[FFmpeg-devel] [PATCH] amerge audio filter [WIP]
Nicolas George
nicolas.george at normalesup.org
Sun Nov 6 21:32:55 CET 2011
Signed-off-by: Nicolas George <nicolas.george at normalesup.org>
---
libavfilter/Makefile | 1 +
libavfilter/af_amerge.c | 177 ++++++++++++++++++++++++++++++++++++++++++++++
libavfilter/allfilters.c | 1 +
3 files changed, 179 insertions(+), 0 deletions(-)
create mode 100644 libavfilter/af_amerge.c
This is early work in progress, just in case someone would happen to work on
the same thing at the same time, and because I will not be able to come back
on it for a few days.
The following command works for me:
./ffmpeg_g -f lavfi -i 'amovie=1.wav [b] ; amovie=2.mp3 [a] ;
[a] [b] amerge, pan=5.1:1:0:0:0:0:0:0:1:0:0:0:0:0:0:0:0:1:0:0:0:0:0:0:1' \
-f alsa surround51
(On the other hand, amovie segfaults on Ogg Vorbis files.)
Regards,
--
Nicolas George
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index aeb5575..3185666 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -25,6 +25,7 @@ OBJS-$(CONFIG_AVCODEC) += avcodec.o
OBJS-$(CONFIG_ACONVERT_FILTER) += af_aconvert.o
OBJS-$(CONFIG_AFORMAT_FILTER) += af_aformat.o
+OBJS-$(CONFIG_AMERGE_FILTER) += af_amerge.o
OBJS-$(CONFIG_ANULL_FILTER) += af_anull.o
OBJS-$(CONFIG_ARESAMPLE_FILTER) += af_aresample.o
OBJS-$(CONFIG_ASHOWINFO_FILTER) += af_ashowinfo.o
diff --git a/libavfilter/af_amerge.c b/libavfilter/af_amerge.c
new file mode 100644
index 0000000..37a6a8d
--- /dev/null
+++ b/libavfilter/af_amerge.c
@@ -0,0 +1,177 @@
+/*
+ * Copyright (C) 2011 Nicolas George <nicolas.george at normalesup.org>
+ *
+ * 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 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
+ * Audio merging filter
+ */
+
+#include <stdlib.h>
+#include "libavcodec/avcodec.h"
+#include "libavutil/avstring.h"
+#include "libswresample/swresample.h" // only for SWR_CH_MAX
+#include "avfilter.h"
+#include "internal.h"
+
+struct amerge_context {
+ AVFilterBufferRef *inbuf[2];
+ int route[SWR_CH_MAX];
+ int nb_channels_in[2];
+ int inpos[2];
+};
+
+static av_cold int init(AVFilterContext *ctx, const char *args0, void *opaque)
+{
+ return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ struct amerge_context *am = ctx->priv;
+ int64_t inlayout[2], outlayout;
+ const int packing_fmts[] = { AVFILTER_PACKED, -1};
+ AVFilterFormats *formats;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ if (!ctx->inputs[i]->in_chlayouts ||
+ !ctx->inputs[i]->in_chlayouts->format_count) {
+ av_log(ctx, AV_LOG_ERROR,
+ "no channel layout for input %d\n", i + 1);
+ return AVERROR(EINVAL);
+ }
+ inlayout[i] = ctx->inputs[i]->in_chlayouts->formats[0];
+ if (ctx->inputs[i]->in_chlayouts->format_count > 1) {
+ char buf[256];
+ av_get_channel_layout_string(buf, sizeof(buf), 0, inlayout[i]);
+ av_log(ctx, AV_LOG_INFO, "using \"%s\" for input %d\n", buf, i + 1);
+ }
+ am->nb_channels_in[i] = av_get_channel_layout_nb_channels(inlayout[i]);
+ }
+ if (inlayout[0] & inlayout[1]) {
+ av_log(ctx, AV_LOG_WARNING,
+ "inputs overlap: output layout will be meaningless\n");
+ for (i = 0; i < am->nb_channels_in[0]; i++)
+ am->route[i] = i;
+ for (i = 0; i < am->nb_channels_in[1]; i++)
+ am->route[i + am->nb_channels_in[0]] = i;
+ outlayout = av_get_default_channel_layout(am->nb_channels_in[0] + am->nb_channels_in[1]);
+ if (!outlayout)
