#define AVCODEC_GET_BITS_H
#include <stdint.h>
+
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/log.h"
} RL_VLC_ELEM;
/* Bitstream reader API docs:
-name
- arbitrary name which is used as prefix for the internal variables
-
-gb
- getbitcontext
-
-OPEN_READER(name, gb)
- load gb into local variables
-
-CLOSE_READER(name, gb)
- store local vars in gb
-
-UPDATE_CACHE(name, gb)
- refill the internal cache from the bitstream
- after this call at least MIN_CACHE_BITS will be available,
-
-GET_CACHE(name, gb)
- will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit)
-
-SHOW_UBITS(name, gb, num)
- will return the next num bits
-
-SHOW_SBITS(name, gb, num)
- will return the next num bits and do sign extension
-
-SKIP_BITS(name, gb, num)
- will skip over the next num bits
- note, this is equivalent to SKIP_CACHE; SKIP_COUNTER
-
-SKIP_CACHE(name, gb, num)
- will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER)
-
-SKIP_COUNTER(name, gb, num)
- will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS)
-
-LAST_SKIP_BITS(name, gb, num)
- like SKIP_BITS, to be used if next call is UPDATE_CACHE or CLOSE_READER
-
-for examples see get_bits, show_bits, skip_bits, get_vlc
-*/
+ * name
+ * arbitrary name which is used as prefix for the internal variables
+ *
+ * gb
+ * getbitcontext
+ *
+ * OPEN_READER(name, gb)
+ * load gb into local variables
+ *
+ * CLOSE_READER(name, gb)
+ * store local vars in gb
+ *
+ * UPDATE_CACHE(name, gb)
+ * Refill the internal cache from the bitstream.
+ * After this call at least MIN_CACHE_BITS will be available.
+ *
+ * GET_CACHE(name, gb)
+ * Will output the contents of the internal cache,
+ * next bit is MSB of 32 or 64 bit (FIXME 64bit).
+ *
+ * SHOW_UBITS(name, gb, num)
+ * Will return the next num bits.
+ *
+ * SHOW_SBITS(name, gb, num)
+ * Will return the next num bits and do sign extension.
+ *
+ * SKIP_BITS(name, gb, num)
+ * Will skip over the next num bits.
+ * Note, this is equivalent to SKIP_CACHE; SKIP_COUNTER.
+ *
+ * SKIP_CACHE(name, gb, num)
+ * Will remove the next num bits from the cache (note SKIP_COUNTER
+ * MUST be called before UPDATE_CACHE / CLOSE_READER).
+ *
+ * SKIP_COUNTER(name, gb, num)
+ * Will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS).
+ *
+ * LAST_SKIP_BITS(name, gb, num)
+ * Like SKIP_BITS, to be used if next call is UPDATE_CACHE or CLOSE_READER.
+ *
+ * For examples see get_bits, show_bits, skip_bits, get_vlc.
