| /* |
| * Opus decoder using libopus |
| * Copyright (c) 2012 Nicolas George |
| * |
| * 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 <opus.h> |
| #include <opus_multistream.h> |
| #include "avcodec.h" |
| #include "internal.h" |
| #include "vorbis.h" |
| #include "libavutil/avassert.h" |
| #include "libavutil/intreadwrite.h" |
| |
| struct libopus_context { |
| OpusMSDecoder *dec; |
| AVFrame frame; |
| int pre_skip; |
| #ifndef OPUS_SET_GAIN |
| union { int i; double d; } gain; |
| #endif |
| }; |
| |
| static int ff_opus_error_to_averror(int err) |
| { |
| switch (err) { |
| case OPUS_BAD_ARG: return AVERROR(EINVAL); |
| case OPUS_BUFFER_TOO_SMALL: return AVERROR_BUFFER_TOO_SMALL; |
| case OPUS_INTERNAL_ERROR: return AVERROR(EFAULT); |
| case OPUS_INVALID_PACKET: return AVERROR_INVALIDDATA; |
| case OPUS_UNIMPLEMENTED: return AVERROR(ENOSYS); |
| case OPUS_INVALID_STATE: return AVERROR_EXTERNAL; |
| case OPUS_ALLOC_FAIL: return AVERROR(ENOMEM); |
| default: return AVERROR(EINVAL); |
| } |
| } |
| |
| static inline void reorder(uint8_t *data, unsigned channels, unsigned bps, |
| unsigned samples, const uint8_t *map) |
| { |
| uint8_t tmp[8 * 4]; |
| unsigned i; |
| |
| av_assert1(channels * bps <= sizeof(tmp)); |
| for (; samples > 0; samples--) { |
| for (i = 0; i < channels; i++) |
| memcpy(tmp + bps * i, data + bps * map[i], bps); |
| memcpy(data, tmp, bps * channels); |
| data += bps * channels; |
| } |
| } |
| |
| #define OPUS_HEAD_SIZE 19 |
| |
| static av_cold int libopus_dec_init(AVCodecContext *avc) |
| { |
| struct libopus_context *opus = avc->priv_data; |
| int ret, channel_map = 0, gain_db = 0, nb_streams, nb_coupled; |
| uint8_t mapping_stereo[] = { 0, 1 }, *mapping; |
| |
| avc->sample_rate = 48000; |
| avc->sample_fmt = avc->request_sample_fmt == AV_SAMPLE_FMT_FLT ? |
| AV_SAMPLE_FMT_FLT : AV_SAMPLE_FMT_S16; |
| avc->channel_layout = avc->channels > 8 ? 0 : |
| ff_vorbis_channel_layouts[avc->channels - 1]; |
| |
| if (avc->extradata_size >= OPUS_HEAD_SIZE) { |
| opus->pre_skip = AV_RL16(avc->extradata + 10); |
| gain_db = AV_RL16(avc->extradata + 16); |
| channel_map = AV_RL8 (avc->extradata + 18); |
| gain_db -= (gain_db & 0x8000) << 1; /* signed */ |
| } |
| if (avc->extradata_size >= OPUS_HEAD_SIZE + 2 + avc->channels) { |
| nb_streams = avc->extradata[OPUS_HEAD_SIZE + 0]; |
| nb_coupled = avc->extradata[OPUS_HEAD_SIZE + 1]; |
| if (nb_streams + nb_coupled != avc->channels) |
| av_log(avc, AV_LOG_WARNING, "Inconsistent channel mapping.\n"); |
| mapping = avc->extradata + OPUS_HEAD_SIZE + 2; |
| } else { |
| if (avc->channels > 2 || channel_map) { |
| av_log(avc, AV_LOG_ERROR, |
| "No channel mapping for %d channels.\n", avc->channels); |
| return AVERROR(EINVAL); |
| } |
| nb_streams = 1; |
| nb_coupled = avc->channels > 1; |
| mapping = mapping_stereo; |
| } |
| |
| opus->dec = opus_multistream_decoder_create( |
| avc->sample_rate, avc->channels, |
| nb_streams, nb_coupled, mapping, &ret); |
| if (!opus->dec) { |
| av_log(avc, AV_LOG_ERROR, "Unable to create decoder: %s\n", |
| opus_strerror(ret)); |
| return ff_opus_error_to_averror(ret); |
| } |
| |
| #ifdef OPUS_SET_GAIN |
| ret = opus_multistream_decoder_ctl(opus->dec, OPUS_SET_GAIN(gain_db)); |
| if (ret != OPUS_OK) |
