From: David Vossel <dvossel@digium.com>
Date: Wed, 13 Jul 2011 22:09:34 +0000 (+0000)
Subject: Preserve sample rate quality of wideband mixmonitor recordings.
X-Git-Tag: 10.0.0-beta1~3^2~29
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2a9f8fc6757bf1368f5b3042349163c726a4aa25;p=thirdparty%2Fasterisk.git

Preserve sample rate quality of wideband mixmonitor recordings.

MixMonitor has the ability to record in any file format Asterisk supports,
but the quality of wideband audio is not preserved.  This is because
regardless of the sample rate the call is being recorded in, the audio
is always downsampled to 8khz and then upsampled to whatever wideband
format it is being written as.  This patch resolves this by requesting
the audio from the audiohook in the signed linear format closest to the
sample rate of the format we are writing.  This fix is only possible for
Asterisk 1.10 because audio hooks in 1.8 are not capable of wideband
audio.

Review: https://reviewboard.asterisk.org/r/1314/



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.10@328120 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/apps/app_mixmonitor.c b/apps/app_mixmonitor.c
index 29463e2536..05798ffa33 100644
--- a/apps/app_mixmonitor.c
+++ b/apps/app_mixmonitor.c
@@ -47,6 +47,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/channel.h"
 #include "asterisk/autochan.h"
 #include "asterisk/manager.h"
+#include "asterisk/mod_format.h"
 
 /*** DOCUMENTATION
 	<application name="MixMonitor" language="en_US">
@@ -225,6 +226,8 @@ struct mixmonitor_ds {
 	struct ast_filestream *fs_write;
 
 	struct ast_audiohook *audiohook;
+
+	unsigned int samp_rate;
 };
 
 /*!
@@ -334,7 +337,7 @@ static void mixmonitor_save_prep(struct mixmonitor *mixmonitor, char *filename,
 		if (!*fs && !*errflag && !mixmonitor->mixmonitor_ds->fs_quit) {
 			*oflags = O_CREAT | O_WRONLY;
 			*oflags |= ast_test_flag(mixmonitor, MUXFLAG_APPEND) ? O_APPEND : O_TRUNC;
-			
+
 			last_slash = strrchr(filename, '/');
 
 			if ((ext = strrchr(filename, '.')) && (ext > last_slash)) {
@@ -346,6 +349,9 @@ static void mixmonitor_save_prep(struct mixmonitor *mixmonitor, char *filename,
 			if (!(*fs = ast_writefile(filename, ext, NULL, *oflags, 0, 0666))) {
 				ast_log(LOG_ERROR, "Cannot open %s.%s\n", filename, ext);
 				*errflag = 1;
+			} else {
+				struct ast_filestream *tmp = *fs;
+				mixmonitor->mixmonitor_ds->samp_rate = MAX(mixmonitor->mixmonitor_ds->samp_rate, ast_format_rate(&tmp->fmt->format));
 			}
 		}
 	}
@@ -363,13 +369,22 @@ static void *mixmonitor_thread(void *obj)
 	int errflag = 0;
 	struct ast_format format_slin;
 
-	ast_format_set(&format_slin, AST_FORMAT_SLINEAR, 0);
 	ast_verb(2, "Begin MixMonitor Recording %s\n", mixmonitor->name);
 
 	fs = &mixmonitor->mixmonitor_ds->fs;
 	fs_read = &mixmonitor->mixmonitor_ds->fs_read;
 	fs_write = &mixmonitor->mixmonitor_ds->fs_write;
 
+	ast_mutex_lock(&mixmonitor->mixmonitor_ds->lock);
+	mixmonitor_save_prep(mixmonitor, mixmonitor->filename, fs, &oflags, &errflag);
+	mixmonitor_save_prep(mixmonitor, mixmonitor->filename_read, fs_read, &oflags, &errflag);
+	mixmonitor_save_prep(mixmonitor, mixmonitor->filename_write, fs_write, &oflags, &errflag);
+
+	ast_format_set(&format_slin, ast_format_slin_by_rate(mixmonitor->mixmonitor_ds->samp_rate), 0);
+
+	ast_mutex_unlock(&mixmonitor->mixmonitor_ds->lock);
+
+
 	/* The audiohook must enter and exit the loop locked */
 	ast_audiohook_lock(&mixmonitor->audiohook);
 	while (mixmonitor->audiohook.status == AST_AUDIOHOOK_STATUS_RUNNING && !mixmonitor->mixmonitor_ds->fs_quit) {
@@ -393,9 +408,6 @@ static void *mixmonitor_thread(void *obj)
 
 		if (!ast_test_flag(mixmonitor, MUXFLAG_BRIDGED) || (mixmonitor->autochan->chan && ast_bridged_channel(mixmonitor->autochan->chan))) {
 			ast_mutex_lock(&mixmonitor->mixmonitor_ds->lock);
-			mixmonitor_save_prep(mixmonitor, mixmonitor->filename, fs, &oflags, &errflag);
-			mixmonitor_save_prep(mixmonitor, mixmonitor->filename_read, fs_read, &oflags, &errflag);
-			mixmonitor_save_prep(mixmonitor, mixmonitor->filename_write, fs_write, &oflags, &errflag);
 
 			/* Write out the frame(s) */
 			if ((*fs_read) && (fr_read)) {
@@ -484,6 +496,8 @@ static int setup_mixmonitor_ds(struct mixmonitor *mixmonitor, struct ast_channel
 		return -1;
 	}
 
+
+	mixmonitor_ds->samp_rate = 8000;
 	mixmonitor_ds->audiohook = &mixmonitor->audiohook;
 	datastore->data = mixmonitor_ds;