From: Anton Khirnov <anton@khirnov.net>
To: ffmpeg-devel@ffmpeg.org
Subject: [FFmpeg-devel] [PATCH v4 2/4] lavc/bitstream: templatize for BE/LE
Date: Sat, 22 Oct 2022 12:32:55 +0200
Message-ID: <20221022103257.15463-2-anton@khirnov.net> (raw)
In-Reply-To: <20221022103257.15463-1-anton@khirnov.net>
Allows using both BE and LE bitstream readers in the same file.
---
libavcodec/Makefile | 1 +
libavcodec/bitstream.h | 563 ++++--------------
.../{bitstream.h => bitstream_template.h} | 243 ++++----
tests/ref/fate/source | 1 +
4 files changed, 220 insertions(+), 588 deletions(-)
copy libavcodec/{bitstream.h => bitstream_template.h} (54%)
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 8fa83c72b2..b77fe0db8e 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1238,6 +1238,7 @@ SKIPHEADERS += %_tablegen.h \
aaccoder_trellis.h \
aacenc_quantization.h \
aacenc_quantization_misc.h \
+ bitstream_template.h \
$(ARCH)/vpx_arith.h \
SKIPHEADERS-$(CONFIG_AMF) += amfenc.h
diff --git a/libavcodec/bitstream.h b/libavcodec/bitstream.h
index 6fd321dba5..ef7d8d55c2 100644
--- a/libavcodec/bitstream.h
+++ b/libavcodec/bitstream.h
@@ -23,6 +23,21 @@
* bitstream reader API header.
*/
+/*
+ * Bit order (endianness) is controlled by #defining BITSTREAM_BE and/or
+ * BITSTREAM_LE before #including this header. The corresponding bitreading
+ * functions are provided as bits_*_be()/bits_*_le() respectively.
+ *
+ * If neither or only BITSTREAM_BE is defined, then the default (unsuffixed)
+ * bits_*() will resolve to the big-endian implementation. If only BITSTREAM_LE
+ * is defined, little-endian will be the default.
+ *
+ * If both are defined, then the default can be controlled by defining at most
+ * one of BITSTREAM_DEFAULT_LE/BE. When BITSTREAM_DEFAULT_* is not defined, no
+ * default is provided and you must always explicitly use the _be() or _le()
+ * variants.
+ */
+
#ifndef AVCODEC_BITSTREAM_H
#define AVCODEC_BITSTREAM_H
@@ -42,461 +57,80 @@
#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
#endif
-typedef struct BitstreamContext {
- uint64_t bits; // stores bits read from the buffer
- const uint8_t *buffer, *buffer_end;
- const uint8_t *ptr; // pointer to the position inside a buffer
- unsigned bits_valid; // number of bits left in bits field
- unsigned size_in_bits;
-} BitstreamContext;
-
-/**
- * @return
- * - 0 on successful refill
- * - a negative number when bitstream end is hit
- *
- * Always succeeds when UNCHECKED_BITSTREAM_READER is enabled.
- */
-static inline int bits_priv_refill_64(BitstreamContext *bc)
-{
-#if !UNCHECKED_BITSTREAM_READER
- if (bc->ptr >= bc->buffer_end)
- return -1;
-#endif
-
-#ifdef BITSTREAM_READER_LE
- bc->bits = AV_RL64(bc->ptr);
-#else
- bc->bits = AV_RB64(bc->ptr);
-#endif
- bc->ptr += 8;
- bc->bits_valid = 64;
-
- return 0;
-}
-
-/**
- * @return
- * - 0 on successful refill
- * - a negative number when bitstream end is hit
- *
- * Always succeeds when UNCHECKED_BITSTREAM_READER is enabled.
- */
-static inline int bits_priv_refill_32(BitstreamContext *bc)
-{
-#if !UNCHECKED_BITSTREAM_READER
- if (bc->ptr >= bc->buffer_end)
- return -1;
-#endif
-
-#ifdef BITSTREAM_READER_LE
- bc->bits |= (uint64_t)AV_RL32(bc->ptr) << bc->bits_valid;
-#else
- bc->bits |= (uint64_t)AV_RB32(bc->ptr) << (32 - bc->bits_valid);
-#endif
- bc->ptr += 4;
- bc->bits_valid += 32;
-
- return 0;
-}
-
-/**
- * Initialize BitstreamContext.
- * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
- * larger than the actual read bits because some optimized bitstream
- * readers read 32 or 64 bits 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 int bits_init(BitstreamContext *bc, const uint8_t *buffer,
- unsigned int bit_size)
-{
- unsigned int buffer_size;
-
- if (bit_size > INT_MAX - 7 || !buffer) {
- bc->buffer = NULL;
- bc->ptr = NULL;
- bc->bits_valid = 0;
- return AVERROR_INVALIDDATA;
- }
-
- buffer_size = (bit_size + 7) >> 3;
-
- bc->buffer = buffer;
- bc->buffer_end = buffer + buffer_size;
- bc->ptr = bc->buffer;
- bc->size_in_bits = bit_size;
- bc->bits_valid = 0;
- bc->bits = 0;
-
- bits_priv_refill_64(bc);
-
- return 0;
-}
-
-/**
- * Initialize BitstreamContext.
- * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
- * larger than the actual read bits because some optimized bitstream
- * readers read 32 or 64 bits 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 bits_init8(BitstreamContext *bc, const uint8_t *buffer,
- unsigned int byte_size)
-{
- if (byte_size > INT_MAX / 8)
- return AVERROR_INVALIDDATA;
- return bits_init(bc, buffer, byte_size * 8);
-}
-
-/**
- * Return number of bits already read.
- */
-static inline int bits_tell(const BitstreamContext *bc)
-{
- return (bc->ptr - bc->buffer) * 8 - bc->bits_valid;
-}
-
-/**
- * Return buffer size in bits.
- */
-static inline int bits_size(const BitstreamContext *bc)
-{
- return bc->size_in_bits;
-}
-
-/**
- * Return the number of the bits left in a buffer.
- */
-static inline int bits_left(const BitstreamContext *bc)
-{
- return (bc->buffer - bc->ptr) * 8 + bc->size_in_bits + bc->bits_valid;
-}
-
-static inline uint64_t bits_priv_val_show(BitstreamContext *bc, unsigned int n)
-{
- av_assert2(n > 0 && n <= 64);
-
-#ifdef BITSTREAM_READER_LE
- return bc->bits & (UINT64_MAX >> (64 - n));
-#else
- return bc->bits >> (64 - n);
-#endif
-}
-
-static inline void bits_priv_skip_remaining(BitstreamContext *bc, unsigned int n)
-{
-#ifdef BITSTREAM_READER_LE
- bc->bits >>= n;
-#else
- bc->bits <<= n;
-#endif
- bc->bits_valid -= n;
-}
-
-static inline uint64_t bits_priv_val_get(BitstreamContext *bc, unsigned int n)
-{
- uint64_t ret;
-
- av_assert2(n > 0 && n < 64);
-
- ret = bits_priv_val_show(bc, n);
- bits_priv_skip_remaining(bc, n);
-
- return ret;
-}
-
-/**
- * Return one bit from the buffer.
- */
-static inline unsigned int bits_read_bit(BitstreamContext *bc)
-{
- if (!bc->bits_valid && bits_priv_refill_64(bc) < 0)
- return 0;
-
- return bits_priv_val_get(bc, 1);
-}
-
-/**
- * Return n bits from the buffer, n has to be in the 1-32 range.
- * May be faster than bits_read() when n is not a compile-time constant and is
- * known to be non-zero;
- */
-static inline uint32_t bits_read_nz(BitstreamContext *bc, unsigned int n)
-{
- av_assert2(n > 0 && n <= 32);
-
- if (n > bc->bits_valid) {
- if (bits_priv_refill_32(bc) < 0)
- bc->bits_valid = n;
- }
-
- return bits_priv_val_get(bc, n);
-}
-
-/**
- * Return n bits from the buffer, n has to be in the 0-32 range.
- */
-static inline uint32_t bits_read(BitstreamContext *bc, unsigned int n)
-{
- av_assert2(n <= 32);
-
- if (!n)
- return 0;
-
- return bits_read_nz(bc, n);
-}
-
-/**
- * Return n bits from the buffer, n has to be in the 0-63 range.
- */
-static inline uint64_t bits_read_63(BitstreamContext *bc, unsigned int n)
-{
- uint64_t ret = 0;
- unsigned left = 0;
-
- av_assert2(n <= 63);
-
- if (!n)
- return 0;
-
- if (n > bc->bits_valid) {
- left = bc->bits_valid;
- n -= left;
-
- if (left)
- ret = bits_priv_val_get(bc, left);
-
- if (bits_priv_refill_64(bc) < 0)
- bc->bits_valid = n;
-
- }
-
-#ifdef BITSTREAM_READER_LE
- ret = bits_priv_val_get(bc, n) << left | ret;
-#else
- ret = bits_priv_val_get(bc, n) | ret << n;
+// select the default endianness, if any
+#if defined(BITSTREAM_LE) && defined(BITSTREAM_BE)
+
+# if defined(BITSTREAM_DEFAULT_BE) && defined(BITSTREAM_DEFAULT_LE)
+# error "At most one of BITSTREAM_DEFAULT_BE/LE must be defined"
+# elif defined(BITSTREAM_DEFAULT_BE)
+# define BITS_DEFAULT_BE
+# elif defined(BITSTREAM_DEFAULT_LE)
+# define BITS_DEFAULT_LE
+# endif
+
+#elif defined(BITSTREAM_LE)
+# define BITS_DEFAULT_LE
+#else // select BE if nothing is requested explicitly
+# define BITS_DEFAULT_BE
+# define BITSTREAM_WANT_BE
#endif
- return ret;
-}
+#if defined(BITS_DEFAULT_LE)
+
+# define BitstreamContext BitstreamContextLE
+# define bits_init bits_init_le
+# define bits_init8 bits_init8_le
+# define bits_tell bits_tell_le
+# define bits_size bits_size_le
+# define bits_left bits_left_le
+# define bits_read_bit bits_read_bit_le
+# define bits_read_nz bits_read_nz_le
+# define bits_read bits_read_le
+# define bits_read_63 bits_read_63_le
+# define bits_read_64 bits_read_64_le
+# define bits_read_signed bits_read_signed_le
+# define bits_peek_nz bits_peek_nz_le
+# define bits_peek bits_peek_le
+# define bits_peek_signed bits_peek_signed_le
+# define bits_skip bits_skip_le
+# define bits_seek bits_seek_le
+# define bits_align bits_align_le
+# define bits_read_xbits bits_read_xbits_le
+# define bits_decode012 bits_decode012_le
+# define bits_decode210 bits_decode210_le
+# define bits_apply_sign bits_apply_sign_le
+# define bits_read_vlc bits_read_vlc_le
+
+#elif defined(BITS_DEFAULT_BE)
+
+# define BitstreamContext BitstreamContextBE
+# define bits_init bits_init_be
+# define bits_init8 bits_init8_be
+# define bits_tell bits_tell_be
+# define bits_size bits_size_be
+# define bits_left bits_left_be
+# define bits_read_bit bits_read_bit_be
+# define bits_read_nz bits_read_nz_be
+# define bits_read bits_read_be
+# define bits_read_63 bits_read_63_be
+# define bits_read_64 bits_read_64_be
+# define bits_read_signed bits_read_signed_be
+# define bits_peek_nz bits_peek_nz_be
+# define bits_peek bits_peek_be
+# define bits_peek_signed bits_peek_signed_be
+# define bits_skip bits_skip_be
+# define bits_seek bits_seek_be
+# define bits_align bits_align_be
+# define bits_read_xbits bits_read_xbits_be
+# define bits_decode012 bits_decode012_be
+# define bits_decode210 bits_decode210_be
+# define bits_apply_sign bits_apply_sign_be
+# define bits_read_vlc bits_read_vlc_be
-/**
- * Return n bits from the buffer, n has to be in the 0-64 range.
