[FFmpeg-cvslog] avcodec: Add a RFC 3389 comfort noise codec
Martin Storsjö
git at videolan.org
Tue Oct 30 15:16:38 CET 2012
ffmpeg | branch: master | Martin Storsjö <martin at martin.st> | Tue Oct 23 00:02:41 2012 +0300| [9b500b8f6c9806f3979f9d1fb874b7f4a802c656] | committer: Martin Storsjö
avcodec: Add a RFC 3389 comfort noise codec
This isn't too useful as a normal codec, but can be used in
voip style applications. The decoder updates the noise
generator parameters when a packet is given to it for decoding,
but if called with an empty packet, it generates more noise
according to the last parameters.
Signed-off-by: Martin Storsjö <martin at martin.st>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=9b500b8f6c9806f3979f9d1fb874b7f4a802c656
---
configure | 1 +
libavcodec/Makefile | 2 +
libavcodec/allcodecs.c | 1 +
libavcodec/avcodec.h | 1 +
libavcodec/cngdec.c | 162 +++++++++++++++++++++++++++++++++++++++++++++++
libavcodec/cngenc.c | 116 +++++++++++++++++++++++++++++++++
libavcodec/codec_desc.c | 7 ++
libavcodec/version.h | 2 +-
8 files changed, 291 insertions(+), 1 deletion(-)
diff --git a/configure b/configure
index 1a006be..2abc465 100755
--- a/configure
+++ b/configure
@@ -1440,6 +1440,7 @@ atrac3_decoder_select="mdct"
binkaudio_dct_decoder_select="mdct rdft dct sinewin"
binkaudio_rdft_decoder_select="mdct rdft sinewin"
cavs_decoder_select="golomb mpegvideo"
+comfortnoise_encoder_select="lpc"
cook_decoder_select="mdct sinewin"
cscd_decoder_select="lzo"
cscd_decoder_suggest="zlib"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index d8c853a..4d14aea 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -129,6 +129,8 @@ OBJS-$(CONFIG_CLJR_DECODER) += cljr.o
OBJS-$(CONFIG_CLJR_ENCODER) += cljr.o
OBJS-$(CONFIG_CLLC_DECODER) += cllc.o
OBJS-$(CONFIG_COOK_DECODER) += cook.o
+OBJS-$(CONFIG_COMFORTNOISE_DECODER) += cngdec.o celp_filters.o
+OBJS-$(CONFIG_COMFORTNOISE_ENCODER) += cngenc.o
OBJS-$(CONFIG_CSCD_DECODER) += cscd.o
OBJS-$(CONFIG_CYUV_DECODER) += cyuv.o
OBJS-$(CONFIG_DCA_DECODER) += dcadec.o dca.o dcadsp.o \
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index b175fbb..e5fb351 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -91,6 +91,7 @@ void avcodec_register_all(void)
REGISTER_DECODER (CINEPAK, cinepak);
REGISTER_ENCDEC (CLJR, cljr);
REGISTER_DECODER (CLLC, cllc);
+ REGISTER_ENCDEC (COMFORTNOISE, comfortnoise);
REGISTER_DECODER (CSCD, cscd);
REGISTER_DECODER (CYUV, cyuv);
REGISTER_DECODER (DFA, dfa);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index c505a92..d6a4e4d 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -406,6 +406,7 @@ enum AVCodecID {
AV_CODEC_ID_IAC,
AV_CODEC_ID_ILBC,
AV_CODEC_ID_OPUS,
+ AV_CODEC_ID_COMFORT_NOISE,
/* subtitle codecs */
AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
diff --git a/libavcodec/cngdec.c b/libavcodec/cngdec.c
new file mode 100644
index 0000000..c22fd55
--- /dev/null
+++ b/libavcodec/cngdec.c
@@ -0,0 +1,162 @@
+/*
+ * RFC 3389 comfort noise generator
+ * Copyright (c) 2012 Martin Storsjo
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <math.h>
+
+#include "libavutil/common.h"
+#include "avcodec.h"
+#include "celp_filters.h"
+#include "libavutil/lfg.h"
+
+typedef struct CNGContext {
+ AVFrame avframe;
+ float *refl_coef, *target_refl_coef;
+ float *lpc_coef;
+ int order;
+ int energy, target_energy;
+ float *filter_out;
+ float *excitation;
+ AVLFG lfg;
+} CNGContext;
+
+static av_cold int cng_decode_close(AVCodecContext *avctx)
+{
+ CNGContext *p = avctx->priv_data;
