sudo v4l2-ctl --all
failed to open /dev/video0: No such file or directory
I've never used ivtv-tune
I can tell you how with dvb-apps and then v4l-utils that replaced it.
Using v4l-utils:
You have to zap/tune to a channel first of course. Which means that you need a channels.conf file of some sort.
[12.1]
VCHANNEL = 12.1
SERVICE_ID = 1
VIDEO_PID = 49
AUDIO_PID = 52
FREQUENCY = 189028615
MODULATION = VSB/8
DELIVERY_SYSTEM = ATSC
[12.2]
VCHANNEL = 12.2
SERVICE_ID = 2
VIDEO_PID = 65
AUDIO_PID = 68
FREQUENCY = 189028615
MODULATION = VSB/8
DELIVERY_SYSTEM = ATSC
[12.3]
VCHANNEL = 12.3
SERVICE_ID = 3
VIDEO_PID = 81
AUDIO_PID = 84
FREQUENCY = 189028615
MODULATION = VSB/8
DELIVERY_SYSTEM = ATSC
#channels conf file
conf="$HOME/.mplayer/dvb_channel.conf"
#zap a channel out of the conf file
dvbv5-zap -ssrc "$conf" 12.1
#Then play/record dvr0
mplayer -vf scale=768:432 -cache 4096 -cache-min 80 /dev/dvb/adapter0/dvr0
locate zap
/usr/bin/azap
/usr/bin/czap
/usr/bin/dvbv5-zap
/usr/bin/dvbzap
/usr/bin/szap
/usr/bin/tzap
Use the right one for your system.
https://www.linuxtv.org/wiki/index.php/Frequency_scan
https://www.linuxtv.org/wiki/index.php/DVBv5_Tools
Or you can make one. Look up the channel frequencies, and make your own conf file manually. If all that you need is channel 3 then that's easy to make.
https://en.wikipedia.org/wiki/Televisio … requencies
https://en.wikipedia.org/wiki/North_Ame … requencies
See man dvbv5-zap
Edit: You may have seen this already
https://www.mythtv.org/wiki/Hauppauge_PVR-250
The PVR-250 and other PVR-xxx cards using the ivtv driver sometimes suffer from a DMA problem. In some cases, this results in the card failing to produce any output until the system is rebooted, even unloading and reloading the driver doesn't clear the error. See ivtvdriver.org for more information about this problem and possible preventative measures.
# dmesg | grep -i 'video\|ivtv'
[ 0.234056] ACPI: Added _OSI(Linux-Dell-Video)
[ 0.288644] pci 0000:00:02.0: Video device with shadowed ROM at [mem 0x000c0000-0x000dffff]
[ 2.430862] Linux video capture interface: v2.00
[ 2.465557] ivtv: Start initialization, version 1.4.3
[ 2.465588] ivtv0: Initializing card 0
[ 2.465590] ivtv0: Autodetected Hauppauge card (cx23416 based)
[ 2.465877] ivtv0: Cannot request encoder memory region.
[ 2.465914] ivtv0: Error -5 on initialization
[ 2.465935] ivtv: probe of 0000:06:00.0 failed with error -5
[ 2.465948] ivtv: End initialization
[ 2.720489] ACPI: Video Device [GFX0] (multi-head: yes rom: no post: no)
[ 2.720597] input: Video Bus as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/LNXVIDEO:00/input/input5
Unsurprising given the age of the hardware, googling on the errors gave outdated advice. Does anyone have some expertise with this type of hardware?
In the past, when I had this working, I could simply have an old VCR hooked up via coax cable, and could digitize the content like this:
% ivtv-tune -c 3
% cat /dev/video0 >capture.mpg
Since the hardware is not initialized, it's no surprise that a simple query errors out:
# v4l2-ctl --all
Failed to open /dev/video0: No such file or directory