- */
-static inline uint64_t bits_read_64(BitstreamContext *bc, unsigned int n)
-{
- av_assert2(n <= 64);
-
- if (n == 64) {
- uint64_t ret = bits_read_63(bc, 63);
-#ifdef BITSTREAM_READER_LE
- return ret | ((uint64_t)bits_read_bit(bc) << 63);
-#else
- return (ret << 1) | (uint64_t)bits_read_bit(bc);
#endif
- }
- return bits_read_63(bc, n);
-}
-
-/**
- * Return n bits from the buffer as a signed integer.
- * n has to be in the 0-32 range.
- */
-static inline int32_t bits_read_signed(BitstreamContext *bc, unsigned int n)
-{
- return sign_extend(bits_read(bc, n), n);
-}
-
-/**
- * Return n bits from the buffer but do not change the buffer state.
- * n has to be in the 1-32 range. May
- */
-static inline uint32_t bits_peek_nz(BitstreamContext *bc, unsigned int n)
-{
- av_assert2(n > 0 && n <= 32);
-
- if (n > bc->bits_valid)
- bits_priv_refill_32(bc);
-
- return bits_priv_val_show(bc, n);
-}
-
-/**
- * Return n bits from the buffer but do not change the buffer state.
- * n has to be in the 0-32 range.
- */
-static inline uint32_t bits_peek(BitstreamContext *bc, unsigned int n)
-{
- av_assert2(n <= 32);
-
- if (!n)
- return 0;
- return bits_peek_nz(bc, n);
-}
-
-/**
- * Return n bits from the buffer as a signed integer,
- * do not change the buffer state.
- * n has to be in the 0-32 range.
- */
-static inline int bits_peek_signed(BitstreamContext *bc, unsigned int n)
-{
- return sign_extend(bits_peek(bc, n), n);
-}
-
-/**
- * Skip n bits in the buffer.
- */
-static inline void bits_skip(BitstreamContext *bc, unsigned int n)
-{
- if (n < bc->bits_valid)
- bits_priv_skip_remaining(bc, n);
- else {
- n -= bc->bits_valid;
- bc->bits = 0;
- bc->bits_valid = 0;
-
- if (n >= 64) {
- unsigned int skip = n / 8;
-
- n -= skip * 8;
- bc->ptr += skip;
- }
- bits_priv_refill_64(bc);
- if (n)
- bits_priv_skip_remaining(bc, n);
- }
-}
-
-/**
- * Seek to the given bit position.
- */
-static inline void bits_seek(BitstreamContext *bc, unsigned pos)
-{
- bc->ptr = bc->buffer;
- bc->bits = 0;
- bc->bits_valid = 0;
-
- bits_skip(bc, pos);
-}
-
-/**
- * Skip bits to a byte boundary.
- */
-static inline const uint8_t *bits_align(BitstreamContext *bc)
-{
- unsigned int n = -bits_tell(bc) & 7;
- if (n)
- bits_skip(bc, n);
- return bc->buffer + (bits_tell(bc) >> 3);
-}
-
-/**
- * Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
- * If MSB not set it is negative.
- * @param n length in bits
- */
-static inline int bits_read_xbits(BitstreamContext *bc, unsigned int n)
-{
- int32_t cache = bits_peek(bc, 32);
- int sign = ~cache >> 31;
- bits_priv_skip_remaining(bc, n);
-
- return ((((uint32_t)(sign ^ cache)) >> (32 - n)) ^ sign) - sign;
-}
-
-/**
- * Return decoded truncated unary code for the values 0, 1, 2.
- */
-static inline int bits_decode012(BitstreamContext *bc)
-{
- if (!bits_read_bit(bc))
- return 0;
- else
- return bits_read_bit(bc) + 1;
-}
-
-/**
- * Return decoded truncated unary code for the values 2, 1, 0.