+ av_free(p->refl_coef);
+ av_free(p->target_refl_coef);
+ av_free(p->lpc_coef);
+ av_free(p->filter_out);
+ av_free(p->excitation);
+ return 0;
+}
+
+static av_cold int cng_decode_init(AVCodecContext *avctx)
+{
+ CNGContext *p = avctx->priv_data;
+
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+ avctx->channels = 1;
+ avctx->sample_rate = 8000;
+
+ avcodec_get_frame_defaults(&p->avframe);
+ avctx->coded_frame = &p->avframe;
+ p->order = 12;
+ avctx->frame_size = 640;
+ p->refl_coef = av_mallocz(p->order * sizeof(*p->refl_coef));
+ p->target_refl_coef = av_mallocz(p->order * sizeof(*p->target_refl_coef));
+ p->lpc_coef = av_mallocz(p->order * sizeof(*p->lpc_coef));
+ p->filter_out = av_mallocz((avctx->frame_size + p->order) *
+ sizeof(*p->filter_out));
+ p->excitation = av_mallocz(avctx->frame_size * sizeof(*p->excitation));
+ if (!p->refl_coef || !p->target_refl_coef || !p->lpc_coef ||
+ !p->filter_out || !p->excitation) {
+ cng_decode_close(avctx);
+ return AVERROR(ENOMEM);
+ }
+
+ av_lfg_init(&p->lfg, 0);
+
+ return 0;
+}
+
+static void make_lpc_coefs(float *lpc, const float *refl, int order)
+{
+ float buf[100];
+ float *next, *cur;
+ int m, i;
+ next = buf;
+ cur = lpc;
+ for (m = 0; m < order; m++) {
+ next[m] = refl[m];
+ for (i = 0; i < m; i++)
+ next[i] = cur[i] + refl[m] * cur[m - i - 1];
+ FFSWAP(float*, next, cur);
+ }
+ if (cur != lpc)
+ memcpy(lpc, cur, sizeof(*lpc) * order);
+}
+
+static int cng_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *avpkt)
+{
+
+ CNGContext *p = avctx->priv_data;
+ int buf_size = avpkt->size;
+ int ret, i;
+ int16_t *buf_out;
+ float e = 1.0;
+ float scaling;
+
+ if (avpkt->size) {
+ float dbov = -avpkt->data[0] / 10.0;
+ p->target_energy = 1081109975 * pow(10, dbov) * 0.75;
+ memset(p->target_refl_coef, 0, sizeof(p->refl_coef));
+ for (i = 0; i < FFMIN(avpkt->size - 1, p->order); i++) {
+ p->target_refl_coef[i] = (avpkt->data[1 + i] - 127) / 128.0;
+ }
+ make_lpc_coefs(p->lpc_coef, p->refl_coef, p->order);
+ }
+
+ p->energy = p->energy / 2 + p->target_energy / 2;
+ for (i = 0; i < p->order; i++)
+ p->refl_coef[i] = 0.6 *p->refl_coef[i] + 0.4 * p->target_refl_coef[i];
+
+ for (i = 0; i < p->order; i++)
+ e *= 1.0 - p->refl_coef[i]*p->refl_coef[i];
+
+ scaling = sqrt(e * p->energy / 1081109975);
+ for (i = 0; i < avctx->frame_size; i++) {
+ int r = (av_lfg_get(&p->lfg) & 0xffff) - 0x8000;
+ p->excitation[i] = scaling * r;
+ }
+ ff_celp_lp_synthesis_filterf(p->filter_out + p->order, p->lpc_coef,
+ p->excitation, avctx->frame_size, p->order);
+
+ p->avframe.nb_samples = avctx->frame_size;
+ if ((ret = avctx->get_buffer(avctx, &p->avframe)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return ret;
+ }
+ buf_out = (int16_t *)p->avframe.data[0];
+ for (i = 0; i < avctx->frame_size; i++)
+ buf_out[i] = p->filter_out[i + p->order];
+ memcpy(p->filter_out, p->filter_out + avctx->frame_size,
+ p->order * sizeof(*p->filter_out));
+
+ *got_frame_ptr = 1;
+ *(AVFrame *)data = p->avframe;
+
+ return buf_size;
+}
+
+AVCodec ff_comfortnoise_decoder = {
+ .name = "comfortnoise",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_COMFORT_NOISE,
+ .priv_data_size = sizeof(CNGContext),
+ .init = cng_decode_init,
+ .decode = cng_decode_frame,
+ .close = cng_decode_close,
+ .long_name = NULL_IF_CONFIG_SMALL("RFC 3389 comfort noise generator"),
+ .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
+ AV_SAMPLE_FMT_NONE },
+ .capabilities = CODEC_CAP_DELAY | CODEC_CAP_DR1,
+};
diff --git a/libavcodec/cngenc.c b/libavcodec/cngenc.c
