[FFmpeg-devel] [PATCH] avfilter: split asrc_anullsrc

Michael Niedermayer michaelni at gmx.at
Sat Mar 16 18:54:06 CET 2013


asrc_anullsrc is renamed to asrc_asilencesrc
and asrc_anullsrc is taken from 4750b05d67fd87263cb767b896e1cf55713a39de
This makes our anullsrc match the one from the fork. And should
improve compatibility between them.

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
---
 doc/filters.texi               |    6 +-
 libavfilter/Makefile           |    1 +
 libavfilter/allfilters.c       |    1 +
 libavfilter/asrc_anullsrc.c    |   94 +--------------------------
 libavfilter/asrc_asilencesrc.c |  141 ++++++++++++++++++++++++++++++++++++++++
 5 files changed, 149 insertions(+), 94 deletions(-)
 create mode 100644 libavfilter/asrc_asilencesrc.c

diff --git a/doc/filters.texi b/doc/filters.texi
index 0dbec8e..1080e3f 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -1511,7 +1511,7 @@ aevalsrc="0.1*sin(2*PI*(360-2.5/2)*t) : 0.1*sin(2*PI*(360+2.5/2)*t)"
 
 @end itemize
 
- at section anullsrc
+ at section asilencesrc
 
 Null audio source, return unprocessed audio frames. It is mainly useful
 as a template and to be employed in analysis / debugging tools, or as
@@ -1549,13 +1549,13 @@ Set the number of samples per requested frames.
 @item
 Set the sample rate to 48000 Hz and the channel layout to AV_CH_LAYOUT_MONO.
 @example
-anullsrc=r=48000:cl=4
+asilencesrc=r=48000:cl=4
 @end example
 
 @item
 Do the same operation with a more obvious syntax:
 @example
-anullsrc=r=48000:cl=mono
+asilencesrc=r=48000:cl=mono
 @end example
 @end itemize
 
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 2758c8e..acd9b4e 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -89,6 +89,7 @@ OBJS-$(CONFIG_VOLUMEDETECT_FILTER)           += af_volumedetect.o
 
 OBJS-$(CONFIG_AEVALSRC_FILTER)               += asrc_aevalsrc.o
 OBJS-$(CONFIG_ANULLSRC_FILTER)               += asrc_anullsrc.o
+OBJS-$(CONFIG_ASILENCESRC_FILTER)            += asrc_asilencesrc.o
 OBJS-$(CONFIG_FLITE_FILTER)                  += asrc_flite.o
 
 OBJS-$(CONFIG_ANULLSINK_FILTER)              += asink_anullsink.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 086e6c9..04b46da 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -85,6 +85,7 @@ void avfilter_register_all(void)
 
     REGISTER_FILTER(AEVALSRC,       aevalsrc,       asrc);
     REGISTER_FILTER(ANULLSRC,       anullsrc,       asrc);
+    REGISTER_FILTER(ASILENCESRC,    asilencesrc,    asrc);
     REGISTER_FILTER(FLITE,          flite,          asrc);
 
     REGISTER_FILTER(ANULLSINK,      anullsink,      asink);
diff --git a/libavfilter/asrc_anullsrc.c b/libavfilter/asrc_anullsrc.c
index f8e6ac5..956de83 100644
--- a/libavfilter/asrc_anullsrc.c
+++ b/libavfilter/asrc_anullsrc.c
@@ -1,7 +1,4 @@
 /*
- * Copyright 2010 S.N. Hemanth Meenakshisundaram <smeenaks ucsd edu>
- * Copyright 2010 Stefano Sabatini <stefano.sabatini-lala poste it>
- *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
@@ -29,99 +26,18 @@
 
 #include "libavutil/channel_layout.h"
 #include "libavutil/internal.h"
-#include "libavutil/opt.h"
-#include "audio.h"
 #include "avfilter.h"
 #include "internal.h"
 
