Moved plc, resample, and mp3 to third_party

git-svn-id: http://svn.pjsip.org/repos/pjproject/branches/split-3rd-party@1175 74dad513-b988-da41-8d7b-12977e46ad98

2 files changed, 846 insertions, 0 deletions

diff --git a/third_party/mp3/BladeMP3EncDLL.h b/third_party/mp3/BladeMP3EncDLL.h
new file mode 100644
index 00000000..2e32b913
--- /dev/null
+++ b/third_party/mp3/BladeMP3EncDLL.h
@@ -0,0 +1,283 @@
+/*
+ * Blade Type of DLL Interface for Lame encoder
+ *
+ * Copyright (c) 1999-2002 A.L. Faber
+ * Based on bladedll.h version 1.0 written by Jukka Poikolainen
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA  02111-1307, USA.
+ */
+
+//#define _BLADEDLL 1
+
+#ifndef ___BLADEDLL_H_INCLUDED___
+#define ___BLADEDLL_H_INCLUDED___
+
+#ifdef __GNUC__
+//#define ATTRIBUTE_PACKED	__attribute__((packed))
+#define ATTRIBUTE_PACKED
+#else
+#define ATTRIBUTE_PACKED
+#pragma pack(push)
+#pragma pack(1)
+#endif
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+/* encoding formats */
+
+#define		BE_CONFIG_MP3			0										
+#define		BE_CONFIG_LAME			256		
+
+/* type definitions */
+
+typedef		unsigned long			HBE_STREAM;
+typedef		HBE_STREAM				*PHBE_STREAM;
+typedef		unsigned long			BE_ERR;
+
+/* error codes */
+
+#define		BE_ERR_SUCCESSFUL					0x00000000
+#define		BE_ERR_INVALID_FORMAT				0x00000001
+#define		BE_ERR_INVALID_FORMAT_PARAMETERS	0x00000002
+#define		BE_ERR_NO_MORE_HANDLES				0x00000003
+#define		BE_ERR_INVALID_HANDLE				0x00000004
+#define		BE_ERR_BUFFER_TOO_SMALL				0x00000005
+
+/* other constants */
+
+#define		BE_MAX_HOMEPAGE			128
+
+/* format specific variables */
+
+#define		BE_MP3_MODE_STEREO		0
+#define		BE_MP3_MODE_JSTEREO		1
+#define		BE_MP3_MODE_DUALCHANNEL	2
+#define		BE_MP3_MODE_MONO		3
+
+
+
+#define		MPEG1	1
+#define		MPEG2	0
+
+#ifdef _BLADEDLL
+#undef FLOAT
+	#include <Windows.h>
+#endif
+
+#define CURRENT_STRUCT_VERSION 1
+#define CURRENT_STRUCT_SIZE sizeof(BE_CONFIG)	// is currently 331 bytes
+
+
+typedef enum
+{
+	VBR_METHOD_NONE			= -1,
+	VBR_METHOD_DEFAULT		=  0,
+	VBR_METHOD_OLD			=  1,
+	VBR_METHOD_NEW			=  2,
+	VBR_METHOD_MTRH			=  3,
+	VBR_METHOD_ABR			=  4
+} VBRMETHOD;
+
+typedef enum 
+{
+	LQP_NOPRESET			=-1,
+
+	// QUALITY PRESETS
+	LQP_NORMAL_QUALITY		= 0,
+	LQP_LOW_QUALITY			= 1,
+	LQP_HIGH_QUALITY		= 2,
+	LQP_VOICE_QUALITY		= 3,
+	LQP_R3MIX				= 4,
+	LQP_VERYHIGH_QUALITY	= 5,
+	LQP_STANDARD			= 6,
+	LQP_FAST_STANDARD		= 7,
+	LQP_EXTREME				= 8,
+	LQP_FAST_EXTREME		= 9,
+	LQP_INSANE				= 10,
+	LQP_ABR					= 11,
+	LQP_CBR					= 12,
+	LQP_MEDIUM				= 13,
+	LQP_FAST_MEDIUM			= 14,
+
+	// NEW PRESET VALUES
+	LQP_PHONE	=1000,
+	LQP_SW		=2000,
+	LQP_AM		=3000,
+	LQP_FM		=4000,
+	LQP_VOICE	=5000,
+	LQP_RADIO	=6000,
+	LQP_TAPE	=7000,
+	LQP_HIFI	=8000,
+	LQP_CD		=9000,
+	LQP_STUDIO	=10000
+
+} LAME_QUALITY_PRESET;
+
+
+
+typedef struct	{
+	unsigned long	dwConfig;			// BE_CONFIG_XXXXX
+								// Currently only BE_CONFIG_MP3 is supported
+	union	{
+
