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authorDiego 'Flameeyes' Pettenò <flameeyes@gmail.com>2007-05-31 20:00:05 +0200
committerDiego 'Flameeyes' Pettenò <flameeyes@gmail.com>2007-05-31 20:00:05 +0200
commit2470724b1c7705870c00c206e1dda663fd419238 (patch)
treea696adc1674b9f23a4a3d33b91366e0f530563a0 /contrib/a52dec/bitstream.c
parentc043cbe458de70acbdb12afb97c20c6a00d416dd (diff)
downloadxine-lib-2470724b1c7705870c00c206e1dda663fd419238.tar.gz
xine-lib-2470724b1c7705870c00c206e1dda663fd419238.tar.bz2
Move liba52/a52dec sources inside contrib/a52dec.
--HG-- rename : src/liba52/a52.h => contrib/a52dec/a52.h rename : src/liba52/a52_internal.h => contrib/a52dec/a52_internal.h rename : src/liba52/bit_allocate.c => contrib/a52dec/bit_allocate.c rename : src/liba52/bitstream.c => contrib/a52dec/bitstream.c rename : src/liba52/bitstream.h => contrib/a52dec/bitstream.h rename : src/liba52/crc.c => contrib/a52dec/crc.c rename : src/liba52/diff_against_release.patch => contrib/a52dec/diff_against_release.patch rename : src/liba52/downmix.c => contrib/a52dec/downmix.c rename : src/liba52/imdct.c => contrib/a52dec/imdct.c rename : src/liba52/parse.c => contrib/a52dec/parse.c rename : src/liba52/tables.h => contrib/a52dec/tables.h
Diffstat (limited to 'contrib/a52dec/bitstream.c')
-rw-r--r--contrib/a52dec/bitstream.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/contrib/a52dec/bitstream.c b/contrib/a52dec/bitstream.c
new file mode 100644
index 000000000..04e8ca6d0
--- /dev/null
+++ b/contrib/a52dec/bitstream.c
@@ -0,0 +1,95 @@
+/*
+ * bitstream.c
+ * Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org>
+ * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
+ *
+ * This file is part of a52dec, a free ATSC A-52 stream decoder.
+ * See http://liba52.sourceforge.net/ for updates.
+ *
+ * a52dec 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.
+ *
+ * a52dec 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 <inttypes.h>
+
+#include "a52.h"
+#include "a52_internal.h"
+#include "bitstream.h"
+
+#define BUFFER_SIZE 4096
+
+void a52_bitstream_set_ptr (a52_state_t * state, uint8_t * buf)
+{
+ int align;
+
+ align = (long)buf & 3;
+ state->buffer_start = (uint32_t *) (buf - align);
+ state->bits_left = 0;
+ bitstream_get (state, align * 8);
+}
+
+static inline void bitstream_fill_current (a52_state_t * state)
+{
+ uint32_t tmp;
+
+ tmp = *(state->buffer_start++);
+ state->current_word = swab32 (tmp);
+}
+
+/*
+ * The fast paths for _get is in the
+ * bitstream.h header file so it can be inlined.
+ *
+ * The "bottom half" of this routine is suffixed _bh
+ *
+ * -ah
+ */
+
+uint32_t a52_bitstream_get_bh (a52_state_t * state, uint32_t num_bits)
+{
+ uint32_t result;
+
+ num_bits -= state->bits_left;
+ result = ((state->current_word << (32 - state->bits_left)) >>
+ (32 - state->bits_left));
+
+ bitstream_fill_current (state);
+
+ if (num_bits != 0)
+ result = (result << num_bits) | (state->current_word >> (32 - num_bits));
+
+ state->bits_left = 32 - num_bits;
+
+ return result;
+}
+
+int32_t a52_bitstream_get_bh_2 (a52_state_t * state, uint32_t num_bits)
+{
+ int32_t result;
+
+ num_bits -= state->bits_left;
+ result = ((((int32_t)state->current_word) << (32 - state->bits_left)) >>
+ (32 - state->bits_left));
+
+ bitstream_fill_current(state);
+
+ if (num_bits != 0)
+ result = (result << num_bits) | (state->current_word >> (32 - num_bits));
+
+ state->bits_left = 32 - num_bits;
+
+ return result;
+}