-typedef struct {
-    const AVClass *class;
-    char   *channel_layout_str;
-    uint64_t channel_layout;
-    char   *sample_rate_str;
-    int     sample_rate;
-    int nb_samples;             ///< number of samples per requested frame
-    int64_t pts;
-} ANullContext;
-
-#define OFFSET(x) offsetof(ANullContext, x)
-#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
-
-static const AVOption anullsrc_options[]= {
-    { "channel_layout", "set channel_layout", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, FLAGS },
-    { "cl",             "set channel_layout", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, FLAGS },
-    { "sample_rate",    "set sample rate",    OFFSET(sample_rate_str)   , AV_OPT_TYPE_STRING, {.str = "44100"}, 0, 0, FLAGS },
-    { "r",              "set sample rate",    OFFSET(sample_rate_str)   , AV_OPT_TYPE_STRING, {.str = "44100"}, 0, 0, FLAGS },
-    { "nb_samples",     "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 0, INT_MAX, FLAGS },
-    { "n",              "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 0, INT_MAX, FLAGS },
-    { NULL },
-};
-
-AVFILTER_DEFINE_CLASS(anullsrc);
-
-static int init(AVFilterContext *ctx, const char *args)
-{
-    ANullContext *null = ctx->priv;
-    int ret;
-
-    null->class = &anullsrc_class;
-    av_opt_set_defaults(null);
-
-    if ((ret = (av_set_options_string(null, args, "=", ":"))) < 0)
-        return ret;
-
-    if ((ret = ff_parse_sample_rate(&null->sample_rate,
-                                     null->sample_rate_str, ctx)) < 0)
-        return ret;
-
-    if ((ret = ff_parse_channel_layout(&null->channel_layout,
-                                        null->channel_layout_str, ctx)) < 0)
-        return ret;
-
-    return 0;
-}
-
-static int config_props(AVFilterLink *outlink)
-{
-    ANullContext *null = outlink->src->priv;
-    char buf[128];
-    int chans_nb;
-
-    outlink->sample_rate = null->sample_rate;
-    outlink->channel_layout = null->channel_layout;
-
-    chans_nb = av_get_channel_layout_nb_channels(null->channel_layout);
-    av_get_channel_layout_string(buf, sizeof(buf), chans_nb, null->channel_layout);
-    av_log(outlink->src, AV_LOG_VERBOSE,
-           "sample_rate:%d channel_layout:'%s' nb_samples:%d\n",
-           null->sample_rate, buf, null->nb_samples);
-
-    return 0;
-}
-
-static int request_frame(AVFilterLink *outlink)
+static int request_frame(AVFilterLink *link)
 {
-    int ret;
-    ANullContext *null = outlink->src->priv;
-    AVFrame *samplesref;
-
-    samplesref = ff_get_audio_buffer(outlink, null->nb_samples);
-    samplesref->pts = null->pts;
-    samplesref->channel_layout = null->channel_layout;
-    samplesref->sample_rate = outlink->sample_rate;
-
-    ret = ff_filter_frame(outlink, av_frame_clone(samplesref));
-    av_frame_free(&samplesref);
-
-    null->pts += null->nb_samples;
-    return ret;
+    return AVERROR_EOF;
 }
 
 static const AVFilterPad avfilter_asrc_anullsrc_outputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_AUDIO,
-        .config_props  = config_props,
         .request_frame = request_frame,
     },
     { NULL }
@@ -129,13 +45,9 @@ static const AVFilterPad avfilter_asrc_anullsrc_outputs[] = {
 
 AVFilter avfilter_asrc_anullsrc = {
     .name        = "anullsrc",
-    .description = NULL_IF_CONFIG_SMALL("Null audio source, return empty audio frames."),
-
-    .init        = init,
-    .priv_size   = sizeof(ANullContext),
+    .description = NULL_IF_CONFIG_SMALL("Null audio source, never return audio frames."),
 
