contrib/src/mmedia/sndcpcm.cpp

// --------------------------------------------------------------------------
// Name: sndcpcm.cpp
// Purpose:
// Date: 08/11/1999
// Author: Guilhem Lavaux <lavaux@easynet.fr> (C) 1999, 2000
// CVSID: $Id$
// --------------------------------------------------------------------------
#ifdef __GNUG__
#pragma implementation "sndcpcm.cpp"
#endif

#include "wx/wxprec.h"

#ifndef WX_PRECOMP
    #include "wx/defs.h"
    #include "wx/debug.h"
    #include "wx/log.h"
#endif

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

#include "wx/mmedia/sndbase.h"
#include "wx/mmedia/sndpcm.h"
#include "wx/mmedia/sndcpcm.h"

wxSoundStreamPcm::wxSoundStreamPcm(wxSoundStream& sndio)
        : wxSoundStreamCodec(sndio)
{
    m_function_in = NULL;
    m_function_out = NULL;
    m_prebuffer = NULL;
    m_prebuffer_size = 0;
    m_best_size = 0;
}

wxSoundStreamPcm::~wxSoundStreamPcm()
{
    if (m_prebuffer)
        delete[] m_prebuffer;
}

wxUint32 wxSoundStreamPcm::GetBestSize() const
{
    return m_best_size;
}

// -----------------------------------------------------------------------
// "Converters" definitions/implementations
// -----------------------------------------------------------------------

#define DEFINE_CONV(name, input_type, output_type, convert) \
static void Convert_##name##(const void *buf_in, void *buf_out, wxUint32 len) \
{\
  register input_type src; \
  register const input_type *t_buf_in = (input_type *)buf_in; \
  register output_type *t_buf_out = (output_type *)buf_out; \
\
  while (len > 0) { \
    src = *t_buf_in++; \
    *t_buf_out++ = convert; \
    len -= sizeof(input_type); \
  } \
}

// TODO: define converters for all other formats (32, 24)

DEFINE_CONV(8_8_sign, wxUint8, wxUint8, (src ^ 0x80))

DEFINE_CONV(8_16, wxUint8, wxUint16, (((wxUint16)src) << 8))
DEFINE_CONV(8_16_swap, wxUint8, wxUint16, (src))
DEFINE_CONV(8_16_sign, wxUint8, wxUint16, (((wxUint16)(src ^ 0x80)) << 8))
DEFINE_CONV(8_16_sign_swap, wxUint8, wxUint16, (src ^ 0x80))

DEFINE_CONV(16_8, wxUint16, wxUint8, (wxUint8)(src >> 8))
DEFINE_CONV(16_8_sign, wxUint16, wxUint8, (wxUint8)((src >> 8) ^ 0x80))
DEFINE_CONV(16_swap_8, wxUint16, wxUint8, (wxUint8)(src & 0xff))
DEFINE_CONV(16_swap_8_sign, wxUint16, wxUint8, (wxUint8)((src & 0xff) ^ 0x80))

//DEFINE_CONV(24_8, wxUint32, wxUint8, (wxUint8)(src >> 16))
//DEFINE_CONV(24_8_sig, wxUint32, wxUint8, (wxUint8)((src >> 16) ^ 0x80))

//DEFINE_CONV(32_8, wxUint32, wxUint8, (wxUint8)(src >> 24))

DEFINE_CONV(16_sign, wxUint16, wxUint16, (src ^ 0x8000))
DEFINE_CONV(16_swap, wxUint16, wxUint16, (((src & 0xff) << 8) | ((src >> 8) & 0xff)))
// Problem.
DEFINE_CONV(16_swap_16_sign, wxUint16, wxUint16, ((((src & 0xff) << 8) | ((src >> 8) & 0xff)) ^ 0x80))
// DEFINE_CONV(16_sign_16_swap, wxUint16, wxUint16, ((((src & 0xff) << 8) | ((src >> 8) & 0xff)) ^ 0x8000))
DEFINE_CONV(16_swap_16_sign_swap, wxUint16, wxUint16, (src ^ 0x80))

