libavcodec/libcodec2.c

   1 /*
   2  * codec2 encoder/decoder using libcodec2
   3  * Copyright (c) 2017 Tomas Härdin
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <codec2/codec2.h>
  23 #include "libavutil/channel_layout.h"
  24 #include "libavutil/mem.h"
  25 #include "avcodec.h"
  26 #include "libavutil/opt.h"
  27 #include "codec_internal.h"
  28 #include "decode.h"
  29 #include "encode.h"
  30 #include "codec2utils.h"
  31
  32 typedef struct {
  33     const AVClass *class;
  34     struct CODEC2 *codec;
  35     int mode;
  36 } LibCodec2Context;
  37
  38 static const AVOption options[] = {
  39     //not AV_OPT_FLAG_DECODING_PARAM since mode should come from the demuxer
  40     //1300 (aka FreeDV 1600) is the most common mode on-the-air, default to it here as well
  41     CODEC2_AVOPTIONS("codec2 mode", LibCodec2Context, 0, 4 /*CODEC2_MODE_1300*/, AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_ENCODING_PARAM),
  42     { NULL },
  43 };
  44
  45 static const AVClass libcodec2_enc_class = {
  46     .class_name = "libcodec2 encoder",
  47     .item_name  = av_default_item_name,
  48     .option     = options,
  49     .version    = LIBAVUTIL_VERSION_INT,
  50 };
  51
  52 static av_cold int libcodec2_init_common(AVCodecContext *avctx, int mode)
  53 {
  54     LibCodec2Context *c2 = avctx->priv_data;
  55     //Grab mode name from options, unless it's some weird number.
  56     const char *modename = mode >= 0 && mode <= CODEC2_MODE_MAX ? options[mode+1].name : "?";
  57
  58     c2->codec = codec2_create(mode);
  59     if (!c2->codec) {
  60         //Out of memory or unsupported mode. The latter seems most likely,
  61         //but we can't tell for sure with the current API.
  62         goto libcodec2_init_common_error;
  63     }
  64
  65     avctx->frame_size = codec2_samples_per_frame(c2->codec);
  66     avctx->block_align = (codec2_bits_per_frame(c2->codec) + 7) / 8;
  67
  68     if (avctx->frame_size <= 0 || avctx->block_align <= 0) {
  69         //codec2_create() may succeed for some modes but still fail at codec2_samples_per_frame()
  70         //example is -mode 700C on libcodec2 0.4
  71         codec2_destroy(c2->codec);
  72         c2->codec = NULL;
  73         goto libcodec2_init_common_error;
  74     }
  75
  76     codec2_set_natural_or_gray(c2->codec, 1);
  77
  78     return 0;
  79
  80 libcodec2_init_common_error:
  81     av_log(avctx, AV_LOG_ERROR,
  82         "Mode %i (%s) not supported with the linked version of libcodec2\n",
  83         mode, modename);
  84     return AVERROR(EINVAL);
  85 }
  86
  87 static av_cold int libcodec2_init_decoder(AVCodecContext *avctx)
  88 {
  89     avctx->sample_rate      = 8000;
  90     avctx->sample_fmt       = AV_SAMPLE_FMT_S16;
  91     av_channel_layout_uninit(&avctx->ch_layout);
  92     avctx->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
  93
  94     if (avctx->extradata_size != CODEC2_EXTRADATA_SIZE) {
  95         av_log(avctx, AV_LOG_ERROR, "must have exactly %i bytes of extradata (got %i)\n",
  96                CODEC2_EXTRADATA_SIZE, avctx->extradata_size);
  97         return AVERROR_INVALIDDATA;
  98     }
  99
 100     return libcodec2_init_common(avctx, codec2_mode_from_extradata(avctx->extradata));
 101 }
 102
 103 static av_cold int libcodec2_init_encoder(AVCodecContext *avctx)
 104 {
 105     LibCodec2Context *c2 = avctx->priv_data;
 106
 107     //will need to be smarter once we get wideband support
 108     if (avctx->sample_rate != 8000 ||
 109         avctx->sample_fmt != AV_SAMPLE_FMT_S16) {
 110         av_log(avctx, AV_LOG_ERROR, "only 8 kHz 16-bit mono allowed\n");