+		struct	{
+
+			unsigned long	dwSampleRate;		// 48000, 44100 and 32000 allowed
+			unsigned char	byMode;			// BE_MP3_MODE_STEREO, BE_MP3_MODE_DUALCHANNEL, BE_MP3_MODE_MONO
+			unsigned short	wBitrate;		// 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256 and 320 allowed
+			int	bPrivate;		
+			int	bCRC;
+			int	bCopyright;
+			int	bOriginal;
+
+			} mp3;					// BE_CONFIG_MP3
+
+			struct
+			{
+			// STRUCTURE INFORMATION
+			unsigned long			dwStructVersion;	
+			unsigned long			dwStructSize;
+
+			// BASIC ENCODER SETTINGS
+			unsigned long			dwSampleRate;		// SAMPLERATE OF INPUT FILE
+			unsigned long			dwReSampleRate;		// DOWNSAMPLERATE, 0=ENCODER DECIDES  
+			long			nMode;				// BE_MP3_MODE_STEREO, BE_MP3_MODE_DUALCHANNEL, BE_MP3_MODE_MONO
+			unsigned long			dwBitrate;			// CBR bitrate, VBR min bitrate
+			unsigned long			dwMaxBitrate;		// CBR ignored, VBR Max bitrate
+			long			nPreset;			// Quality preset, use one of the settings of the LAME_QUALITY_PRESET enum
+			unsigned long			dwMpegVersion;		// FUTURE USE, MPEG-1 OR MPEG-2
+			unsigned long			dwPsyModel;			// FUTURE USE, SET TO 0
+			unsigned long			dwEmphasis;			// FUTURE USE, SET TO 0
+
+			// BIT STREAM SETTINGS
+			int			bPrivate;			// Set Private Bit (TRUE/FALSE)
+			int			bCRC;				// Insert CRC (TRUE/FALSE)
+			int			bCopyright;			// Set Copyright Bit (TRUE/FALSE)
+			int			bOriginal;			// Set Original Bit (TRUE/FALSE)
+			
+			// VBR STUFF
+			int			bWriteVBRHeader;	// WRITE XING VBR HEADER (TRUE/FALSE)
+			int			bEnableVBR;			// USE VBR ENCODING (TRUE/FALSE)
+			int				nVBRQuality;		// VBR QUALITY 0..9
+			unsigned long			dwVbrAbr_bps;		// Use ABR in stead of nVBRQuality
+			VBRMETHOD		nVbrMethod;
+			int			bNoRes;				// Disable Bit resorvoir (TRUE/FALSE)
+
+			// MISC SETTINGS
+			int			bStrictIso;			// Use strict ISO encoding rules (TRUE/FALSE)
+			unsigned short			nQuality;			// Quality Setting, HIGH unsigned char should be NOT LOW byte, otherwhise quality=5
+
+			// FUTURE USE, SET TO 0, align strucutre to 331 bytes
+			unsigned char			btReserved[255-4*sizeof(unsigned long) - sizeof( unsigned short )];
+
+			} LHV1;					// LAME header version 1
+
+		struct	{
+
+			unsigned long	dwSampleRate;
+			unsigned char	byMode;
+			unsigned short	wBitrate;
+			unsigned char	byEncodingMethod;
+
+		} aac;
+
+	} format;
+		
+} BE_CONFIG, *PBE_CONFIG ATTRIBUTE_PACKED;
+
+
+typedef struct	{
+
+	// BladeEnc DLL Version number
+
+	unsigned char	byDLLMajorVersion;
+	unsigned char	byDLLMinorVersion;
+
+	// BladeEnc Engine Version Number
+
+	unsigned char	byMajorVersion;
+	unsigned char	byMinorVersion;
+
+	// DLL Release date
+
+	unsigned char	byDay;
+	unsigned char	byMonth;
+	unsigned short	wYear;
+
+	// BladeEnc	Homepage URL
+
+	char	zHomepage[BE_MAX_HOMEPAGE + 1];	
+
+	unsigned char	byAlphaLevel;
+	unsigned char	byBetaLevel;
+	unsigned char	byMMXEnabled;
+
+	unsigned char	btReserved[125];
+
+
