<div class="gmail_quote">On Wed, Oct 12, 2011 at 6:05 AM, Dave Sp <span dir="ltr"><<a href="mailto:davespmyth@gmail.com">davespmyth@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="HOEnZb"><div class="h5"><div class="gmail_quote">On Mon, Oct 10, 2011 at 5:11 AM, Dave Sp <span dir="ltr"><<a href="mailto:davespmyth@gmail.com" target="_blank">davespmyth@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div><div class="gmail_quote">On Fri, Oct 7, 2011 at 6:08 PM, James MacKenzie <span dir="ltr"><<a href="mailto:mst3000@newsguy.com" target="_blank">mst3000@newsguy.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<p>Have you tried playing the file on another device?</p>The reason I ask is
that I had an issue with vertical purple lines on playback of mpeg2 on
anything 1280x720 or 1920x1080 at one point. I had to adjust my playback
profile and then everything played fine.<br><br>Not sure it is your problem,
but thought I'd mention it. If you aren't normally playing things in
mpeg2 this might be your issue.<br><hr>
<b>From:</b> Dave Sp <<a href="mailto:davespmyth@gmail.com" target="_blank">davespmyth@gmail.com</a>><br>
<b>Sent:</b> Fri, 7 Oct 2011 16:47:40 -0400 (EDT)<br>
<b>To:</b> Discussion about mythtv <<a href="mailto:mythtv-users@mythtv.org" target="_blank">mythtv-users@mythtv.org</a>><br>
<b>Subject:</b> [mythtv-users] "mythtranscode --mpeg2" and Vertical Purple
Lines<div><div></div><div><br>
<p>
I use "mythtranscode --mpeg2 --honorcutlist ..." from the command line to
create a cut version of a recording.<br><br>When I play the result, vertical
purple lines show up a couple every 50 seconds. Each burst of purple
lines lasts 20 frames, give or take a few.<br>
<br>(If I don't use the "--mpeg2" option, the result has no purple lines, but
it takes a lot longer to generate the file.)<br><br>Any idea what could be
causing this?<br><br>--Dave<br>
</p></div></div></blockquote></div><br></div>The output from "mythtranscode --mpeg ..." has those purple vertical lines when played in mythvideo, mplayer, and even vlc.<br><br>I re-ran "mythtranscode --mpeg ..." with "-v all". It seems the purple lines coincide with the debug lines "Inserting 0 I-Frames after #....".<br>
<br>Is inserting "0" I-frames causing the glitches?<br><font color="#888888"><br>--Dave<br>
</font></blockquote></div><br></div></div>Each time MPEG2fixup::Start had to call InsertFrame, deltaPTS was either 1201 or 1202, and ptsIncrement was 1501. If I prevent calling InsertFrame under those conditions, the end result has no vertical line artifacts every 50 seconds, but then handbrake-cli spits out hundreds of "sync: video time didn't advance" messages and mythvideo complains of lots of A/V sync issues and doesn't show the time properly.<br>
<br>So it seems InsertFrame needs to be called when deltaPTS is either 1201 or 1202 and ptsIncrement is 1501. Is MPEG2fixup::InsertFrame supposed to insert a duplicate of the previous frame, or is it inserting a frame with no data (resulting in those vertical-line artifacts)?<span class="HOEnZb"><font color="#888888"><br>
</font></span></blockquote><div><br>Follow-up: After a recent ffmpeg/libav* package upgrade from <a href="http://debian-multimedia.org">debian-multimedia.org</a>, my "purple vertical lines" issue has disappeared. (I used the same source recording to verify that the issue is gone.) I didn't have to re-compile Myth for this to happen.<br>
<br>I'm not sure (yet) what the external bug was. If I do find out, I'll update this thread (just in case anyone else is curious).<br><br>--Dave<br></div></div>