--- /dev/null
+/*
+ * 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):
+ *
+ * Brian K. West <brian.west@mac.com>
+ *
+ *
+ * mod_lpc10.c -- LPC10 Codec Module
+ *
+ */
+
+#include "switch.h"
+#include "lpc10/lpc10.h"
+
+enum {
+ SamplesPerFrame = 180,
+ BitsPerFrame = 54,
+ BytesPerFrame = (BitsPerFrame+7)/8,
+ BitsPerSecond = 2400
+};
+
+#define SampleValueScale 32768.0
+#define MaxSampleValue 32767.0
+#define MinSampleValue -32767.0
+
+static const char modname[] = "mod_lpc10";
+
+struct lpc10_context {
+ struct lpc10_encoder_state encoder_object;
+ struct lpc10_decoder_state decoder_object;
+};
+
+static switch_status_t switch_lpc10_init(switch_codec_t *codec, switch_codec_flag_t flags,
+ const switch_codec_settings_t *codec_settings)
+{
+ uint32_t encoding, decoding;
+ struct lpc10_context *context = NULL;
+
+ encoding = (flags & SWITCH_CODEC_FLAG_ENCODE);
+ decoding = (flags & SWITCH_CODEC_FLAG_DECODE);
+
+ if (!(encoding || decoding) || (!(context = switch_core_alloc(codec->memory_pool, sizeof(struct lpc10_context))))) {
+ return SWITCH_STATUS_FALSE;
+ } else {
+
+ if (encoding) {
+ init_lpc10_encoder_state(&context->encoder_object);
+ }
+
+ if (decoding) {
+ init_lpc10_decoder_state(&context->decoder_object);
+ }
+
+ codec->private_info = context;
+
+ return SWITCH_STATUS_SUCCESS;
+ }
+}
+
+
+static switch_status_t switch_lpc10_destroy(switch_codec_t *codec)
+{
+ codec->private_info = NULL;
+ return SWITCH_STATUS_SUCCESS;
+}
+
+static switch_status_t switch_lpc10_encode(switch_codec_t *codec,
+ switch_codec_t *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 lpc10_context *context = codec->private_info;
+ int i;
+ INT32 bits[BitsPerFrame];
+ real speech[SamplesPerFrame];
+ short * sampleBuffer = (short *)encoded_data;
+ unsigned char * buffer = (unsigned char *)decoded_data;
+
+
+
+ if (!context) {
+ return SWITCH_STATUS_FALSE;
+ }
+
+ for (i = 0; i < SamplesPerFrame; i++)
+ speech[i] = (real)(sampleBuffer[i]/SampleValueScale);
+
+ lpc10_encode(speech, bits, &context->encoder_object);
+
+ memset(encoded_data, 0, BytesPerFrame);
+ for (i = 0; i < BitsPerFrame; i++) {
+ if (bits[i])
+ buffer[i>>3] |= 1 << (i&7);
+ }
+
+ *encoded_data_len = BytesPerFrame;
+
+ return SWITCH_STATUS_SUCCESS;
+}
+
+static switch_status_t switch_lpc10_decode(switch_codec_t *codec,
+ switch_codec_t *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 lpc10_context *context = codec->private_info;
+ int i;
+ INT32 bits[BitsPerFrame];
+ real speech[SamplesPerFrame];
+ short * sampleBuffer = (short *)decoded_data;
+ unsigned char * buffer = (unsigned char *)encoded_data;
+
+ if (!context) {
+ return SWITCH_STATUS_FALSE;
+ }
+
+ for (i = 0; i < BitsPerFrame; i++)
+ bits[i] = (buffer[i>>3]&(1<<(i&7))) != 0;
+
+ lpc10_decode(bits, speech, &context->decoder_object);
+
+ for (i = 0; i < SamplesPerFrame; i++) {
+ real sample = (real)(speech[i]*SampleValueScale);
+ if (sample < MinSampleValue)
+ sample = MinSampleValue;
+ else if (sample > MaxSampleValue)
+ sample = MaxSampleValue;
+ sampleBuffer[i] = (short)sample;
+ }
+
+ *decoded_data_len = SamplesPerFrame*2;
+
+ return SWITCH_STATUS_SUCCESS;
+}
+
+/* Registration */
+
+static const switch_codec_implementation_t lpc10_implementation = {
+ /*.codec_type */ SWITCH_CODEC_TYPE_AUDIO,
+ /*.ianacode */ 7,
+ /*.iananame */ "LPC",
+ /*.samples_per_second */ 8000,
+ /*.bits_per_second */ 240,
+ /*.microseconds_per_frame */ 22500,
+ /*.samples_per_frame */ 180,
+ /*.bytes_per_frame */ 360,
+ /*.encoded_bytes_per_frame */ 7,
+ /*.number_of_channels */ 1,
+ /*.pref_frames_per_packet */ 1,
+ /*.max_frames_per_packet */ 1,
+ /*.init */ switch_lpc10_init,
+ /*.encode */ switch_lpc10_encode,
+ /*.decode */ switch_lpc10_decode,
+ /*.destroy */ switch_lpc10_destroy,
+};
+
+const switch_codec_interface_t lpc10_codec_interface = {
+ /*.interface_name */ "LPC-10 2.4kbps",
+ /*.implementations */ &lpc10_implementation,
+};
+
+static switch_loadable_module_interface_t lpc10_module_interface = {
+ /*.module_name */ modname,
+ /*.endpoint_interface */ NULL,
+ /*.timer_interface */ NULL,
+ /*.dialplan_interface */ NULL,
+ /*.codec_interface */ &lpc10_codec_interface,
+ /*.application_interface */ NULL
+};
+
+SWITCH_MOD_DECLARE(switch_status_t) switch_module_load(const switch_loadable_module_interface_t **module_interface,
+ char *filename)
+{
+ /* connect my internal structure to the blank pointer passed to me */
+ *module_interface = &lpc10_module_interface;
+
+ /* indicate that the module should continue to be loaded */
+ return SWITCH_STATUS_SUCCESS;
+}
projects / thirdparty / freeswitch.git / commitdiff
