libavformat/rtpenc_h264.c

   1 /*
   2  * RTP packetization for H.264 (RFC3984)
   3  * Copyright (c) 2008 Luca Abeni.
   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 /**
  23  * @file rtpenc_h264.c
  24  * @brief H.264 packetization
  25  * @author Luca Abeni <lucabe72@email.it>
  26  */
  27
  28 #include "avformat.h"
  29 #include "avc.h"
  30 #include "rtp_h264.h"
  31
  32 static void nal_send(AVFormatContext *s1, const uint8_t *buf, int size, int last)
  33 {
  34     RTPDemuxContext *s = s1->priv_data;
  35
  36     av_log(s1, AV_LOG_DEBUG, "Sending NAL %x of len %d M=%d\n", buf[0] & 0x1F, size, last);
  37     if (size <= s->max_payload_size) {
  38         ff_rtp_send_data(s1, buf, size, last);
  39     } else {
  40         uint8_t type = buf[0] & 0x1F;
  41         uint8_t nri = buf[0] & 0x60;
  42
  43         av_log(s1, AV_LOG_DEBUG, "NAL size %d > %d\n", size, s->max_payload_size);
  44         s->buf[0] = 28;        /* FU Indicator; Type = 28 ---> FU-A */
  45         s->buf[0] |= nri;
  46         s->buf[1] = type;
  47         s->buf[1] |= 1 << 7;
  48         buf += 1;
  49         size -= 1;
  50         while (size + 2 > s->max_payload_size) {
  51             memcpy(&s->buf[2], buf, s->max_payload_size - 2);
  52             ff_rtp_send_data(s1, s->buf, s->max_payload_size, 0);
  53             buf += s->max_payload_size - 2;
  54             size -= s->max_payload_size - 2;
  55             s->buf[1] &= ~(1 << 7);
  56         }
  57         s->buf[1] |= 1 << 6;
  58         memcpy(&s->buf[2], buf, size);
  59         ff_rtp_send_data(s1, s->buf, size + 2, 1);
  60     }
  61 }
  62
  63 void ff_rtp_send_h264(AVFormatContext *s1, const uint8_t *buf1, int size)
  64 {
  65     const uint8_t *r;
  66     RTPDemuxContext *s = s1->priv_data;
  67
  68     s->timestamp = s->cur_timestamp;
  69     r = ff_avc_find_startcode(buf1, buf1 + size);
  70     while (r < buf1 + size) {
  71         const uint8_t *r1;
  72
  73         while(!*(r++));
  74         r1 = ff_avc_find_startcode(r, buf1 + size);
  75         nal_send(s1, r, r1 - r, (r1 == buf1 + size));
  76         r = r1;
  77     }
  78 }