- */
-static inline int bits_decode210(BitstreamContext *bc)
-{
- if (bits_read_bit(bc))
- return 0;
- else
- return 2 - bits_read_bit(bc);
-}
-
-/* Read sign bit and flip the sign of the provided value accordingly. */
-static inline int bits_apply_sign(BitstreamContext *bc, int val)
-{
- int sign = bits_read_signed(bc, 1);
- return (val ^ sign) - sign;
-}
-
-static inline int bits_skip_1stop_8data(BitstreamContext *s)
-{
- if (bits_left(s) <= 0)
- return AVERROR_INVALIDDATA;
-
- while (bits_read_bit(s)) {
- bits_skip(s, 8);
- if (bits_left(s) <= 0)
- return AVERROR_INVALIDDATA;
- }
-
- return 0;
-}
-
-/**
- * Return the LUT element for the given bitstream configuration.
- */
-static inline int bits_priv_set_idx(BitstreamContext *bc, int code, int *n, int *nb_bits,
- const VLCElem *table)
-{
- unsigned idx;
-
- *nb_bits = -*n;
- idx = bits_peek(bc, *nb_bits) + code;
- *n = table[idx].len;
-
- return table[idx].sym;
-}
-
-/**
- * Parse a vlc code.
- * @param bits is the number of bits which will be read at once, must be
- * identical to nb_bits in init_vlc()
- * @param max_depth is the number of times bits bits must be read to completely
- * read the longest vlc code
- * = (max_vlc_length + bits - 1) / bits
- * If the vlc code is invalid and max_depth=1, then no bits will be removed.
- * If the vlc code is invalid and max_depth>1, then the number of bits removed
- * is undefined.
- */
-static inline int bits_read_vlc(BitstreamContext *bc, const VLCElem *table,
- int bits, int max_depth)
-{
- int nb_bits;
- unsigned idx = bits_peek(bc, bits);
- int code = table[idx].sym;
- int n = table[idx].len;
-
- if (max_depth > 1 && n < 0) {
- bits_priv_skip_remaining(bc, bits);
- code = bits_priv_set_idx(bc, code, &n, &nb_bits, table);
- if (max_depth > 2 && n < 0) {
- bits_priv_skip_remaining(bc, nb_bits);
- code = bits_priv_set_idx(bc, code, &n, &nb_bits, table);
- }
- }
- bits_priv_skip_remaining(bc, n);
-
- return code;
-}
+#undef BITS_DEFAULT_LE
+#undef BITS_DEFAULT_BE
#define BITS_RL_VLC(level, run, bc, table, bits, max_depth) \
do { \
@@ -527,3 +161,32 @@ static inline int bits_read_vlc(BitstreamContext *bc, const VLCElem *table,
} while (0)
#endif /* AVCODEC_BITSTREAM_H */
+
+// the following is deliberately outside of the standard #include guards
+
+#if defined(BITSTREAM_LE) && !defined(BITSTREAM_WANT_LE)
+# define BITSTREAM_WANT_LE
+#endif
+
+#if defined(BITSTREAM_BE) && !defined(BITSTREAM_WANT_BE)
+# define BITSTREAM_WANT_BE
+#endif
+
+#if defined(BITSTREAM_WANT_LE) && !defined(AVCODEC_BITSTREAM_LE)
+#define AVCODEC_BITSTREAM_LE
+
+#define BITSTREAM_TEMPLATE_LE
+#include "bitstream_template.h"
+#undef BITSTREAM_TEMPLATE_LE
+
+#endif
+
+#if defined(BITSTREAM_WANT_BE) && !defined(AVCODEC_BITSTREAM_BE)
+#define AVCODEC_BITSTREAM_BE
+
+#include "bitstream_template.h"
+
+#endif
+
+#undef BITSTREAM_WANT_LE
+#undef BITSTREAM_WANT_BE
diff --git a/libavcodec/bitstream.h b/libavcodec/bitstream_template.h
similarity index 54%
copy from libavcodec/bitstream.h
copy to libavcodec/bitstream_template.h
index 6fd321dba5..f2c14fc4d3 100644
--- a/libavcodec/bitstream.h
+++ b/libavcodec/bitstream_template.h
@@ -18,37 +18,27 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-/**
- * @file
- * bitstream reader API header.
- */
-
-#ifndef AVCODEC_BITSTREAM_H
-#define AVCODEC_BITSTREAM_H
-
-#include <stdint.h>
-
-#include "config.h"
-
-#include "libavutil/avassert.h"
-#include "libavutil/common.h"
-#include "libavutil/intreadwrite.h"
-#include "libavutil/log.h"
+#ifdef BITSTREAM_TEMPLATE_LE
+# define BS_SUFFIX_LOWER _le
+# define BS_SUFFIX_UPPER LE
+#else
+# define BS_SUFFIX_LOWER _be
+# define BS_SUFFIX_UPPER BE
+#endif
-#include "mathops.h"
-#include "vlc.h"
+#define BS_JOIN(x, y, z) x ## y ## z
+#define BS_JOIN3(x, y, z) BS_JOIN(x, y, z)
+#define BS_FUNC(x) BS_JOIN3(bits_, x, BS_SUFFIX_LOWER)
-#ifndef UNCHECKED_BITSTREAM_READER
-#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
-#endif
+#define BSCTX BS_JOIN3(Bitstream, Context, BS_SUFFIX_UPPER)
-typedef struct BitstreamContext {
+typedef struct BSCTX {
uint64_t bits; // stores bits read from the buffer
const uint8_t *buffer, *buffer_end;
const uint8_t *ptr; // pointer to the position inside a buffer
unsigned bits_valid; // number of bits left in bits field
unsigned size_in_bits;
-} BitstreamContext;
+} BSCTX;
/**
* @return
@@ -57,14 +47,14 @@ typedef struct BitstreamContext {
*
* Always succeeds when UNCHECKED_BITSTREAM_READER is enabled.
