First stab at porting mplex

Original commit message from CVS:
First stab at porting mplex

1 files changed, 249 insertions, 0 deletions

diff --git a/ext/mplex/inputstrm.cc b/ext/mplex/inputstrm.cc
new file mode 100644
index 00000000..4a19724a
--- /dev/null
+++ b/ext/mplex/inputstrm.cc
@@ -0,0 +1,249 @@
+
+/*
+ *  inputstrm.c:  Base classes related to muxing out input streams 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 "fastintfns.h"
+#include "inputstrm.hh"
+#include "outputstream.hh"
+
+MuxStream::MuxStream ():init (false)
+{
+}
+
+
+void
+MuxStream::Init (const int strm_id,
+		 const unsigned int _buf_scale,
+		 const unsigned int buf_size,
+		 const unsigned int _zero_stuffing, bool bufs_in_first, bool always_bufs)
+{
+  stream_id = strm_id;
+  nsec = 0;
+  zero_stuffing = _zero_stuffing;
+  buffer_scale = _buf_scale;
+  buffer_size = buf_size;
+  bufmodel.Init (buf_size);
+  buffers_in_header = bufs_in_first;
+  always_buffers_in_header = always_bufs;
+  new_au_next_sec = true;
+  init = true;
+}
+
+
+
+unsigned int
+MuxStream::BufferSizeCode ()
+{
+  if (buffer_scale == 1)
+    return buffer_size / 1024;
+  else if (buffer_scale == 0)
+    return buffer_size / 128;
+  else
+    assert (false);
+}
+
+
+
+ElementaryStream::ElementaryStream (IBitStream & ibs, OutputStream & into, stream_kind _kind):
+InputStream (ibs), muxinto (into), kind (_kind), buffer_min (INT_MAX), buffer_max (1)
+{
+}
+
+
+bool ElementaryStream::NextAU ()
+{
+  Aunit *
+    p_au =
+    next ();
+
+  if (p_au != NULL) {
+    au = p_au;
+    au_unsent = p_au->length;
+    return true;
+  } else {
+    au_unsent = 0;
+    return false;
+  }
+}
+
+
+Aunit *
+ElementaryStream::Lookahead ()
+{
+  return aunits.lookahead ();
+}
+
+unsigned int
+ElementaryStream::BytesToMuxAUEnd (unsigned int sector_transport_size)
+{
+  return (au_unsent / min_packet_data) * sector_transport_size +
+    (au_unsent % min_packet_data) + (sector_transport_size - min_packet_data);
+}
+
+
+/******************************************************************
+ *	ElementaryStream::ReadPacketPayload
+ *
+ *  Reads the stream data from actual input stream, updates decode
+ *  buffer model and current access unit information from the
+ *  look-ahead scanning buffer to account for bytes_muxed bytes being
+ *  muxed out.  Particular important is the maintenance of "au_unsent"
+ *  the count of how much data in the current AU remains umuxed.  It
+ *  not only allows us to keep track of AU's but is also used for
+ *  generating substream headers
+ *
+ *  Unless we need to over-ride it to handle sub-stream headers
+ * The packet payload for an elementary stream is simply the parsed and
+ * spliced buffered stream data..
+ *
+ ******************************************************************/
+
+
+
+unsigned int
+ElementaryStream::ReadPacketPayload (uint8_t * dst, unsigned int to_read)
+{
+  unsigned int actually_read = bs.read_buffered_bytes (dst, to_read);
+
+  Muxed (actually_read);
+  return actually_read;
+}
+
+
+
+
+void
+ElementaryStream::Muxed (unsigned int bytes_muxed)
+{
+  clockticks decode_time;
+
+  if (bytes_muxed == 0 || MuxCompleted ())
+    return;
+
+
+  /* Work through what's left of the current AU and the following AU's
+     updating the info until we reach a point where an AU had to be
+     split between packets.
+     NOTE: It *is* possible for this loop to iterate. 
+
+     The DTS/PTS field for the packet in this case would have been
+     given the that for the first AU to start in the packet.
+     Whether Joe-Blow's hardware VCD player handles this properly is
+     another matter of course!
+   */
+
+  decode_time = RequiredDTS ();
+  while (au_unsent < bytes_muxed) {
+
+    bufmodel.Queued (au_unsent, decode_time);
+    bytes_muxed -= au_unsent;
+    if (!NextAU ())
+      return;
+    new_au_next_sec = true;
+    decode_time = RequiredDTS ();
+  };
+
+  // We've now reached a point where the current AU overran or
+  // fitted exactly.  We need to distinguish the latter case
+  // so we can record whether the next packet starts with an
+  // existing AU or not - info we need to decide what PTS/DTS
+  // info to write at the start of the next packet.
+
+  if (au_unsent > bytes_muxed) {
+
+    bufmodel.Queued (bytes_muxed, decode_time);
+    au_unsent -= bytes_muxed;
+    new_au_next_sec = false;
+  } else			//  if (au_unsent == bytes_muxed)
+  {
+    bufmodel.Queued (bytes_muxed, decode_time);
+    if (!NextAU ())
+      return;
+    new_au_next_sec = true;
+  }
+
+}
+
+bool
+ElementaryStream::MuxPossible (clockticks currentSCR)
+{
+  return (!RunOutComplete () && bufmodel.Space () > max_packet_data);
+}
+
+
+void
+ElementaryStream::UpdateBufferMinMax ()
+{
+  buffer_min = buffer_min < (int) bufmodel.Space ()? buffer_min : bufmodel.Space ();
+  buffer_max = buffer_max > (int) bufmodel.Space ()? buffer_max : bufmodel.Space ();
+}
+
+
+
+void
+ElementaryStream::AllDemuxed ()
+{
+  bufmodel.Flushed ();
+}
+
+void
+ElementaryStream::DemuxedTo (clockticks SCR)
+{
+  bufmodel.Cleaned (SCR);
+}
+
+bool
+ElementaryStream::MuxCompleted ()
+{
+  return au_unsent == 0;
+}
+
+void
+ElementaryStream::SetSyncOffset (clockticks sync_offset)
+{
+  timestamp_delay = sync_offset;
+}
+
+Aunit *
+ElementaryStream::next ()
+{
+  Aunit *res;
+
+  while (AUBufferNeedsRefill ()) {
+    FillAUbuffer (FRAME_CHUNK);
+  }
+  res = aunits.next ();
+  return res;
+}
+
+
+
+
+/* 
+ * Local variables:
+ *  c-file-style: "stroustrup"
+ *  tab-width: 4
+ *  indent-tabs-mode: nil
+ * End:
+ */