Add libcodec2 en/decoder

1 files changed, 213 insertions, 0 deletions

diff --git a/libavcodec/libcodec2.c b/libavcodec/libcodec2.c
new file mode 100644
index 0000000..1d6bed0
--- /dev/null
+++ b/libavcodec/libcodec2.c
@@ -0,0 +1,213 @@
+/*
+ * codec2 encoder/decoder using libcodec2
+ * Copyright (c) 2017 Tomas Härdin
+ *
+ * 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
+ */
+
+#include <codec2/codec2.h>
+#include "avcodec.h"
+#include "libavutil/opt.h"
+#include "internal.h"
+#include "codec2utils.h"
+
+typedef struct {
+    const AVClass *class;
+    struct CODEC2 *codec;
+    int mode;
+} LibCodec2Context;
+
+static const AVOption options[] = {
+    //not AV_OPT_FLAG_DECODING_PARAM since mode should come from the demuxer
+    //1300 (aka FreeDV 1600) is the most common mode on-the-air, default to it here as well
+    AVPRIV_CODEC2_AVOPTIONS("codec2 mode", LibCodec2Context, 0, 4 /*CODEC2_MODE_1300*/, AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_ENCODING_PARAM),
+    { NULL },
+};
+
+static const AVClass libcodec2_enc_class = {
+    .class_name = "libcodec2 encoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+static const AVClass libcodec2_dec_class = {
+    .class_name = "libcodec2 decoder",
+    .item_name  = av_default_item_name,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+static av_cold int libcodec2_init_common(AVCodecContext *avctx, int mode)
+{
+    LibCodec2Context *c2 = avctx->priv_data;
+    //Grab mode name from options, unless it's some weird number.
+    const char *modename = mode >= 0 && mode <= AVPRIV_CODEC2_MODE_MAX ? options[mode+1].name : "?";
+
+    c2->codec = codec2_create(mode);
+    if (!c2->codec) {
+        //Out of memory or unsupported mode. The latter seems most likely,
+        //but we can't tell for sure with the current API.
+        goto libcodec2_init_common_error;
+    }
+
+    avctx->frame_size = codec2_samples_per_frame(c2->codec);
+    avctx->block_align = (codec2_bits_per_frame(c2->codec) + 7) / 8;
+
+    if (avctx->frame_size <= 0 || avctx->block_align <= 0) {
+        //codec2_create() may succeed for some modes but still fail at codec2_samples_per_frame()
+        //example is -mode 700C on libcodec2 0.4
+        codec2_destroy(c2->codec);
+        c2->codec = NULL;
+        goto libcodec2_init_common_error;
+    }
+
+    codec2_set_natural_or_gray(c2->codec, 1);
+
+    return 0;
+
+libcodec2_init_common_error:
+    av_log(avctx, AV_LOG_ERROR,
+        "Mode %i (%s) not supported with the linked version of libcodec2\n",
+        mode, modename);
+    return AVERROR(EINVAL);
+}
+
+static av_cold int libcodec2_init_decoder(AVCodecContext *avctx)
+{
+    avctx->sample_rate      = 8000;
+    avctx->channels         = 1;
+    avctx->sample_fmt       = AV_SAMPLE_FMT_S16;
+    avctx->channel_layout   = AV_CH_LAYOUT_MONO;
+
+    if (avctx->extradata_size != AVPRIV_CODEC2_EXTRADATA_SIZE) {
+        av_log(avctx, AV_LOG_ERROR, "must have exactly %i bytes of extradata (got %i)\n",
+               AVPRIV_CODEC2_EXTRADATA_SIZE, avctx->extradata_size);
+        return AVERROR_INVALIDDATA;
+    }
+
+    return libcodec2_init_common(avctx, avpriv_codec2_mode_from_extradata(avctx->extradata));
+}
+
+static av_cold int libcodec2_init_encoder(AVCodecContext *avctx)
+{
+    LibCodec2Context *c2 = avctx->priv_data;
+
+    //will need to be smarter once we get wideband support
+    if (avctx->sample_rate != 8000 ||
+        avctx->channels != 1 ||
+        avctx->sample_fmt != AV_SAMPLE_FMT_S16) {