*/
-static inline int bits_priv_refill_64(BitstreamContext *bc)
+static inline int BS_FUNC(priv_refill_64)(BSCTX *bc)
{
#if !UNCHECKED_BITSTREAM_READER
if (bc->ptr >= bc->buffer_end)
return -1;
#endif
-#ifdef BITSTREAM_READER_LE
+#ifdef BITSTREAM_TEMPLATE_LE
bc->bits = AV_RL64(bc->ptr);
#else
bc->bits = AV_RB64(bc->ptr);
@@ -82,14 +72,14 @@ static inline int bits_priv_refill_64(BitstreamContext *bc)
*
* Always succeeds when UNCHECKED_BITSTREAM_READER is enabled.
*/
-static inline int bits_priv_refill_32(BitstreamContext *bc)
+static inline int BS_FUNC(priv_refill_32)(BSCTX *bc)
{
#if !UNCHECKED_BITSTREAM_READER
if (bc->ptr >= bc->buffer_end)
return -1;
#endif
-#ifdef BITSTREAM_READER_LE
+#ifdef BITSTREAM_TEMPLATE_LE
bc->bits |= (uint64_t)AV_RL32(bc->ptr) << bc->bits_valid;
#else
bc->bits |= (uint64_t)AV_RB32(bc->ptr) << (32 - bc->bits_valid);
@@ -108,8 +98,8 @@ static inline int bits_priv_refill_32(BitstreamContext *bc)
* @param bit_size the size of the buffer in bits
* @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
*/
-static inline int bits_init(BitstreamContext *bc, const uint8_t *buffer,
- unsigned int bit_size)
+static inline int BS_FUNC(init)(BSCTX *bc, const uint8_t *buffer,
+ unsigned int bit_size)
{
unsigned int buffer_size;
@@ -129,7 +119,7 @@ static inline int bits_init(BitstreamContext *bc, const uint8_t *buffer,
bc->bits_valid = 0;
bc->bits = 0;
- bits_priv_refill_64(bc);
+ BS_FUNC(priv_refill_64)(bc);
return 0;
}
@@ -142,18 +132,18 @@ static inline int bits_init(BitstreamContext *bc, const uint8_t *buffer,
* @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 bits_init8(BitstreamContext *bc, const uint8_t *buffer,
- unsigned int byte_size)
+static inline int BS_FUNC(init8)(BSCTX *bc, const uint8_t *buffer,
+ unsigned int byte_size)
{
if (byte_size > INT_MAX / 8)
return AVERROR_INVALIDDATA;
- return bits_init(bc, buffer, byte_size * 8);
+ return BS_FUNC(init)(bc, buffer, byte_size * 8);
}
/**
* Return number of bits already read.
*/
-static inline int bits_tell(const BitstreamContext *bc)
+static inline int BS_FUNC(tell)(const BSCTX *bc)
{
return (bc->ptr - bc->buffer) * 8 - bc->bits_valid;
}
@@ -161,7 +151,7 @@ static inline int bits_tell(const BitstreamContext *bc)
/**
* Return buffer size in bits.
*/
-static inline int bits_size(const BitstreamContext *bc)
+static inline int BS_FUNC(size)(const BSCTX *bc)
{
return bc->size_in_bits;
}
@@ -169,25 +159,25 @@ static inline int bits_size(const BitstreamContext *bc)
/**
* Return the number of the bits left in a buffer.
*/
-static inline int bits_left(const BitstreamContext *bc)
+static inline int BS_FUNC(left)(const BSCTX *bc)
{
return (bc->buffer - bc->ptr) * 8 + bc->size_in_bits + bc->bits_valid;
}
-static inline uint64_t bits_priv_val_show(BitstreamContext *bc, unsigned int n)
+static inline uint64_t BS_FUNC(priv_val_show)(BSCTX *bc, unsigned int n)
{
av_assert2(n > 0 && n <= 64);
-#ifdef BITSTREAM_READER_LE
+#ifdef BITSTREAM_TEMPLATE_LE
return bc->bits & (UINT64_MAX >> (64 - n));
#else
return bc->bits >> (64 - n);
#endif
}
-static inline void bits_priv_skip_remaining(BitstreamContext *bc, unsigned int n)
+static inline void BS_FUNC(priv_skip_remaining)(BSCTX *bc, unsigned int n)
{
-#ifdef BITSTREAM_READER_LE
+#ifdef BITSTREAM_TEMPLATE_LE
bc->bits >>= n;
#else
bc->bits <<= n;
@@ -195,14 +185,14 @@ static inline void bits_priv_skip_remaining(BitstreamContext *bc, unsigned int n
bc->bits_valid -= n;
}
-static inline uint64_t bits_priv_val_get(BitstreamContext *bc, unsigned int n)
+static inline uint64_t BS_FUNC(priv_val_get)(BSCTX *bc, unsigned int n)
{
uint64_t ret;
av_assert2(n > 0 && n < 64);
- ret = bits_priv_val_show(bc, n);
- bits_priv_skip_remaining(bc, n);
+ ret = BS_FUNC(priv_val_show)(bc, n);
+ BS_FUNC(priv_skip_remaining)(bc, n);
return ret;
}
@@ -210,12 +200,12 @@ static inline uint64_t bits_priv_val_get(BitstreamContext *bc, unsigned int n)
/**
* Return one bit from the buffer.
