On Thu, 2009-11-19 at 14:33 -0800, Tony Ross wrote: > Ben Bronk quoted and wrote: > > >> In order to assist with the start/stop of the recording and > >> positioning of the tape, I need to watch the video stream while it's > >> being saved to disk however, and couldn't figure out how to do that > >> with either mplayer or cat, so I am trying to use MythTV and am > >> meeting with some some success there using the composite video > >> input, but have yet to accomplish the s-video input. > >> > >> MythTV not a trivial task for me to either understand or implement, > >> and your use of the term "struggling" is an understatement in my > >> case. The gui is incredibly non-intuitive, and even after many days > >> of struggling I still have difficulty navigating and understanding > >> the structure, which seems overly complicated for my very simple > >> need of watching the video stream at the same time as it's being > >> recorded to disk. > >> > >> If anyone has a better solution for watching the /dev/video[01] > >> stream while it's being saved to disk I would be very grateful to > >> hear from you, even though it's somewhat off-topic in the ivtv-users > >> list. > > > > cat /dev/video0 | tee <output file> | mplayer - > > > > where <output file> is the file you want to record to. Seems to work > > ok w/ my PVR-500. > > Yes, thank you, of course that works, yet it has similar limitations as > MythTV, albeit without the complexities ... the recording doesn't start > until the video is visible and vice-wersa. > > What I'd like is to be able to do is watch the video stream and start/stop > recording to disk whenever desired. That way I can avoid lengthy dead space > prior to the start of the actual video, and stop it whenever desired, sort > of a real-time stream extraction to disk.
MythTV is always recording to disk when you start to watch TV. What you see is MythTV is slightly delayed, as it's built up somewhat of a buffer on disk. > If I use "mplayer /dev/video0" then I can see what's happening, but am then > unable to cat to a file when desired: > > $ cat /dev/video0 > test.mpg > cat: /dev/video0: Device or resource busy $ mplayer /dev/video32 -demuxer rawvideo -rawvideo w=720:h=480:format=hm12:ntsc will play the YUV (uncompressed video) stream. It is in advance of the MPEG stream by about 2 seconds and is the actual video that the MPEG encoder is about to compress and make available on /dev/video0. /dev/video32 can be read from simultaneously with /dev/video0. (The penalty is of course increased PCI bus usage, and increased CPU to render video.) Regards, Andy > But the PVR-500 has two tuners, so I thought I'd try to use /dev/video1 > after using the same video input as the /dev/video0: > > $ v4l2-ctl -d /dev/video1 --set-input 1 > Video input set to 1 (S-Video 1) > > As reported in dmesg: > > ... > ivtv: ========= NEXT CARD ================== > ivtv1: Autodetected Hauppauge card (cx23416 based) > ivtv1: Unreasonably low latency timer, setting to 64 (was 32) > ivtv1: loaded v4l-cx2341x-enc.fw firmware (376836 bytes) > ivtv1: Encoder revision: 0x02060039 > tuner 1-0061: chip found @ 0xc2 (ivtv i2c driver #1) > cx25840 1-0044: cx25843-23 found @ 0x88 (ivtv i2c driver #1) > cx25840 1-0044: loaded v4l-cx25840.fw firmware (16382 bytes) > wm8775 1-001b: chip found @ 0x36 (ivtv i2c driver #1) > tveeprom 1-0050: Hauppauge model 23552, rev D587, serial# 8897780 > tveeprom 1-0050: tuner model is Samsung TCPN 2121P30A (idx 87, type 70) > tveeprom 1-0050: TV standards NTSC(M) (eeprom 0x08) > tveeprom 1-0050: second tuner model is Philips TEA5768HL FM Radio (idx 101, > type 62) > tveeprom 1-0050: audio processor is CX25843 (idx 37) > tveeprom 1-0050: decoder processor is CX25843 (idx 30) > tveeprom 1-0050: has radio, has no IR remote > ivtv1: Correcting tveeprom data: no radio present on second unit > ivtv1: Autodetected WinTV PVR 500 (unit #2) > ivtv1: Registered device video1 for encoder MPEG (4 MB) > ivtv1: Registered device video33 for encoder YUV (2 MB) > ivtv1: Registered device vbi1 for encoder VBI (1 MB) > ivtv1: Registered device video25 for encoder PCM audio (1 MB) > tuner 1-0061: type set to 70 (Samsung TCPN 2121P30A) > ivtv1: Initialized WinTV PVR 500 (unit #2), card #1 > ivtv: =========== END INIT IVTV =============== > > ... but" mplayer /dev/video1" just displays a black window space while > mplayer reports the statistics, so I'm back where I started ... how to view > the continuous mpeg2 video stream and start/stop recording to disk when > desired. > > > _______________________________________________ > ivtv-users mailing list > [email protected] > http://ivtvdriver.org/mailman/listinfo/ivtv-users > _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