+        av_log(avctx, AV_LOG_ERROR, "only 8 kHz 16-bit mono allowed\n");
+        return AVERROR(EINVAL);
+    }
+
+    avctx->extradata = av_mallocz(AVPRIV_CODEC2_EXTRADATA_SIZE + AV_INPUT_BUFFER_PADDING_SIZE);
+    if (!avctx->extradata) {
+        return AVERROR(ENOMEM);
+    }
+
+    avctx->extradata_size = AVPRIV_CODEC2_EXTRADATA_SIZE;
+    avpriv_codec2_make_extradata(avctx->extradata, c2->mode);
+
+    return libcodec2_init_common(avctx, c2->mode);
+}
+
+static av_cold int libcodec2_close(AVCodecContext *avctx)
+{
+    LibCodec2Context *c2 = avctx->priv_data;
+
+    codec2_destroy(c2->codec);
+    return 0;
+}
+
+static int libcodec2_decode(AVCodecContext *avctx, void *data,
+                            int *got_frame_ptr, AVPacket *pkt)
+{
+    LibCodec2Context *c2 = avctx->priv_data;
+    AVFrame *frame = data;
+    int ret, nframes, i;
+    uint8_t *input;
+    int16_t *output;
+
+    nframes           = pkt->size / avctx->block_align;
+    frame->nb_samples = avctx->frame_size * nframes;
+
+    ret = ff_get_buffer(avctx, frame, 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+    input  = pkt->data;
+    output = (int16_t *)frame->data[0];
+
+    for (i = 0; i < nframes; i++) {
+        codec2_decode(c2->codec, output, input);
+        input  += avctx->block_align;
+        output += avctx->frame_size;
+    }
+
+    *got_frame_ptr = nframes > 0;
+    return nframes * avctx->block_align;
+}
+
+static int libcodec2_encode(AVCodecContext *avctx, AVPacket *avpkt,
+                            const AVFrame *frame, int *got_packet_ptr)
+{
+    LibCodec2Context *c2 = avctx->priv_data;
+    int16_t *samples = (int16_t *)frame->data[0];
+
+    int ret = ff_alloc_packet2(avctx, avpkt, avctx->block_align, 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+    codec2_encode(c2->codec, avpkt->data, samples);
+    *got_packet_ptr = 1;
+
+    return 0;
+}
+
+AVCodec ff_libcodec2_decoder = {
+    .name                   = "libcodec2",
+    .long_name              = NULL_IF_CONFIG_SMALL("codec2 decoder using libcodec2"),
+    .type                   = AVMEDIA_TYPE_AUDIO,
+    .id                     = AV_CODEC_ID_CODEC2,
+    .priv_data_size         = sizeof(LibCodec2Context),
+    .init                   = libcodec2_init_decoder,
+    .close                  = libcodec2_close,
+    .decode                 = libcodec2_decode,
+    .capabilities           = 0,
+    .supported_samplerates  = (const int[]){ 8000, 0 },
+    .sample_fmts            = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE },
+    .channel_layouts        = (const uint64_t[]) { AV_CH_LAYOUT_MONO, 0 },
+    .priv_class             = &libcodec2_dec_class,
+};
+
+AVCodec ff_libcodec2_encoder = {
+    .name                   = "libcodec2",
+    .long_name              = NULL_IF_CONFIG_SMALL("codec2 encoder using libcodec2"),
+    .type                   = AVMEDIA_TYPE_AUDIO,
+    .id                     = AV_CODEC_ID_CODEC2,
+    .priv_data_size         = sizeof(LibCodec2Context),
+    .init                   = libcodec2_init_encoder,
+    .close                  = libcodec2_close,
+    .encode2                = libcodec2_encode,
+    .capabilities           = 0,
+    .supported_samplerates  = (const int[]){ 8000, 0 },
+    .sample_fmts            = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE },
+    .channel_layouts        = (const uint64_t[]) { AV_CH_LAYOUT_MONO, 0 },
+    .priv_class             = &libcodec2_enc_class,
+};