new file mode 100644
index 0000000..1e3f8f0
--- /dev/null
+++ b/libavcodec/cngenc.c
@@ -0,0 +1,116 @@
+/*
+ * RFC 3389 comfort noise generator
+ * Copyright (c) 2012 Martin Storsjo
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <math.h>
+
+#include "libavutil/common.h"
+#include "avcodec.h"
+#include "internal.h"
+#include "lpc.h"
+
+typedef struct CNGContext {
+ LPCContext lpc;
+ int order;
+ int32_t *samples32;
+ double *ref_coef;
+} CNGContext;
+
+static av_cold int cng_encode_close(AVCodecContext *avctx)
+{
+ CNGContext *p = avctx->priv_data;
+ ff_lpc_end(&p->lpc);
+ av_free(p->samples32);
+ av_free(p->ref_coef);
+ return 0;
+}
+
+static av_cold int cng_encode_init(AVCodecContext *avctx)
+{
+ CNGContext *p = avctx->priv_data;
+ int ret;
+
+ if (avctx->channels != 1) {
+ av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
+ return AVERROR(EINVAL);
+ }
+
+ avctx->frame_size = 640;
+ p->order = 10;
+ if ((ret = ff_lpc_init(&p->lpc, avctx->frame_size, p->order, FF_LPC_TYPE_LEVINSON)) < 0)
+ return ret;
+ p->samples32 = av_malloc(avctx->frame_size * sizeof(*p->samples32));
+ p->ref_coef = av_malloc(p->order * sizeof(*p->ref_coef));
+ if (!p->samples32 || !p->ref_coef) {
+ cng_encode_close(avctx);
+ return AVERROR(ENOMEM);
+ }
+
+ return 0;
+}
+
+static int cng_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
+ const AVFrame *frame, int *got_packet_ptr)
+{
+ CNGContext *p = avctx->priv_data;
+ int ret, i;
+ double energy = 0;
+ int qdbov;
+ int16_t *samples = (int16_t*) frame->data[0];
+
+ if ((ret = ff_alloc_packet(avpkt, 1 + p->order))) {
+ av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
+ return ret;
+ }
+
+ for (i = 0; i < frame->nb_samples; i++) {
+ p->samples32[i] = samples[i];
+ energy += samples[i] * samples[i];
+ }
+ energy /= frame->nb_samples;
+ if (energy > 0) {
+ double dbov = 10 * log10(energy / 1081109975);
+ qdbov = av_clip(-floor(dbov), 0, 127);
+ } else {
+ qdbov = 127;
+ }
+ ret = ff_lpc_calc_ref_coefs(&p->lpc, p->samples32, p->order, p->ref_coef);
+ avpkt->data[0] = qdbov;
+ for (i = 0; i < p->order; i++)
+ avpkt->data[1 + i] = p->ref_coef[i] * 127 + 127;
+
+ *got_packet_ptr = 1;
+ avpkt->size = 1 + p->order;
+
+ return 0;
+}
+
+AVCodec ff_comfortnoise_encoder = {
+ .name = "comfortnoise",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = AV_CODEC_ID_COMFORT_NOISE,
+ .priv_data_size = sizeof(CNGContext),
+ .init = cng_encode_init,
+ .encode2 = cng_encode_frame,
+ .close = cng_encode_close,
+ .long_name = NULL_IF_CONFIG_SMALL("RFC 3389 comfort noise generator"),
+ .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
+ AV_SAMPLE_FMT_NONE },
+};
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 818a35e..a8ff314 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -2112,6 +2112,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
.long_name = NULL_IF_CONFIG_SMALL("Opus (Opus Interactive Audio Codec)"),
.props = AV_CODEC_PROP_LOSSY,
},
+ {
+ .id = AV_CODEC_ID_COMFORT_NOISE,
+ .type = AVMEDIA_TYPE_AUDIO,
+ .name = "comfortnoise",
+ .long_name = NULL_IF_CONFIG_SMALL("RFC 3389 Comfort Noise"),
+ .props = AV_CODEC_PROP_LOSSY,
+ },
/* subtitle codecs */
{
diff --git a/libavcodec/version.h b/libavcodec/version.h
index b702f4b..5ee7c7c 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -27,7 +27,7 @@
*/
#define LIBAVCODEC_VERSION_MAJOR 54
-#define LIBAVCODEC_VERSION_MINOR 31
+#define LIBAVCODEC_VERSION_MINOR 32
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
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