// -----------------------------------------------------------------------
// Main PCM stream converter table
// -----------------------------------------------------------------------
// Definition
//   XX -> YY
//   XX -> YY sign
//
//   XX swapped -> YY
//   XX swapped -> YY sign
//
//   XX swapped -> YY swapped
//   XX swapped -> YY swapped sign
//
//   XX stereo -> YY mono
//   XX stereo -> YY mono sign
//
//   XX swapped stereo -> YY swapped mono
//   XX swapped stereo -> YY swapped mono sign
//
//   XX swapped stereo -> YY swapped mono
//   XX swapped stereo -> YY swapped mono sign

static wxSoundStreamPcm::ConverterType s_converters[4][3][2] = {
    {
        {
            NULL,
            Convert_8_8_sign                    /* 8 -> 8 sign */
        },
        {
            NULL,
            NULL
        },
        {
            NULL,
            NULL
        }
    },
    {
        {
            Convert_8_16,                       /* 8 -> 16 */
            Convert_8_16_sign                   /* 8 -> 16 sign */
        },
        {
            Convert_8_16_swap,                  /* 8 -> 16 swapped */
            Convert_8_16_sign_swap              /* 8 -> 16 sign swapped */
        },
        {
            NULL,
            NULL
        }
    },
    {
        {
            Convert_16_8,                       /* 16 -> 8 */
            Convert_16_8_sign                   /* 16 -> 8 sign */
        },
        {
            Convert_16_swap_8,                  /* 16 swapped -> 8 */
            Convert_16_swap_8_sign              /* 16 swapped -> 8 sign */
        },
        {
            NULL,
            NULL
        },
    },

    {
        {
            NULL,                               /* 16 -> 16 */
            Convert_16_sign                     /* 16 -> 16 sign */
        },
        {
            Convert_16_swap,                    /* 16 swapped -> 16 */
            Convert_16_swap_16_sign             /* 16 swapped -> 16 sign */
        },
        {
            NULL,
            Convert_16_swap_16_sign_swap        /* 16 swapped -> 16 sign swapped */
        }
    }
};

// This is the buffer size multiplier. It gives the needed size of the output size.
static float s_converters_multip[] = {1, 2, 0.5, 1};

//
// TODO: Read() and Write() aren't really safe. If you give it a buffer which
// is not aligned on 2, you may crash (See converter.def).
//

wxSoundStream& wxSoundStreamPcm::Read(void *buffer, wxUint32 len)
{
    wxUint32 in_bufsize;

    // We must have a multiple of 2
    len &= 0x01;

    if (!m_function_in) {
        m_sndio->Read(buffer, len);
        m_lastcount = m_sndio->GetLastAccess();
        m_snderror = m_sndio->GetError();
        return *this;
    }

    in_bufsize = GetReadSize(len);

    if (len <= m_best_size) {
        m_sndio->Read(m_prebuffer, in_bufsize);
        m_snderror  = m_sndio->GetError();
        if (m_snderror != wxSOUND_NOERROR) {
            m_lastcount = 0;
            return *this;
        }

        m_function_in(m_prebuffer, buffer, m_sndio->GetLastAccess());
    } else {
        char *temp_buffer;

        temp_buffer = new char[in_bufsize];
        m_sndio->Read(temp_buffer, in_bufsize);

        m_snderror =  m_sndio->GetError();
        if (m_snderror != wxSOUND_NOERROR) {
            m_lastcount = 0;
            return *this;
        }

        m_function_in(temp_buffer, buffer, m_sndio->GetLastAccess());

        delete[] temp_buffer;
    }

    m_lastcount = (wxUint32)(m_sndio->GetLastAccess() * m_multiplier_in);

    return *this;
}

wxSoundStream& wxSoundStreamPcm::Write(const void *buffer, wxUint32 len)
{
    wxUint32 out_bufsize;