+ */
#ifdef LONG_BITSTREAM_READER
# define MIN_CACHE_BITS 32
# define MIN_CACHE_BITS 25
#endif
+#if UNCHECKED_BITSTREAM_READER
#define OPEN_READER(name, gb) \
- unsigned int name##_index = (gb)->index; \
- unsigned int av_unused name##_cache = 0
+ unsigned int name ## _index = (gb)->index; \
+ unsigned int av_unused name ## _cache = 0
-#define CLOSE_READER(name, gb) (gb)->index = name##_index
+#define HAVE_BITS_REMAINING(name, gb) 1
+#else
+#define OPEN_READER(name, gb) \
+ unsigned int name ## _index = (gb)->index; \
+ unsigned int av_unused name ## _cache = 0; \
+ unsigned int av_unused name ## _size_plus8 = (gb)->size_in_bits_plus8
+
+#define HAVE_BITS_REMAINING(name, gb) name ## _index < name ## _size_plus8
+#endif
+
+#define CLOSE_READER(name, gb) (gb)->index = name ## _index
#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)
+# 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)
+# define UPDATE_CACHE(name, gb) name ## _cache = \
+ AV_RL32((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
# endif
-# define SKIP_CACHE(name, gb, num) name##_cache >>= (num)
+# 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))
+# 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)
+# define UPDATE_CACHE(name, gb) name ## _cache = \
+ AV_RB32((gb)->buffer + (name ## _index >> 3)) << (name ## _index & 7)
# endif
-# define SKIP_CACHE(name, gb, num) name##_cache <<= (num)
+# define SKIP_CACHE(name, gb, num) name ## _cache <<= (num)
#endif
#if UNCHECKED_BITSTREAM_READER
-# define SKIP_COUNTER(name, gb, num) name##_index += (num)
+# define SKIP_COUNTER(name, gb, num) name ## _index += (num)
#else
# define SKIP_COUNTER(name, gb, num) \
- name##_index = FFMIN((gb)->size_in_bits_plus8, name##_index + (num))
+ name ## _index = FFMIN(name ## _size_plus8, name ## _index + (num))
#endif
-#define SKIP_BITS(name, gb, num) do { \
+#define SKIP_BITS(name, gb, num) \
+ do { \
SKIP_CACHE(name, gb, num); \
SKIP_COUNTER(name, gb, num); \
} while (0)
#define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, 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) zero_extend(name ## _cache, num)
+# define SHOW_SBITS(name, gb, num) sign_extend(name ## _cache, 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) NEG_USR32(name ## _cache, num)
+# define SHOW_SBITS(name, gb, num) NEG_SSR32(name ## _cache, num)
#endif
-#define GET_CACHE(name, gb) ((uint32_t)name##_cache)
+#define GET_CACHE(name, gb) ((uint32_t) name ## _cache)
static inline int get_bits_count(const GetBitContext *s)
{
return s->index;
}
-static inline void skip_bits_long(GetBitContext *s, int n){
+static inline void skip_bits_long(GetBitContext *s, int n)
+{
#if UNCHECKED_BITSTREAM_READER
s->index += n;
#else
OPEN_READER(re, s);
UPDATE_CACHE(re, s);
cache = GET_CACHE(re, s);
- sign = ~cache >> 31;
+ sign = ~cache >> 31;
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
static inline unsigned int get_bits1(GetBitContext *s)
{
unsigned int index = s->index;
- uint8_t result = s->buffer[index>>3];
+ uint8_t result = s->buffer[index >> 3];
#ifdef BITSTREAM_READER_LE
result >>= index & 7;
- result &= 1;
+ result &= 1;
#else
result <<= index & 7;
result >>= 8 - 1;
*/
static inline unsigned int get_bits_long(GetBitContext *s, int n)
{
- if (n <= MIN_CACHE_BITS)
+ if (n <= MIN_CACHE_BITS) {
return get_bits(s, n);
- else {
+ } else {
#ifdef BITSTREAM_READER_LE
int ret = get_bits(s, 16);
- return ret | (get_bits(s, n-16) << 16);
+ return ret | (get_bits(s, n - 16) << 16);
#else
- int ret = get_bits(s, 16) << (n-16);
- return ret | get_bits(s, n-16);
+ int 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)
+{
+ if (n <= 32) {
+ return get_bits_long(s, n);
+ } else {
+#ifdef BITSTREAM_READER_LE
+ uint64_t ret = get_bits_long(s, 32);
+ return ret | (uint64_t) get_bits_long(s, n - 32) << 32;
+#else
+ uint64_t ret = (uint64_t) get_bits_long(s, n - 32) << 32;
+ return ret | get_bits_long(s, 32);
#endif
}
}
*/
static inline unsigned int show_bits_long(GetBitContext *s, int n)
{
- if (n <= MIN_CACHE_BITS)
+ if (n <= MIN_CACHE_BITS) {
return show_bits(s, n);
- else {
+ } else {
GetBitContext gb = *s;
return get_bits_long(&gb, n);
}
}
/**
- * Inititalize GetBitContext.
