* add support for liba52

Originally committed as revision 411 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 82 insertions, 0 deletions

diff --git a/libavcodec/liba52/bitstream.h b/libavcodec/liba52/bitstream.h
new file mode 100644
index 0000000000..8721428312
--- /dev/null
+++ b/libavcodec/liba52/bitstream.h
@@ -0,0 +1,82 @@
+/*
+ * bitstream.h
+ * 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
+ */
+
+/* (stolen from the kernel) */
+#ifdef WORDS_BIGENDIAN
+
+#	define swab32(x) (x)
+
+#else
+
+#	if 0 && defined (__i386__)
+
+#	define swab32(x) __i386_swab32(x)
+	static inline const uint32_t __i386_swab32(uint32_t x)
+	{
+		__asm__("bswap %0" : "=r" (x) : "0" (x));
+		return x;
+	}
+
+#	else
+
+#	define swab32(x)\
+((((uint8_t*)&x)[0] << 24) | (((uint8_t*)&x)[1] << 16) |  \
+ (((uint8_t*)&x)[2] << 8)  | (((uint8_t*)&x)[3]))
+
+#	endif
+#endif
+
+extern uint32_t a52_bits_left;
+extern uint32_t a52_current_word;
+
+void a52_bitstream_set_ptr (uint8_t * buf);
+uint32_t a52_bitstream_get_bh(uint32_t num_bits);
+int32_t a52_bitstream_get_bh_2(uint32_t num_bits);
+
+static inline uint32_t 
+bitstream_get(uint32_t num_bits)
+{
+    uint32_t result;
+	
+    if(num_bits < a52_bits_left) {
+	result = (a52_current_word << (32 - a52_bits_left)) >> (32 - num_bits);
+	a52_bits_left -= num_bits;
+	return result;
+    }
+
+    return a52_bitstream_get_bh(num_bits);
+}
+
+static inline int32_t 
+bitstream_get_2(uint32_t num_bits)
+{
+    int32_t result;
+	
+    if(num_bits < a52_bits_left) {
+	result = (((int32_t)a52_current_word) << (32 - a52_bits_left)) >> (32 - num_bits);
+	a52_bits_left -= num_bits;
+	return result;
+    }
+
+    return a52_bitstream_get_bh_2(num_bits);
+}