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[Sn!per X]

Hello,
I am using delphi to encode an Audio File to wav:
I used: BASS_Encode_Start(channel, 'output.wav', BASS_ENCODE_PCM or BASS_ENCODE_AUTOFREE, nil, nil);
after that i use:
BASS_ChannelPlay(channel, False); // start the channel playing & encoding

The problem is the encoding will take long time to finish, its like Recording a song,
what i need is faster way, Like Encoding without playing the sample song?

Thanks In Advance

[radio42]

Just create a decoding stream (using the BASS_DECODE flag with BASS_StreamCreateFile) and then call BASS_ChannelGetData in a loop.

[Sn!per X]

Hello,
radio42 thanks for your reply 

Still little Stucked:

type
  TBuf       = array of SmallInt;
var
  Buffer : TBuf;
  Stream : HSTREAM;
begin
   Stream := BASS_StreamCreateFile(False, PChar(FileName), 0, 0, BASS_STREAM_DECODE);
   BASS_Encode_Start(Stream, 'output.wav', BASS_ENCODE_PCM, nil, nil);
   BASS_ChannelGetData(Stream, @Buffer, BASS_DATA_FFT1024);
{what i am missing?}
End;
You mean Like above?
and how to call back BASS_ChannelGetData?

Please give me a sample code

Thanks again

[Ian @ un4seen]

You need to call BASS_ChannelGetData repeatedly until all of the source stream has been processed. The loop could look something like this...

while (BASS_ChannelIsActive(Stream) && BASS_Encode_IsActive(Stream)) { // decoder and encoder are still going
BYTE buf[20000];
BASS_ChannelGetData(Stream, buf, sizeof(buf)); // process some data
}

[Sn!per X]

Thanks Ian 

What you pointed to is worked for me 

Just wondering, what the best Buffer size i should use?
More bigger buffer = Faster, but sometimes the end of the file will be there Much 0 Bytes, so what you suggest?

Thanks again and have a nice day

[AndyMK]

but sometimes the end of the file will be there Much 0 Bytes, so what you suggest?

Before you start your encoding, get the size of the source in bytes. Choose a buffer size and loop through the decoding, updating how much you have decoded. Each loop, check how much you have decoded against the total size of the source and if the amount decoded plus the buffer size is greater than the total, decode the total amount minus the amount already decoded to finish the remainder.

[radio42]

More bigger buffer = Faster

This is not necessarily true and depends on the encoder and if you are encoding a file or a CD track. So a general answer can not be given.
For CD tracks a good number is 235200 bytes - as this is the size of 100 sectors.
For files you might use 128KB or more...you'll notice, that the encoding speed is much more limited by the encoder encoding itself than your buffer size.

[Sn!per X]

Hello,

Finally i used the whole file size as a buffer and looped throught it

Thanks guys for the big help and support