Hi Thomas

Sorry to bother you again but I have created an App that executes the command 
line functions as you suggested.

When I run the App  on the  iPhone simulator, the mp4 file that is produced is 
OK.

When I run it on an iPhone the mp4 file has a green screen with distorted 
images. The sound is OK.

I did a Universal Build using the iFrameExtractor example as a base.

Do you have any suggestions as to what this might be??

Thanks

John


On 21 Oct 2010, at 21:08, Janez Zemva wrote:

> Unfortunately, I don't have the sample anymore, but I can give hints:
> 
> - you need to rename the main() function of ffmpeg.c to something else,
> - you need to provide some other "command-line" parameters, i.e. set
> the argv[] array elements to point to your custom "command line",
> - you need to compile the ffmpeg.c file as C source, set the file type
> in XCode to C source.
> 
> Otherwise, ffmpeg.c, according to my memory, compiles cleanly, without
> any problems. Conversion proceeds at about 2-3 fps though and less on
> older iphones/ipods.
> 
> 2010/10/21 John Gladman <[email protected]>:
>> Hi Thomas
>> 
>> Would you mind sending me a skeleton iPhone APP that uses  ffmpeg.c in this 
>> way??
>> 
>> I have tried using a convert sample provided yesterday and am getting audio 
>> file problems. But I can convert the AVI ok using a command line prompt.
>> 
>> Best Wishes
>> 
>> John Gladman
>> 
>> 
>> On 21 Oct 2010, at 17:42, Thomas Worth wrote:
>> 
>>> On Thu, Oct 21, 2010 at 9:03 AM, Janez Zemva <[email protected]> wrote:
>>> 
>>>> My approach to tackle this problem was to compile the entire ffmpeg.c
>>>> into my app and use it just like a command line utility within from my
>>>> application. The problem with this approach was, that while the use of
>>>> the ffmpeg utility is the same across all platforms. The results of
>>>> conversion certainly aren't (for all tested output formats).
>>>> Generally, the output of the same version ffmpeg, running on the
>>>> iphone, was worse, than the ouput of ffmpeg, running on the desktop
>>>> PC, using the same conversion parameters.
>>>> 
>>>> 2010/10/20 ifrim alexandru <[email protected]>:
>>>>> --- On Wed, 10/20/10, John Gladman <[email protected]> wrote:
>>>>> 
>>>>>> From: John Gladman <[email protected]>
>>>>>> Subject: Re: [libav-user] Using FFmpeg in iPhone Project
>>>>>> To: "Libav* user questions and discussions" <[email protected]>
>>>>>> Date: Wednesday, October 20, 2010, 1:56 PM
>>>>>> Hi
>>>>>> 
>>>>>> What would it cost to provide a sample iPhone APP. I want
>>>>>> to convert a video file from AVI to an MP4 file that will
>>>>>> play on the iPhone.
>>>>>> 
>>>>>> My problem is that I am currently creating an AVI file
>>>>>> within my APP but AVI files won't play on the iPhone. Thats
>>>>>> why I want to be able to convert it to
>>>>>> a format that will play on the iPhone.
>>>>>> 
>>>>>> John G
>>>>>> 
>>>>>> On 20 Oct 2010, at 18:50, Igor R wrote:
>>>>>> 
>>>>>>>> Does anyone have a simple sample iPhone project
>>>>>> that allows video to be converted from one format to
>>>>>> another
>>>>>>> 
>>>>>>> I don't have such a sample project, but I do develop
>>>>>> projects for
>>>>>>> iPhone with ffmpeg libs (libavcodec etc), and it
>>>>>> doesn't differ from
>>>>>>> using ffmpeg on Windows. Actually, we compile on
>>>>>> multiple platforms
>>>>>>> the same portable c++ code, which uses ffmpeg.
>>>>>>> _______________________________________________
>>>>>>> libav-user mailing list
>>>>>>> [email protected]
>>>>>>> https://lists.mplayerhq.hu/mailman/listinfo/libav-user
>>>>>> 
>>>>>> _______________________________________________
>>>>>> libav-user mailing list
>>>>>> [email protected]
>>>>>> https://lists.mplayerhq.hu/mailman/listinfo/libav-user
>>>>>> 
>>>>> 
>>>>> As Igor mentioned the code is the same as on other platforms, but here's
>>>> a sample (from what I remember it was working correctly, I haven't
>>>> used/tested it much though). To convert to mpeg4 you'll need to make some
>>>> changes (it requires some strict parameters from what I recall).
>>>> 
>>> 
>>> There's a lot of assembly code in FFmpeg, which is CPU-specific. I assume
>>> this could cause one platform to behave differently than another, and even
>>> within the same platform depending on the compiler. For example, from what I
>>> understand the Intel C compiler does a better job at optimizing x86 code
>>> than GCC (while sacrificing strict compliance, perhaps), but all of this is
>>> moot if it's already written in assembly. Someone please correct me if I'm
>>> wrong. Thanks.
>>> _______________________________________________
>>> libav-user mailing list
>>> [email protected]
>>> https://lists.mplayerhq.hu/mailman/listinfo/libav-user
>> 
>> 
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