/* * RTP packetization for H.264 (RFC3984) * Copyright (c) 2008 Luca Abeni * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * @brief H.264 packetization * @author Luca Abeni <lucabe72@email.it> */ #include "avformat.h" #include "avc.h" #include "rtpenc.h" static const uint8_t *avc_mp4_find_startcode(const uint8_t *start, const uint8_t *end, int nal_length_size) { int res = 0; if (end - start < nal_length_size) return NULL; while (nal_length_size--) res = (res << 8) | *start++; if (start + res > end || res < 0 || start + res < start) return NULL; return start + res; } static void nal_send(AVFormatContext *s1, const uint8_t *buf, int size, int last) { RTPMuxContext *s = s1->priv_data; av_log(s1, AV_LOG_DEBUG, "Sending NAL %x of len %d M=%d\n", buf[0] & 0x1F, size, last); if (size <= s->max_payload_size) { ff_rtp_send_data(s1, buf, size, last); } else { uint8_t type = buf[0] & 0x1F; uint8_t nri = buf[0] & 0x60; av_log(s1, AV_LOG_DEBUG, "NAL size %d > %d\n", size, s->max_payload_size); s->buf[0] = 28; /* FU Indicator; Type = 28 ---> FU-A */ s->buf[0] |= nri; s->buf[1] = type; s->buf[1] |= 1 << 7; buf += 1; size -= 1; while (size + 2 > s->max_payload_size) { memcpy(&s->buf[2], buf, s->max_payload_size - 2); ff_rtp_send_data(s1, s->buf, s->max_payload_size, 0); buf += s->max_payload_size - 2; size -= s->max_payload_size - 2; s->buf[1] &= ~(1 << 7); } s->buf[1] |= 1 << 6; memcpy(&s->buf[2], buf, size); ff_rtp_send_data(s1, s->buf, size + 2, last); } } void ff_rtp_send_h264(AVFormatContext *s1, const uint8_t *buf1, int size) { const uint8_t *r, *end = buf1 + size; RTPMuxContext *s = s1->priv_data; s->timestamp = s->cur_timestamp; if (s->nal_length_size) r = avc_mp4_find_startcode(buf1, end, s->nal_length_size) ? buf1 : end; else r = ff_avc_find_startcode(buf1, end); while (r < end) { const uint8_t *r1; if (s->nal_length_size) { r1 = avc_mp4_find_startcode(r, end, s->nal_length_size); if (!r1) r1 = end; r += s->nal_length_size; } else { while (!*(r++)); r1 = ff_avc_find_startcode(r, end); } nal_send(s1, r, r1 - r, r1 == end); r = r1; } }