+} BE_VERSION, *PBE_VERSION ATTRIBUTE_PACKED;
+
+#ifndef _BLADEDLL
+
+typedef unsigned long	(*BEINITSTREAM)			(PBE_CONFIG, unsigned long *, unsigned long *, PHBE_STREAM);
+typedef unsigned long	(*BEENCODECHUNK)		(HBE_STREAM, unsigned long, short *, unsigned char *, unsigned long *);
+
+// added for floating point audio  -- DSPguru, jd
+typedef unsigned long	(*BEENCODECHUNKFLOATS16NI)	(HBE_STREAM, unsigned long, float *, float *, unsigned char *, unsigned long *);
+typedef unsigned long	(*BEDEINITSTREAM)			(HBE_STREAM, unsigned char *, unsigned long *);
+typedef unsigned long	(*BECLOSESTREAM)			(HBE_STREAM);
+typedef void	(*BEVERSION)				(PBE_VERSION);
+typedef unsigned long	(*BEWRITEVBRHEADER)			(const char*);
+typedef unsigned long	(*BEWRITEINFOTAG)			(HBE_STREAM, const char * );
+
+#define	TEXT_BEINITSTREAM				"beInitStream"
+#define	TEXT_BEENCODECHUNK				"beEncodeChunk"
+#define	TEXT_BEENCODECHUNKFLOATS16NI	"beEncodeChunkFloatS16NI"
+#define	TEXT_BEDEINITSTREAM				"beDeinitStream"
+#define	TEXT_BECLOSESTREAM				"beCloseStream"
+#define	TEXT_BEVERSION					"beVersion"
+#define	TEXT_BEWRITEVBRHEADER			"beWriteVBRHeader"
+#define	TEXT_BEFLUSHNOGAP				"beFlushNoGap"
+#define	TEXT_BEWRITEINFOTAG				"beWriteInfoTag"
+
+
+#else
+
+__declspec(dllexport) unsigned long	beInitStream(PBE_CONFIG pbeConfig, Punsigned long dwSamples, Punsigned long dwBufferSize, PHBE_STREAM phbeStream);
+__declspec(dllexport) unsigned long	beEncodeChunk(HBE_STREAM hbeStream, unsigned long nSamples, PSHORT pSamples, Punsigned char pOutput, Punsigned long pdwOutput);
+
+// added for floating point audio  -- DSPguru, jd
+__declspec(dllexport) unsigned long	beEncodeChunkFloatS16NI(HBE_STREAM hbeStream, unsigned long nSamples, PFLOAT buffer_l, PFLOAT buffer_r, Punsigned char pOutput, Punsigned long pdwOutput);
+__declspec(dllexport) unsigned long	beDeinitStream(HBE_STREAM hbeStream, Punsigned char pOutput, Punsigned long pdwOutput);
+__declspec(dllexport) unsigned long	beCloseStream(HBE_STREAM hbeStream);
+__declspec(dllexport) VOID		beVersion(PBE_VERSION pbeVersion);
+__declspec(dllexport) unsigned long	beWriteVBRHeader(LPCSTR lpszFileName);
+__declspec(dllexport) unsigned long	beFlushNoGap(HBE_STREAM hbeStream, Punsigned char pOutput, Punsigned long pdwOutput);
+__declspec(dllexport) unsigned long	beWriteInfoTag( HBE_STREAM hbeStream, LPCSTR lpszFileName );
+
+#endif
+
+#ifndef __GNUC__
+#pragma pack(pop)
+#endif
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif
diff --git a/third_party/mp3/mp3_writer.c b/third_party/mp3/mp3_writer.c
new file mode 100644
index 00000000..98a0da29
--- /dev/null
+++ b/third_party/mp3/mp3_writer.c
@@ -0,0 +1,563 @@
+/* $Id$ */
+/* 
+ * Copyright (C) 2003-2007 Benny Prijono <benny@prijono.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
+ */
+
+/*
+ * Contributed by:
+ *  Toni < buldozer at aufbix dot org >
+ */
+#include <pjmedia/mp3_port.h>
+#include <pjmedia/errno.h>
+#include <pj/assert.h>