 111         return AVERROR(EINVAL);
 112     }
 113
 114     avctx->extradata = av_mallocz(CODEC2_EXTRADATA_SIZE + AV_INPUT_BUFFER_PADDING_SIZE);
 115     if (!avctx->extradata) {
 116         return AVERROR(ENOMEM);
 117     }
 118
 119     avctx->extradata_size = CODEC2_EXTRADATA_SIZE;
 120     codec2_make_extradata(avctx->extradata, c2->mode);
 121
 122     return libcodec2_init_common(avctx, c2->mode);
 123 }
 124
 125 static av_cold int libcodec2_close(AVCodecContext *avctx)
 126 {
 127     LibCodec2Context *c2 = avctx->priv_data;
 128
 129     codec2_destroy(c2->codec);
 130     return 0;
 131 }
 132
 133 static int libcodec2_decode(AVCodecContext *avctx, AVFrame *frame,
 134                             int *got_frame_ptr, AVPacket *pkt)
 135 {
 136     LibCodec2Context *c2 = avctx->priv_data;
 137     int ret, nframes, i;
 138     const uint8_t *input;
 139     int16_t *output;
 140
 141     nframes           = pkt->size / avctx->block_align;
 142     frame->nb_samples = avctx->frame_size * nframes;
 143
 144     ret = ff_get_buffer(avctx, frame, 0);
 145     if (ret < 0) {
 146         return ret;
 147     }
 148
 149     input  = pkt->data;
 150     output = (int16_t *)frame->data[0];
 151
 152     for (i = 0; i < nframes; i++) {
 153         codec2_decode(c2->codec, output, input);
 154         input  += avctx->block_align;
 155         output += avctx->frame_size;
 156     }
 157
 158     *got_frame_ptr = nframes > 0;
 159     return nframes * avctx->block_align;
 160 }
 161
 162 static int libcodec2_encode(AVCodecContext *avctx, AVPacket *avpkt,
 163                             const AVFrame *frame, int *got_packet_ptr)
 164 {
 165     LibCodec2Context *c2 = avctx->priv_data;
 166     int16_t *samples = (int16_t *)frame->data[0];
 167
 168     int ret = ff_get_encode_buffer(avctx, avpkt, avctx->block_align, 0);
 169     if (ret < 0) {
 170         return ret;
 171     }
 172
 173     codec2_encode(c2->codec, avpkt->data, samples);
 174     *got_packet_ptr = 1;
 175
 176     return 0;
 177 }
 178
 179 const FFCodec ff_libcodec2_decoder = {
 180     .p.name                 = "libcodec2",
 181     CODEC_LONG_NAME("codec2 decoder using libcodec2"),
 182     .p.type                 = AVMEDIA_TYPE_AUDIO,
 183     .p.id                   = AV_CODEC_ID_CODEC2,
 184     .p.capabilities         = AV_CODEC_CAP_CHANNEL_CONF,
 185     CODEC_SAMPLERATES(8000),
 186     CODEC_SAMPLEFMTS(AV_SAMPLE_FMT_S16),
 187     CODEC_CH_LAYOUTS(AV_CHANNEL_LAYOUT_MONO),
 188     .caps_internal          = FF_CODEC_CAP_NOT_INIT_THREADSAFE,
 189     .priv_data_size         = sizeof(LibCodec2Context),
 190     .init                   = libcodec2_init_decoder,
 191     .close                  = libcodec2_close,
 192     FF_CODEC_DECODE_CB(libcodec2_decode),
 193 };
 194
 195 const FFCodec ff_libcodec2_encoder = {
 196     .p.name                 = "libcodec2",
 197     CODEC_LONG_NAME("codec2 encoder using libcodec2"),
 198     .p.type                 = AVMEDIA_TYPE_AUDIO,
 199     .p.id                   = AV_CODEC_ID_CODEC2,
 200     .p.capabilities         = AV_CODEC_CAP_DR1 |
 201                               AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
 202     CODEC_SAMPLERATES(8000),
 203     CODEC_SAMPLEFMTS(AV_SAMPLE_FMT_S16),
 204     CODEC_CH_LAYOUTS(AV_CHANNEL_LAYOUT_MONO),
 205     .p.priv_class           = &libcodec2_enc_class,
 206     .caps_internal          = FF_CODEC_CAP_NOT_INIT_THREADSAFE,
 207     .priv_data_size         = sizeof(LibCodec2Context),
 208     .init                   = libcodec2_init_encoder,
 209     .close                  = libcodec2_close,
 210     FF_CODEC_ENCODE_CB(libcodec2_encode),
 211 };