1/* 2 * RTP packetization for MPEG video 3 * Copyright (c) 2002 Fabrice Bellard 4 * Copyright (c) 2007 Luca Abeni 5 * 6 * This file is part of FFmpeg. 7 * 8 * FFmpeg is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * FFmpeg is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with FFmpeg; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23#include "libavcodec/mpegvideo.h" 24#include "avformat.h" 25#include "rtpenc.h" 26 27/* NOTE: a single frame must be passed with sequence header if 28 needed. XXX: use slices. */ 29void ff_rtp_send_mpegvideo(AVFormatContext *s1, const uint8_t *buf1, int size) 30{ 31 RTPMuxContext *s = s1->priv_data; 32 int len, h, max_packet_size; 33 uint8_t *q; 34 int begin_of_slice, end_of_slice, frame_type, temporal_reference; 35 36 max_packet_size = s->max_payload_size; 37 begin_of_slice = 1; 38 end_of_slice = 0; 39 frame_type = 0; 40 temporal_reference = 0; 41 42 while (size > 0) { 43 int begin_of_sequence; 44 45 begin_of_sequence = 0; 46 len = max_packet_size - 4; 47 48 if (len >= size) { 49 len = size; 50 end_of_slice = 1; 51 } else { 52 const uint8_t *r, *r1; 53 int start_code; 54 55 r1 = buf1; 56 while (1) { 57 start_code = -1; 58 r = ff_find_start_code(r1, buf1 + size, &start_code); 59 if((start_code & 0xFFFFFF00) == 0x100) { 60 /* New start code found */ 61 if (start_code == 0x100) { 62 frame_type = (r[1] & 0x38) >> 3; 63 temporal_reference = (int)r[0] << 2 | r[1] >> 6; 64 } 65 if (start_code == 0x1B8) { 66 begin_of_sequence = 1; 67 } 68 69 if (r - buf1 - 4 <= len) { 70 /* The current slice fits in the packet */ 71 if (begin_of_slice == 0) { 72 /* no slice at the beginning of the packet... */ 73 end_of_slice = 1; 74 len = r - buf1 - 4; 75 break; 76 } 77 r1 = r; 78 } else { 79 if ((r1 - buf1 > 4) && (r - r1 < max_packet_size)) { 80 len = r1 - buf1 - 4; 81 end_of_slice = 1; 82 } 83 break; 84 } 85 } else { 86 break; 87 } 88 } 89 } 90 91 h = 0; 92 h |= temporal_reference << 16; 93 h |= begin_of_sequence << 13; 94 h |= begin_of_slice << 12; 95 h |= end_of_slice << 11; 96 h |= frame_type << 8; 97 98 q = s->buf; 99 *q++ = h >> 24; 100 *q++ = h >> 16; 101 *q++ = h >> 8; 102 *q++ = h; 103 104 memcpy(q, buf1, len); 105 q += len; 106 107 /* 90kHz time stamp */ 108 s->timestamp = s->cur_timestamp; 109 ff_rtp_send_data(s1, s->buf, q - s->buf, (len == size)); 110 111 buf1 += len; 112 size -= len; 113 begin_of_slice = end_of_slice; 114 end_of_slice = 0; 115 } 116} 117 118 119