+#include <pj/file_access.h>
+#include <pj/file_io.h>
+#include <pj/log.h>
+#include <pj/pool.h>
+#include <pj/string.h>
+#include <pj/unicode.h>
+
+
+/* Include BladeDLL declarations */
+#include "BladeMP3EncDLL.h"
+
+
+#define THIS_FILE	    "mp3_writer.c"
+#define SIGNATURE	    PJMEDIA_PORT_SIGNATURE('F', 'W', 'M', '3')
+#define BYTES_PER_SAMPLE    2
+
+static struct BladeDLL
+{
+    void		*hModule;
+    int			 refCount;
+    BEINITSTREAM	 beInitStream;
+    BEENCODECHUNK	 beEncodeChunk;
+    BEDEINITSTREAM	 beDeinitStream;
+    BECLOSESTREAM	 beCloseStream;
+    BEVERSION		 beVersion;
+    BEWRITEVBRHEADER	 beWriteVBRHeader;
+    BEWRITEINFOTAG	 beWriteInfoTag;
+} BladeDLL;
+
+
+struct mp3_file_port
+{
+    pjmedia_port    base;
+    pj_size_t	    total;
+    pj_oshandle_t   fd;
+    pj_size_t	    cb_size;
+    pj_status_t	   (*cb)(pjmedia_port*, void*);
+
+    unsigned	    silence_duration;
+
+    pj_str_t			mp3_filename;
+    pjmedia_mp3_encoder_option  mp3_option;
+    unsigned		        mp3_samples_per_frame;
+    pj_int16_t		       *mp3_sample_buf;
+    unsigned			mp3_sample_pos;
+    HBE_STREAM		        mp3_stream;
+    unsigned char	       *mp3_buf;
+};
+
+
+static pj_status_t file_put_frame(pjmedia_port *this_port, 
+				  const pjmedia_frame *frame);
+static pj_status_t file_get_frame(pjmedia_port *this_port, 
+				  pjmedia_frame *frame);
+static pj_status_t file_on_destroy(pjmedia_port *this_port);
+
+
+#if defined(PJ_WIN32) || defined(_WIN32) || defined(WIN32)
+
+#include <windows.h>
+#define DLL_NAME    PJ_T("LAME_ENC.DLL")
+
+/*
+ * Load BladeEncoder DLL.
+ */
+static pj_status_t init_blade_dll(void)
+{
+    if (BladeDLL.refCount == 0) {
+	#define GET_PROC(type, name)  \
+	    BladeDLL.name = (type)GetProcAddress(BladeDLL.hModule, PJ_T(#name)); \
+	    if (BladeDLL.name == NULL) { \
+		PJ_LOG(1,(THIS_FILE, "Unable to find %s in %s", #name, DLL_NAME)); \
+		return PJ_RETURN_OS_ERROR(GetLastError()); \
+	    }
+
+	BE_VERSION beVersion;
+	BladeDLL.hModule = (void*)LoadLibrary(DLL_NAME);
+	if (BladeDLL.hModule == NULL) {
+	    pj_status_t status = PJ_RETURN_OS_ERROR(GetLastError());
+	    char errmsg[PJ_ERR_MSG_SIZE];
+
+	    pj_strerror(status, errmsg, sizeof(errmsg));
+	    PJ_LOG(1,(THIS_FILE, "Unable to load %s: %s", DLL_NAME, errmsg));
+	    return status;
+	}
+
+	GET_PROC(BEINITSTREAM, beInitStream);
+	GET_PROC(BEENCODECHUNK, beEncodeChunk);
+	GET_PROC(BEDEINITSTREAM, beDeinitStream);
+	GET_PROC(BECLOSESTREAM, beCloseStream);
+	GET_PROC(BEVERSION, beVersion);
+	GET_PROC(BEWRITEVBRHEADER, beWriteVBRHeader);
+	GET_PROC(BEWRITEINFOTAG, beWriteInfoTag);
+
+	#undef GET_PROC
+
+	BladeDLL.beVersion(&beVersion);
+	PJ_LOG(4,(THIS_FILE, "%s encoder v%d.%d loaded (%s)", DLL_NAME,
+		  beVersion.byMajorVersion, beVersion.byMinorVersion,
+		  beVersion.zHomepage));
+    }
+    ++BladeDLL.refCount;
+    return PJ_SUCCESS;
+}
+
+/*
+ * Decrement the reference counter of the DLL.