*/
-static inline unsigned int bits_read_bit(BitstreamContext *bc)
+static inline unsigned int BS_FUNC(read_bit)(BSCTX *bc)
{
- if (!bc->bits_valid && bits_priv_refill_64(bc) < 0)
+ if (!bc->bits_valid && BS_FUNC(priv_refill_64)(bc) < 0)
return 0;
- return bits_priv_val_get(bc, 1);
+ return BS_FUNC(priv_val_get)(bc, 1);
}
/**
@@ -223,35 +213,35 @@ static inline unsigned int bits_read_bit(BitstreamContext *bc)
* May be faster than bits_read() when n is not a compile-time constant and is
* known to be non-zero;
*/
-static inline uint32_t bits_read_nz(BitstreamContext *bc, unsigned int n)
+static inline uint32_t BS_FUNC(read_nz)(BSCTX *bc, unsigned int n)
{
av_assert2(n > 0 && n <= 32);
if (n > bc->bits_valid) {
- if (bits_priv_refill_32(bc) < 0)
+ if (BS_FUNC(priv_refill_32)(bc) < 0)
bc->bits_valid = n;
}
- return bits_priv_val_get(bc, n);
+ return BS_FUNC(priv_val_get)(bc, n);
}
/**
* Return n bits from the buffer, n has to be in the 0-32 range.
*/
-static inline uint32_t bits_read(BitstreamContext *bc, unsigned int n)
+static inline uint32_t BS_FUNC(read)(BSCTX *bc, unsigned int n)
{
av_assert2(n <= 32);
if (!n)
return 0;
- return bits_read_nz(bc, n);
+ return BS_FUNC(read_nz)(bc, n);
}
/**
* Return n bits from the buffer, n has to be in the 0-63 range.
*/
-static inline uint64_t bits_read_63(BitstreamContext *bc, unsigned int n)
+static inline uint64_t BS_FUNC(read_63)(BSCTX *bc, unsigned int n)
{
uint64_t ret = 0;
unsigned left = 0;
@@ -266,17 +256,17 @@ static inline uint64_t bits_read_63(BitstreamContext *bc, unsigned int n)
n -= left;
if (left)
- ret = bits_priv_val_get(bc, left);
+ ret = BS_FUNC(priv_val_get)(bc, left);
- if (bits_priv_refill_64(bc) < 0)
+ if (BS_FUNC(priv_refill_64)(bc) < 0)
bc->bits_valid = n;
}
-#ifdef BITSTREAM_READER_LE
- ret = bits_priv_val_get(bc, n) << left | ret;
+#ifdef BITSTREAM_TEMPLATE_LE
+ ret = BS_FUNC(priv_val_get)(bc, n) << left | ret;
#else
- ret = bits_priv_val_get(bc, n) | ret << n;
+ ret = BS_FUNC(priv_val_get)(bc, n) | ret << n;
#endif
return ret;
@@ -285,56 +275,56 @@ static inline uint64_t bits_read_63(BitstreamContext *bc, unsigned int n)
/**
* Return n bits from the buffer, n has to be in the 0-64 range.
*/
-static inline uint64_t bits_read_64(BitstreamContext *bc, unsigned int n)
+static inline uint64_t BS_FUNC(read_64)(BSCTX *bc, unsigned int n)
{
av_assert2(n <= 64);
if (n == 64) {
- uint64_t ret = bits_read_63(bc, 63);
-#ifdef BITSTREAM_READER_LE
- return ret | ((uint64_t)bits_read_bit(bc) << 63);
+ uint64_t ret = BS_FUNC(read_63)(bc, 63);
+#ifdef BITSTREAM_TEMPLATE_LE
+ return ret | ((uint64_t)BS_FUNC(read_bit)(bc) << 63);
#else
- return (ret << 1) | (uint64_t)bits_read_bit(bc);
+ return (ret << 1) | (uint64_t)BS_FUNC(read_bit)(bc);
#endif
}
- return bits_read_63(bc, n);
+ return BS_FUNC(read_63)(bc, n);
}
/**
* Return n bits from the buffer as a signed integer.
* n has to be in the 0-32 range.
*/
-static inline int32_t bits_read_signed(BitstreamContext *bc, unsigned int n)
+static inline int32_t BS_FUNC(read_signed)(BSCTX *bc, unsigned int n)
{
- return sign_extend(bits_read(bc, n), n);
+ return sign_extend(BS_FUNC(read)(bc, n), n);
}
/**
* Return n bits from the buffer but do not change the buffer state.
* n has to be in the 1-32 range. May
*/
-static inline uint32_t bits_peek_nz(BitstreamContext *bc, unsigned int n)
+static inline uint32_t BS_FUNC(peek_nz)(BSCTX *bc, unsigned int n)
{
av_assert2(n > 0 && n <= 32);
if (n > bc->bits_valid)
- bits_priv_refill_32(bc);
+ BS_FUNC(priv_refill_32)(bc);
- return bits_priv_val_show(bc, n);
+ return BS_FUNC(priv_val_show)(bc, n);
}
/**
* Return n bits from the buffer but do not change the buffer state.
* n has to be in the 0-32 range.
