Problem with CMMFCodec

[neel.soft]

hi,
i want to convert .amr file into .wma and .mp3 file. for that i m using CMMFCodec class .

But problem is instance of CMMFCodec is not creating.

Can anybody help me out.

[Sorcery-ltd]

How are you trying to create the codec and on what device?

Encoders to .wma and .mp3 are NOT available on any devices that I'm aware of. Most, but I think not all devices have an AMR encoder that you can access via CMMFCodec. In this case, it's usually easier to record direct to AMR though.

I'm sure I answered an extremely similar question very recently.

If you really need to encode to .wma and .mp3 then you'll need to write/port/buy and license your own codecs.

Sorcery

[neel.soft]

hi,


i m trying to do it with N95. Is conversion supported on specific devices.

I M USING CMMFCodec class .the applecationb crashes (kern exec3 on n95) &
on n76 and n80 it leaves .

what is the exact problem ..

plz can u explain .

thanks in advance

[Sorcery-ltd]

If you try to create a codec of a type that isn't present in the device then you'll get a leave with KErrNotSupported. If you get a Kern-EXEC 3 panic then it's probably because of a BC break in the interface, although there are other possible explanations, like a simple firmware bug.

If the codec isn't present on a device then you certainly can't do conversion with the converter utility either.

Which codec are you trying to create? (you could paste the line of code where you create it with FourCC types).

Sorcery

[neel.soft]

hi,

i m sure


i m showing line of code what i got from forum:

// 1. CMMFCodec* iOCodec = CMMFCodec::NewL(TFourCC(KMMFFourCCCodeAMR), TFourCC(KMMFFourCCCodeMP3));

or

// 2.CMMFCodec* iOCodec = CMMFCodec::NewL(TUid::Uid(0x101FAF67));


what i think is the object of CMMFCodec is the problem?

the object is giving kern-exec3.




Can u plz tell me what other 0x101FAF67 uids are there.

i m not getting the details of these uids . Can u help me out abt these uid?

[Sorcery-ltd]

Hi,

The FourCC codes should work fine, but the ones you are requesting won't work - as I keep trying to say. The only codecs in the device go to or from PCM16, there are no direct conversion codecs! There are also very few codecs that go from PCM16 to another format.

You shouldn't use UIDs for creating codecs, that interface is really only for testing by device manufacturers, or for 3rd party developers who've written their own codec and want to be sure that their application or controller plug-in uses their codec. It's not portable across device manufactuers or even models in some cases otherwise.

Sorcery

[neel.soft]

hi,

thanks for ur information..
what i got now is i Should convert amr to pcm16 and then pcm16 to mp3...

or any other format i would like to convert ....

now is it possible to convert like this:

1. amr->pcm16->mp3

2. amr->pcm16->wma

3. amr->pcm16->aac


i want to convert my recording into all these formats.which one are convertible?

[qxiaoyuan]

if you use CMdaAudioInputStream, u can set DataType to pcm16, so it will skip amr --> pcm16.

and u can do pcm16 --> mp3, pcm16 --> aac, but it will not exist codec pcm16 --> wma.
it seems u need do it by yourself.

[Sorcery-ltd]

Hi,

Are you sure about PCM16 -> MP3? There wasn't an MP3 encoder last time I checked.

Sorcery