+ outlayout = ((int64_t)1 << (am->nb_channels_in[0] + am->nb_channels_in[1])) - 1;
+ } else {
+ /* TODO */
+ return AVERROR(EINVAL);
+ }
+ avfilter_set_common_sample_formats(ctx, avfilter_make_all_formats(AVMEDIA_TYPE_AUDIO));
+ avfilter_set_common_packing_formats(ctx, avfilter_make_format_list(packing_fmts));
+ for (i = 0; i < 2; i++) {
+ formats = NULL;
+ avfilter_add_format(&formats, inlayout[i]);
+ avfilter_formats_ref(formats, &ctx->inputs[i]->out_chlayouts);
+ }
+ formats = NULL;
+ avfilter_add_format(&formats, outlayout);
+ avfilter_formats_ref(formats, &ctx->outputs[0]->in_chlayouts);
+ return 0;
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+ return 0;
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ struct amerge_context *am = ctx->priv;
+ int i;
+
+ for (i = 0; i < 2; i++)
+ if (!am->inbuf[i])
+ avfilter_request_frame(ctx->inputs[i]);
+ return 0;
+}
+
+static void filter_samples(AVFilterLink *inlink, AVFilterBufferRef *insamples)
+{
+ AVFilterContext *ctx = inlink->dst;
+ struct amerge_context *am = ctx->priv;
+ int in_no = inlink == ctx->inputs[1];
+ int nb_samples, i, s, c, *route;
+ AVFilterBufferRef *outsamples;
+ int16_t *ins[2], *outs;
+
+ am->inbuf[in_no] = avfilter_ref_buffer(insamples, AV_PERM_READ);
+ am->inpos[in_no] = 0;
+ if (!am->inbuf[!in_no])
+ return;
+ nb_samples = FFMIN(am->inbuf[0]->audio->nb_samples - am->inpos[0],
+ am->inbuf[1]->audio->nb_samples - am->inpos[1]);
+ outsamples = avfilter_get_audio_buffer(ctx->outputs[0], AV_PERM_WRITE,
+ nb_samples);
+ outs = (int16_t *)outsamples->data[0];
+ for (i = 0; i < 2; i++)
+ ins[i] = (int16_t *)am->inbuf[i]->data[0] +
+ am->nb_channels_in[i] * am->inpos[i];
+ for (s = 0; s < nb_samples; s++) {
+ route = am->route;
+ for (i = 0; i < 2; i++) {
+ for (c = 0; c < am->nb_channels_in[i]; c++)
+ *(outs++) = ins[i][*(route++)];
+ ins[i] += am->nb_channels_in[i];
+ }
+ }
+ for (i = 0; i < 2; i++) {
+ am->inpos[i] += nb_samples;
+ if (am->inpos[i] == am->inbuf[i]->audio->nb_samples) {
+ avfilter_unref_buffer(am->inbuf[i]);
+ am->inbuf[i] = 0;
+ }
+ }
+ avfilter_filter_samples(ctx->outputs[0], outsamples);
+}
+
+AVFilter avfilter_af_amerge = {
+ .name = "amerge",
+ .description = NULL_IF_CONFIG_SMALL("Merge two audio streams into a single multi-channel stream"),
+ .priv_size = sizeof(struct amerge_context),
+ .init = init,
+ .query_formats = query_formats,
+
+ .inputs = (const AVFilterPad[]) {
+ { .name = "in1",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .filter_samples = filter_samples,
+ .min_perms = AV_PERM_READ, },
+ { .name = "in2",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .filter_samples = filter_samples,
+ .min_perms = AV_PERM_READ, },
+ { .name = NULL}
+ },
+ .outputs = (const AVFilterPad[]) {
+ { .name = "default",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .config_props = config_output,
+ .request_frame = request_frame, },
+ { .name = NULL}
+ },
+};
+
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index d36ede7..daee7d9 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -36,6 +36,7 @@ void avfilter_register_all(void)
REGISTER_FILTER (ACONVERT, aconvert, af);
REGISTER_FILTER (AFORMAT, aformat, af);
+ REGISTER_FILTER (AMERGE, amerge, af);
REGISTER_FILTER (ANULL, anull, af);
REGISTER_FILTER (ARESAMPLE, aresample, af);
REGISTER_FILTER (ASHOWINFO, ashowinfo, af);
--
1.7.7.1
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