[mythtv-users] Question on recording sizes and DVD burning

Tue Jan 21 22:03:02 UTC 2014

On 01/21/2014 04:16 PM, John Finlay wrote:
> On 1/21/2014 8:51 AM, Joseph DeGraw wrote:
>> On 01/21/2014 11:32 AM, John Pilkington wrote:
>>> On 21/01/14 15:21, Joseph DeGraw wrote:
>>>> On 01/21/2014 09:56 AM, John Pilkington wrote:
>>>>> On 21/01/14 14:27, Joseph DeGraw wrote:
>>>>>> On 01/21/2014 09:08 AM, Joseph DeGraw wrote:
>>>>>>> A while ago I upgraded my hardware to include HD recording with a
>>>>>>> ceton
>>>>>>> card and its been great. However, My girlfriend wants to burn
>>>>>>> some of
>>>>>>> her shows to DVD that are 2 hours long. However the size of the
>>>>>>> files
>>>>>>> are like 10 gigs. In mytharchive they can come down to just over 5
>>>>>>> gigs.
>>>>>>> The shows are 1920x? HD from comcast provider. I was thinking that
>>>>>>> reducing them to 720i would be fine to make them smaller to fit on
>>>>>>> DVD.
>>>>>>> This brings up transcoding (which Im looking into right now) and
>>>>>>> profiles.
>>>>>>>
>>>>>>> How do you handle this?
>>>>>>>
>>>>>>> jdegraw
>>>>>> Ok, I have gone into the menu in mytharchive after reading an older
>>>>>> thread and selected a recording profile. I guess my only question
>>>>>> is :
>>>>>> What do the different profiles mean?
>>>>>>
>>>>>> HQ, EP, LP, SD
>>>>>>
>>>>>> I know if I select a SD setting it will not finish and stalls out. I
>>>>>> dont even get an error message. Therefore, Iam trying the LP one
>>>>>> for a
>>>>>> single sided DVD for a 10 gig, 2 hour Lifetime Network movie.
>>>>>>
>>>>>> MythTV .27 / Mythbuntu 12.04 based
>>>>>>
>>>>> With much of the USA now apparently HD only this is clearly
>>>>> getting to
>>>>> be a common problem, and at present I don't think MythArchive handles
>>>>> it well.  The encoder options are defined here: (Fedora build)
>>>>>
>>>>> /usr/share/mythtv/mytharchive/encoder_profiles/ffmpeg_dvd_ntsc.xml
>>>>>
>>>>> and are used within /usr/share/mythtv/mytharchive/scripts/mythburn.py
>>>>>
>>>>> I suspect that the best option would be two-pass specifying the
>>>>> required file size; a fairly minor edit of the HQ option, probably,
>>>>> but requiring some research in the ffmpeg documentation or code.
>>>>>
>>>>> As far as I can see the -b:v value doesn't do much.  The pal-dvd
>>>>> profile, which I use, seems to focus on a q value of 2 as its guiding
>>>>> light.  That isn't specified in the file above.
>>>>>
>>>>> If at present you are getting a 5 GB file the m2vrequantiser option
>>>>> within MythArchive will shrink that quickly with a quality that
>>>>> should
>>>>> be acceptable, but I wouldn't like to rely on it for much higher
>>>>> ratios.
>>>>>
>>>>> HTH
>>>>>
>>>>> John P
>>>>>
>>>>>
>>>>> _______________________________________________
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>>>>> mythtv-users at mythtv.org
>>>>> http://www.mythtv.org/mailman/listinfo/mythtv-users
>>>>>
>>>> Thank you John,
>>>>
>>>> So, It seems that SP is the profile to use on these large HD
>>>> recordings.
>>>> Iam having a problem that it seems to take a rather long time to run
>>>> mytharchive and it seems to be stuck at this point:
>>>>
>>>> *mythffmpeg -threads 6 -v 1 -i
>>>> "/var/lib/mytharchive/temp/work/1/newfile.mpg" -r ntsc -target
>>>> ntsc-dvd
>>>> -b:v 4771k -s 720x480 -acodec copy -copyts -aspect 16:9
>>>> "/var/lib/mytharchive/temp/work/1/newfile2.mpg" -map 0:0 -map 0:1 *
>>>>
>>>> I see that mythmmpeg is still running and taking up ALOT of CPU time.
>>>> Using 'Top' it shows approximately 200 in cpu usage. Seems to just sit
>>>> there for hours. Is this normal? I dont have any error messages in any
>>>> of the logs - mythburn.log, progress.log, kern.log.
>>>>
>>>> What does show in 'top' is that mythmmpeg is still running and
>>>> sometimes
>>>> will spawn another mythmmpeg process.
>>>>
>>>> jdegraw
>>>>
>>> Yes, I think it's normal.   That's one of the problems.  Try
>>>
>>> mythffmpeg  -v verbose -i "infileHD.mpg" -target ntsc-dvd
>>> "outfileSD.mpg"
>>>
>>> on a short recording and see how it goes.  I'm not sure how far my
>>> experience, with h264 recordings, relates to yours, but the -copyts
>>> seemed to be the main problem for me.  ffmpeg -i <filename> should
>>> show what you're dealing with.
>>>
>>>
>>> _______________________________________________
>>> mythtv-users mailing list
>>> mythtv-users at mythtv.org
>>> http://www.mythtv.org/mailman/listinfo/mythtv-users
>>>
>> I will give that a try. Thank you very much for your responses.
>>
>> I did try it earlier on a 1/2 show and it did a good job and burned the
>> cd. Currently, mythffmpeg is still running but at a lower cpu use. But I
>> dont see any disk activity. So, Im going to just let it run till this
>> afternoon. I will also try your suggestion and see what I get.
>>
>> Last time I actually ran out of swap space. So, I bought an additional 4
>> gigs to boost me to 8 gigs. Now that is not a problem anymore :)
>>
>> Nothing in the error logs and mytharchive log still shows the mythffmpeg
>> command line in the log as the last entry. Perhaps I assumed that
>> something was going wrong and killed the process, removed the lock file
>> and cleaned up the temp directory when I should have just let it run
>> instead?
>>
>
> I gave up using mytharchive and use mythffmpeg to transcode my HD
> programs for making DVDs and use a command line like:
>
> mythffmpeg -i <inputfilename>.mpg -map 0:0 -map 0:<1 or 2> 
> -deinterlace -target ntsc-dvd -aspect 16:9 -acodec copy
> <outputfilename>.mpg
>
> The -map 0:<1 or 2> is used to select the best audio channel which
> usually is ac3 5.1. I leave out the -deinterlace if the program is
> 720p. I copy the audio since I see no reason to transcode it to mp2.
> For a 120m movie in 1080i it takes about 140m using my old dual core
> AMD and produces a file which is about 4.1G. The transcode uses about
> 120% CPU according to top.
>
> Then I use dvdauthor and mkisofs to gen the ISO.
>
> John
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>
Ok, Adding to my last post (sorry) I guess the reason it takes soooooo
long for me is that Iam rescaling a 1920x<whatever> recording with a bit
rate of 9000 to a 720 resolution and a bit rate of 4771.

I will just let it run and see how long this thing goes. Probably look
around to see if this thing is broadcast in 720 instead. Then I dont
have to convert the video and it will probably take alot less time.

jdegraw