/* * RFC3267/RFC4867 GSM-AMR Plugin codec for OpenH323/OPAL * * Copyright (C) 2004 MX Telecom Ltd. * * $Revision: 20629 $ * $Author: rjongbloed $ * $Date: 2008-07-28 07:57:33 +0000 (Mon, 28 Jul 2008) $ */ #define _CRT_NONSTDC_NO_DEPRECATE 1 #define _CRT_SECURE_NO_WARNINGS 1 #include #include #include #ifndef PLUGIN_CODEC_DLL_EXPORTS #include "plugin-config.h" #endif #include #include "src/interf_enc.h" #include "src/interf_dec.h" #include "src/interf_rom.h" #include "src/rom_dec.h" #ifndef FALSE #define FALSE 0 #endif #ifndef TRUE #define TRUE (!FALSE) #endif #if defined(_WIN32) || defined(_WIN32_WCE) #define STRCMPI _strcmpi #else #define STRCMPI strcasecmp #endif /*Disable some warnings on VC++*/ #ifdef _MSC_VER #pragma warning(disable : 4100) #endif /*************************************************************************** * * This plugin implements an interface to the GSM-AMR codec for OpenH323 (H.245 Annex I) * This should not be confused with GSM-AMR-NB (H.245 Annex R) * * The amr codec itself is not distributed with this plugin. See amrcodec.txt * in the src subdirectory of the plugin source. * * This code can currently only handle one frame per packet due to the RFC3267 * packetisation method which is ... difficult ... with the current OPAL plug in * architecture. So make sure "Rx Frames Per Packet" doesn;t change till it's fixed! * **************************************************************************/ /* generic parameters; see H.245 Annex I */ enum { H245_AMR_MAXAL_SDUFRAMES = 0 | PluginCodec_H245_Collapsing | PluginCodec_H245_TCS | PluginCodec_H245_OLC, H245_AMR_BITRATE = 1 | PluginCodec_H245_NonCollapsing | PluginCodec_H245_ReqMode, H245_AMR_GSMAMRCOMFORTNOISE = 2 | PluginCodec_H245_Collapsing | PluginCodec_H245_ReqMode | PluginCodec_H245_OLC, H245_AMR_GSMEFRCOMFORTNOISE = 3 | PluginCodec_H245_Collapsing | PluginCodec_H245_ReqMode | PluginCodec_H245_TCS | PluginCodec_H245_OLC, H245_AMR_IS_641COMFORTNOISE = 4 | PluginCodec_H245_Collapsing | PluginCodec_H245_ReqMode | PluginCodec_H245_TCS | PluginCodec_H245_OLC, H245_AMR_PDCEFRCOMFORTNOISE = 5 | PluginCodec_H245_Collapsing | PluginCodec_H245_ReqMode | PluginCodec_H245_TCS | PluginCodec_H245_OLC }; /* values of the bit rate parameter */ enum { AMR_BITRATE_475 = 0, AMR_BITRATE_515, AMR_BITRATE_590, AMR_BITRATE_670, AMR_BITRATE_740, AMR_BITRATE_795, AMR_BITRATE_1020, AMR_BITRATE_1220, AMR_BITRATE_CN, AMR_BITRATE_EFR, AMR_BITRATE_IS641, AMR_BITRATE_PDCEFR, AMR_BITRATE_DTX = 15 }; // this is what we hand back when we are asked to create an encoder typedef struct { void * encoder_state; // Encoder interface's opaque state unsigned mode; // current mode int vad; // silence suppression } AmrEncoderContext; ///////////////////////////////////////////////////////////////////////////// static void * amr_create_encoder(const struct PluginCodec_Definition * codec) { AmrEncoderContext * amr = malloc(sizeof(AmrEncoderContext)); if (amr == NULL ) return NULL; amr->encoder_state = Encoder_Interface_init(amr->vad); if (amr->encoder_state == NULL ) { free(amr); return NULL; } amr->mode = AMR_BITRATE_1220; // start off in mode 12.2kbps mode amr->vad = TRUE; return amr; } static void * amr_create_decoder(const struct PluginCodec_Definition * codec) { return Decoder_Interface_init(); } static void amr_destroy_encoder(const struct PluginCodec_Definition * codec, void * context) { AmrEncoderContext * amr = (AmrEncoderContext *)context; Encoder_Interface_exit(amr->encoder_state); free(amr); } static void amr_destroy_decoder(const struct PluginCodec_Definition * codec, void * context) { Decoder_Interface_exit(context); } static int amr_codec_encoder(const struct PluginCodec_Definition * codec, void * context, const void * fromPtr, unsigned * fromLen, void * toPtr, unsigned * toLen, unsigned int * flag) { AmrEncoderContext * amr = (AmrEncoderContext *)context; unsigned byteCount; unsigned char buffer[100]; // Need this as encoder is very rude and can output more bytes than to pointer might be pointing to if (*fromLen < L_FRAME*sizeof(short)) return FALSE; byteCount = Encoder_Interface_Encode(amr->encoder_state, (enum Mode)amr->mode, (const short *)fromPtr, buffer+1, 0); if (byteCount <= 1 || *toLen <= byteCount) { *toLen = 0; return byteCount == 1; // Is a DTX frame } buffer[0] = 0xf0; // CMR is always this for us memcpy(toPtr, buffer, *toLen); *toLen = byteCount+1; *fromLen = L_FRAME*sizeof(short); return TRUE; } static int amr_codec_decoder(const struct PluginCodec_Definition * codec, void * context, const void * fromPtr, unsigned * fromLen, void * toPtr, unsigned * toLen, unsigned int * flag) { unsigned char * packet; if (*toLen < L_FRAME*sizeof(short)) return FALSE; if (fromLen == NULL || *fromLen == 0) { unsigned char buffer[32]; buffer[0] = (AMR_BITRATE_DTX << 3)|4; Decoder_Interface_Decode(context, buffer, (short *)toPtr, 0); // Handle missing data return TRUE; } packet = (unsigned char *)fromPtr; Decoder_Interface_Decode(context, packet+1, (short *)toPtr, 0); // Skip over CMR *fromLen = block_size[packet[1] >> 3] + 1; // Actual bytes consumed *toLen = L_FRAME*sizeof(short); return TRUE; } static int amr_set_quality(const struct PluginCodec_Definition * codec, void * context, const char * name, void * parm, unsigned * parmLen) { int quality; if (parm == NULL || *parmLen != sizeof(quality)) return FALSE; quality = *(int *)parm; if (quality < 0) quality = 0; else if (quality > 31) quality = 31; /* 1-3 -> mode 7 4-7 -> mode 6 ... 28-31 -> mode 0 */ ((AmrEncoderContext *)context)->mode = 7 -(quality/4); return TRUE; } static int amr_get_quality(const struct PluginCodec_Definition * codec, void * context, const char * name, void * parm, unsigned * parmLen) { if (parm == NULL || *parmLen != sizeof(int)) return FALSE; *(int *)parm = (7 - ((AmrEncoderContext *)context)->mode)*4; return TRUE; } ///////////////////////////////////////////////////////////////////////////// static struct PluginCodec_Option const amrRxFramesPerPacket = { PluginCodec_IntegerOption, // PluginCodec_OptionTypes "Rx Frames Per Packet", // Generic (human readable) option name 0, // Read Only flag PluginCodec_MinMerge, // Merge mode "1", // Initial value NULL, // SIP/SDP FMTP name NULL, // SIP/SDP FMTP default value (option not included in FMTP if have this value) H245_AMR_MAXAL_SDUFRAMES, // H.245 Generic Capability number and scope bits "1", // Minimum value "1" // Maximum value // Do not change!! See above. }; static const char InitialModeStr[] = "Initial Mode"; static struct PluginCodec_Option const amrInitialMode = { PluginCodec_IntegerOption, // PluginCodec_OptionTypes InitialModeStr, // Generic (human readable) option name 0, // Read Only flag PluginCodec_NoMerge, // Merge mode "7", // Initial value NULL, // SIP/SDP FMTP name NULL, // SIP/SDP FMTP default value (option not included in FMTP if have this value) H245_AMR_BITRATE, // H.245 Generic Capability number and scope bits "0", // Minimum value "7" // Maximum value }; static const char VADStr[] = "VAD"; static struct PluginCodec_Option const amrVAD = { PluginCodec_BoolOption, // PluginCodec_OptionTypes VADStr, // Generic (human readable) option name 0, // Read Only flag PluginCodec_AndMerge, // Merge mode "True", // Initial value NULL, // SIP/SDP FMTP name NULL, // SIP/SDP FMTP default value (option not included in FMTP if have this value) H245_AMR_GSMAMRCOMFORTNOISE // H.245 Generic Capability number and scope bitsSE, }; static struct PluginCodec_Option const amrMediaPacketization = { PluginCodec_StringOption, // PluginCodec_OptionTypes "Media Packetization", // Generic (human readable) option name 0, // Read Only flag PluginCodec_EqualMerge, // Merge mode "RFC3267" // Initial value }; static struct PluginCodec_Option const * const amrOptionTable[] = { &amrRxFramesPerPacket, &amrInitialMode, &amrVAD, &amrMediaPacketization, NULL }; static int get_codec_options(const struct PluginCodec_Definition * defn, void * context, const char * name, void * parm, unsigned * parmLen) { if (parm == NULL || parmLen == NULL || *parmLen != sizeof(struct PluginCodec_Option **)) return FALSE; *(struct PluginCodec_Option const * const * *)parm = amrOptionTable; return