summaryrefslogtreecommitdiff
path: root/libavcodec/get_bits.h
diff options
context:
space:
mode:
Diffstat (limited to 'libavcodec/get_bits.h')
-rw-r--r--libavcodec/get_bits.h151
1 files changed, 114 insertions, 37 deletions
diff --git a/libavcodec/get_bits.h b/libavcodec/get_bits.h
index 66374f523d..d566b9c4d0 100644
--- a/libavcodec/get_bits.h
+++ b/libavcodec/get_bits.h
@@ -1,20 +1,20 @@
/*
* copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
*
- * This file is part of Libav.
+ * This file is part of FFmpeg.
*
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
@@ -31,6 +31,7 @@
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/log.h"
+#include "libavutil/avassert.h"
#include "mathops.h"
#include "vlc.h"
@@ -55,9 +56,7 @@ typedef struct GetBitContext {
const uint8_t *buffer, *buffer_end;
int index;
int size_in_bits;
-#if !UNCHECKED_BITSTREAM_READER
int size_in_bits_plus8;
-#endif
} GetBitContext;
/* Bitstream reader API docs:
@@ -101,6 +100,9 @@ typedef struct GetBitContext {
* LAST_SKIP_BITS(name, gb, num)
* Like SKIP_BITS, to be used if next call is UPDATE_CACHE or CLOSE_READER.
*
+ * BITS_LEFT(name, gb)
+ * Return the number of bits left
+ *
* For examples see get_bits, show_bits, skip_bits, get_vlc.
*/
@@ -112,7 +114,7 @@ typedef struct GetBitContext {
#define OPEN_READER_NOSIZE(name, gb) \
unsigned int name ## _index = (gb)->index; \
- unsigned int av_unused name ## _cache = 0
+ unsigned int av_unused name ## _cache
#if UNCHECKED_BITSTREAM_READER
#define OPEN_READER(name, gb) OPEN_READER_NOSIZE(name, gb)
@@ -128,27 +130,34 @@ typedef struct GetBitContext {
#define CLOSE_READER(name, gb) (gb)->index = name ## _index
+# ifdef LONG_BITSTREAM_READER
+
+# define UPDATE_CACHE_LE(name, gb) name ## _cache = \
+ AV_RL64((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
+
+# define UPDATE_CACHE_BE(name, gb) name ## _cache = \
+ AV_RB64((gb)->buffer + (name ## _index >> 3)) >> (32 - (name ## _index & 7))
+
+#else
+
+# define UPDATE_CACHE_LE(name, gb) name ## _cache = \
+ AV_RL32((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
+
+# define UPDATE_CACHE_BE(name, gb) name ## _cache = \
+ AV_RB32((gb)->buffer + (name ## _index >> 3)) << (name ## _index & 7)
+
+#endif
+
+
#ifdef BITSTREAM_READER_LE
-# ifdef LONG_BITSTREAM_READER
-# define UPDATE_CACHE(name, gb) name ## _cache = \
- AV_RL64((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
-# else
-# define UPDATE_CACHE(name, gb) name ## _cache = \
- AV_RL32((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
-# endif
+# define UPDATE_CACHE(name, gb) UPDATE_CACHE_LE(name, gb)
# define SKIP_CACHE(name, gb, num) name ## _cache >>= (num)
#else
-# ifdef LONG_BITSTREAM_READER
-# define UPDATE_CACHE(name, gb) name ## _cache = \
- AV_RB64((gb)->buffer + (name ## _index >> 3)) >> (32 - (name ## _index & 7))
-# else
-# define UPDATE_CACHE(name, gb) name ## _cache = \
- AV_RB32((gb)->buffer + (name ## _index >> 3)) << (name ## _index & 7)
-# endif
+# define UPDATE_CACHE(name, gb) UPDATE_CACHE_BE(name, gb)
# define SKIP_CACHE(name, gb, num) name ## _cache <<= (num)
@@ -161,6 +170,8 @@ typedef struct GetBitContext {
name ## _index = FFMIN(name ## _size_plus8, name ## _index + (num))
#endif
+#define BITS_LEFT(name, gb) ((int)((gb)->size_in_bits - name ## _index))
+
#define SKIP_BITS(name, gb, num) \
do { \
SKIP_CACHE(name, gb, num); \