    if (!m_function_out) {
        m_sndio->Write(buffer, len);
        m_lastcount = m_sndio->GetLastAccess();
        m_snderror  = m_sndio->GetError();
        return *this;
    }

    out_bufsize = GetWriteSize(len);

    if (len <= m_best_size) {
        out_bufsize = GetWriteSize(len);

        m_function_out(buffer, m_prebuffer, len);
        m_sndio->Write(m_prebuffer, out_bufsize);
        m_snderror  = m_sndio->GetError();
        if (m_snderror != wxSOUND_NOERROR) {
            m_lastcount = 0;
            return *this;
        }
    } else {
        char *temp_buffer;

        temp_buffer = new char[out_bufsize];
        m_function_out(buffer, temp_buffer, len);

        m_sndio->Write(temp_buffer, out_bufsize);
        m_snderror =  m_sndio->GetError();
        if (m_snderror != wxSOUND_NOERROR) {
            m_lastcount = 0;
            return *this;
        }

        delete[] temp_buffer;
    }

    m_lastcount = (wxUint32)(m_sndio->GetLastAccess() / m_multiplier_out);

    return *this;
}

bool wxSoundStreamPcm::SetSoundFormat(const wxSoundFormatBase& format)
{
    wxSoundFormatBase *new_format;
    wxSoundFormatPcm *pcm_format, *pcm_format2;

    if (m_sndio->SetSoundFormat(format)) {
        m_function_out = NULL;
        m_function_in = NULL;
        return TRUE;
    }
    if (format.GetType() != wxSOUND_PCM) {
        m_snderror = wxSOUND_INVFRMT;
        return FALSE;
    }
    if (m_sndformat)
        delete m_sndformat;

    new_format = m_sndio->GetSoundFormat().Clone();
    pcm_format = (wxSoundFormatPcm *)&format;
    pcm_format2 = (wxSoundFormatPcm *)new_format;

#if 0
    // ----------------------------------------------------
    // Test whether we need to resample
    if (pcm_format->GetSampleRate() != pcm_format2->GetSampleRate()) {
        wxUint32 src_rate, dst_rate;

        src_rate = pcm_format->GetSampleRate();
        dst_rate = pcm_format2->GetSampleRate();
        m_needResampling = TRUE;
        if (src_rate < dst_rate)
            m_expandSamples = TRUE;
        else
            m_expandSamples = FALSE;
        m_pitch = (src_rate << FLOATBITS) / dst_rate;
    }
#endif
    // ----------------------------------------------------
    // Select table to use:
    //     * 8 bits -> 8 bits
    //     * 16 bits -> 8 bits
    //     * 8 bits -> 16 bits
    //     * 16 bits -> 16 bits

    int table_no, table_no2;
    int i_sign, i_swap;

    switch (pcm_format->GetBPS()) {
        case 8:
            table_no = 0;
            break;
        case 16:
            table_no = 1;
            break;
        default:
            // TODO: Add something here: error, log, ...
            return FALSE;
    }
    switch (pcm_format2->GetBPS()) {
        case 8:
            table_no2 = 0;
            break;
        case 16:
            table_no2 = 1;
            break;
        default:
            // TODO: Add something here: error, log, ...
            return FALSE;
    }

    if (pcm_format2->Signed() != pcm_format->Signed())
        i_sign = 1;
    else
        i_sign = 0;

#define MY_ORDER wxBYTE_ORDER
#if wxBYTE_ORDER == wxLITTLE_ENDIAN
#define OTHER_ORDER wxBIG_ENDIAN
#else
#define OTHER_ORDER wxLITTLE_ENDIAN
#endif

    // --------------------------------------------------------
    // Find the good converter !

