Thank you for helping to improve Mythbuntu by opening this ticket. The work
required to resolve this ticket is too much considering the complexity of the
issue / rarity of the problem / man power of the Mythbuntu team. With that
being said,
if someone else could write a patch, we will do our best to see that upstream
adopts a fix.
** Changed in: mythtv (Ubuntu)
Status: New => Won't Fix
--
mythfrontend should crop 1920x1088 video to 1920x1080
https://bugs.launchpad.net/bugs/312159
You received this bug notification because you are a member of Mythbuntu
Bug Team, which is subscribed to mythtv in ubuntu.
Status in “mythtv” package in Ubuntu: Won't Fix
Bug description:
Binary package hint: mythtv
The broadcast standard for HDTV in North America (ATSC) is defined as 1920
columns by 1080 rows (lines). However, a limitation of the MPEG-2 video
standard is that a video must be encoded using blocks of 16x16 pixels. 1080 is
not evenly divisible by 16, so the actual broadcast format is 1920x1088 pixels
-- the bottom 8 pixels get cropped off by the playback device. Mythfrontend
doesn't seem to be doing this correctly.
Most TV stations just encode black in the bottom 8 pixels, but some use a gray
bar (my local PBS station, KTCA, currently does this). A black bar usually
isn't noticeable, but the gray bar can be quite annoying (note that this gray
bar can also appear in transcoded video, so a fix to mythtranscode to crop the
video before scaling and re-encoding is also necessary).
Another side-effect is that this can cause video to be scaled awkwardly when
being displayed on a 16:9 display, since the ratio of the raw video is
16:9.06666...
Note that there is (or was) also a 1440x1080/1440x1088 format for 4:3
high-definition video, so any fix should probably just generically apply to any
video with 1088 lines.
I'm not sure what the story is in Europe or other non-ATSC regions, but since
this is a side-effect of a fundamental attribute of MPEG video, the same issue
probably exists there too.
---
[m...@no5][~]$ lsb_release -rd
Description: Ubuntu 8.10
Release: 8.10
[m...@no5][~]$ apt-cache policy mythtv
mythtv:
Installed: (none)
Candidate: 0.21.0+fixes18722-0ubuntu1
Version table:
0.21.0+fixes18722-0ubuntu1 0
500 http://us.archive.ubuntu.com intrepid/multiverse Packages
---
_______________________________________________
Mailing list: https://launchpad.net/~mythbuntu-bugs
Post to : mythbuntu-bugs@lists.launchpad.net
Unsubscribe : https://launchpad.net/~mythbuntu-bugs
More help : https://help.launchpad.net/ListHelp
