diff options
Diffstat (limited to 'libavformat/g726.c')
-rw-r--r-- | libavformat/g726.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/libavformat/g726.c b/libavformat/g726.c new file mode 100644 index 0000000000..eca9404866 --- /dev/null +++ b/libavformat/g726.c @@ -0,0 +1,105 @@ +/* + * G.726 raw demuxer + * Copyright 2017 Carl Eugen Hoyos + * + * 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 "avformat.h" +#include "internal.h" +#include "libavutil/opt.h" + +typedef struct G726Context { + AVClass *class; + int code_size; + int sample_rate; +} G726Context; + +static int g726_read_header(AVFormatContext *s) +{ + G726Context *c = s->priv_data; + AVStream *st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + + st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; + st->codecpar->codec_id = s->iformat->raw_codec_id; + + st->codecpar->sample_rate = c->sample_rate; + st->codecpar->bits_per_coded_sample = c->code_size; + st->codecpar->bit_rate = ((int[]){ 16000, 24000, 32000, 40000 })[c->code_size - 2]; + st->codecpar->channels = 1; + + return 0; +} + +static int g726_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + int res; + res = av_get_packet(s->pb, pkt, 1020); // a size similar to RAW_PACKET_SIZE divisible by all code_size values + if (res < 0) + return res; + return 0; +} + +#define OFFSET(x) offsetof(G726Context, x) +static const AVOption options[] = { + { "code_size", "Bits per G.726 code", + OFFSET(code_size), AV_OPT_TYPE_INT, {.i64 = 4}, 2, 5, AV_OPT_FLAG_DECODING_PARAM }, + { "sample_rate", "", + OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 8000}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM }, + { NULL }, +}; + +#if CONFIG_G726_DEMUXER +static const AVClass g726le_demuxer_class = { + .class_name = "G.726 big-endian demuxer", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_g726_demuxer = { + .name = "g726", + .long_name = NULL_IF_CONFIG_SMALL("raw big-endian G.726 (\"left aligned\")"), + .read_header = g726_read_header, + .read_packet = g726_read_packet, + .priv_data_size = sizeof(G726Context), + .priv_class = &g726le_demuxer_class, + .raw_codec_id = AV_CODEC_ID_ADPCM_G726, +}; +#endif + +#if CONFIG_G726LE_DEMUXER +static const AVClass g726_demuxer_class = { + .class_name = "G.726 little-endian demuxer", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_g726le_demuxer = { + .name = "g726le", + .long_name = NULL_IF_CONFIG_SMALL("raw little-endian G.726 (\"right aligned\")"), + .read_header = g726_read_header, + .read_packet = g726_read_packet, + .priv_data_size = sizeof(G726Context), + .priv_class = &g726_demuxer_class, + .raw_codec_id = AV_CODEC_ID_ADPCM_G726LE, +}; +#endif + |