| av_log(avc, AV_LOG_WARNING, "Failed to set gain: %s\n", |
| opus_strerror(ret)); |
| #else |
| { |
| double gain_lin = pow(10, gain_db / (20.0 * 256)); |
| if (avc->sample_fmt == AV_SAMPLE_FMT_FLT) |
| opus->gain.d = gain_lin; |
| else |
| opus->gain.i = FFMIN(gain_lin * 65536, INT_MAX); |
| } |
| #endif |
| |
| avc->internal->skip_samples = opus->pre_skip; |
| avcodec_get_frame_defaults(&opus->frame); |
| avc->coded_frame = &opus->frame; |
| return 0; |
| } |
| |
| static av_cold int libopus_dec_close(AVCodecContext *avc) |
| { |
| struct libopus_context *opus = avc->priv_data; |
| |
| opus_multistream_decoder_destroy(opus->dec); |
| return 0; |
| } |
| |
| #define MAX_FRAME_SIZE (960*6) |
| |
| static int libopus_dec_decode(AVCodecContext *avc, void *frame, |
| int *got_frame_ptr, AVPacket *pkt) |
| { |
| struct libopus_context *opus = avc->priv_data; |
| int ret, nb_samples; |
| |
| opus->frame.nb_samples = MAX_FRAME_SIZE; |
| ret = avc->get_buffer(avc, &opus->frame); |
| if (ret < 0) { |
| av_log(avc, AV_LOG_ERROR, "get_buffer() failed\n"); |
| return ret; |
| } |
| |
| nb_samples = avc->sample_fmt == AV_SAMPLE_FMT_S16 ? |
| opus_multistream_decode (opus->dec, pkt->data, pkt->size, |
| (void *)opus->frame.data[0], |
| opus->frame.nb_samples, 0) : |
| opus_multistream_decode_float(opus->dec, pkt->data, pkt->size, |
| (void *)opus->frame.data[0], |
| opus->frame.nb_samples, 0); |
| if (nb_samples < 0) { |
| av_log(avc, AV_LOG_ERROR, "Decoding error: %s\n", |
| opus_strerror(nb_samples)); |
| return ff_opus_error_to_averror(nb_samples); |
| } |
| |
| if (avc->channels > 3 && avc->channels <= 8) { |
| const uint8_t *m = ff_vorbis_channel_layout_offsets[avc->channels - 1]; |
| if (avc->sample_fmt == AV_SAMPLE_FMT_S16) |
| reorder(opus->frame.data[0], avc->channels, 2, nb_samples, m); |
| else |
| reorder(opus->frame.data[0], avc->channels, 4, nb_samples, m); |
| } |
| |
| #ifndef OPUS_SET_GAIN |
| { |
| int i = avc->channels * nb_samples; |
| if (avc->sample_fmt == AV_SAMPLE_FMT_FLT) { |
| float *pcm = (float *)opus->frame.data[0]; |
| for (; i > 0; i--, pcm++) |
| *pcm = av_clipf(*pcm * opus->gain.d, -1, 1); |
| } else { |
| int16_t *pcm = (int16_t *)opus->frame.data[0]; |
| for (; i > 0; i--, pcm++) |
| *pcm = av_clip_int16(((int64_t)opus->gain.i * *pcm) >> 16); |
| } |
| } |
| #endif |
| |
| opus->frame.nb_samples = nb_samples; |
| *(AVFrame *)frame = opus->frame; |
| *got_frame_ptr = 1; |
| return pkt->size; |
| } |
| |
| static void libopus_dec_flush(AVCodecContext *avc) |
| { |
| struct libopus_context *opus = avc->priv_data; |
| |
| opus_multistream_decoder_ctl(opus->dec, OPUS_RESET_STATE); |
| /* The stream can have been extracted by a tool that is not Opus-aware. |
| Therefore, any packet can become the first of the stream. */ |
| avc->internal->skip_samples = opus->pre_skip; |
| } |
| |
| AVCodec ff_libopus_decoder = { |
| .name = "libopus", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = AV_CODEC_ID_OPUS, |
| .priv_data_size = sizeof(struct libopus_context), |
| .init = libopus_dec_init, |
| .close = libopus_dec_close, |
| .decode = libopus_dec_decode, |
| .flush = libopus_dec_flush, |
| .capabilities = CODEC_CAP_DR1, |
| .long_name = NULL_IF_CONFIG_SMALL("libopus Opus"), |
| }; |
