freeswitch/src/mod/codecs/mod_ilbc/mod_ilbc.c

/* 
 * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 * Copyright (C) 2005/2006, Anthony Minessale II <anthmct@yahoo.com>
 *
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 *
 * The Initial Developer of the Original Code is
 * Anthony Minessale II <anthmct@yahoo.com>
 * Portions created by the Initial Developer are Copyright (C)
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 * 
 * Anthony Minessale II <anthmct@yahoo.com>
 * Michael Jerris <mike@jerris.com>
 *
 * mod_ilbc.c -- ilbc Codec Module
 *
 */  
#include "switch.h"
#include "iLBC_encode.h"
#include "iLBC_decode.h"
#include "iLBC_define.h"

static const char modname[] = "mod_ilbc";

struct ilbc_context {
	iLBC_Enc_Inst_t encoder;
	iLBC_Dec_Inst_t decoder;
	uint8_t ms;
	uint16_t bytes;
	uint16_t dbytes;
};

static switch_status switch_ilbc_init(switch_codec *codec, switch_codec_flag flags,
									  const struct switch_codec_settings *codec_settings) 
{
	struct ilbc_context *context;
	int encoding, decoding;
	uint8_t ms = codec->implementation->microseconds_per_frame / 1000;


	if (ms != 20 && ms != 30) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "invalid speed! (I should never happen)\n");
		return SWITCH_STATUS_FALSE;
	}

	encoding = (flags & SWITCH_CODEC_FLAG_ENCODE);
	decoding = (flags & SWITCH_CODEC_FLAG_DECODE);

	if (!(encoding || decoding)) {
		return SWITCH_STATUS_FALSE;
	} else {
		context = switch_core_alloc(codec->memory_pool, sizeof(*context));
		context->ms = ms;
		if (context->ms == 20) {
			context->bytes = NO_OF_BYTES_20MS;
			context->dbytes = 320;
		} else {
			context->bytes = NO_OF_BYTES_30MS;
			context->dbytes = 480;
		}

		if (encoding) {
			initEncode(&context->encoder, context->ms);
		}
		if (decoding) {
			initDecode(&context->decoder, context->ms, 1);
		}
	}

	codec->private_info = context;
	return SWITCH_STATUS_SUCCESS;
}


static switch_status switch_ilbc_destroy(switch_codec *codec) 
{
	codec->private_info = NULL;
	return SWITCH_STATUS_SUCCESS;
}


static switch_status switch_ilbc_encode(switch_codec *codec,
										 switch_codec *other_codec,
										 void *decoded_data,
										 uint32_t decoded_data_len,
										 uint32_t decoded_rate,
										 void *encoded_data,
										 uint32_t *encoded_data_len, 
										 uint32_t *encoded_rate,
										 unsigned int *flag)
{
	struct ilbc_context *context = codec->private_info;

	if (!context) {
		return SWITCH_STATUS_FALSE;
	}
	if (decoded_data_len % context->dbytes == 0) {
		unsigned int new_len = 0;
		unsigned char *edp = encoded_data;
		short *ddp = decoded_data;
		int x;
		uint16_t y;
		int loops = (int) decoded_data_len / context->dbytes;
		float buf[240];

		for (x = 0; x < loops && new_len < *encoded_data_len; x++) {
			for(y = 0; y < context->dbytes / sizeof(short) ; y++) {
				buf[y] = ddp[y];
			}
			iLBC_encode(edp, buf, &context->encoder);
			edp += context->bytes;
			ddp += context->dbytes;
			new_len += context->bytes;
		}
		if (new_len <= *encoded_data_len) {
			*encoded_data_len = new_len;
		} else {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "buffer overflow!!! %u >= %u\n", new_len, *encoded_data_len);
			return SWITCH_STATUS_FALSE;
		}
	}
	return SWITCH_STATUS_SUCCESS;
}

static switch_status switch_ilbc_decode(switch_codec *codec,
										switch_codec *other_codec,
										void *encoded_data,
										uint32_t encoded_data_len,
										uint32_t encoded_rate,
										void *decoded_data,
										uint32_t *decoded_data_len, 
										uint32_t *decoded_rate, 
										unsigned int *flag)
{
	struct ilbc_context *context = codec->private_info;

	if (!context) {
		return SWITCH_STATUS_FALSE;
	}

	if (encoded_data_len % context->bytes == 0) {
		int loops = (int) encoded_data_len / context->bytes;
		unsigned char *edp = encoded_data;
		short *ddp = decoded_data;
		int x;
		uint16_t y;
		unsigned int new_len = 0;
		float buf[240];

		for (x = 0; x < loops && new_len < *decoded_data_len; x++) {
			iLBC_decode(buf, edp, &context->decoder, 1);
			for(y = 0; y < context->dbytes / sizeof(short) ; y++) {
				ddp[y] = (short)buf[y];
			}
			ddp += context->dbytes / sizeof(short);
			edp += context->bytes;
			new_len += context->dbytes;
		}
		if (new_len <= *decoded_data_len) {
			*decoded_data_len = new_len;
		} else {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "buffer overflow!!!\n");
			return SWITCH_STATUS_FALSE;
		}
	} else {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "yo this frame is an odd size [%d]\n", encoded_data_len);
	}
	return SWITCH_STATUS_SUCCESS;
}


