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/*
* audiostrm_out.cpp: Members of audio stream classes related to
* muxing out into the output stream.
*
* Copyright (C) 2001 Andrew Stevens <andrew.stevens@philips.com>
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <config.h>
#include <assert.h>
#include "mjpeg_types.h"
#include "audiostrm.hpp"
#include "multiplexor.hpp"
AudioStream::AudioStream(IBitStream &ibs, Multiplexor &into) :
ElementaryStream( ibs, into, ElementaryStream::audio ),
num_syncword(0)
{
FRAME_CHUNK = 24;
}
/*********************************
* Signals when audio stream has completed mux run-out specified
* in associated mux stream.
*********************************/
bool AudioStream::RunOutComplete()
{
return (au_unsent == 0 ||
( muxinto.running_out && RequiredPTS() >= muxinto.runout_PTS));
}
/******************************************************************
Output_Audio
generates Pack/Sys Header/Packet information from the
audio stream and saves them into the sector
******************************************************************/
void AudioStream::OutputSector ( )
{
clockticks PTS;
unsigned int max_packet_data;
unsigned int actual_payload;
unsigned int old_au_then_new_payload;
PTS = RequiredDTS();
old_au_then_new_payload =
muxinto.PacketPayload( *this, buffers_in_header, false, false );
bool last_packet = Lookahead() == 0;
// Ensure we have access units data buffered to allow a sector to be
// written.
max_packet_data = 0;
if( (muxinto.running_out && NextRequiredPTS() > muxinto.runout_PTS)
|| last_packet)
{
/* We're now in the last AU of a segment. So we don't want to
go beyond it's end when writing sectors. Hence we limit
packet payload size to (remaining) AU length.
*/
max_packet_data = au_unsent+StreamHeaderSize();
}
/* CASE: packet starts with new access unit */
if (new_au_next_sec)
{
actual_payload =
muxinto.WritePacket ( max_packet_data,
*this,
buffers_in_header, PTS, 0,
TIMESTAMPBITS_PTS);
}
/* CASE: packet starts with old access unit, no new one */
/* starts in this very same packet */
else if (!(new_au_next_sec) &&
(au_unsent >= old_au_then_new_payload))
{
actual_payload =
muxinto.WritePacket ( max_packet_data,
*this,
buffers_in_header, 0, 0,
TIMESTAMPBITS_NO );
}
/* CASE: packet starts with old access unit, a new one */
/* starts in this very same packet */
else /* !(new_au_next_sec) && (au_unsent < old_au_then_new_payload)) */
{
/* is there another access unit anyway ? */
if( !last_packet )
{
PTS = NextRequiredDTS();
actual_payload =
muxinto.WritePacket ( max_packet_data,
*this,
buffers_in_header, PTS, 0,
TIMESTAMPBITS_PTS );
}
else
{
actual_payload = muxinto.WritePacket ( max_packet_data,
*this,
buffers_in_header, 0, 0,
TIMESTAMPBITS_NO );
};
}
++nsec;
buffers_in_header = always_buffers_in_header;
}
/*
* Local variables:
* c-file-style: "stroustrup"
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/
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