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authormarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>2001-12-09 00:41:43 +0000
committermarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>2001-12-09 00:41:43 +0000
commit73f433504205e9996ef28ea925881851caa392a3 (patch)
treee900c1cb311ee485c9707a595d48283480f82847 /codecs/codec_alaw.c
parent20550ee5133b6ddb2f233e78f8fa9bb9cb0b6de5 (diff)
Version 0.1.10 from FTP
git-svn-id: http://svn.digium.com/svn/asterisk/trunk@392 f38db490-d61c-443f-a65b-d21fe96a405b
Diffstat (limited to 'codecs/codec_alaw.c')
-rwxr-xr-xcodecs/codec_alaw.c378
1 files changed, 378 insertions, 0 deletions
diff --git a/codecs/codec_alaw.c b/codecs/codec_alaw.c
new file mode 100755
index 000000000..9089fccbe
--- /dev/null
+++ b/codecs/codec_alaw.c
@@ -0,0 +1,378 @@
+/* codec_alaw.c - translate between signed linear and alaw
+ *
+ * Asterisk -- A telephony toolkit for Linux.
+ *
+ * Copyright (c) 2001 Linux Support Services, Inc. All rights reserved.
+ *
+ * Mark Spencer <markster@linux-support.net
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License
+ */
+
+#include <asterisk/logger.h>
+#include <asterisk/module.h>
+#include <asterisk/translate.h>
+#include <asterisk/channel.h>
+#include <asterisk/alaw.h>
+#include <fcntl.h>
+#include <netinet/in.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define BUFFER_SIZE 8096 /* size for the translation buffers */
+
+static pthread_mutex_t localuser_lock = PTHREAD_MUTEX_INITIALIZER;
+static int localusecnt = 0;
+
+static char *tdesc = "A-law Coder/Decoder";
+
+/* Sample frame data (Mu data is okay) */
+
+#include "slin_ulaw_ex.h"
+#include "ulaw_slin_ex.h"
+
+/*
+ * Private workspace for translating signed linear signals to alaw.
+ */
+
+struct alaw_encoder_pvt
+{
+ struct ast_frame f;
+ char offset[AST_FRIENDLY_OFFSET]; /* Space to build offset */
+ unsigned char outbuf[BUFFER_SIZE]; /* Encoded alaw, two nibbles to a word */
+ int tail;
+};
+
+/*
+ * Private workspace for translating alaw signals to signed linear.
+ */
+
+struct alaw_decoder_pvt
+{
+ struct ast_frame f;
+ char offset[AST_FRIENDLY_OFFSET]; /* Space to build offset */
+ short outbuf[BUFFER_SIZE]; /* Decoded signed linear values */
+ int tail;
+};
+
+/*
+ * alawToLin_New
+ * Create a new instance of alaw_decoder_pvt.
+ *
+ * Results:
+ * Returns a pointer to the new instance.
+ *
+ * Side effects:
+ * None.
+ */
+
+static struct ast_translator_pvt *
+alawtolin_new ()
+{
+ struct alaw_decoder_pvt *tmp;
+ tmp = malloc (sizeof (struct alaw_decoder_pvt));
+ if (tmp)
+ {
+ memset(tmp, 0, sizeof(*tmp));
+ tmp->tail = 0;
+ localusecnt++;
+ ast_update_use_count ();
+ }
+ return (struct ast_translator_pvt *) tmp;
+}
+
+/*
+ * LinToalaw_New
+ * Create a new instance of alaw_encoder_pvt.
+ *
+ * Results:
+ * Returns a pointer to the new instance.
+ *
+ * Side effects:
+ * None.
+ */
+
+static struct ast_translator_pvt *
+lintoalaw_new ()
+{
+ struct alaw_encoder_pvt *tmp;
+ tmp = malloc (sizeof (struct alaw_encoder_pvt));
+ if (tmp)
+ {
+ memset(tmp, 0, sizeof(*tmp));
+ localusecnt++;
+ ast_update_use_count ();
+ tmp->tail = 0;
+ }
+ return (struct ast_translator_pvt *) tmp;
+}
+
+/*
+ * alawToLin_FrameIn
+ * Fill an input buffer with packed 4-bit alaw values if there is room
+ * left.