/* Registration */ 

static const switch_codec_implementation ilbc_8k_30ms_implementation = { 
		/*.samples_per_second */ 8000, 
		/*.bits_per_second */ NO_OF_BYTES_30MS*8*8000/BLOCKL_30MS,
		/*.microseconds_per_frame */ 30000,
		/*.samples_per_frame */ 240,
		/*.bytes_per_frame */ 480,
		/*.encoded_bytes_per_frame */ NO_OF_BYTES_30MS,
		/*.number_of_channels */ 1,
		/*.pref_frames_per_packet */ 1,
		/*.max_frames_per_packet */ 1,
		/*.init */ switch_ilbc_init,
		/*.encode */ switch_ilbc_encode,
		/*.decode */ switch_ilbc_decode,
		/*.destroy */ switch_ilbc_destroy
};

static const switch_codec_implementation ilbc_8k_20ms_implementation = { 
		/*.samples_per_second */ 8000, 
		/*.bits_per_second */ NO_OF_BYTES_20MS*8*8000/BLOCKL_20MS, 
		/*.microseconds_per_frame */ 20000,
		/*.samples_per_frame */ 160,
		/*.bytes_per_frame */ 320,
		/*.encoded_bytes_per_frame */ NO_OF_BYTES_20MS, 
		/*.number_of_channels */ 1,
		/*.pref_frames_per_packet */ 1,
		/*.max_frames_per_packet */ 1,
		/*.init */ switch_ilbc_init,
		/*.encode */ switch_ilbc_encode,
		/*.decode */ switch_ilbc_decode,
		/*.destroy */ switch_ilbc_destroy,
		/*.next */ &ilbc_8k_30ms_implementation
};


static const switch_codec_implementation ilbc_8k_20ms_nonext_implementation = { 
		/*.samples_per_second */ 8000, 
		/*.bits_per_second */ NO_OF_BYTES_20MS*8*8000/BLOCKL_20MS, 
		/*.microseconds_per_frame */ 20000,
		/*.samples_per_frame */ 160,
		/*.bytes_per_frame */ 320,
		/*.encoded_bytes_per_frame */ NO_OF_BYTES_20MS, 
		/*.number_of_channels */ 1,
		/*.pref_frames_per_packet */ 1,
		/*.max_frames_per_packet */ 1,
		/*.init */ switch_ilbc_init,
		/*.encode */ switch_ilbc_encode,
		/*.decode */ switch_ilbc_decode,
		/*.destroy */ switch_ilbc_destroy
};


static const switch_codec_interface ilbc_20ms_codec_interface = { 
		/*.interface_name */ "ilbc", 
		/*.codec_type */ SWITCH_CODEC_TYPE_AUDIO, 
		/*.ianacode */ 97, 
		/*.iananame */ "iLBC20ms",
		/*.implementations */ &ilbc_8k_20ms_nonext_implementation
};

static const switch_codec_interface ilbc_102_codec_interface = { 
		/*.interface_name */ "ilbc", 
		/*.codec_type */ SWITCH_CODEC_TYPE_AUDIO, 
		/*.ianacode */ 102, 
		/*.iananame */ "iLBC102", 
		/*.implementations */ &ilbc_8k_20ms_implementation, 
		/*.next*/ &ilbc_20ms_codec_interface
};

static const switch_codec_interface ilbc_codec_interface = { 
		/*.interface_name */ "ilbc", 
		/*.codec_type */ SWITCH_CODEC_TYPE_AUDIO, 
		/*.ianacode */ 97, 
		/*.iananame */ "iLBC", 
		/*.implementations */ &ilbc_8k_20ms_implementation, 
		/*.next*/ &ilbc_102_codec_interface
};


static switch_loadable_module_interface ilbc_module_interface = { 
		/*.module_name */ modname, 
		/*.endpoint_interface */ NULL, 
		/*.timer_interface */ NULL, 
		/*.dialplan_interface */ NULL, 
		/*.codec_interface */ &ilbc_codec_interface, 
		/*.application_interface */ NULL 
};



SWITCH_MOD_DECLARE(switch_status) switch_module_load(const switch_loadable_module_interface **interface,
														char *filename)
{
	
		/* connect my internal structure to the blank pointer passed to me */ 
		*interface = &ilbc_module_interface;
	

		/* indicate that the module should continue to be loaded */ 
		return SWITCH_STATUS_SUCCESS;

}