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-rw-r--r--libavcodec/bitstream.h379
1 files changed, 22 insertions, 357 deletions
diff --git a/libavcodec/bitstream.h b/libavcodec/bitstream.h
index 85f1af28c8..3fa63695d3 100644
--- a/libavcodec/bitstream.h
+++ b/libavcodec/bitstream.h
@@ -49,88 +49,6 @@ typedef struct BitstreamContext {
unsigned size_in_bits;
} BitstreamContext;
-static inline void refill_64(BitstreamContext *bc)
-{
-#if !UNCHECKED_BITSTREAM_READER
- if (bc->ptr >= bc->buffer_end)
- return;
-#endif
-
-#ifdef BITSTREAM_READER_LE
- bc->bits = AV_RL64(bc->ptr);
-#else
- bc->bits = AV_RB64(bc->ptr);
-#endif
- bc->ptr += 8;
- bc->bits_left = 64;
-}
-
-static inline void refill_32(BitstreamContext *bc)
-{
-#if !UNCHECKED_BITSTREAM_READER
- if (bc->ptr >= bc->buffer_end)
- return;
-#endif
-
-#ifdef BITSTREAM_READER_LE
- bc->bits = (uint64_t)AV_RL32(bc->ptr) << bc->bits_left | bc->bits;
-#else
- bc->bits = bc->bits | (uint64_t)AV_RB32(bc->ptr) << (32 - bc->bits_left);
-#endif
- bc->ptr += 4;
- bc->bits_left += 32;
-}
-
-/**
- * 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 bitstream_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_left = 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_left = 0;
- bc->bits = 0;
-
- 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 bitstream_init8(BitstreamContext *bc, const uint8_t *buffer,
- unsigned int byte_size)
-{
- if (byte_size > INT_MAX / 8)
- return AVERROR_INVALIDDATA;
- return bitstream_init(bc, buffer, byte_size * 8);
-}
-
/**
* Return number of bits already read.
*/
@@ -155,235 +73,6 @@ static inline int bitstream_bits_left(const BitstreamContext *bc)
return (bc->buffer - bc->ptr) * 8 + bc->size_in_bits + bc->bits_left;
}
-static inline uint64_t get_val(BitstreamContext *bc, unsigned int n)
-{
- uint64_t ret;
-
-#ifdef BITSTREAM_READER_LE
- ret = bc->bits & ((UINT64_C(1) << n) - 1);
- bc->bits >>= n;
-#else
- ret = bc->bits >> (64 - n);
- bc->bits <<= n;
-#endif
- bc->bits_left -= n;
-
- return ret;
-}
-
-/**
- * Return one bit from the buffer.
- */
-static inline unsigned int bitstream_read_bit(BitstreamContext *bc)
-{
- if (!bc->bits_left)
- refill_64(bc);
-
- return get_val(bc, 1);
-}
-
-/**
- * Return n bits from the buffer, n has to be in the 0-63 range.
- */
-static inline uint64_t bitstream_read_63(BitstreamContext *bc, unsigned int n)
-{
- uint64_t ret = 0;
-#ifdef BITSTREAM_READER_LE
- uint64_t left = 0;
-#endif
-
- if (!n)
- return 0;
-
- if (n > bc->bits_left) {
- n -= bc->bits_left;
-#ifdef BITSTREAM_READER_LE
- left = bc->bits_left;
-#endif
- ret = get_val(bc, bc->bits_left);
- refill_64(bc);
- }
-
-#ifdef BITSTREAM_READER_LE
- ret = get_val(bc, n) << left | ret;
-#else
- ret = get_val(bc, n) | ret << n;
-#endif
-
- return ret;
-}
-
-/**
- * Return n bits from the buffer, n has to be in the 0-32 range.
- */
-static inline uint32_t bitstream_read(BitstreamContext *bc, unsigned int n)
-{
- if (!n)
- return 0;
-
- if (n > bc->bits_left) {
- refill_32(bc);
- if (bc->bits_left < 32)
- bc->bits_left = n;
- }
-
- return get_val(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 bitstream_read_signed(BitstreamContext *bc, unsigned int n)
-{
- return sign_extend(bitstream_read(bc, n), n);
-}
-
-static inline unsigned int show_val(BitstreamContext *bc, unsigned int n)
-{
-#ifdef BITSTREAM_READER_LE
- return bc->bits & ((UINT64_C(1) << n) - 1);
-#else
- return bc->bits >> (64 - n);
-#endif
-}
-
-/**
- * Return n bits from the buffer but do not change the buffer state.
- * n has to be in the 0-32 range.
