Mailing List Archive

Poor quality with hauppage PVR500
(Apologies if you've heard this before ... I accidentally sent it to
mythtv-users, I guess some people are on both. Ooops!)

I've set it to tha appropriate standard for Belgium - PAL-B/B1/G - but the
quality's quite poor.

Here are a few short samples.

http://www.youtube.com/watch?v=GBuLCKgn8f8

http://www.youtube.com/watch?v=DgvcxxiR96E

http://www.youtube.com/watch?v=B7Kq3WpMogM

The upload process seems accurate, the clips look pretty much the same as
when I look at them in mplayer or download them to a pc and use media player
classic.

I've noticed the image degrades even worse if I split the output between the
PVR and a TV, but before I run out and buy a signal booster, could it be
something else? Of course I'm a lucky guy, it could be both...

There are numerous settings in v4l2-ctl that I don't really understand:

v4l2-ctl -d 1 -l

User Controls

brightness (int) : min=0 max=255 step=1 default=128
value=128 flags=slider
contrast (int) : min=0 max=127 step=1 default=64
value=64 flags=slider
saturation (int) : min=0 max=127 step=1 default=64
value=64 flags=slider
hue (int) : min=-128 max=127 step=1 default=0
value=0 flags=slider
volume (int) : min=0 max=65535 step=655
default=60928 value=60928 flags=slider
balance (int) : min=0 max=65535 step=655
default=32768 value=32768 flags=slider
bass (int) : min=0 max=65535 step=655
default=32768 value=32768 flags=slider
treble (int) : min=0 max=65535 step=655
default=32768 value=32768 flags=slider
mute (bool) : default=0 value=0

MPEG Encoder Controls

stream_type (menu) : min=0 max=5 default=0 value=0
flags=update
stream_vbi_format (menu) : min=0 max=1 default=0 value=0
audio_sampling_frequency (menu) : min=0 max=2 default=1 value=1
audio_encoding (menu) : min=1 max=1 default=1 value=1
flags=update
audio_layer_ii_bitrate (menu) : min=9 max=13 default=10 value=10
audio_stereo_mode (menu) : min=0 max=3 default=0 value=0
flags=update
audio_stereo_mode_extension (menu) : min=0 max=3 default=0 value=0
flags=inactive
audio_emphasis (menu) : min=0 max=2 default=0 value=0
audio_crc (menu) : min=0 max=1 default=0 value=0
audio_mute (bool) : default=0 value=0
video_encoding (menu) : min=0 max=1 default=1 value=1
flags=readonly
video_aspect (menu) : min=0 max=3 default=1 value=1
video_b_frames (int) : min=0 max=33 step=1 default=2
value=2 flags=update
video_gop_size (int) : min=1 max=34 step=1 default=12
value=12
video_gop_closure (bool) : default=1 value=1
video_bitrate_mode (menu) : min=0 max=1 default=0 value=0
flags=update
video_bitrate (int) : min=0 max=27000000 step=1
default=6000000 value=6000000
video_peak_bitrate (int) : min=0 max=27000000 step=1
default=8000000 value=8000000
video_temporal_decimation (int) : min=0 max=255 step=1 default=0
value=0
video_mute (bool) : default=0 value=0
video_mute_yuv (int) : min=0 max=16777215 step=1
default=32896 value=32896
spatial_filter_mode (menu) : min=0 max=1 default=0 value=0
flags=update
spatial_filter (int) : min=0 max=15 step=1 default=0
value=0 flags=slider
spatial_luma_filter_type (menu) : min=0 max=4 default=1 value=1
spatial_chroma_filter_type (menu) : min=0 max=1 default=1 value=1
temporal_filter_mode (menu) : min=0 max=1 default=0 value=0
flags=update
temporal_filter (int) : min=0 max=31 step=1 default=8
value=8 flags=slider
median_filter_type (menu) : min=0 max=4 default=0 value=0
flags=update
median_luma_filter_minimum (int) : min=0 max=255 step=1 default=0
value=0 flags=inactive slider
median_luma_filter_maximum (int) : min=0 max=255 step=1 default=255
value=255 flags=inactive slider
median_chroma_filter_minimum (int) : min=0 max=255 step=1 default=0
value=0 flags=inactive slider
median_chroma_filter_maximum (int) : min=0 max=255 step=1 default=255
value=255 flags=inactive slider
insert_navigation_packets (bool) : default=0 value=0

Anybody have ideas for what I should adjust? Is there anywhere an
explanation of these terms?
Re: Poor quality with hauppage PVR500 [ In reply to ]
With the risk of being obvious. (I assume this is an analogue card and that

your input is analogue PAL B/G.)



First of all ; I'm pretty sure that problem will not be solved by changing

any of the ioctl() parameters

for the MPEG/MP2 encoding.



