[FFmpeg-cvslog] r25188 - in trunk: doc/filters.texi libavfilter/Makefile libavfilter/allfilters.c libavfilter/asrc_anullsrc.c libavfilter/avfilter.h
stefano
subversion
Sat Sep 25 03:56:58 CEST 2010
Author: stefano
Date: Sat Sep 25 03:56:58 2010
New Revision: 25188
Log:
Add asrc_anullsrc - null audio source.
Based on a patch by "S.N. Hemanth Meenakshisundaram" smeenaks!ucsd!edu.
Added:
trunk/libavfilter/asrc_anullsrc.c
Modified:
trunk/doc/filters.texi
trunk/libavfilter/Makefile
trunk/libavfilter/allfilters.c
trunk/libavfilter/avfilter.h
Modified: trunk/doc/filters.texi
==============================================================================
--- trunk/doc/filters.texi Sat Sep 25 03:32:02 2010 (r25187)
+++ trunk/doc/filters.texi Sat Sep 25 03:56:58 2010 (r25188)
@@ -14,6 +14,40 @@ Pass the audio source unchanged to the o
@c man end AUDIO FILTERS
+ at chapter Audio Sources
+ at c man begin AUDIO SOURCES
+
+Below is a description of the currently available audio sources.
+
+ at section anullsrc
+
+Null audio source, never return audio frames. It is mainly useful as a
+template and to be employed in analysis / debugging tools.
+
+It accepts as optional parameter a string of the form
+ at var{sample_rate}:@var{channel_layout}.
+
+ at var{sample_rate} specify the sample rate, and defaults to 44100.
+
+ at var{channel_layout} specify the channel layout, and can be either an
+integer or a string representing a channel layout. The default value
+of @var{channel_layout} is 3, which corresponds to CH_LAYOUT_STEREO.
+
+Check the channel_layout_map definition in
+ at file{libavcodec/audioconvert.c} for the correspondance between string
+and channel layout values.
+
+Follow some examples:
+ at example
+# set the sample rate to 48000 Hz and the channel layout to CH_LAYOUT_MONO.
+anullsrc=48000:4
+
+# same as
+anullsrc=48000:mono
+ at end example
+
+ at c man end AUDIO SOURCES
+
@chapter Video Filters
@c man begin VIDEO FILTERS
Modified: trunk/libavfilter/Makefile
==============================================================================
--- trunk/libavfilter/Makefile Sat Sep 25 03:32:02 2010 (r25187)
+++ trunk/libavfilter/Makefile Sat Sep 25 03:56:58 2010 (r25188)
@@ -16,6 +16,8 @@ OBJS = allfilters.o
OBJS-$(CONFIG_ANULL_FILTER) += af_anull.o
+OBJS-$(CONFIG_ANULLSRC_FILTER) += asrc_anullsrc.o
+
OBJS-$(CONFIG_ASPECT_FILTER) += vf_aspect.o
OBJS-$(CONFIG_CROP_FILTER) += vf_crop.o
OBJS-$(CONFIG_FIFO_FILTER) += vf_fifo.o
Modified: trunk/libavfilter/allfilters.c
==============================================================================
--- trunk/libavfilter/allfilters.c Sat Sep 25 03:32:02 2010 (r25187)
+++ trunk/libavfilter/allfilters.c Sat Sep 25 03:56:58 2010 (r25188)
@@ -36,6 +36,8 @@ void avfilter_register_all(void)
REGISTER_FILTER (ANULL, anull, af);
+ REGISTER_FILTER (ANULLSRC, anullsrc, asrc);
+
REGISTER_FILTER (ASPECT, aspect, vf);
REGISTER_FILTER (CROP, crop, vf);
REGISTER_FILTER (FIFO, fifo, vf);
Added: trunk/libavfilter/asrc_anullsrc.c
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ trunk/libavfilter/asrc_anullsrc.c Sat Sep 25 03:56:58 2010 (r25188)
@@ -0,0 +1,96 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * null audio source
+ */
+
+#include "avfilter.h"
+#include "libavcodec/audioconvert.h"
+
+typedef struct {
+ int64_t channel_layout;
+ int64_t sample_rate;
+} ANullContext;
+
+static int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+ ANullContext *priv = ctx->priv;
+ char channel_layout_str[128] = "";
+
+ priv->sample_rate = 44100;
+ priv->channel_layout = CH_LAYOUT_STEREO;
+
+ if (args)
+ sscanf(args, "%"PRId64":%s", &priv->sample_rate, channel_layout_str);
+
+ if (priv->sample_rate < 0) {
+ av_log(ctx, AV_LOG_ERROR, "Invalid negative sample rate: %"PRId64"\n", priv->sample_rate);
+ return AVERROR(EINVAL);
+ }
+
+ if (*channel_layout_str)
+ if (!(priv->channel_layout = avcodec_get_channel_layout(channel_layout_str))
+ && sscanf(channel_layout_str, "%"PRId64, &priv->channel_layout) != 1) {
+ av_log(ctx, AV_LOG_ERROR, "Invalid value '%s' for channel layout\n",
+ channel_layout_str);
+ return AVERROR(EINVAL);
+ }
+
+ return 0;
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+ ANullContext *priv = outlink->src->priv;
+ char buf[128];
+ int chans_nb;
+
+ outlink->sample_rate = priv->sample_rate;
+ outlink->channel_layout = priv->channel_layout;
+
+ chans_nb = avcodec_channel_layout_num_channels(priv->channel_layout);
+ avcodec_get_channel_layout_string(buf, sizeof(buf), chans_nb, priv->channel_layout);
+ av_log(outlink->src, AV_LOG_INFO,
+ "sample_rate:%"PRId64 " channel_layout:%"PRId64 " channel_layout_description:'%s'\n",
+ priv->sample_rate, priv->channel_layout, buf);
+
+ return 0;
+}
+
+static int request_frame(AVFilterLink *link)
+{
+ return -1;
+}
+
+AVFilter avfilter_asrc_anullsrc = {
+ .name = "anullsrc",
+ .description = NULL_IF_CONFIG_SMALL("Null audio source, never return audio frames."),
+
+ .init = init,
+ .priv_size = sizeof(ANullContext),
+
+ .inputs = (AVFilterPad[]) {{ .name = NULL}},
+
+ .outputs = (AVFilterPad[]) {{ .name = "default",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .config_props = config_props,
+ .request_frame = request_frame, },
+ { .name = NULL}},
+};
Modified: trunk/libavfilter/avfilter.h
==============================================================================
--- trunk/libavfilter/avfilter.h Sat Sep 25 03:32:02 2010 (r25187)
+++ trunk/libavfilter/avfilter.h Sat Sep 25 03:56:58 2010 (r25188)
@@ -25,7 +25,7 @@
#include "libavutil/avutil.h"
#define LIBAVFILTER_VERSION_MAJOR 1
-#define LIBAVFILTER_VERSION_MINOR 42
+#define LIBAVFILTER_VERSION_MINOR 43
#define LIBAVFILTER_VERSION_MICRO 0
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
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