+ *
+ * Results:
+ * Foo
+ *
+ * Side effects:
+ * tmp->tail is the number of packed values in the buffer.
+ */
+
+static int
+alawtolin_framein (struct ast_translator_pvt *pvt, struct ast_frame *f)
+{
+ struct alaw_decoder_pvt *tmp = (struct alaw_decoder_pvt *) pvt;
+ int x;
+ unsigned char *b;
+
+ if ((tmp->tail + f->datalen) * 2 > sizeof(tmp->outbuf)) {
+ ast_log(LOG_WARNING, "Out of buffer space\n");
+ return -1;
+ }
+
+ /* Reset ssindex and signal to frame's specified values */
+ b = f->data;
+ for (x=0;x<f->datalen;x++)
+ tmp->outbuf[tmp->tail + x] = AST_ALAW(b[x]);
+
+ tmp->tail += f->datalen;
+ return 0;
+}
+
+/*
+ * alawToLin_FrameOut
+ * Convert 4-bit alaw encoded signals to 16-bit signed linear.
+ *
+ * Results:
+ * Converted signals are placed in tmp->f.data, tmp->f.datalen
+ * and tmp->f.timelen are calculated.
+ *
+ * Side effects:
+ * None.
+ */
+
+static struct ast_frame *
+alawtolin_frameout (struct ast_translator_pvt *pvt)
+{
+ struct alaw_decoder_pvt *tmp = (struct alaw_decoder_pvt *) pvt;
+
+ if (!tmp->tail)
+ return NULL;
+
+ tmp->f.frametype = AST_FRAME_VOICE;
+ tmp->f.subclass = AST_FORMAT_SLINEAR;
+ tmp->f.datalen = tmp->tail *2;
+ tmp->f.timelen = tmp->tail / 8;
+ tmp->f.mallocd = 0;
+ tmp->f.offset = AST_FRIENDLY_OFFSET;
+ tmp->f.src = __PRETTY_FUNCTION__;
+ tmp->f.data = tmp->outbuf;
+ tmp->tail = 0;
+ return &tmp->f;
+}
+
+/*
+ * LinToalaw_FrameIn
+ * Fill an input buffer with 16-bit signed linear PCM values.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * tmp->tail is number of signal values in the input buffer.
+ */
+
+static int
+lintoalaw_framein (struct ast_translator_pvt *pvt, struct ast_frame *f)
+{
+ struct alaw_encoder_pvt *tmp = (struct alaw_encoder_pvt *) pvt;
+ int x;
+ short *s;
+ if (tmp->tail + f->datalen/2 >= sizeof(tmp->outbuf))
+ {
+ ast_log (LOG_WARNING, "Out of buffer space\n");
+ return -1;
+ }
+ s = f->data;
+ for (x=0;x<f->datalen/2;x++)
+ tmp->outbuf[x+tmp->tail] = AST_LIN2A(s[x]);
+ tmp->tail += f->datalen/2;
+ return 0;
+}
+
+/*
+ * LinToalaw_FrameOut
+ * Convert a buffer of raw 16-bit signed linear PCM to a buffer
+ * of 4-bit alaw packed two to a byte (Big Endian).
+ *
+ * Results:
+ * Foo
+ *
+ * Side effects:
+ * Leftover inbuf data gets packed, tail gets updated.