1. The looks on the video seems to indicate poor reception. Is the card

tuned to the right frequency (and is the frequency one of the official

channels?) You could for example use "scantv" (in v4l2-tools) to search for

active channels. How do you adjust the frequency ? Via MythTV or directly

via "ivtv-tune" (or by you own program)



2. Are all your identified channels equally bad ?



3. Is there any chance of plugging in an ordinary TV on the same cable and

if so, does this give a "perfect" picture?



4. Are the channels identified by your "real" TV the same channels you are

using?



5. Have you captured the videos by simple doing a cat /dev/video0 >

mymovie.mpg ? (or whatever device you system is using)



6. Have you simply tried another coax cable?



Some answers to the questions above might help to pinpoint your issues, and

I might be able to give some more assistance.



/Johan



(I recently spent some time writing some PVR SW using ivtv so so I'm fairly

up to speed on the interfaces - and I'm pretty convinced your results are

due to either poor reception or bad HW)



On Wed, 2 Dec 2009 12:56:08 +0100, Bloke DownThePub

<blokedownthepub@gmail.com> wrote:

> (Apologies if you've heard this before ... I accidentally sent it to

> mythtv-users, I guess some people are on both. Ooops!)

>

> I've set it to tha appropriate standard for Belgium - PAL-B/B1/G - but

the

> quality's quite poor.

>

> Here are a few short samples.

>

> http://www.youtube.com/watch?v=GBuLCKgn8f8

>

> http://www.youtube.com/watch?v=DgvcxxiR96E

>

> http://www.youtube.com/watch?v=B7Kq3WpMogM

>

> The upload process seems accurate, the clips look pretty much the same as

> when I look at them in mplayer or download them to a pc and use media

> player

> classic.

>

> I've noticed the image degrades even worse if I split the output between

> the

> PVR and a TV, but before I run out and buy a signal booster, could it be

> something else? Of course I'm a lucky guy, it could be both...

>

> There are numerous settings in v4l2-ctl that I don't really understand:

>

> v4l2-ctl -d 1 -l

>

> User Controls

>

> brightness (int) : min=0 max=255 step=1 default=128

> value=128 flags=slider

> contrast (int) : min=0 max=127 step=1 default=64

> value=64 flags=slider

> saturation (int) : min=0 max=127 step=1 default=64

> value=64 flags=slider

> hue (int) : min=-128 max=127 step=1

default=0

> value=0 flags=slider

> volume (int) : min=0 max=65535 step=655

> default=60928 value=60928 flags=slider

> balance (int) : min=0 max=65535 step=655

> default=32768 value=32768 flags=slider

> bass (int) : min=0 max=65535 step=655

> default=32768 value=32768 flags=slider

> treble (int) : min=0 max=65535 step=655

> default=32768 value=32768 flags=slider

> mute (bool) : default=0 value=0

>

> MPEG Encoder Controls

>

> stream_type (menu) : min=0 max=5 default=0 value=0

> flags=update

> stream_vbi_format (menu) : min=0 max=1 default=0 value=0

> audio_sampling_frequency (menu) : min=0 max=2 default=1 value=1

> audio_encoding (menu) : min=1 max=1 default=1 value=1

> flags=update

> audio_layer_ii_bitrate (menu) : min=9 max=13 default=10 value=10

> audio_stereo_mode (menu) : min=0 max=3 default=0 value=0

> flags=update

> audio_stereo_mode_extension (menu) : min=0 max=3 default=0 value=0

> flags=inactive

> audio_emphasis (menu) : min=0 max=2 default=0 value=0

> audio_crc (menu) : min=0 max=1 default=0 value=0

> audio_mute (bool) : default=0 value=0

> video_encoding (menu) : min=0 max=1 default=1 value=1

> flags=readonly

> video_aspect (menu) : min=0 max=3 default=1 value=1

> video_b_frames (int) : min=0 max=33 step=1 default=2

> value=2 flags=update

> video_gop_size (int) : min=1 max=34 step=1 default=12

> value=12

> video_gop_closure (bool) : default=1 value=1

> video_bitrate_mode (menu) : min=0 max=1 default=0 value=0

> flags=update

> video_bitrate (int) : min=0 max=27000000 step=1

> default=6000000 value=6000000

> video_peak_bitrate (int) : min=0 max=27000000 step=1

> default=8000000 value=8000000

> video_temporal_decimation (int) : min=0 max=255 step=1 default=0

> value=0

> video_mute (bool) : default=0 value=0

> video_mute_yuv (int) : min=0 max=16777215 step=1

> default=32896 value=32896

> spatial_filter_mode (menu) : min=0 max=1 default=0 value=0

> flags=update

> spatial_filter (int) : min=0 max=15 step=1 default=0

> value=0 flags=slider

> spatial_luma_filter_type (menu) : min=0 max=4 default=1 value=1

> spatial_chroma_filter_type (menu) : min=0 max=1 default=1 value=1

> temporal_filter_mode (menu) : min=0 max=1 default=0 value=0

> flags=update

> temporal_filter (int) : min=0 max=31 step=1 default=8

> value=8 flags=slider

> median_filter_type (menu) : min=0 max=4 default=0 value=0

> flags=update

> median_luma_filter_minimum (int) : min=0 max=255 step=1 default=0

> value=0 flags=inactive slider

> median_luma_filter_maximum (int) : min=0 max=255 step=1 default=255

> value=255 flags=inactive slider

> median_chroma_filter_minimum (int) : min=0 max=255 step=1 default=0

> value=0 flags=inactive slider

> median_chroma_filter_maximum (int) : min=0 max=255 step=1 default=255

> value=255 flags=inactive slider

> insert_navigation_packets (bool) : default=0 value=0

>

> Anybody have ideas for what I should adjust? Is there anywhere an

> explanation of these terms?

_______________________________________________
ivtv-users mailing list
ivtv-users@ivtvdriver.org
http://ivtvdriver.org/mailman/listinfo/ivtv-users
Re: Poor quality with hauppage PVR500 [ In reply to ]
2009/12/3 Johan Persson <johanp@aditus.nu>

>
> With the risk of being obvious. (I assume this is an analogue card and that
>
> your input is analogue PAL B/G.)
>

v4l2-ctl -d 1 --list-standards
...

index : 6
ID : 0x0000000000000007
Name : PAL-BG
Frame period: 1/25
Frame lines : 625

...

v4l2-ctl -d 1 -s 6
Standard set to 00000007

v4l2-ctl -d 1 -S
Video standard = 0x00000007
PAL-B/B1/G



> 1. The looks on the video seems to indicate poor reception. Is the card
>
> tuned to the right frequency (and is the frequency one of the official
>
> channels?) You could for example use "scantv" (in v4l2-tools) to search for
>
> active channels. How do you adjust the frequency ? Via MythTV or directly
>
> via "ivtv-tune" (or by you own program)
>

Trying to get it working from the command line first. That way I know if
the problem is myth.

I can't get a frequency table because my cable company, voo, are clowns.

However googling suggests the europe-west table, and that's what I use, e.g.

ivtv-tune -d /dev/video1 -t europe-west -c SE12

I've also tried fine-tuning the frequency by going up and down in small
increments from the one that gives some picture using

v4l2-ctl -d 1 -f <freq>

And in all cases it gets worse.

Don't have v4l2-tool. It doesn't appear to be part of ivtv-utils-1.4.0

2. Are all your identified channels equally bad ?
>

Some are a little worse, they're a bit worse on the tv too. Not any I'm
interested in.

3. Is there any chance of plugging in an ordinary TV on the same cable and
>
> if so, does this give a "perfect" picture?
>

There's an old small TV in the den and the big one in the lounge is on the
end of a long coax (hence the splitter I mentioned).

I wouldn't say perfect, but considerably better.


>
> 4. Are the channels identified by your "real" TV the same channels you are
>
> using?
>

I don't understand what you mean. If you're asking if those channels are
visible on the TV, then yes.

However for reasons mentioned above I don't know if the TVs are tuned to the
same frequency. They just show a graphic not the exact number.


>
> 5. Have you captured the videos by simple doing a cat /dev/video0 >
>
> mymovie.mpg ? (or whatever device you system is using)
>

Yes, that's how I created the samples.

>
> 6. Have you simply tried another coax cable?
>

Yes, it was the first thing I tried. No effect. As I mentioned, bypassing
the splitter did help. With it in place I barely see anything.

>
> Some answers to the questions above might help to pinpoint your issues, and
>
> I might be able to give some more assistance.
>
>
>
> /Johan
>
>
>
> (I recently spent some time writing some PVR SW using ivtv so so I'm fairly
>
> up to speed on the interfaces - and I'm pretty convinced your results are
>
> due to either poor reception or bad HW)
>
>
>
>
Re: Poor quality with hauppage PVR500 [ In reply to ]
On Wed, Dec 2, 2009 at 12:56 PM, Bloke DownThePub <blokedownthepub@gmail.com
> wrote:
>
>
> I've set it to tha appropriate standard for Belgium - PAL-B/B1/G - but the
> quality's quite poor.
>
> I've noticed the image degrades even worse if I split the output between
> the PVR and a TV, but before I run out and buy a signal booster, could it be
> something else? Of course I'm a lucky guy, it could be both...
>
>
Hello,

Just FYI: I experienced also poor quality on my initial setup (also in
Belgium ;-), analogue cable, using two splitters, one to split the signal
betweem TV and PC, second splitter to split between PVR350 and PVR500).
Replacing the two spliiters by an amplifier with multiple outputs, and
replacing the coax connectors on the cables used increased the image quality
drastically.
Remark however that my image quality wasn't as worse as your posted samples.