utils/wxMMedia/sndmulaw.cpp

   1 #ifdef __GNUG__
   2 #pragma implementation "sndmulaw.h"
   3 #endif
   4
   5 #include "sndsnd.h"
   6 #include "sndfrmt.h"
   7 #include "sndmulaw.h"
   8 #include "adpcm/g72x.h"
   9
  10 wxSoundMulawCodec::wxSoundMulawCodec()
  11   : wxSoundCodec()
  12 {
  13 }
  14
  15 wxSoundMulawCodec::~wxSoundMulawCodec()
  16 {
  17 }
  18
  19 void wxSoundMulawCodec::Decode()
  20 {
  21   int smp;
  22   wxSoundDataFormat pref_frmt;
  23
  24   pref_frmt = GetPreferredFormat(0);
  25   if (m_io_format != pref_frmt)
  26     ChainCodecAfter(pref_frmt);
  27
  28   InitMode(DECODING);
  29
  30   while (!Good()) {
  31       smp = ulaw2linear(m_in_sound->GetChar());
  32 #ifdef USE_BE_MACH
  33       m_out_sound->PutChar((smp & 0xff00) >> 8);
  34       m_out_sound->PutChar(smp & 0xff);
  35 #else
  36       m_out_sound->PutChar(smp & 0xff);
  37       m_out_sound->PutChar((smp & 0xff00) >> 8);
  38 #endif
  39   }
  40 }
  41
  42 void wxSoundMulawCodec::Encode()
  43 {
  44   int smp;
  45   wxSoundDataFormat pref_frmt;
  46
  47   pref_frmt = GetPreferredFormat(0);
  48   if (m_io_format != pref_frmt)
  49     ChainCodecBefore(pref_frmt);
  50
  51   InitMode(ENCODING);
  52
  53   while (!Good()) {
  54 #ifdef USE_BE_MACH
  55       smp = ((unsigned short)m_in_sound->GetChar()) << 8;
  56       smp |= m_in_sound->GetChar() & 0xff;
  57 #else
  58       smp = m_in_sound->GetChar() & 0xff;
  59       smp |= ((unsigned short)m_in_sound->GetChar()) << 8;
  60 #endif
  61       m_out_sound->PutChar(linear2ulaw(smp));
  62   }
  63 }
  64
  65 size_t wxSoundMulawCodec::GetByteRate() const
  66 {
  67   return m_srate;
  68 }
  69
  70 wxSoundDataFormat wxSoundMulawCodec::GetPreferredFormat(int WXUNUSED(no)) const
  71 {
  72   wxSoundDataFormat format;
  73
  74   format.SetCodecNo(WXSOUND_PCM);
  75   format.SetSampleRate(m_srate);
  76   format.SetBps(16);
  77   format.SetChannels(1);
  78   format.SetSign(wxSND_SAMPLE_SIGNED);
  79 #ifdef USE_BE_MACH
  80   format.SetByteOrder(wxSND_SAMPLE_BE);
  81 #else
  82   format.SetByteOrder(wxSND_SAMPLE_LE);
  83 #endif
  84   return format;
  85 }