| 1 | /* |
| 2 | * RTP VP8 Packetizer |
| 3 | * Copyright (c) 2010 Josh Allmann |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #include "rtpenc.h" |
| 23 | |
| 24 | /* Based on a draft spec for VP8 RTP. |
| 25 | * ( http://tools.ietf.org/html/draft-ietf-payload-vp8-05 ) */ |
| 26 | void ff_rtp_send_vp8(AVFormatContext *s1, const uint8_t *buf, int size) |
| 27 | { |
| 28 | RTPMuxContext *s = s1->priv_data; |
| 29 | int len, max_packet_size, header_size; |
| 30 | |
| 31 | s->buf_ptr = s->buf; |
| 32 | s->timestamp = s->cur_timestamp; |
| 33 | |
| 34 | // extended control bit set, reference frame, start of partition, |
| 35 | // partition id 0 |
| 36 | *s->buf_ptr++ = 0x90; |
| 37 | *s->buf_ptr++ = 0x80; // Picture id present |
| 38 | *s->buf_ptr++ = s->frame_count++ & 0x7f; |
| 39 | // Calculate the number of remaining bytes |
| 40 | header_size = s->buf_ptr - s->buf; |
| 41 | max_packet_size = s->max_payload_size - header_size; |
| 42 | |
| 43 | while (size > 0) { |
| 44 | len = FFMIN(size, max_packet_size); |
| 45 | |
| 46 | memcpy(s->buf_ptr, buf, len); |
| 47 | // marker bit is last packet in frame |
| 48 | ff_rtp_send_data(s1, s->buf, len + header_size, size == len); |
| 49 | |
| 50 | size -= len; |
| 51 | buf += len; |
| 52 | // Clear the partition start bit, keep the rest of the header untouched |
| 53 | s->buf[0] &= ~0x10; |
| 54 | } |
| 55 | } |