00001 /* 00002 * RTP packetization for AMR audio 00003 * Copyright (c) 2007 Luca Abeni 00004 * Copyright (c) 2009 Martin Storsjo 00005 * 00006 * This file is part of FFmpeg. 00007 * 00008 * FFmpeg is free software; you can redistribute it and/or 00009 * modify it under the terms of the GNU Lesser General Public 00010 * License as published by the Free Software Foundation; either 00011 * version 2.1 of the License, or (at your option) any later version. 00012 * 00013 * FFmpeg is distributed in the hope that it will be useful, 00014 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00016 * Lesser General Public License for more details. 00017 * 00018 * You should have received a copy of the GNU Lesser General Public 00019 * License along with FFmpeg; if not, write to the Free Software 00020 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00021 */ 00022 00023 #include "avformat.h" 00024 #include "rtpenc.h" 00025 00030 void ff_rtp_send_amr(AVFormatContext *s1, const uint8_t *buff, int size) 00031 { 00032 RTPMuxContext *s = s1->priv_data; 00033 int max_header_toc_size = 1 + s->max_frames_per_packet; 00034 uint8_t *p; 00035 int len; 00036 00037 /* Test if the packet must be sent. */ 00038 len = s->buf_ptr - s->buf; 00039 if (s->num_frames == s->max_frames_per_packet || (len && len + size - 1 > s->max_payload_size)) { 00040 int header_size = s->num_frames + 1; 00041 p = s->buf + max_header_toc_size - header_size; 00042 if (p != s->buf) 00043 memmove(p, s->buf, header_size); 00044 00045 ff_rtp_send_data(s1, p, s->buf_ptr - p, 1); 00046 00047 s->num_frames = 0; 00048 } 00049 00050 if (!s->num_frames) { 00051 s->buf[0] = 0xf0; 00052 s->buf_ptr = s->buf + max_header_toc_size; 00053 s->timestamp = s->cur_timestamp; 00054 } else { 00055 /* Mark the previous TOC entry as having more entries following. */ 00056 s->buf[1 + s->num_frames - 1] |= 0x80; 00057 } 00058 00059 /* Copy the frame type and quality bits. */ 00060 s->buf[1 + s->num_frames++] = buff[0] & 0x7C; 00061 buff++; 00062 size--; 00063 memcpy(s->buf_ptr, buff, size); 00064 s->buf_ptr += size; 00065 } 00066