gstreamer/ext/mpeg2enc/gstmpeg2encstreamwriter.cc

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/* GStreamer mpeg2enc (mjpegtools) wrapper
* (c) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
*
* gstmpeg2encstreamwriter.cc: GStreamer/mpeg2enc output wrapper
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstmpeg2encstreamwriter.hh"
#define BUFSIZE (128*1024)
/*
* Class init stuff.
*/
GstMpeg2EncStreamWriter::GstMpeg2EncStreamWriter (GstPad * in_pad, EncoderParams * params):
ElemStrmWriter (*params)
{
pad = in_pad;
buf = NULL;
}
/*
* Output functions.
*/
void
GstMpeg2EncStreamWriter::PutBits (guint32 val, gint n)
{
/* only relevant bits. Note that (according to Andrew),
* some CPUs do bitshifts modulo wordsize (32), which
* means that we have to check for n != 32 before
* bitshifting to the relevant bits (i.e. 0xffffffff <<
* 32 == 0xffffffff). */
if (n != 32)
val &= ~(0xffffffffU << n);
/* write data */
while (n >= outcnt) {
if (!buf) {
buf = gst_buffer_new_and_alloc (BUFSIZE);
GST_BUFFER_SIZE (buf) = 0;
}
outbfr = (outbfr << outcnt) | (val >> (n - outcnt));
GST_BUFFER_DATA (buf)[GST_BUFFER_SIZE (buf)++] = outbfr;
n -= outcnt;
outcnt = 8;
bytecnt++;
if (GST_BUFFER_SIZE (buf) >= GST_BUFFER_MAXSIZE (buf))
FrameFlush ();
}
/* cache remaining bits */
if (n != 0) {
outbfr = (outbfr << n) | val;
outcnt -= n;
}
}
void
GstMpeg2EncStreamWriter::FrameBegin ()
{
}
void
GstMpeg2EncStreamWriter::FrameFlush ()
{
if (buf) {
gst_pad_push (pad, GST_DATA (buf));
buf = NULL;
}
}
void
GstMpeg2EncStreamWriter::FrameDiscard ()
{
}