- * @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger than the actual read bits
- * because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
+ * Initialize GetBitContext.
+ * @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes
+ * larger than the actual read bits because some optimized bitstream
+ * readers read 32 or 64 bit at once and could read over the end
* @param bit_size the size of the buffer in bits
+ * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
*/
-static inline void init_get_bits(GetBitContext *s, const uint8_t *buffer,
- int bit_size)
+static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
+ int bit_size)
{
- int buffer_size = (bit_size+7)>>3;
- if (buffer_size < 0 || bit_size < 0) {
+ int buffer_size;
+ int ret = 0;
+
+ if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {
buffer_size = bit_size = 0;
- buffer = NULL;
+ buffer = NULL;
+ ret = AVERROR_INVALIDDATA;
}
- s->buffer = buffer;
- s->size_in_bits = bit_size;
+ buffer_size = (bit_size + 7) >> 3;
+
+ 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;
+ s->buffer_end = buffer + buffer_size;
+ s->index = 0;
+
+ return ret;
+}
+
+/**
+ * Initialize GetBitContext.
+ * @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes
+ * larger than the actual read bits because some optimized bitstream
+ * readers read 32 or 64 bit at once and could read over the end
+ * @param byte_size the size of the buffer in bytes
+ * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
+ */
+static inline int init_get_bits8(GetBitContext *s, const uint8_t *buffer,
+ int byte_size)
+{
+ if (byte_size > INT_MAX / 8)
+ return AVERROR_INVALIDDATA;
+ return init_get_bits(s, buffer, byte_size * 8);
}
static inline void align_get_bits(GetBitContext *s)
{
int n = -get_bits_count(s) & 7;
- if (n) skip_bits(s, n);
+ if (n)
+ skip_bits(s, n);
}
#define init_vlc(vlc, nb_bits, nb_codes, \
bits, bits_wrap, bits_size, \
codes, codes_wrap, codes_size, \
flags) \
- ff_init_vlc_sparse(vlc, nb_bits, nb_codes, \
- bits, bits_wrap, bits_size, \
- codes, codes_wrap, codes_size, \
- NULL, 0, 0, flags)
+ ff_init_vlc_sparse(vlc, nb_bits, nb_codes, \
+ bits, bits_wrap, bits_size, \
+ codes, codes_wrap, codes_size, \
+ NULL, 0, 0, flags)
int ff_init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes,
- const void *bits, int bits_wrap, int bits_size,
- const void *codes, int codes_wrap, int codes_size,
- const void *symbols, int symbols_wrap, int symbols_size,
- int flags);
-#define INIT_VLC_LE 2
-#define INIT_VLC_USE_NEW_STATIC 4
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int flags);
void ff_free_vlc(VLC *vlc);
-#define INIT_VLC_STATIC(vlc, bits, a,b,c,d,e,f,g, static_size) do { \
- static VLC_TYPE table[static_size][2]; \
- (vlc)->table = table; \
- (vlc)->table_allocated = static_size; \
- init_vlc(vlc, bits, a,b,c,d,e,f,g, INIT_VLC_USE_NEW_STATIC); \
- } while (0)
+#define INIT_VLC_LE 2
+#define INIT_VLC_USE_NEW_STATIC 4
+#define INIT_VLC_STATIC(vlc, bits, a, b, c, d, e, f, g, static_size) \
+ do { \
+ static VLC_TYPE table[static_size][2]; \
+ (vlc)->table = table; \
+ (vlc)->table_allocated = static_size; \
+ init_vlc(vlc, bits, a, b, c, d, e, f, g, INIT_VLC_USE_NEW_STATIC); \
+ } while (0)
/**
* If the vlc code is invalid and max_depth=1, then no bits will be removed.
