yading@11: /*
yading@11:  * RTP packetization for AMR audio
yading@11:  * Copyright (c) 2007 Luca Abeni
yading@11:  * Copyright (c) 2009 Martin Storsjo
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "avformat.h"
yading@11: #include "rtpenc.h"
yading@11: 
yading@11: /**
yading@11:  * Packetize AMR frames into RTP packets according to RFC 3267,
yading@11:  * in octet-aligned mode.
yading@11:  */
yading@11: void ff_rtp_send_amr(AVFormatContext *s1, const uint8_t *buff, int size)
yading@11: {
yading@11:     RTPMuxContext *s          = s1->priv_data;
yading@11:     int max_header_toc_size   = 1 + s->max_frames_per_packet;
yading@11:     uint8_t *p;
yading@11:     int len;
yading@11: 
yading@11:     /* Test if the packet must be sent. */
yading@11:     len = s->buf_ptr - s->buf;
yading@11:     if (s->num_frames == s->max_frames_per_packet || (len && len + size - 1 > s->max_payload_size)) {
yading@11:         int header_size = s->num_frames + 1;
yading@11:         p = s->buf + max_header_toc_size - header_size;
yading@11:         if (p != s->buf)
yading@11:             memmove(p, s->buf, header_size);
yading@11: 
yading@11:         ff_rtp_send_data(s1, p, s->buf_ptr - p, 1);
yading@11: 
yading@11:         s->num_frames = 0;
yading@11:     }
yading@11: 
yading@11:     if (!s->num_frames) {
yading@11:         s->buf[0]    = 0xf0;
yading@11:         s->buf_ptr   = s->buf + max_header_toc_size;
yading@11:         s->timestamp = s->cur_timestamp;
yading@11:     } else {
yading@11:         /* Mark the previous TOC entry as having more entries following. */
yading@11:         s->buf[1 + s->num_frames - 1] |= 0x80;
yading@11:     }
yading@11: 
yading@11:     /* Copy the frame type and quality bits. */
yading@11:     s->buf[1 + s->num_frames++] = buff[0] & 0x7C;
yading@11:     buff++;
yading@11:     size--;
yading@11:     memcpy(s->buf_ptr, buff, size);
yading@11:     s->buf_ptr += size;
yading@11: }