@@ -169,12 +180,18 @@ typedef struct GetBitContext {
#define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
+#define SHOW_UBITS_LE(name, gb, num) zero_extend(name ## _cache, num)
+#define SHOW_SBITS_LE(name, gb, num) sign_extend(name ## _cache, num)
+
+#define SHOW_UBITS_BE(name, gb, num) NEG_USR32(name ## _cache, num)
+#define SHOW_SBITS_BE(name, gb, num) NEG_SSR32(name ## _cache, num)
+
#ifdef BITSTREAM_READER_LE
-# define SHOW_UBITS(name, gb, num) zero_extend(name ## _cache, num)
-# define SHOW_SBITS(name, gb, num) sign_extend(name ## _cache, num)
+# define SHOW_UBITS(name, gb, num) SHOW_UBITS_LE(name, gb, num)
+# define SHOW_SBITS(name, gb, num) SHOW_SBITS_LE(name, gb, num)
#else
-# define SHOW_UBITS(name, gb, num) NEG_USR32(name ## _cache, num)
-# define SHOW_SBITS(name, gb, num) NEG_SSR32(name ## _cache, num)
+# define SHOW_UBITS(name, gb, num) SHOW_UBITS_BE(name, gb, num)
+# define SHOW_SBITS(name, gb, num) SHOW_SBITS_BE(name, gb, num)
#endif
#define GET_CACHE(name, gb) ((uint32_t) name ## _cache)
@@ -194,7 +211,7 @@ static inline void skip_bits_long(GetBitContext *s, int n)
}
/**
- * Read MPEG-1 dc-style VLC (sign bit + mantisse with no MSB).
+ * Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
* if MSB not set it is negative
* @param n length in bits
*/
@@ -203,6 +220,7 @@ static inline int get_xbits(GetBitContext *s, int n)
register int sign;
register int32_t cache;
OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
cache = GET_CACHE(re, s);
sign = ~cache >> 31;
@@ -215,6 +233,7 @@ static inline int get_sbits(GetBitContext *s, int n)
{
register int tmp;
OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
tmp = SHOW_SBITS(re, s, n);
LAST_SKIP_BITS(re, s, n);
@@ -229,6 +248,7 @@ static inline unsigned int get_bits(GetBitContext *s, int n)
{
register int tmp;
OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
tmp = SHOW_UBITS(re, s, n);
LAST_SKIP_BITS(re, s, n);
@@ -244,6 +264,18 @@ static av_always_inline int get_bitsz(GetBitContext *s, int n)
return n ? get_bits(s, n) : 0;
}
+static inline unsigned int get_bits_le(GetBitContext *s, int n)
+{
+ register int tmp;
+ OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE_LE(re, s);
+ tmp = SHOW_UBITS_LE(re, s, n);
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+ return tmp;
+}
+
/**
* Show 1-25 bits.
*/
@@ -251,6 +283,7 @@ static inline unsigned int show_bits(GetBitContext *s, int n)
{
register int tmp;
OPEN_READER_NOSIZE(re, s);
+ av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
tmp = SHOW_UBITS(re, s, n);
return tmp;
@@ -259,7 +292,6 @@ static inline unsigned int show_bits(GetBitContext *s, int n)
static inline void skip_bits(GetBitContext *s, int n)
{
OPEN_READER(re, s);
- UPDATE_CACHE(re, s);
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
}
@@ -299,20 +331,22 @@ static inline void skip_bits1(GetBitContext *s)
*/
static inline unsigned int get_bits_long(GetBitContext *s, int n)
{
- if (n <= MIN_CACHE_BITS) {
+ if (!n) {
+ return 0;
+ } else if (n <= MIN_CACHE_BITS) {
return get_bits(s, n);
} else {
#ifdef BITSTREAM_READER_LE
- int ret = get_bits(s, 16);
+ unsigned ret = get_bits(s, 16);
return ret | (get_bits(s, n - 16) << 16);
#else
- int ret = get_bits(s, 16) << (n - 16);
+ unsigned ret = get_bits(s, 16) << (n - 16);
return ret | get_bits(s, n - 16);
#endif
}
}
-/*
+/**
* Read 0-64 bits.
