--- /dev/null
- * This file is part of Libav.
+ /*
+ * RTP packetization for H.264 (RFC3984)
+ * RTP packetizer for HEVC/H.265 payload format (draft version 6)
+ * Copyright (c) 2008 Luca Abeni
+ * Copyright (c) 2014 Thomas Volkert <thomas@homer-conferencing.com>
+ *
- * Libav is free software; you can redistribute it and/or
++ * This file is part of FFmpeg.
+ *
- * Libav is distributed in the hope that it will be useful,
++ * 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.
+ *
- * License along with Libav; if not, write to the Free Software
++ * 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/HEVC packetization
+ * @author Luca Abeni <lucabe72@email.it>
+ */
+
+ #include "libavutil/intreadwrite.h"
+
+ #include "avformat.h"
+ #include "avc.h"
+ #include "rtpenc.h"
+
+ static void flush_buffered(AVFormatContext *s1, int last)
+ {
+ RTPMuxContext *s = s1->priv_data;
+ if (s->buf_ptr != s->buf) {
+ // If we're only sending one single NAL unit, send it as such, skip
+ // the STAP-A/AP framing
+ if (s->buffered_nals == 1) {
+ enum AVCodecID codec = s1->streams[0]->codec->codec_id;
+ if (codec == AV_CODEC_ID_H264)
+ ff_rtp_send_data(s1, s->buf + 3, s->buf_ptr - s->buf - 3, last);
+ else
+ ff_rtp_send_data(s1, s->buf + 4, s->buf_ptr - s->buf - 4, last);
+ } else
+ ff_rtp_send_data(s1, s->buf, s->buf_ptr - s->buf, last);
+ }
+ s->buf_ptr = s->buf;
+ s->buffered_nals = 0;
+ }
+
+ static void nal_send(AVFormatContext *s1, const uint8_t *buf, int size, int last)
+ {
+ RTPMuxContext *s = s1->priv_data;
+ enum AVCodecID codec = s1->streams[0]->codec->codec_id;
+
+ 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) {
+ int buffered_size = s->buf_ptr - s->buf;
+ int header_size;
+ int skip_aggregate = 0;
+
+ if (codec == AV_CODEC_ID_H264) {
+ header_size = 1;
+ skip_aggregate = s->flags & FF_RTP_FLAG_H264_MODE0;
+ } else {
+ header_size = 2;
+ }
+
+ // Flush buffered NAL units if the current unit doesn't fit
+ if (buffered_size + 2 + size > s->max_payload_size) {
+ flush_buffered(s1, 0);
+ buffered_size = 0;
+ }
+ // If we aren't using mode 0, and the NAL unit fits including the
+ // framing (2 bytes length, plus 1/2 bytes for the STAP-A/AP marker),
+ // write the unit to the buffer as a STAP-A/AP packet, otherwise flush
+ // and send as single NAL.
+ if (buffered_size + 2 + header_size + size <= s->max_payload_size &&
+ !skip_aggregate) {
+ if (buffered_size == 0) {
+ if (codec == AV_CODEC_ID_H264) {
+ *s->buf_ptr++ = 24;
+ } else {
+ *s->buf_ptr++ = 48 << 1;
+ *s->buf_ptr++ = 1;
+ }
+ }
+ AV_WB16(s->buf_ptr, size);
+ s->buf_ptr += 2;
+ memcpy(s->buf_ptr, buf, size);
+ s->buf_ptr += size;
+ s->buffered_nals++;
+ } else {
+ flush_buffered(s1, 0);
+ ff_rtp_send_data(s1, buf, size, last);
+ }
+ } else {
+ int flag_byte, header_size;
+ flush_buffered(s1, 0);
+ if (codec == AV_CODEC_ID_H264 && (s->flags & FF_RTP_FLAG_H264_MODE0)) {
+ av_log(s1, AV_LOG_ERROR,
+ "NAL size %d > %d, try -slice-max-size %d\n", size,
+ s->max_payload_size, s->max_payload_size);
+ return;
+ }
+ av_log(s1, AV_LOG_DEBUG, "NAL size %d > %d\n", size, s->max_payload_size);
+ if (codec == AV_CODEC_ID_H264) {
+ uint8_t type = buf[0] & 0x1F;
+ uint8_t nri = buf[0] & 0x60;
+
+ 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;
+
+ flag_byte = 1;
+ header_size = 2;
+ } else {
+ uint8_t nal_type = (buf[0] >> 1) & 0x3F;
+ /*
+ * create the HEVC payload header and transmit the buffer as fragmentation units (FU)
+ *
+ * 0 1
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |F| Type | LayerId | TID |
+ * +-------------+-----------------+
+ *
+ * F = 0
+ * Type = 49 (fragmentation unit (FU))
+ * LayerId = 0
+ * TID = 1
+ */
+ s->buf[0] = 49 << 1;
+ s->buf[1] = 1;
+
+ /*
+ * create the FU header
+ *
+ * 0 1 2 3 4 5 6 7
+ * +-+-+-+-+-+-+-+-+
+ * |S|E| FuType |
+ * +---------------+
+ *
+ * S = variable
+ * E = variable
+ * FuType = NAL unit type
+ */
+ s->buf[2] = nal_type;
+ /* set the S bit: mark as start fragment */
+ s->buf[2] |= 1 << 7;
+
+ /* pass the original NAL header */
+ buf += 2;
+ size -= 2;
+
+ flag_byte = 2;
+ header_size = 3;
+ }
+
+ while (size + header_size > s->max_payload_size) {
+ memcpy(&s->buf[header_size], buf, s->max_payload_size - header_size);
+ ff_rtp_send_data(s1, s->buf, s->max_payload_size, 0);
+ buf += s->max_payload_size - header_size;
+ size -= s->max_payload_size - header_size;
+ s->buf[flag_byte] &= ~(1 << 7);
+ }
+ s->buf[flag_byte] |= 1 << 6;
+ memcpy(&s->buf[header_size], buf, size);
+ ff_rtp_send_data(s1, s->buf, size + header_size, last);
+ }
+ }
+
+ void ff_rtp_send_h264_hevc(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;
+ s->buf_ptr = s->buf;
+ if (s->nal_length_size)
+ r = ff_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 = ff_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;
+ }
+ flush_buffered(s1, 1);
+ }
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