| /* |
| * AMR Audio encoder stub |
| * Copyright (c) 2003 the ffmpeg project |
| * |
| * 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 <vo-amrwbenc/enc_if.h> |
| |
| #include "avcodec.h" |
| #include "libavutil/avstring.h" |
| #include "libavutil/opt.h" |
| |
| typedef struct AMRWBContext { |
| AVClass *av_class; |
| void *state; |
| int mode; |
| int last_bitrate; |
| int allow_dtx; |
| } AMRWBContext; |
| |
| static const AVOption options[] = { |
| { "dtx", "Allow DTX (generate comfort noise)", offsetof(AMRWBContext, allow_dtx), AV_OPT_TYPE_INT, { 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM }, |
| { NULL } |
| }; |
| |
| static const AVClass class = { |
| "libvo_amrwbenc", av_default_item_name, options, LIBAVUTIL_VERSION_INT |
| }; |
| |
| static int get_wb_bitrate_mode(int bitrate, void *log_ctx) |
| { |
| /* make the correspondance between bitrate and mode */ |
| static const int rates[] = { 6600, 8850, 12650, 14250, 15850, 18250, |
| 19850, 23050, 23850 }; |
| int i, best = -1, min_diff = 0; |
| char log_buf[200]; |
| |
| for (i = 0; i < 9; i++) { |
| if (rates[i] == bitrate) |
| return i; |
| if (best < 0 || abs(rates[i] - bitrate) < min_diff) { |
| best = i; |
| min_diff = abs(rates[i] - bitrate); |
| } |
| } |
| /* no bitrate matching exactly, log a warning */ |
| snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of "); |
| for (i = 0; i < 9; i++) |
| av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i] / 1000.f); |
| av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best] / 1000.f); |
| av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf); |
| |
| return best; |
| } |
| |
| static av_cold int amr_wb_encode_init(AVCodecContext *avctx) |
| { |
| AMRWBContext *s = avctx->priv_data; |
| |
| if (avctx->sample_rate != 16000) { |
| av_log(avctx, AV_LOG_ERROR, "Only 16000Hz sample rate supported\n"); |
| return AVERROR(ENOSYS); |
| } |
| |
| if (avctx->channels != 1) { |
| av_log(avctx, AV_LOG_ERROR, "Only mono supported\n"); |
| return AVERROR(ENOSYS); |
| } |
| |
| s->mode = get_wb_bitrate_mode(avctx->bit_rate, avctx); |
| s->last_bitrate = avctx->bit_rate; |
| |
| avctx->frame_size = 320; |
| avctx->coded_frame = avcodec_alloc_frame(); |
| |
| s->state = E_IF_init(); |
| |
| return 0; |
| } |
| |
| static int amr_wb_encode_close(AVCodecContext *avctx) |
| { |
| AMRWBContext *s = avctx->priv_data; |
| |
| E_IF_exit(s->state); |
| av_freep(&avctx->coded_frame); |
| return 0; |
| } |
| |
| static int amr_wb_encode_frame(AVCodecContext *avctx, |
| unsigned char *frame/*out*/, |
| int buf_size, void *data/*in*/) |
| { |
| AMRWBContext *s = avctx->priv_data; |
| int size; |
| |
| if (s->last_bitrate != avctx->bit_rate) { |
| s->mode = get_wb_bitrate_mode(avctx->bit_rate, avctx); |
| s->last_bitrate = avctx->bit_rate; |
| } |
| size = E_IF_encode(s->state, s->mode, data, frame, s->allow_dtx); |
| return size; |
| } |
| |
| AVCodec ff_libvo_amrwbenc_encoder = { |
| .name = "libvo_amrwbenc", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = CODEC_ID_AMR_WB, |
| .priv_data_size = sizeof(AMRWBContext), |
| .init = amr_wb_encode_init, |
| .encode = amr_wb_encode_frame, |
| .close = amr_wb_encode_close, |
| .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE}, |
| .long_name = NULL_IF_CONFIG_SMALL("Android VisualOn Adaptive Multi-Rate " |
| "(AMR) Wide-Band"), |
| .priv_class = &class, |
| }; |
| |