*/
-static inline uint32_t bits_peek(BitstreamContext *bc, unsigned int n)
+static inline uint32_t BS_FUNC(peek)(BSCTX *bc, unsigned int n)
{
av_assert2(n <= 32);
if (!n)
return 0;
- return bits_peek_nz(bc, n);
+ return BS_FUNC(peek_nz)(bc, n);
}
/**
@@ -342,18 +332,18 @@ static inline uint32_t bits_peek(BitstreamContext *bc, unsigned int n)
* do not change the buffer state.
* n has to be in the 0-32 range.
*/
-static inline int bits_peek_signed(BitstreamContext *bc, unsigned int n)
+static inline int BS_FUNC(peek_signed)(BSCTX *bc, unsigned int n)
{
- return sign_extend(bits_peek(bc, n), n);
+ return sign_extend(BS_FUNC(peek)(bc, n), n);
}
/**
* Skip n bits in the buffer.
*/
-static inline void bits_skip(BitstreamContext *bc, unsigned int n)
+static inline void BS_FUNC(skip)(BSCTX *bc, unsigned int n)
{
if (n < bc->bits_valid)
- bits_priv_skip_remaining(bc, n);
+ BS_FUNC(priv_skip_remaining)(bc, n);
else {
n -= bc->bits_valid;
bc->bits = 0;
@@ -365,33 +355,33 @@ static inline void bits_skip(BitstreamContext *bc, unsigned int n)
n -= skip * 8;
bc->ptr += skip;
}
- bits_priv_refill_64(bc);
+ BS_FUNC(priv_refill_64)(bc);
if (n)
- bits_priv_skip_remaining(bc, n);
+ BS_FUNC(priv_skip_remaining)(bc, n);
}
}
/**
* Seek to the given bit position.
*/
-static inline void bits_seek(BitstreamContext *bc, unsigned pos)
+static inline void BS_FUNC(seek)(BSCTX *bc, unsigned pos)
{
bc->ptr = bc->buffer;
bc->bits = 0;
bc->bits_valid = 0;
- bits_skip(bc, pos);
+ BS_FUNC(skip)(bc, pos);
}
/**
* Skip bits to a byte boundary.
*/
-static inline const uint8_t *bits_align(BitstreamContext *bc)
+static inline const uint8_t *BS_FUNC(align)(BSCTX *bc)
{
- unsigned int n = -bits_tell(bc) & 7;
+ unsigned int n = -BS_FUNC(tell)(bc) & 7;
if (n)
- bits_skip(bc, n);
- return bc->buffer + (bits_tell(bc) >> 3);
+ BS_FUNC(skip)(bc, n);
+ return bc->buffer + (BS_FUNC(tell)(bc) >> 3);
}
/**
@@ -399,11 +389,11 @@ static inline const uint8_t *bits_align(BitstreamContext *bc)
* If MSB not set it is negative.
* @param n length in bits
*/
-static inline int bits_read_xbits(BitstreamContext *bc, unsigned int n)
+static inline int BS_FUNC(read_xbits)(BSCTX *bc, unsigned int n)
{
- int32_t cache = bits_peek(bc, 32);
+ int32_t cache = BS_FUNC(peek)(bc, 32);
int sign = ~cache >> 31;
- bits_priv_skip_remaining(bc, n);
+ BS_FUNC(priv_skip_remaining)(bc, n);
return ((((uint32_t)(sign ^ cache)) >> (32 - n)) ^ sign) - sign;
}
@@ -411,40 +401,40 @@ static inline int bits_read_xbits(BitstreamContext *bc, unsigned int n)
/**
* Return decoded truncated unary code for the values 0, 1, 2.
*/
-static inline int bits_decode012(BitstreamContext *bc)
+static inline int BS_FUNC(decode012)(BSCTX *bc)
{
- if (!bits_read_bit(bc))
+ if (!BS_FUNC(read_bit)(bc))
return 0;
else
- return bits_read_bit(bc) + 1;
+ return BS_FUNC(read_bit)(bc) + 1;
}
/**
* Return decoded truncated unary code for the values 2, 1, 0.
*/
-static inline int bits_decode210(BitstreamContext *bc)
+static inline int BS_FUNC(decode210)(BSCTX *bc)
{
- if (bits_read_bit(bc))
+ if (BS_FUNC(read_bit)(bc))
return 0;
else
- return 2 - bits_read_bit(bc);
+ return 2 - BS_FUNC(read_bit)(bc);
}
/* Read sign bit and flip the sign of the provided value accordingly. */
-static inline int bits_apply_sign(BitstreamContext *bc, int val)
+static inline int BS_FUNC(apply_sign)(BSCTX *bc, int val)
{
- int sign = bits_read_signed(bc, 1);
+ int sign = BS_FUNC(read_signed)(bc, 1);
return (val ^ sign) - sign;
}
-static inline int bits_skip_1stop_8data(BitstreamContext *s)
+static inline int BS_FUNC(skip_1stop_8data)(BSCTX *s)
{
- if (bits_left(s) <= 0)
+ if (BS_FUNC(left)(s) <= 0)
return AVERROR_INVALIDDATA;
- while (bits_read_bit(s)) {
- bits_skip(s, 8);
- if (bits_left(s) <= 0)
+ while (BS_FUNC(read_bit)(s)) {
+ BS_FUNC(skip)(s, 8);
+ if (BS_FUNC(left)(s) <= 0)
return AVERROR_INVALIDDATA;
}
@@ -454,13 +444,13 @@ static inline int bits_skip_1stop_8data(BitstreamContext *s)
/**
* Return the LUT element for the given bitstream configuration.
