[linux] v4l demuxer error: chroma selection failed

[walrus]

Hi all,

I have a TV card which works fine (saa7134), with tvtime for example,
via a freebox through a peritel (on /dev/video0).

I use too a quickcam pro 4000 with vlc, on /dev/video1,
which works fine too :

vlc v4l:// :v4l-vdev="/dev/video1" :v4l-adev="/dev/dsp1" :v4l-norm=3 :v4l-frequency=-1

I want to watch TV (so /dev/video0) with vlc (0.8.4), through the peritel :

vlc v4l:// :v4l-vdev="/dev/video0" :v4l-adev="/dev/dsp" :v4l-norm=3 :v4l-frequency=-1

but it fails with message
v4l demuxer error: chroma selection failed.

Why does it not work ?
What's wrong ?

PS : vlc 0.8.1 core dumps.

Thanks in advance.

[walrus]

In fact, verbose vlc gives more info :
[00000269] main input debug: set input option: v4l-vdev to /dev/video
[00000269] main input debug: set input option: v4l-adev to /dev/dsp
[00000269] main input debug: set input option: v4l-norm to 0
[00000269] main input debug: set input option: v4l-tuner to 1
[00000269] main input debug: waiting for thread completion
[00000269] main input debug: `v4l://' gives access `v4l' demux `' path `'
[00000269] main input debug: creating demux: access='v4l' demux='' path=''
[00000270] main demuxer debug: looking for access_demux module: 1 candidate
[00000270] v4l demuxer debug: V4L device ADS Tech Instant TV (saa7135) 3 channels 0 audios 48 < w < 720 32 < h < 578
[00000270] v4l demuxer debug: invalid width 0
[00000270] v4l demuxer debug: invalid height 0
[00000270] v4l demuxer debug: setting channel Television(0) 1 tuners flags=0x1 type=0x1 norm=0x0
[00000270] v4l demuxer debug: invalid tuner, falling back on tuner 0
[00000270] v4l demuxer debug: will use 720x578
[00000270] v4l demuxer debug: v4l device uses brightness: 32896
[00000270] v4l demuxer debug: v4l device uses colour: 33026
[00000270] v4l demuxer debug: v4l device uses hue: 32896
[00000270] v4l demuxer debug: v4l device uses contrast: 35090
[00000270] v4l demuxer debug: v4l device uses frame size: 624240
[00000270] v4l demuxer debug: v4l device uses chroma: I420
[00000270] v4l demuxer warning: I420 refused
[00000270] v4l demuxer error: chroma selection failed

Why i420 is refused ?
What does it means ?

Thx.

[richti]

I have had the same problem with my MSI TV@nywhere.

I found out you have to use RV32 as chroma, this works fine for me.

Code: Select all

vlc v4l:// :v4l-vdev="/dev/video0" :v4l-adev="/dev/dsp" :v4l-norm=0 :v4l-frequency=196250 :v4l-caching=1200 :v4l-chroma="RV32" :v4l-fps=-1,000000 :v4l-samplerate=44100 :v4l-channel=0 :v4l-tuner=1 :v4l-audio=1 :v4l-stereo :v4l-brightness=-1 :v4l-colour=-1 :v4l-hue=-1 :v4l-contrast=-1 :no-v4l-mjpeg :v4l-decimation=1 :v4l-quality=100 ":sout=#transcode{vcodec=mp4v,vb=1024,acodec=mpga,ab=192,channels=2}:duplicate{dst=std{access=http,mux=asf,url=:8080}}"

note: I got the frequency from KDETV

the only problem at the moment is, that there is no Audio while watching TV with VLC ....
I have sound when I play any file, KDETV / TVTime have sound too.
maybe a problem with the selected audio device, I will try later.

hope that helps

[walrus]

[quote="richti"]I have had the same problem with my MSI TV@nywhere.

I found out you have to use RV32 as chroma, this works fine for me.

Not for me

Thanks anyway.

[Richti]

Did you try the other Chroma formats which VLC provides ?
(anywhere in the source:
I420
I411
I422
YUYV
UYVY
RV24
RV32
I42N
I41N
GRAW
)
?

by the way, I have now sound too, I had to start KDE TV after VLC opend the video device. It seems that KDETV does any magic with my card, so sound works.

Now I can watch the next F1 Race in the garden -- GREAT !

[decebal]

I've got the same problem whit vlc and my webcam I keep getting this message:

v4l demuxer warning: RV24 refused
v4l demuxer error: chroma selection failed

What is strange is that I get v4l demuxer warning: RV24 refused no matter what chroma I select - I tried everything in video imput chroma format box: I420, I411, I422 , etc - but always the same "v4l demuxer warning: RV24 refused" comes up, so I guess the chroma imput values are not passed correctly.

The webcam works ok with other applications (not vlc).

[Guest]

After searching throughout the forums it seems lots of other people are having the same problem and there is no fix yet!

[Chronos]

I have MIS TV@nywhere and chroma RV32 and RV16 works but only for resolution less or equal to 320x240. Larger resolution leads to error "chroma selection failed"

You can print chroma supported by your tv card by executing command v4l-info

[dalam]

ammm so sory. my very bad english

What kernel your are using? Operating system?

Do you compile your kernel or using kernel with operating system?


Oh oh oh sory my englsh.

7135 - is new driver in linux. I find new option in the kernel

Enable Video For linux API 1 compatible Layer

And i see that problem contact with this options...
This option not present in kernel that comes with Fedora Core 4,5. In other operating system - i don't know.

But i'cant try now! but tomorrow

oh haaard engl...

[titioft]

what is solving the Chroma problem is to set the size of the image with :size=320x240 or :size=640x480.

That worked for me!

-titi_oft

[jankarlitos]

Hi,

It's actually a size problem... it took me 2 days to find this out

this is my magic line

Code: Select all

vlc v4l:///dev/video:adev=/dev/dsp:size=704x528:norm=1:frequency=217250

Feel free to change the norm, in my country it's NTSC..... do not use norm:NTSC it doesn't work this way

The size is not random, it must be the size supported by your card, mine (phillips saa7134) is 704x528


Hope it helps



Keywords (for googlers): Phillips saa7134, Phillips saa7130, chroma selection failed