    if (pcm_format->GetOrder() == OTHER_ORDER) {
        if (pcm_format->GetOrder() == pcm_format2->GetOrder())
            i_swap = 2;
        else
            i_swap = 1;
    } else {
        if (pcm_format->GetOrder() == pcm_format2->GetOrder())
            i_swap = 0;
        else
            i_swap = 1;
    }

    m_function_out = s_converters[table_no*2+table_no2][i_swap][i_sign];
    m_function_in  = s_converters[table_no2*2+table_no][i_swap][i_sign];
    m_multiplier_out = s_converters_multip[table_no*2+table_no2];
    m_multiplier_in  = s_converters_multip[table_no2*2+table_no2];

    if (m_prebuffer)
        delete[] m_prebuffer;

    // We try to minimize the need of dynamic memory allocation by preallocating a buffer. But
    // to be sure it will be efficient we minimize the best size.
    if (m_multiplier_in < m_multiplier_out) {
        m_prebuffer_size = (wxUint32)(m_sndio->GetBestSize() *
                                      m_multiplier_out);
        m_best_size = (wxUint32)(m_sndio->GetBestSize() *
                                 m_multiplier_in);
    } else {
        m_prebuffer_size = (wxUint32)(m_sndio->GetBestSize() *
                                      m_multiplier_in);
        m_best_size = (wxUint32)(m_sndio->GetBestSize() *
                                 m_multiplier_out);
    }

    m_prebuffer = new char[m_prebuffer_size];

    bool SetSoundFormatReturn;

    SetSoundFormatReturn = m_sndio->SetSoundFormat(*new_format);
    wxASSERT( SetSoundFormatReturn );

    m_sndformat = new_format;
    return TRUE;
}

wxUint32 wxSoundStreamPcm::GetWriteSize(wxUint32 len) const
{
    // For the moment, it is simple but next time it will become more complicated
    // (Resampling)
    return (wxUint32)(len * m_multiplier_out);
}

wxUint32 wxSoundStreamPcm::GetReadSize(wxUint32 len) const
{
    return (wxUint32)(len / m_multiplier_in);
}

// Resampling engine. NOT FINISHED and NOT INCLUDED but this is a first DRAFT.

#if 0

#define FLOATBITS 16
#define INTBITS 16
#define FLOATMASK 0xffff
#define INTMASK 0xffff0000

void ResamplingShrink_##DEPTH##(const void *source, void *destination, wxUint32 len)
{
    wxUint##DEPTH## *source_data, *dest_data;
    wxUint32 pos;

    source_data = (wxUint##DEPTH## *)source;
    dest_data   = (wxUint##DEPTH## *)destination;

    pos = m_saved_pos;
    while (len > 0) {
        // Increment the position in the input buffer
        pos += m_pitch;
        if (pos & INTMASK) {
            pos &= FLOATMASK;

