[mythtv-users] Little gems on MythTV wiki

[Brent Bolin]

On Mon, Feb 22, 2010 at 8:41 AM, Brent Bolin <brent.bolin at gmail.com> wrote:
> On Mon, Feb 22, 2010 at 8:21 AM, Christopher Meredith
> <chmeredith at gmail.com> wrote:
>> On Mon, Feb 22, 2010 at 8:12 AM, Brent Bolin <brent.bolin at gmail.com> wrote:
>>> On Mon, Feb 22, 2010 at 7:44 AM, Christopher Meredith
>>> <chmeredith at gmail.com> wrote:
>>>> On Mon, Feb 22, 2010 at 7:24 AM, Brent Bolin <brent.bolin at gmail.com> wrote:
>>>>> Ran across this info -
>>>>>
>>>>> Did you know you can merge two MPG files together?
>>>>> cat File1 File2 > Merged File-name.
>>>>>
>>>>> Doesn't appear to work.  I have a couple of DVD's that are on two
>>>>> disks.  Currently have them as video.name.disk1.mpg and
>>>>> video.name.disk2
>>>>>
>>>>> So I tested to see what would happen.
>>>>>
>>>>> Here is a snippet of what I see in  mythfrontend.log
>>>>>
>>>>> 2010-02-22 07:10:06.282 [h264 @ 0x40646e0]AVC: nal size 1315803467
>>>>> 2010-02-22 07:10:06.282 [h264 @ 0x40646e0]no frame!
>>>>> 2010-02-22 07:10:06.282 [h264 @ 0x40646e0]AVC: nal size -1686999763
>>>>> 2010-02-22 07:10:06.283 [h264 @ 0x40646e0]no frame!
>>>>> 2010-02-22 07:10:06.283 [h264 @ 0x40646e0]AVC: nal size -645962405
>>>>> 2010-02-22 07:10:06.283 [h264 @ 0x40646e0]no frame!
>>>>> 2010-02-22 07:10:06.283 [h264 @ 0x40646e0]AVC: nal size 1296261589
>>>>> 2010-02-22 07:10:06.283 [h264 @ 0x40646e0]no frame!
>>>>> 2010-02-22 07:10:06.284 [h264 @ 0x40646e0]AVC: nal size -1383481424
>>>>> 2010-02-22 07:10:06.284 [h264 @ 0x40646e0]no frame!
>>>>> 2010-02-22 07:10:06.333 AFD: Opened codec 0xaed1df70, id(H264) type(Video)
>>>>> 2010-02-22 07:10:06.334 AFD: codec AAC has 2 channels
>>>>> 2010-02-22 07:10:06.348 AFD: Opened codec 0xac9e8a90, id(AAC) type(Audio)
>>>>> 2010-02-22 07:10:06.348 AFD: codec AC3 has 2 channels
>>>>> 2010-02-22 07:10:06.350 AFD: Opened codec 0xac9e9010, id(AC3) type(Audio)
>>>>> 2010-02-22 07:10:06.350 AFD Error: Could not find decoder for codec
>>>>> (Unknown Codec ID), ignoring.
>>>>> 2010-02-22 07:10:06.398 AFD: Opened codec 0xacdaad20, id(H264) type(Video)
>>>>> 2010-02-22 07:10:06.398 AFD: codec AAC has 2 channels
>>>>> 2010-02-22 07:10:06.399 AFD: Opened codec 0xacdab2a0, id(AAC) type(Audio)
>>>>> 2010-02-22 07:10:06.399 AFD: codec AC3 has 2 channels
>>>>> 2010-02-22 07:10:06.400 AFD: Opened codec 0xacdab820, id(AC3) type(Audio)
>>>>> 2010-02-22 07:10:06.400 AFD Error: Could not find decoder for codec
>>>>> (Unknown Codec ID), ignoring.
>>>>> 2010-02-22 07:10:06.423 Opening audio device 'spdif'. ch 2(2) sr 48000
>>>>> 2010-02-22 07:10:06.423 Opening ALSA audio device 'iec958:{ AES0 0x02 }'.
>>>>> 2010-02-22 07:10:06.601 Opening audio device 'spdif'. ch 2(2) sr 48000
>>>>> 2010-02-22 07:10:06.601 Opening ALSA audio device 'iec958:{ AES0 0x02 }'.
>>>>> 2010-02-22 07:10:06.667 VideoOutputXv: XVideo Adaptor Name: 'NV17 Video Texture'
>>>>> 2010-02-22 07:10:06.737 OSD Theme Dimensions W: 1280 H: 720
>>>>> 2010-02-22 07:10:07.910 TV: StartPlayer(0, Watching Video, main) -- end ok
>>>>> 2010-02-22 07:10:07.911 New DB connection, total: 3
>>>>> 2010-02-22 07:10:07.912 New DB connection, total: 4
>>>>> YadifDeint: In-Pixformat = 1 Out-Pixformat=1
>>>>> YadifDeint: size changed from 0 x 0 -> 720 x 432
>>>>> YadifDeint: Using existing thread.
>>>>> 2010-02-22 07:10:07.920 OpenGLVideoSync()
>>>>> 2010-02-22 07:10:07.982 Video timing method: SGI OpenGL
>>>>> 2010-02-22 07:10:09.848 NVP(0): Prebuffer wait timed out 10 times.
>>>>> 2010-02-22 07:10:11.731 NVP(0): Prebuffer wait timed out 20 times.
>>>>>
>>>>> The two video files were created using Handbrake with High Profile setting.
>>>>>
>>>>> filetype shows -
>>>>>
>>>>>  file ap*
>>>>> apocalypse.now.disk1.mpg: setgid ISO Media, MPEG v4 system, version 2
>>>>> apocalypse.now.disk2.mpg: setgid ISO Media, MPEG v4 system, version 2
>>>>>
>>>>> So I guess this doesn't work.
>>>>
>>>> Yeah, you can't do that with H264, only MPEG2. To concatenate those
>>>> recordings you have to do:
>>>> mencoder -oac copy -ovc copy -forceidx apocalypse.now.disk1.mpg
>>>> apocalypse.now.disk2.mpg -o apocalypse.now.mpg
>>>>
>>>> Also, you should use either the mp4 or mkv containers for H264
>>>> recordings made with Handbrake. In that case, you could also use
>>>> either mkvmerge or MP4Box to easily concatenate files.
>>>> _______________________________________________
>>>> mythtv-users mailing list
>>>> mythtv-users at mythtv.org
>>>> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>>>>
>>>
>>> Does "Also, you should use either the mp4 or mkv containers for H264"
>>> make a quality difference?
>>
>> None at all. But modern container formats are more efficient and
>> introduce greater possibilities. At least Matroska allows multiple
>> streams, embedded subtitles, chapters, attachments, etc. It can also
>> reduce confusion (such as here) where you're working with data that is
>> not typically found in a .mpg file.
>> _______________________________________________
>> mythtv-users mailing list
>> mythtv-users at mythtv.org
>> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>>
>
> Thanks for your quick reply.  Can you give me the cli syntax to join 2
> mp4 video files together.  There are many arguments for this command.
>

Sorry should have been more clear.  You give three commands or
transcoders to do this

mencoder
mkvmerge
MP4Box

Is mencoder a subset of these or something?

I installed mkvmerge.  mencoder is already installed