ffmpeg/libavformat/rtpenc_rfc4175.c

140 lines
4.2 KiB
C

/*
* RTP Packetization of RAW video (RFC4175)
* Copyright (c) 2021 Limin Wang
*
* 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
*/
#include "avformat.h"
#include "rtpenc.h"
void ff_rtp_send_raw_rfc4175(AVFormatContext *s1, const uint8_t *buf, int size, int interlaced, int field)
{
RTPMuxContext *s = s1->priv_data;
int width = s1->streams[0]->codecpar->width;
int height = s1->streams[0]->codecpar->height;
int xinc, yinc, pgroup;
int i = 0;
int offset = 0;
s->timestamp = s->cur_timestamp;
switch (s1->streams[0]->codecpar->format) {
case AV_PIX_FMT_UYVY422:
xinc = 2;
yinc = 1 << interlaced;
pgroup = 4;
break;
case AV_PIX_FMT_YUV422P10:
xinc = 2;
yinc = 1 << interlaced;
pgroup = 5;
break;
case AV_PIX_FMT_YUV420P:
xinc = 4;
yinc = 1 << interlaced;
pgroup = 6;
break;
case AV_PIX_FMT_RGB24:
xinc = 1;
yinc = 1 << interlaced;
pgroup = 3;
break;
case AV_PIX_FMT_BGR24:
xinc = 1;
yinc = 1 << interlaced;
pgroup = 3;
break;
default:
return;
}
while (i < height) {
int left = s->max_payload_size;
uint8_t *dest = s->buf;
uint8_t *headers;
const int head_size = 6;
int next_line;
int length, cont, pixels;
/* Extended Sequence Number */
*dest++ = 0;
*dest++ = 0;
left -= 2;
headers = dest;
do {
int l_line;
pixels = width - offset;
length = (pixels * pgroup) / xinc;
left -= head_size;
if (left >= length) {
next_line = 1;
} else {
pixels = (left / pgroup) * xinc;
length = (pixels * pgroup) / xinc;
next_line = 0;
}
left -= length;
/* Length */
*dest++ = (length >> 8) & 0xff;
*dest++ = length & 0xff;
/* Line No */
l_line = i >> interlaced;
*dest++ = ((l_line >> 8) & 0x7f) | ((field << 7) & 0x80);
*dest++ = l_line & 0xff;
if (next_line) i += yinc;
cont = (left > (head_size + pgroup) && i < height) ? 0x80 : 0x00;
/* Offset and Continuation marker */
*dest++ = ((offset >> 8) & 0x7f) | cont;
*dest++ = offset & 0xff;
if (next_line)
offset = 0;
else
offset += pixels;
} while (cont);
do {
int l_field;
int l_line;
int l_off;
int64_t copy_offset;
length = (headers[0] << 8) | headers[1];
l_field = (headers[2] & 0x80) >> 7;
l_line = ((headers[2] & 0x7f) << 8) | headers[3];
l_off = ((headers[4] & 0x7f) << 8) | headers[5];
cont = headers[4] & 0x80;
headers += head_size;
if (interlaced)
l_line = 2 * l_line + l_field;
copy_offset = (l_line * (int64_t)width + l_off) * pgroup / xinc;
if (copy_offset + length > size)
break;
memcpy (dest, buf + copy_offset, length);
dest += length;
} while (cont);
ff_rtp_send_data (s1, s->buf, s->max_payload_size - left, i >= height);
}
}