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-rw-r--r--trunk/codecs/codec_a_mu.c159
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diff --git a/trunk/codecs/codec_a_mu.c b/trunk/codecs/codec_a_mu.c
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+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 1999 - 2005, Digium, Inc.
+ *
+ * Mark Spencer <markster@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! \file
+ *
+ * \brief codec_a_mu.c - translate between alaw and ulaw directly
+ *
+ * \ingroup codecs
+ */
+
+#include "asterisk.h"
+
+ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
+
+#include "asterisk/module.h"
+#include "asterisk/translate.h"
+#include "asterisk/alaw.h"
+#include "asterisk/ulaw.h"
+#include "asterisk/utils.h"
+
+#define BUFFER_SAMPLES 8000 /* size for the translation buffers */
+
+static unsigned char mu2a[256];
+static unsigned char a2mu[256];
+
+/* Sample frame data (Mu data is okay) */
+
+#include "ulaw_slin_ex.h"
+
+/*! \brief convert frame data and store into the buffer */
+static int alawtoulaw_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
+{
+ int x = f->samples;
+ unsigned char *src = f->data;
+ unsigned char *dst = (unsigned char *)pvt->outbuf + pvt->samples;
+
+ pvt->samples += x;
+ pvt->datalen += x;
+
+ while (x--)
+ *dst++ = a2mu[*src++];
+
+ return 0;
+}
+
+/*! \brief convert frame data and store into the buffer */
+static int ulawtoalaw_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
+{
+ int x = f->samples;
+ unsigned char *src = f->data;
+ unsigned char *dst = (unsigned char *)pvt->outbuf + pvt->samples;
+
+ pvt->samples += x;
+ pvt->datalen += x;
+
+ while (x--)
+ *dst++ = mu2a[*src++];
+
+ return 0;
+}
+
+/*
+ * alawToLin_Sample. Just random data, somehow...
+ */
+static struct ast_frame *alawtoulaw_sample(void)
+{
+ static struct ast_frame f;
+ f.frametype = AST_FRAME_VOICE;
+ f.subclass = AST_FORMAT_ALAW;
+ f.datalen = sizeof(ulaw_slin_ex);
+ f.samples = sizeof(ulaw_slin_ex);
+ f.mallocd = 0;
+ f.offset = 0;
+ f.src = __PRETTY_FUNCTION__;
+ f.data = ulaw_slin_ex; /* XXX what ? */
+ return &f;
+}
+
+static struct ast_frame *ulawtoalaw_sample(void)
+{
+ static struct ast_frame f;
+ f.frametype = AST_FRAME_VOICE;
+ f.subclass = AST_FORMAT_ULAW;
+ f.datalen = sizeof(ulaw_slin_ex);
+ f.samples = sizeof(ulaw_slin_ex);
+ f.mallocd = 0;
+ f.offset = 0;
+ f.src = __PRETTY_FUNCTION__;
+ f.data = ulaw_slin_ex;
+ return &f;
+}
+
+static struct ast_translator alawtoulaw = {
+ .name = "alawtoulaw",
+ .srcfmt = AST_FORMAT_ALAW,
+ .dstfmt = AST_FORMAT_ULAW,
+ .framein = alawtoulaw_framein,
+ .sample = alawtoulaw_sample,
+ .buffer_samples = BUFFER_SAMPLES,
+ .buf_size = BUFFER_SAMPLES,
+};
+
+static struct ast_translator ulawtoalaw = {
+ .name = "ulawtoalaw",
+ .srcfmt = AST_FORMAT_ULAW,
+ .dstfmt = AST_FORMAT_ALAW,
+ .framein = ulawtoalaw_framein,
+ .sample = ulawtoalaw_sample,
+ .buffer_samples = BUFFER_SAMPLES,
+ .buf_size = BUFFER_SAMPLES,
+};
+
+/*! \brief standard module glue */
+
+static int unload_module(void)
+{
+ int res;
+
+ res = ast_unregister_translator(&ulawtoalaw);
+ res |= ast_unregister_translator(&alawtoulaw);
+
+ return res;
+}
+
+static int load_module(void)
+{
+ int res;
+ int x;
+
+ for (x=0;x<256;x++) {
+ mu2a[x] = AST_LIN2A(AST_MULAW(x));
+ a2mu[x] = AST_LIN2MU(AST_ALAW(x));
+ }
+ res = ast_register_translator(&alawtoulaw);
+ if (!res)
+ res = ast_register_translator(&ulawtoalaw);
+ else
+ ast_unregister_translator(&alawtoulaw);
+ if (res)
+ return AST_MODULE_LOAD_FAILURE;
+ return AST_MODULE_LOAD_SUCCESS;
+}
+
+AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "A-law and Mulaw direct Coder/Decoder");