[mythtv] Wrong time of recordings when using PVR 350

[Isaac Richards]

On Friday 01 October 2004 03:09 pm, James Armstrong wrote:
> Jay R. Ashworth wrote:
> >On Fri, Oct 01, 2004 at 09:29:27AM -0400, James Armstrong wrote:
> >>>I have done some more systematic testing, and it looks like the
> >>>problem actually is related to recording, not playback. Recordings
> >>>done with the old driver shows correct time regardless if I play it
> >>>back with the old or new driver, recordings done with the new driver
> >>>shows wrong time on playback with both old and new driver.
> >>>
> >>>The fact that it looks like I'm the only one with this problem makes
> >>>me wonder it might be some other stuff related to my system that
> >>>causes this. The ratio between the wrong and correct time is 0.80, but
> >>>25fps/30fps = 0.83, perhaps the time ratio's closeness to 25/30 is
> >>>just a coincidence, and it's actually not a PAL-NTSC issue?
> >>
> >>I have a similar issue with recording hd content from a pcHDTV card. The
> >>total time is always wrong. Most of the time a 1 hour show shows as 51
> >>minutes when I play it back. I am using myth .16 and ivtv
> >> 0.1.10pre2-ck104m.
>
> Not sure where this belongs, but I think we figured out why a hour hd
> recording is showing as ~51 minutes in myth. With roughly 40 minutes of
> show at 24fps (hd) and 20 minutes of commercials at 30fps (sd) I get
> about 52 minutes if the calculation of the recording length is based on
> the fps (i think 30) reported in the recording. 40mins * (24fps/30fps) +
> 20mins (30fps/30fps) = 52 minutes. I also have problems jumping 30
> seconds ff or rw on these recordings. The time changes by 10 seconds but
> the video is only changing by a second at the most.

It does indeed calculate length assuming a constant frame rate.

Isaac