int PcmaDecodeStream::decode( unsigned char *in, short *out )
{
int len = 160;
while ( len-- > 0 )
*out++ = alaw2linear( *in++ );
return 160;
}
bool CDVDAudioCodecPcm::Open(CDVDStreamInfo &hints, CDVDCodecOptions &options)
{
SetDefault();
m_codecID = hints.codec;
m_iSourceChannels = hints.channels;
m_iSourceSampleRate = hints.samplerate;
m_iSourceBitrate = 16;
switch (m_codecID)
{
case CODEC_ID_PCM_ALAW:
{
for (int i = 0; i < 256; i++) table[i] = alaw2linear(i);
break;
}
case CODEC_ID_PCM_MULAW:
{
for (int i = 0; i < 256; i++) table[i] = ulaw2linear(i);
break;
}
default:
{
break;
}
}
// set desired output
m_iOutputChannels = m_iSourceChannels;
return true;
}
void AlawToPcmFilter::AudioChunkIn(AudioChunkRef& inputAudioChunk)
{
m_outputAudioChunk.reset();
if(inputAudioChunk.get() == NULL)
{
return;
}
if(inputAudioChunk->GetNumSamples() == 0)
{
return;
}
AudioChunkDetails outputDetails = *inputAudioChunk->GetDetails();
if(SupportsInputRtpPayloadType(outputDetails.m_rtpPayloadType) == false)
{
return;
}
// Create output buffer
m_outputAudioChunk.reset(new AudioChunk());
outputDetails.m_rtpPayloadType = -1; // Override details that this filter changes
outputDetails.m_encoding = PcmAudio;
int numSamples = inputAudioChunk->GetNumSamples();
outputDetails.m_numBytes = numSamples*2;
short* outputBuffer = (short*)m_outputAudioChunk->CreateBuffer(outputDetails);
char* inputBuffer = (char*)inputAudioChunk->m_pBuffer;
for(int i=0; i<numSamples; i++)
{
outputBuffer[i] = (short)alaw2linear(inputBuffer[i]);
}
}
static av_cold int pcm_decode_init(AVCodecContext * avctx)
{
PCMDecode *s = avctx->priv_data;
int i;
switch(avctx->codec->id) {
case CODEC_ID_PCM_ALAW:
for(i=0;i<256;i++)
s->table[i] = alaw2linear(i);
break;
case CODEC_ID_PCM_MULAW:
for(i=0;i<256;i++)
s->table[i] = ulaw2linear(i);
break;
default:
break;
}
avctx->sample_fmt = avctx->codec->sample_fmts[0];
if (avctx->sample_fmt == SAMPLE_FMT_S32)
avctx->bits_per_raw_sample = av_get_bits_per_sample(avctx->codec->id);
return 0;
}
int wr_g711a_decode(void * state, const char * input, size_t size, short * output)
{
int i = 0;
wr_g711a_decoder_state * s = (wr_g711a_decoder_state * )state;
for (i=0; i < size; i++){
output[i] = (short)alaw2linear((int)(input[i]));
}
return size;
}
static kal_uint16 alawGetSample( const kal_uint16 **pbuf )
{
if( pcm.data_count == 0 ) {
kal_uint16 data = **pbuf;
pcm.data[1] = alaw2linear( (kal_uint8)(data & 0xFF) );
pcm.data[0] = alaw2linear( (kal_uint8)(data >> 8) );
*pbuf = *pbuf + 1;
pcm.data_count = 2;
}
/* Decodes one byte PCMU data to two bytes unsigned linear data */
static int
vocoder_alaw(int fd, u_char *pl, int len)
{
u_int16_t wbuf[2048];
int i = 0;
int wlen = len * sizeof(u_int16_t);
for (i = 0; i < len && (i < sizeof(wbuf) / sizeof(u_int16_t)); i++)
wbuf[i] = alaw2linear(pl[i]);
if (write(fd, wbuf, wlen) < wlen)
return -1;
return wlen;
}