+ */
+static void deinit_blade_dll()
+{
+    --BladeDLL.refCount;
+    if (BladeDLL.refCount == 0 && BladeDLL.hModule) {
+	FreeLibrary(BladeDLL.hModule);
+	BladeDLL.hModule = NULL;
+	PJ_LOG(4,(THIS_FILE, "%s unloaded", DLL_NAME));
+    }
+}
+
+#else
+
+static pj_status_t init_blade_dll(void)
+{
+    PJ_LOG(1,(THIS_FILE, "Error: MP3 writer port only works on Windows for now"));
+    return PJ_ENOTSUP;
+}
+
+static void deinit_blade_dll()
+{
+}
+#endif
+
+
+
+/*
+ * Initialize MP3 encoder.
+ */
+static pj_status_t init_mp3_encoder(struct mp3_file_port *fport,
+				    pj_pool_t *pool)
+{
+    BE_CONFIG LConfig;
+    unsigned  long InSamples;
+    unsigned  long OutBuffSize;
+    long MP3Err;
+
+    /*
+     * Initialize encoder configuration.
+     */
+    pj_bzero(&LConfig, sizeof(BE_CONFIG));
+    LConfig.dwConfig = BE_CONFIG_LAME;
+    LConfig.format.LHV1.dwStructVersion = 1;
+    LConfig.format.LHV1.dwStructSize = sizeof(BE_CONFIG);
+    LConfig.format.LHV1.dwSampleRate = fport->base.info.clock_rate;
+    LConfig.format.LHV1.dwReSampleRate = 0;
+
+    if (fport->base.info.channel_count==1)
+	LConfig.format.LHV1.nMode = BE_MP3_MODE_MONO;
+    else if (fport->base.info.channel_count==2)
+	LConfig.format.LHV1.nMode = BE_MP3_MODE_STEREO;
+    else
+	return PJMEDIA_ENCCHANNEL;
+
+    LConfig.format.LHV1.dwBitrate = fport->mp3_option.bit_rate / 1000;
+    LConfig.format.LHV1.nPreset = LQP_NOPRESET;
+    LConfig.format.LHV1.bCopyright = 0;
+    LConfig.format.LHV1.bCRC = 1;
+    LConfig.format.LHV1.bOriginal = 1;
+    LConfig.format.LHV1.bPrivate = 0;
+
+    if (!fport->mp3_option.vbr) {
+	LConfig.format.LHV1.nVbrMethod = VBR_METHOD_NONE;
+	LConfig.format.LHV1.bWriteVBRHeader = 0;
+	LConfig.format.LHV1.bEnableVBR = 0;
+    } else {
+	LConfig.format.LHV1.nVbrMethod = VBR_METHOD_DEFAULT;
+	LConfig.format.LHV1.bWriteVBRHeader = 1;
+	LConfig.format.LHV1.dwVbrAbr_bps = fport->mp3_option.bit_rate;
+	LConfig.format.LHV1.nVBRQuality =  (pj_uint16_t)
+					   fport->mp3_option.quality;
+	LConfig.format.LHV1.bEnableVBR = 1;
+    }
+
+    LConfig.format.LHV1.nQuality = (pj_uint16_t) 
+				   (((0-fport->mp3_option.quality-1)<<8) | 
+				    fport->mp3_option.quality);
+
+    /*
+     * Init MP3 stream.