+ */
+
+static struct ast_frame *
+lintoalaw_frameout (struct ast_translator_pvt *pvt)
+{
+ struct alaw_encoder_pvt *tmp = (struct alaw_encoder_pvt *) pvt;
+
+ if (tmp->tail) {
+ tmp->f.frametype = AST_FRAME_VOICE;
+ tmp->f.subclass = AST_FORMAT_ALAW;
+ tmp->f.timelen = tmp->tail / 8;
+ tmp->f.mallocd = 0;
+ tmp->f.offset = AST_FRIENDLY_OFFSET;
+ tmp->f.src = __PRETTY_FUNCTION__;
+ tmp->f.data = tmp->outbuf;
+ tmp->f.datalen = tmp->tail;
+ tmp->tail = 0;
+ return &tmp->f;
+ } else return NULL;
+}
+
+
+/*
+ * alawToLin_Sample
+ */
+
+static struct ast_frame *
+alawtolin_sample ()
+{
+ static struct ast_frame f;
+ f.frametype = AST_FRAME_VOICE;
+ f.subclass = AST_FORMAT_ALAW;
+ f.datalen = sizeof (ulaw_slin_ex);
+ f.timelen = sizeof(ulaw_slin_ex) / 8;
+ f.mallocd = 0;
+ f.offset = 0;
+ f.src = __PRETTY_FUNCTION__;
+ f.data = ulaw_slin_ex;
+ return &f;
+}
+
+/*
+ * LinToalaw_Sample
+ */
+
+static struct ast_frame *
+lintoalaw_sample ()
+{
+ static struct ast_frame f;
+ f.frametype = AST_FRAME_VOICE;
+ f.subclass = AST_FORMAT_SLINEAR;
+ f.datalen = sizeof (slin_ulaw_ex);
+ /* Assume 8000 Hz */
+ f.timelen = sizeof (slin_ulaw_ex) / 16;
+ f.mallocd = 0;
+ f.offset = 0;
+ f.src = __PRETTY_FUNCTION__;
+ f.data = slin_ulaw_ex;
+ return &f;
+}
+
+/*
+ * alaw_Destroy
+ * Destroys a private workspace.
+ *
+ * Results:
+ * It's gone!
+ *
+ * Side effects:
+ * None.
+ */
+
+static void
+alaw_destroy (struct ast_translator_pvt *pvt)
+{
+ free (pvt);
+ localusecnt--;
+ ast_update_use_count ();
+}
+
+/*
+ * The complete translator for alawToLin.
+ */
+
+static struct ast_translator alawtolin = {
+ "alawtolin",
+ AST_FORMAT_ALAW,
+ AST_FORMAT_SLINEAR,
+ alawtolin_new,
+ alawtolin_framein,
+ alawtolin_frameout,
+ alaw_destroy,
+ /* NULL */
+ alawtolin_sample
+};
+
+/*
+ * The complete translator for LinToalaw.
+ */
+
+static struct ast_translator lintoalaw = {
+ "lintoalaw",
+ AST_FORMAT_SLINEAR,
+ AST_FORMAT_ALAW,
+ lintoalaw_new,
+ lintoalaw_framein,
+ lintoalaw_frameout,
+ alaw_destroy,
+ /* NULL */
+ lintoalaw_sample
+};
+
+int
+unload_module (void)
+{
+ int res;
+ ast_pthread_mutex_lock (&localuser_lock);
+ res = ast_unregister_translator (&lintoalaw);
+ if (!res)
+ res = ast_unregister_translator (&alawtolin);
+ if (localusecnt)
+ res = -1;
+ ast_pthread_mutex_unlock (&localuser_lock);
+ return res;
+}
+
+int
+load_module (void)
+{
+ int res;
+ res = ast_register_translator (&alawtolin);
+ if (!res)
+ res = ast_register_translator (&lintoalaw);
+ else
+ ast_unregister_translator (&alawtolin);
+ return res;
+}
+
+/*
+ * Return a description of this module.
+ */
+
+char *
+description (void)
+{
+ return tdesc;
+}
+
+int
+usecount (void)
+{
+ int res;
+ STANDARD_USECOUNT (res);
+ return res;
+}
+
+char *
+key ()
+{
+ return ASTERISK_GPL_KEY;
+}