SKIP_BITS(name, gb, n); \
} while (0)
-#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update) \
- do { \
- int n, nb_bits; \
- unsigned int index; \
- \
- index = SHOW_UBITS(name, gb, bits); \
- level = table[index].level; \
- n = table[index].len; \
- \
- if (max_depth > 1 && n < 0) { \
- SKIP_BITS(name, gb, bits); \
- if (need_update) { \
- UPDATE_CACHE(name, gb); \
- } \
- \
- nb_bits = -n; \
- \
- index = SHOW_UBITS(name, gb, nb_bits) + level; \
- level = table[index].level; \
- n = table[index].len; \
- } \
- run = table[index].run; \
- SKIP_BITS(name, gb, n); \
+#define GET_RL_VLC(level, run, name, gb, table, bits, \
+ max_depth, need_update) \
+ do { \
+ int n, nb_bits; \
+ unsigned int index; \
+ \
+ index = SHOW_UBITS(name, gb, bits); \
+ level = table[index].level; \
+ n = table[index].len; \
+ \
+ if (max_depth > 1 && n < 0) { \
+ SKIP_BITS(name, gb, bits); \
+ if (need_update) { \
+ UPDATE_CACHE(name, gb); \
+ } \
+ \
+ nb_bits = -n; \
+ \
+ index = SHOW_UBITS(name, gb, nb_bits) + level; \
+ level = table[index].level; \
+ n = table[index].len; \
+ } \
+ run = table[index].run; \
+ SKIP_BITS(name, gb, n); \
} while (0)
-
/**
* Parse a vlc code.
* @param bits is the number of bits which will be read at once, must be
GET_VLC(code, re, s, table, bits, max_depth);
CLOSE_READER(re, s);
+
return code;
}
{
int i;
- for (i = n-1; i >= 0; i--) {
- av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1);
- }
+ for (i = n - 1; i >= 0; i--)
+ av_log(NULL, AV_LOG_DEBUG, "%d", (bits >> i) & 1);
for (i = n; i < 24; i++)
av_log(NULL, AV_LOG_DEBUG, " ");
}
-static inline int get_bits_trace(GetBitContext *s, int n, char *file,
+static inline int get_bits_trace(GetBitContext *s, int n, const char *file,
const char *func, int line)
{
int r = get_bits(s, n);
print_bin(r, n);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n",
- r, n, r, get_bits_count(s)-n, file, func, line);
+ r, n, r, get_bits_count(s) - n, file, func, line);
+
return r;
}
+
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2],
- int bits, int max_depth, char *file,
+ int bits, int max_depth, const char *file,
const char *func, int line)
{
int show = show_bits(s, 24);
int pos = get_bits_count(s);
int r = get_vlc2(s, table, bits, max_depth);
int len = get_bits_count(s) - pos;
- int bits2 = show >> (24-len);
+ int bits2 = show >> (24 - len);
print_bin(bits2, len);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n",
bits2, len, r, pos, file, func, line);
+
return r;
}
-static inline int get_xbits_trace(GetBitContext *s, int n, char *file,
+
+static inline int get_xbits_trace(GetBitContext *s, int n, const char *file,
const char *func, int line)
{
int show = show_bits(s, n);
print_bin(show, n);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n",
- show, n, r, get_bits_count(s)-n, file, func, line);
+ show, n, r, get_bits_count(s) - n, file, func, line);
+
return r;
}
-#define get_bits(s, n) get_bits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
-#define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__)
+#define get_bits(s, n) get_bits_trace(s , n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
+#define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
-#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__)
+
+#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__)
#define tprintf(p, ...) av_log(p, AV_LOG_DEBUG, __VA_ARGS__)
#else //TRACE
-#define tprintf(p, ...) {}
+#define tprintf(p, ...) { }
#endif
#endif /* AVCODEC_GET_BITS_H */
projects / ffmpeg / blobdiff