+     */
+    InSamples = 0;
+    MP3Err = BladeDLL.beInitStream(&LConfig, &InSamples, &OutBuffSize,
+				   &fport->mp3_stream);
+    if (MP3Err != BE_ERR_SUCCESSFUL) 
+	return PJMEDIA_ERROR;
+
+    /*
+     * Allocate sample buffer.
+     */
+    fport->mp3_samples_per_frame = (unsigned)InSamples;
+    fport->mp3_sample_buf = pj_pool_alloc(pool, fport->mp3_samples_per_frame * 2);
+    if (!fport->mp3_sample_buf)
+	return PJ_ENOMEM;
+
+    /*
+     * Allocate encoded MP3 buffer.
+     */
+    fport->mp3_buf = pj_pool_alloc(pool, (pj_size_t)OutBuffSize);
+    if (fport->mp3_buf == NULL)
+	return PJ_ENOMEM;
+
+    
+    return PJ_SUCCESS;
+}
+
+
+/*
+ * Create MP3 file writer port.
+ */
+PJ_DEF(pj_status_t) 
+pjmedia_mp3_writer_port_create( pj_pool_t *pool,
+				const char *filename,
+				unsigned sampling_rate,
+				unsigned channel_count,
+				unsigned samples_per_frame,
+				unsigned bits_per_sample,
+				const pjmedia_mp3_encoder_option *param_option,
+				pjmedia_port **p_port )
+{
+    struct mp3_file_port *fport;
+    pj_status_t status;
+
+    status = init_blade_dll();
+    if (status != PJ_SUCCESS)
+	return status;
+
+    /* Check arguments. */
+    PJ_ASSERT_RETURN(pool && filename && p_port, PJ_EINVAL);
+
+    /* Only supports 16bits per sample for now. */
+    PJ_ASSERT_RETURN(bits_per_sample == 16, PJ_EINVAL);
+
+    /* Create file port instance. */
+    fport = pj_pool_zalloc(pool, sizeof(struct mp3_file_port));
+    PJ_ASSERT_RETURN(fport != NULL, PJ_ENOMEM);
+
+    /* Initialize port info. */
+    pj_strdup2_with_null(pool, &fport->mp3_filename, filename);
+    pjmedia_port_info_init(&fport->base.info, &fport->mp3_filename, SIGNATURE,
+			   sampling_rate, channel_count, bits_per_sample,
+			   samples_per_frame);
+
+    fport->base.get_frame = &file_get_frame;
+    fport->base.put_frame = &file_put_frame;
+    fport->base.on_destroy = &file_on_destroy;
+
+
+    /* Open file in write and read mode.
+     * We need the read mode because we'll modify the WAVE header once
+     * the recording has completed.
+     */
+    status = pj_file_open(pool, filename, PJ_O_WRONLY, &fport->fd);
+    if (status != PJ_SUCCESS) {
+	deinit_blade_dll();
+	return status;
+    }
+
+    /* Copy and initialize option with default settings */
+    if (param_option) {
+	pj_memcpy(&fport->mp3_option, param_option, 
+		   sizeof(pjmedia_mp3_encoder_option));
+    } else {
+	pj_bzero(&fport->mp3_option, sizeof(pjmedia_mp3_encoder_option));
+	fport->mp3_option.vbr = PJ_TRUE;
+    }
+
+    /* Calculate bitrate if it's not specified, only if it's not VBR. */
+    if (fport->mp3_option.bit_rate == 0 && !fport->mp3_option.vbr) 
+	fport->mp3_option.bit_rate = sampling_rate * channel_count;
+
+    /* Set default quality if it's not specified */
+    if (fport->mp3_option.quality == 0) 
+	fport->mp3_option.quality = 2;
+
+    /* Init mp3 encoder */
+    status = init_mp3_encoder(fport, pool);
+    if (status != PJ_SUCCESS) {
+	pj_file_close(fport->fd);
+	deinit_blade_dll();
+	return status;
+    }
+
+    /* Done. */
+    *p_port = &fport->base;
+
+    PJ_LOG(4,(THIS_FILE, 
+	      "MP3 file writer '%.*s' created: samp.rate=%dKHz, "
+	      "bitrate=%dkbps%s, quality=%d",
+	      (int)fport->base.info.name.slen,
+	      fport->base.info.name.ptr,
+	      fport->base.info.clock_rate/1000,
+	      fport->mp3_option.bit_rate/1000,
+	      (fport->mp3_option.vbr ? " (VBR)" : ""),
+	      fport->mp3_option.quality));
+
+    return PJ_SUCCESS;
+}
+
+
+
+/*
+ * Register callback.
