[Speex-dev] encoding -> decoding doesnt work

[Jürgen Ladstätter]

hi all, 

i'm new to speex and i'm stuck on a problem. I have a buffer that holds 5
seconds of audio data, sampled at 16000 hz and quantitized with 16 bits pcm.
I only want to encode it with speex and then decode it and write it back in
the same buffer.
no compiling errors and no errors during runtime, but from the sample of 5
seconds only a short noise is all I get.

I hope you have any ideas!

kind regards juergen

	SpeexBits bits;
	void *enc_state; 

	speex_bits_init(&bits);
	const SpeexMode *mode;
	mode = speex_lib_get_mode (SPEEX_MODEID_WB);
	enc_state = speex_encoder_init(mode);

	int frame_size = 0;
	speex_encoder_ctl(enc_state,SPEEX_GET_FRAME_SIZE,&frame_size);
	
	int tmp = 16000;
	speex_encoder_ctl(enc_state, SPEEX_SET_SAMPLING_RATE, &tmp);
	tmp = 4;
	speex_encoder_ctl(enc_state, SPEEX_SET_QUALITY, &tmp);
	tmp = 1;
	speex_encoder_ctl(enc_state, SPEEX_SET_VBR, &tmp);
	tmp = 4;
	speex_encoder_ctl(enc_state, SPEEX_SET_VBR_QUALITY, &tmp);
	tmp = 2; 
	speex_encoder_ctl( enc_state, SPEEX_SET_COMPLEXITY, &tmp );
	tmp = 1; 
	speex_encoder_ctl( enc_state, SPEEX_SET_DTX, &tmp );
	tmp = 1; 
	speex_encoder_ctl( enc_state, SPEEX_SET_VAD, &tmp );

	int numBytesEncoded = 0;	
	int amountSamples = defaultfrequency * numchannels * 5; // frequency
is 16000, channels = 1, 5 is for 5 seconds 
	
	unsigned int total = 0;
	char *encoded = NULL;
	for( int j = 0; j < amountSamples/frame_size; j++ )
	{
		// Encode the voice data 
		speex_bits_reset(&bits);
		speex_encode_int(enc_state, (short*)((char*)p_raw1 +
j*frame_size*sizeof(short)), &bits);

		int nBytes = speex_bits_nbytes(&bits);
		char *encodedArray = new char[nBytes];
		int encodedBytes =
speex_bits_write(&bits,encodedArray,nBytes);
		printf("Encoded: %d \t",encodedBytes);
		total += encodedBytes;

		encoded = (char*)realloc( encoded, total );
		memcpy( (encoded+total-encodedBytes), encodedArray,
encodedBytes );
	}
	printf("\n\nTotally: %u\nper Item: %f\n\n", total,
(float)total/(amountSamples/frame_size) );
	speex_bits_destroy(&bits);
	speex_encoder_destroy(enc_state);
	
	// ###########################
	// decoding
	// ###########################
	SpeexBits dec_bits;
	void *dec_state; 

	const SpeexMode *dec_mode;
	dec_mode = speex_lib_get_mode (SPEEX_MODEID_WB);

	speex_bits_init(&dec_bits);
	// speex_nb_mode = 8kHz
	// speex_wb_mode = 16 kHz
	// speex_uwb_mode = 32 kHz
	dec_state = speex_decoder_init(dec_mode);

	frame_size = 0;
	speex_decoder_ctl(dec_state,SPEEX_GET_FRAME_SIZE,&frame_size);
	
	amountSamples = defaultfrequency * numchannels * 5;

	speex_bits_read_from(&dec_bits, encoded, total );
	speex_decode_int( dec_state, &dec_bits, (short*)p_raw1 );
	
	speex_bits_destroy(&dec_bits);
	speex_decoder_destroy(dec_state);