TRUE; } static int set_codec_options(const struct PluginCodec_Definition * defn, void * context, const char * name, void * parm, unsigned * parmLen) { const char * const * option; AmrEncoderContext * amr; if (context == NULL || parm == NULL || parmLen == NULL || *parmLen != sizeof(const char **)) return FALSE; amr = (AmrEncoderContext *)context; for (option = (const char * const *)parm; *option != NULL; option += 2) { if (STRCMPI(option[0], InitialModeStr) == 0) { amr->mode = strtoul(option[1], NULL, 10); if (amr->mode > AMR_BITRATE_1220) amr->mode = AMR_BITRATE_1220; } else if (STRCMPI(option[0], VADStr) == 0) amr->vad = atoi(option[1]) != 0; } return TRUE; } ///////////////////////////////////////////////////////////////////////////// static struct PluginCodec_information licenseInfo = { // Tue 13 Jul 2004 00:11:32 UTC = 1089677492, "Richard van der Hoff, MX Telecom Ltd.", // source code author "$Ver$", // source code version "richardv@mxtelecom.com", // source code email "http://www.mxtelecom.com", // source code URL "Copyright (C) 2004 MX Telecom Ltd.", // source code copyright "None", // source code license // FIXME PluginCodec_License_None, // source code license "GSM-AMR (Adaptive Multirate Codec)", // codec description "3rd Generation Partnership Project", // codec author NULL, // codec version NULL, // codec email "http://www.3gpp.org", // codec URL "", // codec copyright information "", // codec license PluginCodec_License_RoyaltiesRequired // codec license code }; static struct PluginCodec_ControlDefn amrEncoderControlDefn[] = { { "get_codec_options", get_codec_options }, { "set_codec_options", set_codec_options }, { "set_quality", amr_set_quality }, { "get_quality", amr_get_quality }, { NULL } }; static const struct PluginCodec_H323GenericCodecData amrcap = { OpalPluginCodec_Identifer_AMR, // capability identifier (Ref: Table I.1 in H.245) 122 // Must always be this regardless of "Max Bit Rate" option }; static struct PluginCodec_Definition amrCodecDefn[] = { { // encoder PLUGIN_CODEC_VERSION_OPTIONS, // codec API version &licenseInfo, // license information PluginCodec_MediaTypeAudio | // audio codec PluginCodec_InputTypeRaw | // raw input data PluginCodec_OutputTypeRaw | // raw output data PluginCodec_RTPTypeDynamic, // dynamic RTP type "GSM-AMR", // text decription "L16", // source format "GSM-AMR", // destination format NULL, // user data 8000, // samples per second 12200, // raw bits per second 20000, // microseconds per frame L_FRAME, // samples per frame 33, // bytes per frame 1, // recommended number of frames per packet 1, // maximum number of frames per packet 0, // IANA RTP payload code "AMR", // RTP payload name amr_create_encoder, // create codec function amr_destroy_encoder, // destroy codec amr_codec_encoder, // encode/decode amrEncoderControlDefn, // codec controls PluginCodec_H323Codec_generic, // h323CapabilityType &amrcap // h323CapabilityData }, { // decoder PLUGIN_CODEC_VERSION_OPTIONS, // codec API version &licenseInfo, // license information PluginCodec_MediaTypeAudio | // audio codec PluginCodec_InputTypeRaw | // raw input data PluginCodec_OutputTypeRaw | // raw output data PluginCodec_RTPTypeDynamic | // dynamic RTP type PluginCodec_DecodeSilence, // Can accept missing (empty) frames and generate silence "GSM-AMR", // text decription "GSM-AMR", // source format "L16", // destination format NULL, // user data 8000, // samples per second 12200, // raw bits per second 30000, // microseconds per frame L_FRAME, // samples per frame 33, // bytes per frame 1, // recommended number of frames per packet 1, // maximum number of frames per packet 0, // IANA RTP payload code "AMR", // RTP payload name amr_create_decoder, // create codec function amr_destroy_decoder, // destroy codec amr_codec_decoder, // encode/decode NULL, // codec controls PluginCodec_H323Codec_generic, // h323CapabilityType &amrcap // h323CapabilityData } }; PLUGIN_CODEC_IMPLEMENT_ALL(AMR, amrCodecDefn, PLUGIN_CODEC_VERSION_OPTIONS) /////////////////////////////////////////////////////////////////////////////