+ */
+PJ_DEF(pj_status_t) 
+pjmedia_mp3_writer_port_set_cb( pjmedia_port *port,
+				pj_size_t pos,
+				void *user_data,
+			        pj_status_t (*cb)(pjmedia_port *port,
+						  void *usr_data))
+{
+    struct mp3_file_port *fport;
+
+    /* Sanity check */
+    PJ_ASSERT_RETURN(port && cb, PJ_EINVAL);
+
+    /* Check that this is really a writer port */
+    PJ_ASSERT_RETURN(port->info.signature == SIGNATURE, PJ_EINVALIDOP);
+
+    fport = (struct mp3_file_port*) port;
+
+    fport->cb_size = pos;
+    fport->base.port_data.pdata = user_data;
+    fport->cb = cb;
+
+    return PJ_SUCCESS;
+
+}
+
+
+/*
+ * Put a frame into the buffer. When the buffer is full, flush the buffer
+ * to the file.
+ */
+static pj_status_t file_put_frame(pjmedia_port *this_port, 
+				  const pjmedia_frame *frame)
+{
+    struct mp3_file_port *fport = (struct mp3_file_port *)this_port;
+    unsigned long MP3Err;
+    pj_ssize_t	bytes;
+    pj_status_t status;
+    unsigned long WriteSize;
+
+    /* Record silence if input is no-frame */
+    if (frame->type == PJMEDIA_FRAME_TYPE_NONE || frame->size == 0) {
+	unsigned samples_left = fport->base.info.samples_per_frame;
+	unsigned samples_copied = 0;
+
+	/* Only want to record at most 1 second of silence */
+	if (fport->silence_duration >= fport->base.info.clock_rate)
+	    return PJ_SUCCESS;
+
+	while (samples_left) {
+	    unsigned samples_needed = fport->mp3_samples_per_frame -
+				      fport->mp3_sample_pos;
+	    if (samples_needed > samples_left)
+		samples_needed = samples_left;
+
+	    pjmedia_zero_samples(fport->mp3_sample_buf + fport->mp3_sample_pos,
+				 samples_needed);
+	    fport->mp3_sample_pos += samples_needed;
+	    samples_left -= samples_needed;
+	    samples_copied += samples_needed;
+
+	    /* Encode if we have full frame */
+	    if (fport->mp3_sample_pos == fport->mp3_samples_per_frame) {
+		
+		/* Clear position */
+		fport->mp3_sample_pos = 0;
+
+		/* Encode ! */
+		MP3Err = BladeDLL.beEncodeChunk(fport->mp3_stream,
+						fport->mp3_samples_per_frame,
+						fport->mp3_sample_buf, 
+						fport->mp3_buf, 
+						&WriteSize);
+		if (MP3Err != BE_ERR_SUCCESSFUL)
+		    return PJMEDIA_ERROR;
+
+		/* Write the chunk */
+		bytes = WriteSize;
+		status = pj_file_write(fport->fd, fport->mp3_buf, &bytes);
+		if (status != PJ_SUCCESS)
+		    return status;
+
+		/* Increment total written. */
+		fport->total += bytes;
+	    }
+	}
+
+	fport->silence_duration += fport->base.info.samples_per_frame;
+
+    }
+    /* If encoder is expecting different sample size, then we need to
+     * buffer the samples.
