[Clam-devel] Re: [CLAM] Question regarding CLAM::Audio::GetEndTime()

[Xavier Amatriain]

So that is definitely a bug... BeginTime is being incremented in seconds 
while EndTime is output
in milliseconds and expects BeginTime to be also in milliseconds.

The error is in line 128 in MultichannelAudioFileReader:

mDeltaTime = TData <http://www.clam.iua.upf.edu/doc/CLAM-doxygen/namespaceCLAM.html#b9c6321b061069797fcc173f61e8111a>(sizeTmp) / mConfig.GetSourceFile().GetHeader().GetSampleRate();

There is a *1000. missing.

Actually I am seeing that the same error repeats in different places... so I guess the
issue would be easier to fix in the Audio getter. I'll push the discussion to the clam-devel list.



Bad Data wrote:
> This is what I'm doing for every chunk:
>                   std::cout << "EndTime: " << 
> incomingAudioChannels[0].GetEndTime()
>                             << " Size: " << 
> incomingAudioChannels[0].GetSize()
>                             << " BeginTime " << 
> incomingAudioChannels[0].GetBeginTime()
>                             << "\n";
>
>
> And this is what it is outputing:
>
> audioMixer examples # ./FilePlayback_example blue_serge.wav
> EndTime: 23.22 Size: 1024 BeginTime 0
> EndTime: 23.2432 Size: 1024 BeginTime 0.02322
> EndTime: 23.2664 Size: 1024 BeginTime 0.0464399
> EndTime: 23.2896 Size: 1024 BeginTime 0.0696599
>
>
> James
>
>
> */Xavier Amatriain <xamat at iua.upf.edu>/* wrote:
>
>     That is weird indeed but I can't see the bug by looking at the
>     code. It
>     is clear that BeginTime is set incorrectly for the first audio.
>     Can you
>     print both GetSize() and GetBeginTime() for all chunks?
>
>     Bad Data wrote:
>     > I've starting to work with CLAM and have come across something
>     that I
>     > don't understand. I started with the FilePlayback_example.cxx to
>     get a
>     > basic idea how Audio is worked with. I changed the main loop of the
>     > program around to see what can be done with the Audio class, during
>     > one such test I did the following:
>     >
>     > while( reader.Do( incomingAudioChannels ) )
>     > {
>     > count += incomingAudioChannels[0].GetSize();
>     > time += incomingAudioChannels[0].GetDuration();
>     >
>     > for ( int i = 0; i < audioOutputs.Size(); i++ ){
>     > audioOutputs[i].Do( incomingAudioChannels[i] );
>     > }
>     > std::cout << "Durr: " <<
>     > incomingAudioChannels[0].GetEndTime() << "\n"; // I added this line.
>     > }
>     >
>     >
>     > when I compile and run this program the first few lines output to
>     > stdout are:
>     > audioMixer examples # ./FilePlayback_example blue_serge.wav
>     > Durr: 23.22
>     > Durr: 23.2432
>     > Durr: 23.2664
>     > Durr: 23.2896
>     > Durr: 23.3128
>     > Durr: 23.3361
>     > Durr: 23.3593
>     >
>     >
>     > Shouldn't the first line be 0.002322 and aren't the subsequent
>     lines
>     > off by 23.22?
>     > It's my understanding that GetEndTime() returns the end time of the
>     > audio in ms, and that the first chunk is only 1024 samples long.
>     Am I
>     > misunderstanding the correct use?
>     >
>     >
>     > James
>     >
>     >
>     >
>     >
>     >
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