines.
>
> The specific problem is that the video severely corrupts at the
> tuner/encoder level. I have played back the resultant recordings on
> other frontends and even windows machines and the video is corrupted.
> Parts of the show will jump all over the place and the show is just
> completely unwatchable.
>
> Log files: http://mythbuntu.pastebin.com/f55ef0ce
>
> I would really like this bug to be fixed because I want to use the great
> new features in 0.22, but I'm stuck using 8.10 until it gets fixed.
> These encoders/tuners are still extremely popular for those of us who
> still want to pull down analog cable.
>
> Please let me know if there is anything specific I can do to help. If
> need be I'll even mail you one of my PVR 500 boards, I am that
> desperate!
>
> ** Affects: mythbuntu
> Importance: Undecided
> Status: New
>
> --
> IVTV Cards (PVR 500) corrupt video
> https://bugs.launchpad.net/bugs/503643
> You received this bug notification because you are a member of Mythbuntu
> Developers, which is subscribed to Mythbuntu.
>

--
Mario Limonciello
<email address hidden>
Sent from Austin, TX, United States

[tduffy83 (ted4q)]

I set VBI to "none" in mythtv backend setup. Now the frontend will not even let me enable VBI or any CC options.

This has resulted in no change, video is still choppy.

As an aside I was able to get the Tuners to work in mplayer.

ivtv-tune -c 36
mplayer -vo xv -ao alsa -autosync 30 /dev/video0

gives me the same choppy/broken video, 36 is my local ESPN2 station.

Upon further examination I used ivtv-tune to change the frequencies of the channels slightly while watching in mythfrontend and this helped. On some channels I was able to completely fine-tune the corruption out, on some I was able to get it better, but not completely gone. I thought, hey maybe my cable company changed frequency maps to us-cable-hrc or us-cable-irc. Tried both of these maps, and no luck.

Come to think about it I know my cable company didn't change the frequency mappings because I have a 8.10 box sitting next to this 9.10 box set to just plain us-cable and it works flawlessly.

Something changed from 8.10 to 9.04/9.10 either in IVTV or mythbuntu itself. My guess is that it's a problem with how the driver tunes the frequencies as I can help the issue but never actually fix it altogether. My next step is to analyze my channels in the database to compare the 8.10 frequency mappings to the 9.10 mappings. My guess is that they are the same and again this is an issue with the driver.

[tduffy83 (ted4q)]

As an aside, does anyone know how I might use the IVTV drivers that were in use with 8.10 with 9.10? I know IVTV has been added to the kernel so I assume I'd have to compile source, but I'm pretty lost when it comes to actually knowing how to do this.

[tduffy83 (ted4q)]

Still waiting on someone to actually acknowledge this as a bug. I know a lot of people think that analog is dead and that these cards are not important. I think that they are. You can still get analog signals over cable in the US. Most digital channels over QAM are encrypted. For some this is the only way to get some cable channels.

I have been using Ubuntu for years and Mythbuntu recently has been awesome. But when a product stops supporting your hardware you might just have to start looking elsewhere.

Again, I am committed to helping fix this bug. I am not a developer, but I am not a newbie either and can follow instructions well.

[tduffy83 (ted4q)]

I did some digging, and may have found the source of the problem.

When I do a channel scan when adding input sources, then delete all channels from channel editor, then fetch channels from schedules direct, it seems the problem has corrected itself. Not really sure what is causing the fetch function to malfunction in the absence of a channel scan, but this does appear to be a workaround.

Either this or the problem has been corrected in a recent ubuntu/mythbuntu update that I don't know about. I did just do a fresh install of 9.10 and updated it immediately after install and before running setup.

[Mario Limonciello (superm1)]

Hi tduffy83:

It's great to hear that you've solved this problem for yourself. From what I understand, it's more preferable to use data provided by schedules direct over a channel scan anyway (although as you pointed out, analog channel scanning is broken in 0.22).

However, hopefully the analog channel scanner will be sorted out for 0.23.