*/
static inline uint64_t get_bits64(GetBitContext *s, int n)
@@ -351,6 +385,16 @@ static inline unsigned int show_bits_long(GetBitContext *s, int n)
}
}
+static inline int check_marker(void *logctx, GetBitContext *s, const char *msg)
+{
+ int bit = get_bits1(s);
+ if (!bit)
+ av_log(logctx, AV_LOG_INFO, "Marker bit missing at %d of %d %s\n",
+ get_bits_count(s) - 1, s->size_in_bits, msg);
+
+ return bit;
+}
+
/**
* Initialize GetBitContext.
* @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
@@ -365,7 +409,7 @@ static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
int buffer_size;
int ret = 0;
- if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {
+ if (bit_size >= INT_MAX - 7 || bit_size < 0 || !buffer) {
bit_size = 0;
buffer = NULL;
ret = AVERROR_INVALIDDATA;
@@ -375,9 +419,7 @@ static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
s->buffer = buffer;
s->size_in_bits = bit_size;
-#if !UNCHECKED_BITSTREAM_READER
s->size_in_bits_plus8 = bit_size + 8;
-#endif
s->buffer_end = buffer + buffer_size;
s->index = 0;
@@ -395,8 +437,8 @@ static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
static inline int init_get_bits8(GetBitContext *s, const uint8_t *buffer,
int byte_size)
{
- if (byte_size > INT_MAX / 8)
- return AVERROR_INVALIDDATA;
+ if (byte_size > INT_MAX / 8 || byte_size < 0)
+ byte_size = -1;
return init_get_bits(s, buffer, byte_size * 8);
}
@@ -445,7 +487,7 @@ static inline const uint8_t *align_get_bits(GetBitContext *s)
SKIP_BITS(name, gb, n); \
} while (0)
-#define GET_RL_VLC(level, run, name, gb, table, bits, \
+#define GET_RL_VLC_INTERNAL(level, run, name, gb, table, bits, \
max_depth, need_update) \
do { \
int n, nb_bits; \
@@ -528,6 +570,20 @@ static inline int get_bits_left(GetBitContext *gb)
return gb->size_in_bits - get_bits_count(gb);
}
+static inline int skip_1stop_8data_bits(GetBitContext *gb)
+{
+ if (get_bits_left(gb) <= 0)
+ return AVERROR_INVALIDDATA;
+
+ while (get_bits1(gb)) {
+ skip_bits(gb, 8);
+ if (get_bits_left(gb) <= 0)
+ return AVERROR_INVALIDDATA;
+ }
+
+ return 0;
+}
+
//#define TRACE
#ifdef TRACE
@@ -571,6 +627,25 @@ static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2],
return r;
}
+#define GET_RL_VLC(level, run, name, gb, table, bits, \
+ max_depth, need_update) \
+ do { \
+ int show = SHOW_UBITS(name, gb, 24); \
+ int len; \
+ int pos = name ## _index; \
+ \
+ GET_RL_VLC_INTERNAL(level, run, name, gb, table, bits,max_depth, need_update); \
+ \
+ len = name ## _index - pos + 1; \
+ show = show >> (24 - len); \
+ \
+ print_bin(show, len); \
+ \
+ av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d/%-3d rlv @%5d in %s %s:%d\n",\
+ show, len, run-1, level, pos, __FILE__, __PRETTY_FUNCTION__, __LINE__);\
+ } while (0) \
+
+
static inline int get_xbits_trace(GetBitContext *s, int n, const char *file,
const char *func, int line)
{
@@ -590,6 +665,8 @@ static inline int get_xbits_trace(GetBitContext *s, int n, const char *file,
#define get_vlc(s, vlc) get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__)
+#else //TRACE
+#define GET_RL_VLC GET_RL_VLC_INTERNAL
#endif
#endif /* AVCODEC_GET_BITS_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-01 08:31:10 +0000