            *dest_data ++ = *source_data;
        }
        len--;
        source_data++;
    }
    m_saved_pos = pos;
}
#endif
Commit	Line	Data
	1	// --------------------------------------------------------------------------
	2	// Name: sndcpcm.cpp
	3	// Purpose:
	4	// Date: 08/11/1999
	5	// Author: Guilhem Lavaux <lavaux@easynet.fr> (C) 1999, 2000
	6	// CVSID: $Id$
	7	// --------------------------------------------------------------------------
	8	#ifdef __GNUG__
	9	#pragma implementation "sndcpcm.cpp"
	10	#endif
	11
	12	#include "wx/wxprec.h"
	13
	14	#ifndef WX_PRECOMP
	15	#include "wx/defs.h"
	16	#include "wx/debug.h"
	17	#include "wx/log.h"
	18	#endif
	19
	20	#ifdef __BORLANDC__
	21	#pragma hdrstop
	22	#endif
	23
	24	#include "wx/mmedia/sndbase.h"
	25	#include "wx/mmedia/sndpcm.h"
	26	#include "wx/mmedia/sndcpcm.h"
	27
	28	wxSoundStreamPcm::wxSoundStreamPcm(wxSoundStream& sndio)
	29	: wxSoundStreamCodec(sndio)
	30	{
	31	m_function_in = NULL;
	32	m_function_out = NULL;
	33	m_prebuffer = NULL;
	34	m_prebuffer_size = 0;
	35	m_best_size = 0;
	36	}
	37
	38	wxSoundStreamPcm::~wxSoundStreamPcm()
	39	{
	40	if (m_prebuffer)
	41	delete[] m_prebuffer;
	42	}
	43
	44	wxUint32 wxSoundStreamPcm::GetBestSize() const
	45	{
	46	return m_best_size;
	47	}
	48
	49	// -----------------------------------------------------------------------
	50	// "Converters" definitions/implementations
	51	// -----------------------------------------------------------------------
	52
	53	#define DEFINE_CONV(name, input_type, output_type, convert) \
	54	static void Convert_##name##(const void buf_in, void buf_out, wxUint32 len) \
	55	{\
	56	register input_type src; \
	57	register const input_type t_buf_in = (input_type )buf_in; \
	58	register output_type t_buf_out = (output_type )buf_out; \
	59	\
	60	while (len > 0) { \
	61	src = *t_buf_in++; \
	62	*t_buf_out++ = convert; \
	63	len -= sizeof(input_type); \
	64	} \
	65	}
	66
	67	// TODO: define converters for all other formats (32, 24)
	68
	69	DEFINE_CONV(8_8_sign, wxUint8, wxUint8, (src ^ 0x80))
	70
	71	DEFINE_CONV(8_16, wxUint8, wxUint16, (((wxUint16)src) << 8))
	72	DEFINE_CONV(8_16_swap, wxUint8, wxUint16, (src))
	73	DEFINE_CONV(8_16_sign, wxUint8, wxUint16, (((wxUint16)(src ^ 0x80)) << 8))
	74	DEFINE_CONV(8_16_sign_swap, wxUint8, wxUint16, (src ^ 0x80))
	75
	76	DEFINE_CONV(16_8, wxUint16, wxUint8, (wxUint8)(src >> 8))
	77	DEFINE_CONV(16_8_sign, wxUint16, wxUint8, (wxUint8)((src >> 8) ^ 0x80))
	78	DEFINE_CONV(16_swap_8, wxUint16, wxUint8, (wxUint8)(src & 0xff))
	79	DEFINE_CONV(16_swap_8_sign, wxUint16, wxUint8, (wxUint8)((src & 0xff) ^ 0x80))
	80
	81	//DEFINE_CONV(24_8, wxUint32, wxUint8, (wxUint8)(src >> 16))
	82	//DEFINE_CONV(24_8_sig, wxUint32, wxUint8, (wxUint8)((src >> 16) ^ 0x80))
	83
	84	//DEFINE_CONV(32_8, wxUint32, wxUint8, (wxUint8)(src >> 24))
	85
	86	DEFINE_CONV(16_sign, wxUint16, wxUint16, (src ^ 0x8000))
	87	DEFINE_CONV(16_swap, wxUint16, wxUint16, (((src & 0xff) << 8) \| ((src >> 8) & 0xff)))
	88	// Problem.
	89	DEFINE_CONV(16_swap_16_sign, wxUint16, wxUint16, ((((src & 0xff) << 8) \| ((src >> 8) & 0xff)) ^ 0x80))
