From 067cbf313f8031782e1a40c2a97fbeef8dc2416d Mon Sep 17 00:00:00 2001 From: Zdenek Kabelac Date: Fri, 6 Jun 2003 11:47:49 +0000 Subject: * amr format - by Johannes Carlsson Originally committed as revision 1934 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/amr.c | 178 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 178 insertions(+) create mode 100644 libavformat/amr.c (limited to 'libavformat') diff --git a/libavformat/amr.c b/libavformat/amr.c new file mode 100644 index 0000000000..720bf31f55 --- /dev/null +++ b/libavformat/amr.c @@ -0,0 +1,178 @@ +/* + * amr file format + * Copyright (c) 2001 ffmpeg project + * + * This library 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 of the License, or (at your option) any later version. + * + * This library 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 this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* +Write and read amr data according to RFC3267, http://www.ietf.org/rfc/rfc3267.txt?number=3267 + +Only amr narrowband (not amr-wb) is supported for now. + +*/ +#include "avformat.h" +#include "avi.h" + +static const unsigned char AMR_header [] = "#!AMR\n"; + +/* AMR_FILE header */ +static int put_amr_header(ByteIOContext *pb, AVCodecContext *enc) +{ + put_tag(pb, AMR_header); /* magic number */ + return 0; +} + +static int amr_write_header(AVFormatContext *s) +{ + ByteIOContext *pb = &s->pb; + + s->priv_data = NULL; + + /* format header */ + if (put_amr_header(pb, &s->streams[0]->codec) < 0) { + return -1; + } + + put_flush_packet(pb); + + return 0; +} + +static int amr_write_packet(AVFormatContext *s, int stream_index_ptr, + uint8_t *buf, int size, int force_pts) +{ + put_buffer(&s->pb, buf, size); + put_flush_packet(&s->pb); + return 0; +} + +static int amr_write_trailer(AVFormatContext *s) +{ + return 0; +} + +static int amr_probe(AVProbeData *p) +{ + /* check file header */ + if (p->buf_size < 6) + return 0; + if(memcmp(p->buf,AMR_header,6)==0) + return AVPROBE_SCORE_MAX; + else + return 0; +} + +/* amr input */ +static int amr_read_header(AVFormatContext *s, + AVFormatParameters *ap) +{ + ByteIOContext *pb = &s->pb; + AVStream *st; + u_int8_t header[6]; + + get_buffer(pb, header, 6); + + if(memcmp(header,AMR_header,6)!=0) + { + return -1; + } + + st = av_new_stream(s, 0); + if (!st) + return AVERROR_NOMEM; + + st->codec.codec_type = CODEC_TYPE_AUDIO; + st->codec.codec_tag = CODEC_ID_AMR_NB; + st->codec.codec_id = CODEC_ID_AMR_NB; + st->codec.channels = 1; + st->codec.sample_rate = 8000; + return 0; +} + +#define MAX_SIZE 32 + +static int amr_read_packet(AVFormatContext *s, + AVPacket *pkt) +{ + static u_int16_t packed_size[16] = {12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0}; + u_int8_t toc, q, ft; + int read; + int size; + + if (url_feof(&s->pb)) + return -EIO; + + toc=0; + + toc=get_byte(&s->pb); + + q = (toc >> 2) & 0x01; + ft = (toc >> 3) & 0x0F; + + size=packed_size[ft]; + //printf("amr_read_packet size=%d\n",size); + + if (av_new_packet(pkt, size+1)) + return -EIO; + pkt->stream_index = 0; + + pkt->data[0]=toc; + + read = get_buffer(&s->pb, pkt->data+1, size); + + if (read != size) + { + av_free_packet(pkt); + return -EIO; + } + + return 0; +} + +static int amr_read_close(AVFormatContext *s) +{ + return 0; +} + +static AVInputFormat amr_iformat = { + "amr", + "3gpp amr file format", + 0, + amr_probe, + amr_read_header, + amr_read_packet, + amr_read_close, +}; + +static AVOutputFormat amr_oformat = { + "amr", + "3gpp amr file format", + "audio/amr", + "amr", + 0, + CODEC_ID_AMR_NB, + CODEC_ID_NONE, + amr_write_header, + amr_write_packet, + amr_write_trailer, +}; + +int amr_init(void) +{ + av_register_input_format(&amr_iformat); + av_register_output_format(&amr_oformat); + return 0; +} -- cgit v1.2.3