     .inputs      = NULL,
 
     .outputs     = avfilter_asrc_anullsrc_outputs,
-    .priv_class = &anullsrc_class,
 };
diff --git a/libavfilter/asrc_asilencesrc.c b/libavfilter/asrc_asilencesrc.c
new file mode 100644
index 0000000..e768ede
--- /dev/null
+++ b/libavfilter/asrc_asilencesrc.c
@@ -0,0 +1,141 @@
+/*
+ * Copyright 2010 S.N. Hemanth Meenakshisundaram <smeenaks ucsd edu>
+ * Copyright 2010 Stefano Sabatini <stefano.sabatini-lala poste it>
+ *
+ * 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
+ * silence audio source
+ */
+
+#include <inttypes.h>
+#include <stdio.h>
+
+#include "libavutil/channel_layout.h"
+#include "libavutil/internal.h"
+#include "libavutil/opt.h"
+#include "audio.h"
+#include "avfilter.h"
+#include "internal.h"
+
+typedef struct {
+    const AVClass *class;
+    char   *channel_layout_str;
+    uint64_t channel_layout;
+    char   *sample_rate_str;
+    int     sample_rate;
+    int nb_samples;             ///< number of samples per requested frame
+    int64_t pts;
+} ANullContext;
+
+#define OFFSET(x) offsetof(ANullContext, x)
+#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption asilencesrc_options[]= {
+    { "channel_layout", "set channel_layout", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, FLAGS },
+    { "cl",             "set channel_layout", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, FLAGS },
+    { "sample_rate",    "set sample rate",    OFFSET(sample_rate_str)   , AV_OPT_TYPE_STRING, {.str = "44100"}, 0, 0, FLAGS },
+    { "r",              "set sample rate",    OFFSET(sample_rate_str)   , AV_OPT_TYPE_STRING, {.str = "44100"}, 0, 0, FLAGS },
+    { "nb_samples",     "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 0, INT_MAX, FLAGS },
+    { "n",              "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 0, INT_MAX, FLAGS },
+    { NULL },
+};
+
+AVFILTER_DEFINE_CLASS(asilencesrc);
+
+static int init(AVFilterContext *ctx, const char *args)
+{
+    ANullContext *silence = ctx->priv;
+    int ret;
+
+    silence->class = &asilencesrc_class;
+    av_opt_set_defaults(silence);
+
+    if ((ret = (av_set_options_string(silence, args, "=", ":"))) < 0)
+        return ret;
+
+    if ((ret = ff_parse_sample_rate(&silence->sample_rate,
+                                     silence->sample_rate_str, ctx)) < 0)
+        return ret;
+
+    if ((ret = ff_parse_channel_layout(&silence->channel_layout,
+                                        silence->channel_layout_str, ctx)) < 0)
+        return ret;
+
+    return 0;
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+    ANullContext *silence = outlink->src->priv;
+    char buf[128];
+    int chans_nb;
+
+    outlink->sample_rate = silence->sample_rate;
+    outlink->channel_layout = silence->channel_layout;
+
+    chans_nb = av_get_channel_layout_nb_channels(silence->channel_layout);
+    av_get_channel_layout_string(buf, sizeof(buf), chans_nb, silence->channel_layout);
+    av_log(outlink->src, AV_LOG_VERBOSE,
+           "sample_rate:%d channel_layout:'%s' nb_samples:%d\n",
+           silence->sample_rate, buf, silence->nb_samples);
+
+    return 0;
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+    int ret;
+    ANullContext *silence = outlink->src->priv;
+    AVFrame *samplesref;
+
+    samplesref = ff_get_audio_buffer(outlink, silence->nb_samples);
+    samplesref->pts = silence->pts;
+    samplesref->channel_layout = silence->channel_layout;
+    samplesref->sample_rate = outlink->sample_rate;
+
+    ret = ff_filter_frame(outlink, av_frame_clone(samplesref));
+    av_frame_free(&samplesref);
+
+    silence->pts += silence->nb_samples;
+    return ret;
+}
+
+static const AVFilterPad avfilter_asrc_asilencesrc_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_AUDIO,
+        .config_props  = config_props,
+        .request_frame = request_frame,
+    },
+    { NULL }
+};
+
+AVFilter avfilter_asrc_asilencesrc = {
+    .name        = "asilencesrc",
+    .description = NULL_IF_CONFIG_SMALL("Silence audio source, return silent audio frames."),
+
+    .init        = init,
+    .priv_size   = sizeof(ANullContext),
+
+    .inputs      = NULL,
+
+    .outputs     = avfilter_asrc_asilencesrc_outputs,
+    .priv_class = &asilencesrc_class,
+};
-- 
1.7.9.5



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