	90	// DEFINE_CONV(16_sign_16_swap, wxUint16, wxUint16, ((((src & 0xff) << 8) \| ((src >> 8) & 0xff)) ^ 0x8000))
	91	DEFINE_CONV(16_swap_16_sign_swap, wxUint16, wxUint16, (src ^ 0x80))
	92
	93	// -----------------------------------------------------------------------
	94	// Main PCM stream converter table
	95	// -----------------------------------------------------------------------
	96	// Definition
	97	// XX -> YY
	98	// XX -> YY sign
	99	//
	100	// XX swapped -> YY
	101	// XX swapped -> YY sign
	102	//
	103	// XX swapped -> YY swapped
	104	// XX swapped -> YY swapped sign
	105	//
	106	// XX stereo -> YY mono
	107	// XX stereo -> YY mono sign
	108	//
	109	// XX swapped stereo -> YY swapped mono
	110	// XX swapped stereo -> YY swapped mono sign
	111	//
	112	// XX swapped stereo -> YY swapped mono
	113	// XX swapped stereo -> YY swapped mono sign
	114
	115	static wxSoundStreamPcm::ConverterType s_converters[4][3][2] = {
	116	{
	117	{
	118	NULL,
	119	Convert_8_8_sign /* 8 -> 8 sign */
	120	},
	121	{
	122	NULL,
	123	NULL
	124	},
	125	{
	126	NULL,
	127	NULL
	128	}
	129	},
	130	{
	131	{
	132	Convert_8_16, /* 8 -> 16 */
	133	Convert_8_16_sign /* 8 -> 16 sign */
	134	},
	135	{
	136	Convert_8_16_swap, /* 8 -> 16 swapped */
	137	Convert_8_16_sign_swap /* 8 -> 16 sign swapped */
	138	},
	139	{
	140	NULL,
	141	NULL
	142	}
	143	},
	144	{
	145	{
	146	Convert_16_8, /* 16 -> 8 */
	147	Convert_16_8_sign /* 16 -> 8 sign */
	148	},
	149	{
	150	Convert_16_swap_8, /* 16 swapped -> 8 */
	151	Convert_16_swap_8_sign /* 16 swapped -> 8 sign */
	152	},
	153	{
	154	NULL,
	155	NULL
	156	},
	157	},
	158
	159	{
	160	{
	161	NULL, /* 16 -> 16 */
	162	Convert_16_sign /* 16 -> 16 sign */
	163	},
	164	{
	165	Convert_16_swap, /* 16 swapped -> 16 */
	166	Convert_16_swap_16_sign /* 16 swapped -> 16 sign */
	167	},
	168	{
	169	NULL,
	170	Convert_16_swap_16_sign_swap /* 16 swapped -> 16 sign swapped */
	171	}
	172	}
	173	};
	174
	175	// This is the buffer size multiplier. It gives the needed size of the output size.
	176	static float s_converters_multip[] = {1, 2, 0.5, 1};
	177
	178	//
	179	// TODO: Read() and Write() aren't really safe. If you give it a buffer which
	180	// is not aligned on 2, you may crash (See converter.def).
	181	//
	182
	183	wxSoundStream& wxSoundStreamPcm::Read(void *buffer, wxUint32 len)
	184	{
	185	wxUint32 in_bufsize;
	186
	187	// We must have a multiple of 2
	188	len &= 0x01;
	189
	190	if (!m_function_in) {
	191	m_sndio->Read(buffer, len);
	192	m_lastcount = m_sndio->GetLastAccess();
	193	m_snderror = m_sndio->GetError();
	194	return *this;
	195	}
	196
	197	in_bufsize = GetReadSize(len);
	198
	199	if (len <= m_best_size) {
	200	m_sndio->Read(m_prebuffer, in_bufsize);
	201	m_snderror = m_sndio->GetError();
	202	if (m_snderror != wxSOUND_NOERROR) {
	203	m_lastcount = 0;
	204	return *this;
	205	}
	206
	207	m_function_in(m_prebuffer, buffer, m_sndio->GetLastAccess());
	208	} else {
	209	char *temp_buffer;
	210
	211	temp_buffer = new char[in_bufsize];
	212	m_sndio->Read(temp_buffer, in_bufsize);
	213
	214	m_snderror = m_sndio->GetError();
	215	if (m_snderror != wxSOUND_NOERROR) {