*/
-static inline int bits_priv_set_idx(BitstreamContext *bc, int code, int *n, int *nb_bits,
- const VLCElem *table)
+static inline int BS_FUNC(priv_set_idx)(BSCTX *bc, int code, int *n,
+ int *nb_bits, const VLCElem *table)
{
unsigned idx;
*nb_bits = -*n;
- idx = bits_peek(bc, *nb_bits) + code;
+ idx = BS_FUNC(peek)(bc, *nb_bits) + code;
*n = table[idx].len;
return table[idx].sym;
@@ -477,53 +467,30 @@ static inline int bits_priv_set_idx(BitstreamContext *bc, int code, int *n, int
* If the vlc code is invalid and max_depth>1, then the number of bits removed
* is undefined.
*/
-static inline int bits_read_vlc(BitstreamContext *bc, const VLCElem *table,
- int bits, int max_depth)
+static inline int BS_FUNC(read_vlc)(BSCTX *bc, const VLCElem *table,
+ int bits, int max_depth)
{
int nb_bits;
- unsigned idx = bits_peek(bc, bits);
+ unsigned idx = BS_FUNC(peek)(bc, bits);
int code = table[idx].sym;
int n = table[idx].len;
if (max_depth > 1 && n < 0) {
- bits_priv_skip_remaining(bc, bits);
- code = bits_priv_set_idx(bc, code, &n, &nb_bits, table);
+ BS_FUNC(priv_skip_remaining)(bc, bits);
+ code = BS_FUNC(priv_set_idx)(bc, code, &n, &nb_bits, table);
if (max_depth > 2 && n < 0) {
- bits_priv_skip_remaining(bc, nb_bits);
- code = bits_priv_set_idx(bc, code, &n, &nb_bits, table);
+ BS_FUNC(priv_skip_remaining)(bc, nb_bits);
+ code = BS_FUNC(priv_set_idx)(bc, code, &n, &nb_bits, table);
}
}
- bits_priv_skip_remaining(bc, n);
+ BS_FUNC(priv_skip_remaining)(bc, n);
return code;
}
-#define BITS_RL_VLC(level, run, bc, table, bits, max_depth) \
- do { \
- int n, nb_bits; \
- unsigned int index = bits_peek(bc, bits); \
- level = table[index].level; \
- n = table[index].len; \
- \
- if (max_depth > 1 && n < 0) { \
- bits_skip(bc, bits); \
- \
- nb_bits = -n; \
- \
- index = bits_peek(bc, nb_bits) + level; \
- level = table[index].level; \
- n = table[index].len; \
- if (max_depth > 2 && n < 0) { \
- bits_skip(bc, nb_bits); \
- nb_bits = -n; \
- \
- index = bits_peek(bc, nb_bits) + level; \
- level = table[index].level; \
- n = table[index].len; \
- } \
- } \
- run = table[index].run; \
- bits_skip(bc, n); \
- } while (0)
-
-#endif /* AVCODEC_BITSTREAM_H */
+#undef BSCTX
+#undef BS_FUNC
+#undef BS_JOIN3
+#undef BS_JOIN
+#undef BS_SUFFIX_UPPER
+#undef BS_SUFFIX_LOWER
diff --git a/tests/ref/fate/source b/tests/ref/fate/source
index 16ea7ef9c1..3b7ea9c379 100644
--- a/tests/ref/fate/source
+++ b/tests/ref/fate/source
@@ -21,6 +21,7 @@ Headers without standard inclusion guards:
compat/djgpp/math.h
compat/float/float.h
compat/float/limits.h
+libavcodec/bitstream_template.h
tools/decode_simple.h
Use of av_clip() where av_clip_uintp2() could be used:
Use of av_clip() where av_clip_intp2() could be used:
--
2.35.1
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
next prev parent reply other threads:[~2022-10-22 10:34 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-22 10:32 [FFmpeg-devel] [PATCH v4 1/4] lavc: add standalone cached bitstream reader Anton Khirnov
2022-10-22 10:32 ` Anton Khirnov [this message]
2022-10-22 10:32 ` [FFmpeg-devel] [PATCH v4 3/4] lavc/tests: add a cached bitstream reader test Anton Khirnov
2022-10-22 10:32 ` [FFmpeg-devel] [PATCH v4 4/4] lavc/get_bits: add a compat wrapper for the cached bitstream reader Anton Khirnov
2022-10-22 10:37 ` [FFmpeg-devel] [PATCH v4 1/4] lavc: add standalone " Paul B Mahol
2023-01-03 11:19 ` Anton Khirnov
2023-01-06 10:09 ` Anton Khirnov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20221022103257.15463-2-anton@khirnov.net \
--to=anton@khirnov.net \
--cc=ffmpeg-devel@ffmpeg.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Git Inbox Mirror of the ffmpeg-devel mailing list - see https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
This inbox may be cloned and mirrored by anyone:
git clone --mirror https://master.gitmailbox.com/ffmpegdev/0 ffmpegdev/git/0.git
# If you have public-inbox 1.1+ installed, you may
# initialize and index your mirror using the following commands:
public-inbox-init -V2 ffmpegdev ffmpegdev/ https://master.gitmailbox.com/ffmpegdev \
ffmpegdev@gitmailbox.com
public-inbox-index ffmpegdev
Example config snippet for mirrors.
AGPL code for this site: git clone https://public-inbox.org/public-inbox.git