+     */
+    else if (fport->mp3_samples_per_frame != 
+	     fport->base.info.samples_per_frame) 
+    {
+	unsigned samples_left = frame->size / 2;
+	unsigned samples_copied = 0;
+	const pj_int16_t *src_samples = frame->buf;
+
+	fport->silence_duration = 0;
+
+	while (samples_left) {
+	    unsigned samples_needed = fport->mp3_samples_per_frame -
+				      fport->mp3_sample_pos;
+	    if (samples_needed > samples_left)
+		samples_needed = samples_left;
+
+	    pjmedia_copy_samples(fport->mp3_sample_buf + fport->mp3_sample_pos,
+				 src_samples + samples_copied,
+				 samples_needed);
+	    fport->mp3_sample_pos += samples_needed;
+	    samples_left -= samples_needed;
+	    samples_copied += samples_needed;
+
+	    /* Encode if we have full frame */
+	    if (fport->mp3_sample_pos == fport->mp3_samples_per_frame) {
+		
+		/* Clear position */
+		fport->mp3_sample_pos = 0;
+
+		/* Encode ! */
+		MP3Err = BladeDLL.beEncodeChunk(fport->mp3_stream,
+						fport->mp3_samples_per_frame,
+						fport->mp3_sample_buf, 
+						fport->mp3_buf, 
+						&WriteSize);
+		if (MP3Err != BE_ERR_SUCCESSFUL)
+		    return PJMEDIA_ERROR;
+
+		/* Write the chunk */
+		bytes = WriteSize;
+		status = pj_file_write(fport->fd, fport->mp3_buf, &bytes);
+		if (status != PJ_SUCCESS)
+		    return status;
+
+		/* Increment total written. */
+		fport->total += bytes;
+	    }
+	}
+
+    } else {
+
+	fport->silence_duration = 0;
+
+	/* Encode ! */
+	MP3Err = BladeDLL.beEncodeChunk(fport->mp3_stream,
+					fport->mp3_samples_per_frame,
+					frame->buf, 
+					fport->mp3_buf, 
+					&WriteSize);
+	if (MP3Err != BE_ERR_SUCCESSFUL)
+	    return PJMEDIA_ERROR;
+
+	/* Write the chunk */
+	bytes = WriteSize;
+	status = pj_file_write(fport->fd, fport->mp3_buf, &bytes);
+	if (status != PJ_SUCCESS)
+	    return status;
+
+	/* Increment total written. */
+	fport->total += bytes;
+    }
+
+    /* Increment total written, and check if we need to call callback */
+    
+    if (fport->cb && fport->total >= fport->cb_size) {
+	pj_status_t (*cb)(pjmedia_port*, void*);
+	pj_status_t status;
+
+	cb = fport->cb;
+	fport->cb = NULL;
+
+	status = (*cb)(this_port, this_port->port_data.pdata);
+	return status;
+    }
+
+    return PJ_SUCCESS;
+}
+
+/*
+ * Get frame, basicy is a no-op operation.
+ */
+static pj_status_t file_get_frame(pjmedia_port *this_port, 
+				  pjmedia_frame *frame)
+{
+    PJ_UNUSED_ARG(this_port);
+    PJ_UNUSED_ARG(frame);
+    return PJ_EINVALIDOP;
+}
+
+
+/*
+ * Close the port, modify file header with updated file length.
+ */
+static pj_status_t file_on_destroy(pjmedia_port *this_port)
+{
+    struct mp3_file_port *fport = (struct mp3_file_port*)this_port;
+    pj_status_t status;
+    unsigned long WriteSize;
+    unsigned long MP3Err;
+
+
+    /* Close encoder */
+    MP3Err = BladeDLL.beDeinitStream(fport->mp3_stream, fport->mp3_buf, 
+				     &WriteSize);
+    if (MP3Err == BE_ERR_SUCCESSFUL) {
+	pj_ssize_t bytes = WriteSize;
+	status = pj_file_write(fport->fd, fport->mp3_buf, &bytes);
+    }
+
+    /* Close file */
+    status = pj_file_close(fport->fd);
+
+    /* Write additional VBR header */
+    if (fport->mp3_option.vbr) {
+	MP3Err = BladeDLL.beWriteVBRHeader(fport->mp3_filename.ptr);
+    }
+
+
+    /* Decrement DLL reference counter */
+    deinit_blade_dll();
+
+    /* Done. */
+    return PJ_SUCCESS;
+}
+