gstreamer/gst/rtp/dboolhuff.c
Vincent Penquerc'h 88aade4150 rtpvp8: fix bitstream parsing using the wrong kind of bitreader
VP8 uses a probabilistic bool coder, not a straight bit coder.
This fixes parsing when error-resilient is set.

This commit includes a copy of libvpx's bool coder, BSD licensed.

https://bugzilla.gnome.org/show_bug.cgi?id=652694
2012-11-01 20:53:47 +00:00

68 lines
2 KiB
C

/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the dboolhuff.LICENSE file in this directory.
* See the libvpx original distribution for more information,
* including patent information, and author information.
*/
#include "dboolhuff.h"
const unsigned char vp8_norm[256] __attribute__ ((aligned (16))) = {
0, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int
vp8dx_start_decode (BOOL_DECODER * br,
const unsigned char *source, unsigned int source_sz)
{
br->user_buffer_end = source + source_sz;
br->user_buffer = source;
br->value = 0;
br->count = -8;
br->range = 255;
if (source_sz && !source)
return 1;
/* Populate the buffer */
vp8dx_bool_decoder_fill (br);
return 0;
}
void
vp8dx_bool_decoder_fill (BOOL_DECODER * br)
{
const unsigned char *bufptr;
const unsigned char *bufend;
VP8_BD_VALUE value;
int count;
bufend = br->user_buffer_end;
bufptr = br->user_buffer;
value = br->value;
count = br->count;
VP8DX_BOOL_DECODER_FILL (count, value, bufptr, bufend);
br->user_buffer = bufptr;
br->value = value;
br->count = count;
}