[FFmpeg-user] iPod conversion fail

[Roger Pack]

On 12/20/12, . <peace at aleksandrsolzhenitsyn.net> wrote:
>
> On 12/20/2012 05:32 PM, Roger Pack wrote:
>> On 12/20/12, . <peace at aleksandrsolzhenitsyn.net> wrote:
>>> On 12/20/2012 11:59 AM, Roger Pack wrote:
>>>> On 12/20/12, . <peace at aleksandrsolzhenitsyn.net> wrote:
>>>>> Sorry to bother you folks again but I'm not being too successful
>>>>> lately
>>>>> in converting Youtube videos to be played on my iPod 160G Classic.
>>>>>
>>>>> The problem occurs with videos over 10 minutes- around the 16 minute
>>>>> mark they speed up for a few seconds and run all the way to the end of
>>>>> the video and stop.
>>>> Do they play ok with other players?
>>> On VLC, Totem, ffplay it plays perfectly with no problems.
>>>
>>> Is it just the audio or both audio and video that speed up?
>>>
>>> The video speeds up and the audio mutes.  Typically the problem of
>>> "speeding up" manifests itself this way;
>>>
>>> At around the 18 minute mark or so the video briefly pauses, speeds up
>>> really fast and ends.
>>>
>>> The odd thing is that I've used the same code for quite a few months
>>> with no troubles loading and playing them on my iPod.
>> Maybe try another iPod?
> Not possible- don't have one of know anyone who does.
>>  What about QT player?
> Do you mean Quick Time player?  That's some apple program isn't
> it...part of iTunes?

yes.  or in itunes, that might be good enough.

> The good news is I just converted a file to m4v using HandBrake and it
> played perfectly on the iPod.

does it use libx264? can handbrake output to mp4? what if you convert
the m4v to mp4 using ffmpeg -vcodec copy ... does that still fail?
You may be able to see some clue or other by using ffprobe
-show_frames on the various files, and see if there appears to be any
discrepancies.


> I get stuck on codecs- it's got to be mp4 or nothing at all.  So, when
> someone suggests m4v I scratch my head and say, "what's that? Never
> heard of it.

mp4 is a container "h264" is a codec (I think).