[mythtv-users] mythcommflag vs mythtranscode for videos

[Michael T. Dean]

On 01/29/2013 10:36 PM, Peter Bennett (cats22) wrote:
> On 01/29/2013 05:24 PM, Michael T. Dean wrote:
>> On 01/29/2013 04:31 PM, Peter Bennett (cats22) wrote:
>>> I am using mythcommflag and it seems that it actually deletes the seek
>>> table, i.e. existing seek table is removed. This actually works quite
>>> well, the transcoded file is an X264 mks file and seeking works
>>> perfectly with no seek table.
>> Yes, as a matter of fact, we don't support the bitstream format of
>> MKV, so you cannot create a seek table for MKV.  (I'm assuming you
>> mean MKV for Matroska Video, as .mks would be Matroska Subtitle (only)).
>>
>>>    However if I do not run the mythcommflag,
>>> the old seek table is still there, and seeking does not work at all,
>>> trying to go forward or back stays in the same place and pixellates the
>>> screen.
>> Well, since we don't record to MKV, you must be creating the seek
>> table (which should not be there for MKV).  Are you doing that with
>> mythtranscode after you transcode to MKV with some other utility?  If
>> so, we need to fix mythtranscode to forbid creation of seek tables for
>> MKV.
>>
>>> I am not sure why this is so, but it works for me. I thin perhaps x264
>>> mks files do not need a seek table so the mythcommflag is removing it.
>>>
>> Or, really, we need to remove both mythtranscode --buildindex and
>> mythcommflag --rebuild and have only one approach for generating seek
>> tables (likely in mythutil's command interface).
> Sorry - I do mean MKV, not mks. I am transcoding the MPG files to MKV
> X264 (using handbrake), then updating the recorded table with the new
> filename ending in MKV. After that I run mythcommflag --rebuild which
> deletes the seek table entries.

Ah, I see--you mean deleting the seektable entries for the 
pre-transcoded recording MPEG.

>   I suppose I could use a SQL command to
> delete the seek table entries instead. As I mentioned, keeping the old
> seek table entries causes problems with seeking, but deleting them
> solves the problem.

No, you're doing it exactly right.  Using mythcommflag --rebuild to 
remove the old seektable is the best way--regardless of what you've 
transcoded to, since it will do the right thing for whatever video 
type.  I thought you were saying you were getting seektable entries for 
the MKV, and I wanted to know where they were coming from so we could 
fix whatever tool was putting them there.  Thanks for explaining (and 
sorry for the noise).

Mike