--- bitstream.h	2003/05/12 12:31:05	1.17.2.4
+++ bitstream.h	2010/12/28 19:19:57	1.25.2.1
@@ -3,25 +3,23 @@
  *  XVID MPEG-4 VIDEO CODEC
  *  - Bitstream reader/writer inlined functions and constants-
  *
- *  Copyright (C) 2001-2003 - Peter Ross <pross@xvid.org>
+ *  Copyright (C) 2001-2003 Peter Ross <pross@xvid.org>
  *
- *  This file is part of XviD, a free MPEG-4 video encoder/decoder
- *
- *  XviD is free software; you can redistribute it and/or modify it
- *  under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
+ *  This program is free software ; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation ; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  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
+ *  along with this program ; if not, write to the Free Software
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  *
- * $Id: bitstream.h,v 1.17.2.4 2003/05/12 12:31:05 suxen_drol Exp $
+ * $Id: bitstream.h,v 1.25.2.1 2010/12/28 19:19:57 Isibaar Exp $
  *
  ****************************************************************************/
 
@@ -118,10 +116,10 @@
  * Prototypes
  ****************************************************************************/
 
-int read_video_packet_header(Bitstream *bs, 
-							 DECODER * dec, 
-							 const int addbits, 
-							 int *quant, 
+int read_video_packet_header(Bitstream *bs,
+							 DECODER * dec,
+							 const int addbits,
+							 int *quant,
 							 int *fcode_forward,
 							 int *fcode_backward,
 							 int *intra_dc_threshold);
@@ -130,7 +128,6 @@
 int BitstreamReadHeaders(Bitstream * bs,
 						 DECODER * dec,
 						 uint32_t * rounding,
-						 uint32_t * reduced_resolution,
 						 uint32_t * quant,
 						 uint32_t * fcode_forward,
 						 uint32_t * fcode_backward,
@@ -139,16 +136,42 @@
 
 
 void BitstreamWriteVolHeader(Bitstream * const bs,
-							 const MBParam * pParam);
+							 const MBParam * pParam,
+							 const FRAMEINFO * const frame,
+							 const int num_slices);
 
 void BitstreamWriteVopHeader(Bitstream * const bs,
 							 const MBParam * pParam,
 							 const FRAMEINFO * const frame,
-							 int vop_coded);
+							 int vop_coded,
+							 unsigned int quant);
+
+void BitstreamWriteUserData(Bitstream * const bs,
+							const char *data,
+							const unsigned int length);
+
+void
+BitstreamWriteEndOfSequence(Bitstream * const bs);
+
+void
+BitstreamWriteGroupOfVopHeader(Bitstream * const bs,
+                               const MBParam * pParam,
+                               uint32_t is_closed_gov);
+
+void write_video_packet_header(Bitstream * const bs,
+                               const MBParam * pParam,
+                               const FRAMEINFO * const frame,
+                               int mbnum);
+
+/*****************************************************************************
+ * Bitstream
+ ****************************************************************************/
 
-void BitstreamWriteUserData(Bitstream * const bs, 
-							uint8_t * data, 
-							const int length);
+/* Input buffer should be readable as full chunks of 8bytes, including
+the end of the buffer. Padding might be appropriate. If only chunks
+of 4bytes are applicable, define XVID_SAFE_BS_TAIL. Note that this will
+slow decoding, so consider this as a last-resort solution */
+/* #define XVID_SAFE_BS_TAIL */
 
 /* initialise bitstream structure */
 
@@ -181,8 +204,12 @@
 #endif
 	bs->bufb = tmp;
 
-	bs->buf = 0;
-	bs->pos = bs->initpos = bitpos*8;
+	bs->pos = bs->initpos = (uint32_t) bitpos*8;
+	/* preserve the intervening bytes */
+	if (bs->initpos > 0)
+		bs->buf = bs->bufa & (0xffffffff << (32 - bs->initpos));
+	else
+		bs->buf = 0;
 	bs->length = length;
 }
 
@@ -208,7 +235,11 @@
 #endif
 	bs->bufb = tmp;
 
-	bs->buf = 0;
+	/* preserve the intervening bytes */
+	if (bs->initpos > 0)
+		bs->buf = bs->bufa & (0xffffffff << (32 - bs->initpos));
+	else
+		bs->buf = 0;
 	bs->pos = bs->initpos;
 }
 
@@ -243,19 +274,29 @@
 		uint32_t tmp;
 
 		bs->bufa = bs->bufb;
-		tmp = *((uint32_t *) bs->tail + 2);
+#if defined(XVID_SAFE_BS_TAIL)
+		if (bs->tail<(bs->start+((bs->length+3)>>2)))
+#endif
+		{
+			tmp = *((uint32_t *) bs->tail + 2);
 #ifndef ARCH_IS_BIG_ENDIAN
-		BSWAP(tmp);
+			BSWAP(tmp);
+#endif
+			bs->bufb = tmp;
+			bs->tail++;
+		}
+#if defined(XVID_SAFE_BS_TAIL)
+		else {
+			bs->bufb = 0;
+		}
 #endif
-		bs->bufb = tmp;
-		bs->tail++;
 		bs->pos -= 32;
 	}
 }
 
 
 /* number of bits to next byte alignment */
-static __inline uint32_t 
+static __inline uint32_t
 BitstreamNumBitsToByteAlign(Bitstream *bs)
 {
 	uint32_t n = (32 - bs->pos) % 8;
@@ -442,7 +483,7 @@
 
 
 /*
- * pad bitstream to the next byte boundary 
+ * pad bitstream to the next byte boundary
  * alway pad: even if currently at the byte boundary
  */