FFmpeg/libavformat/rtpenc_aac.c
Luca Abeni e004d175fe rtpenc_aac: Fix calculation of the header size
Previously the high end byte was always set to zero. Also get
rid of an unnecessary multiplication (which in practice couldn't
overflow) before shifting.

Signed-off-by: Martin Storsjö <martin@martin.st>
2012-11-08 19:48:32 +02:00

86 lines
2.7 KiB
C

/*
* copyright (c) 2007 Luca Abeni
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; 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_aac(AVFormatContext *s1, const uint8_t *buff, int size)
{
RTPMuxContext *s = s1->priv_data;
int len, max_packet_size;
uint8_t *p;
const int max_frames_per_packet = s->max_frames_per_packet ? s->max_frames_per_packet : 5;
const int max_au_headers_size = 2 + 2 * max_frames_per_packet;
/* skip ADTS header, if present */
if ((s1->streams[0]->codec->extradata_size) == 0) {
size -= 7;
buff += 7;
}
max_packet_size = s->max_payload_size - max_au_headers_size;
/* test if the packet must be sent */
len = (s->buf_ptr - s->buf);
if ((s->num_frames == max_frames_per_packet) || (len && (len + size) > s->max_payload_size)) {
int au_size = s->num_frames * 2;
p = s->buf + max_au_headers_size - au_size - 2;
if (p != s->buf) {
memmove(p + 2, s->buf + 2, au_size);
}
/* Write the AU header size */
p[0] = au_size >> 5;
p[1] = (au_size & 0x1F) << 3;
ff_rtp_send_data(s1, p, s->buf_ptr - p, 1);
s->num_frames = 0;
}
if (s->num_frames == 0) {
s->buf_ptr = s->buf + max_au_headers_size;
s->timestamp = s->cur_timestamp;
}
if (size <= max_packet_size) {
p = s->buf + s->num_frames++ * 2 + 2;
*p++ = size >> 5;
*p = (size & 0x1F) << 3;
memcpy(s->buf_ptr, buff, size);
s->buf_ptr += size;
} else {
int au_size = size;
max_packet_size = s->max_payload_size - 4;
p = s->buf;
p[0] = 0;
p[1] = 16;
while (size > 0) {
len = FFMIN(size, max_packet_size);
p[2] = au_size >> 5;
p[3] = (au_size & 0x1F) << 3;
memcpy(p + 4, buff, len);
ff_rtp_send_data(s1, p, len + 4, len == size);
size -= len;
buff += len;
}
}
}