	216	m_lastcount = 0;
	217	return *this;
	218	}
	219
	220	m_function_in(temp_buffer, buffer, m_sndio->GetLastAccess());
	221
	222	delete[] temp_buffer;
	223	}
	224
	225	m_lastcount = (wxUint32)(m_sndio->GetLastAccess() * m_multiplier_in);
	226
	227	return *this;
	228	}
	229
	230	wxSoundStream& wxSoundStreamPcm::Write(const void *buffer, wxUint32 len)
	231	{
	232	wxUint32 out_bufsize;
	233
	234	if (!m_function_out) {
	235	m_sndio->Write(buffer, len);
	236	m_lastcount = m_sndio->GetLastAccess();
	237	m_snderror = m_sndio->GetError();
	238	return *this;
	239	}
	240
	241	out_bufsize = GetWriteSize(len);
	242
	243	if (len <= m_best_size) {
	244	out_bufsize = GetWriteSize(len);
	245
	246	m_function_out(buffer, m_prebuffer, len);
	247	m_sndio->Write(m_prebuffer, out_bufsize);
	248	m_snderror = m_sndio->GetError();
	249	if (m_snderror != wxSOUND_NOERROR) {
	250	m_lastcount = 0;
	251	return *this;
	252	}
	253	} else {
	254	char *temp_buffer;
	255
	256	temp_buffer = new char[out_bufsize];
	257	m_function_out(buffer, temp_buffer, len);
	258
	259	m_sndio->Write(temp_buffer, out_bufsize);
	260	m_snderror = m_sndio->GetError();
	261	if (m_snderror != wxSOUND_NOERROR) {
	262	m_lastcount = 0;
	263	return *this;
	264	}
	265
	266	delete[] temp_buffer;
	267	}
	268
	269	m_lastcount = (wxUint32)(m_sndio->GetLastAccess() / m_multiplier_out);
	270
	271	return *this;
	272	}
	273
	274	bool wxSoundStreamPcm::SetSoundFormat(const wxSoundFormatBase& format)
	275	{
	276	wxSoundFormatBase *new_format;
	277	wxSoundFormatPcm pcm_format, pcm_format2;
	278
	279	if (m_sndio->SetSoundFormat(format)) {
	280	m_function_out = NULL;
	281	m_function_in = NULL;
	282	return TRUE;
	283	}
	284	if (format.GetType() != wxSOUND_PCM) {
	285	m_snderror = wxSOUND_INVFRMT;
	286	return FALSE;
	287	}
	288	if (m_sndformat)
	289	delete m_sndformat;
	290
	291	new_format = m_sndio->GetSoundFormat().Clone();
	292	pcm_format = (wxSoundFormatPcm *)&format;
	293	pcm_format2 = (wxSoundFormatPcm *)new_format;
	294
	295	#if 0
	296	// ----------------------------------------------------
	297	// Test whether we need to resample
	298	if (pcm_format->GetSampleRate() != pcm_format2->GetSampleRate()) {
	299	wxUint32 src_rate, dst_rate;
	300
	301	src_rate = pcm_format->GetSampleRate();
	302	dst_rate = pcm_format2->GetSampleRate();
	303	m_needResampling = TRUE;
	304	if (src_rate < dst_rate)
	305	m_expandSamples = TRUE;
	306	else
	307	m_expandSamples = FALSE;
	308	m_pitch = (src_rate << FLOATBITS) / dst_rate;
	309	}
	310	#endif
	311	// ----------------------------------------------------
	312	// Select table to use:
	313	// * 8 bits -> 8 bits
	314	// * 16 bits -> 8 bits
	315	// * 8 bits -> 16 bits
	316	// * 16 bits -> 16 bits
	317
	318	int table_no, table_no2;
	319	int i_sign, i_swap;
	320
	321	switch (pcm_format->GetBPS()) {
	322	case 8:
	323	table_no = 0;
	324	break;
	325	case 16:
	326	table_no = 1;
	327	break;
	328	default:
	329	// TODO: Add something here: error, log, ...
	330	return FALSE;
	331	}
	332	switch (pcm_format2->GetBPS()) {
	333	case 8:
	334	table_no2 = 0;
	335	break;
	336	case 16:
	337	table_no2 = 1;
	338	break;
	339	default:
	340	// TODO: Add something here: error, log, ...
	341	return FALSE;
	342	}
	343
	344	if (pcm_format2->Signed() != pcm_format->Signed())
	345	i_sign = 1;
	346	else
	347	i_sign = 0;
	348
	349	#define MY_ORDER wxBYTE_ORDER
	350	#if wxBYTE_ORDER == wxLITTLE_ENDIAN
	351	#define OTHER_ORDER wxBIG_ENDIAN
	352	#else
	353	#define OTHER_ORDER wxLITTLE_ENDIAN
	354	#endif
	355
	356	// --------------------------------------------------------
	357	// Find the good converter !
	358
	359	if (pcm_format->GetOrder() == OTHER_ORDER) {
	360	if (pcm_format->GetOrder() == pcm_format2->GetOrder())
	361	i_swap = 2;
	362	else
	363	i_swap = 1;
	364	} else {
	365	if (pcm_format->GetOrder() == pcm_format2->GetOrder())
	366	i_swap = 0;
	367	else
	368	i_swap = 1;
	369	}
	370
	371	m_function_out = s_converters[table_no*2+table_no2][i_swap][i_sign];
	372	m_function_in = s_converters[table_no2*2+table_no][i_swap][i_sign];
	373	m_multiplier_out = s_converters_multip[table_no*2+table_no2];
	374	m_multiplier_in = s_converters_multip[table_no2*2+table_no2];
	375
	376	if (m_prebuffer)
	377	delete[] m_prebuffer;
	378
	379	// We try to minimize the need of dynamic memory allocation by preallocating a buffer. But
	380	// to be sure it will be efficient we minimize the best size.
	381	if (m_multiplier_in < m_multiplier_out) {
	382	m_prebuffer_size = (wxUint32)(m_sndio->GetBestSize() *
	383	m_multiplier_out);
	384	m_best_size = (wxUint32)(m_sndio->GetBestSize() *
	385	m_multiplier_in);
	386	} else {
	387	m_prebuffer_size = (wxUint32)(m_sndio->GetBestSize() *
	388	m_multiplier_in);
	389	m_best_size = (wxUint32)(m_sndio->GetBestSize() *
	390	m_multiplier_out);
	391	}
	392
	393	m_prebuffer = new char[m_prebuffer_size];
	394
	395	bool SetSoundFormatReturn;
	396
	397	SetSoundFormatReturn = m_sndio->SetSoundFormat(*new_format);
	398	wxASSERT( SetSoundFormatReturn );
	399
	400	m_sndformat = new_format;
	401	return TRUE;
	402	}
	403
	404	wxUint32 wxSoundStreamPcm::GetWriteSize(wxUint32 len) const
	405	{
	406	// For the moment, it is simple but next time it will become more complicated
	407	// (Resampling)
	408	return (wxUint32)(len * m_multiplier_out);
	409	}
	410
	411	wxUint32 wxSoundStreamPcm::GetReadSize(wxUint32 len) const
	412	{
	413	return (wxUint32)(len / m_multiplier_in);
	414	}
	415
	416	// Resampling engine. NOT FINISHED and NOT INCLUDED but this is a first DRAFT.
	417
	418	#if 0
	419
	420	#define FLOATBITS 16
	421	#define INTBITS 16
	422	#define FLOATMASK 0xffff
	423	#define INTMASK 0xffff0000
	424
	425	void ResamplingShrink_##DEPTH##(const void source, void destination, wxUint32 len)
	426	{
	427	wxUint##DEPTH## source_data, dest_data;
	428	wxUint32 pos;
	429
	430	source_data = (wxUint##DEPTH## *)source;
	431	dest_data = (wxUint##DEPTH## *)destination;
	432
	433	pos = m_saved_pos;
	434	while (len > 0) {
	435	// Increment the position in the input buffer
	436	pos += m_pitch;
	437	if (pos & INTMASK) {
	438	pos &= FLOATMASK;
	439
	440	dest_data ++ = source_data;
	441	}
	442	len--;
	443	source_data++;
	444	}
	445	m_saved_pos = pos;
	446	}
	447	#endif