- */
-static inline unsigned int bitstream_peek(BitstreamContext *bc, unsigned int n)
-{
- if (n > bc->bits_left)
- refill_32(bc);
-
- return show_val(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 bitstream_peek_signed(BitstreamContext *bc, unsigned int n)
-{
- return sign_extend(bitstream_peek(bc, n), n);
-}
-
-static inline void skip_remaining(BitstreamContext *bc, unsigned int n)
-{
-#ifdef BITSTREAM_READER_LE
- bc->bits >>= n;
-#else
- bc->bits <<= n;
-#endif
- bc->bits_left -= n;
-}
-
-/**
- * Skip n bits in the buffer.
- */
-static inline void bitstream_skip(BitstreamContext *bc, unsigned int n)
-{
- if (n < bc->bits_left)
- skip_remaining(bc, n);
- else {
- n -= bc->bits_left;
- bc->bits = 0;
- bc->bits_left = 0;
-
- if (n >= 64) {
- unsigned int skip = n / 8;
-
- n -= skip * 8;
- bc->ptr += skip;
- }
- refill_64(bc);
- if (n)
- skip_remaining(bc, n);
- }
-}
-
-/**
- * Seek to the given bit position.
- */
-static inline void bitstream_seek(BitstreamContext *bc, unsigned pos)
-{
- bc->ptr = bc->buffer;
- bc->bits = 0;
- bc->bits_left = 0;
-
- bitstream_skip(bc, pos);
-}
-
-/**
- * Skip bits to a byte boundary.
- */
-static inline const uint8_t *bitstream_align(BitstreamContext *bc)
-{
- unsigned int n = -bitstream_tell(bc) & 7;
- if (n)
- bitstream_skip(bc, n);
- return bc->buffer + (bitstream_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 bitstream_read_xbits(BitstreamContext *bc, unsigned int n)
-{
- int32_t cache = bitstream_peek(bc, 32);
- int sign = ~cache >> 31;
- 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 bitstream_decode012(BitstreamContext *bc)
-{
- if (!bitstream_read_bit(bc))
- return 0;
- else
- return bitstream_read_bit(bc) + 1;
-}
-
-/**
- * Return decoded truncated unary code for the values 2, 1, 0.
- */
-static inline int bitstream_decode210(BitstreamContext *bc)
-{
- if (bitstream_read_bit(bc))
- return 0;
- else
- return 2 - bitstream_read_bit(bc);
-}
-
-/* Read sign bit and flip the sign of the provided value accordingly. */
-static inline int bitstream_apply_sign(BitstreamContext *bc, int val)
-{
- int sign = bitstream_read_signed(bc, 1);
- return (val ^ sign) - sign;
-}
-
-static inline int bitstream_skip_1stop_8data(BitstreamContext *s)
-{
- if (bitstream_bits_left(s) <= 0)
- return AVERROR_INVALIDDATA;
-
- while (bitstream_read(s, 1)) {
- bitstream_skip(s, 8);
- if (bitstream_bits_left(s) <= 0)
- return AVERROR_INVALIDDATA;
- }
-
- return 0;
-}
-
/* Unwind the cache so a refill_32 can fill it again. */
static inline void bitstream_unwind(BitstreamContext *bc)
{
@@ -412,52 +101,28 @@ static inline void bitstream_unget(BitstreamContext *bc, uint64_t value,
bc->bits_left += amount;
}
-/**
- * Return the LUT element for the given bitstream configuration.
- */
-static inline int set_idx(BitstreamContext *bc, int code, int *n, int *nb_bits,
- VLC_TYPE (*table)[2])
-{
- unsigned idx;
-
- *nb_bits = -*n;
- idx = bitstream_peek(bc, *nb_bits) + code;
- *n = table[idx][1];
-
- return table[idx][0];
-}
-
-/**
- * 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 bitstream_read_vlc(BitstreamContext *bc, VLC_TYPE (*table)[2],
- int bits, int max_depth)
-{
- int nb_bits;
- unsigned idx = bitstream_peek(bc, bits);
- int code = table[idx][0];
- int n = table[idx][1];
-
- if (max_depth > 1 && n < 0) {
- skip_remaining(bc, bits);
- code = set_idx(bc, code, &n, &nb_bits, table);
- if (max_depth > 2 && n < 0) {
- skip_remaining(bc, nb_bits);
- code = set_idx(bc, code, &n, &nb_bits, table);
- }
- }
- skip_remaining(bc, n);
-
- return code;
-}
+#define BITSTREAM_LE
+#include "bitstream_template.h"
+
+#undef BITSTREAM_LE
+#include "bitstream_template.h"
+
+#define bitstream_init bitstream_init_be
+#define bitstream_init8 bitstream_init8_be
+#define bitstream_read_bit bitstream_read_bit_be
+#define bitstream_read_63 bitstream_read_63_be
+#define bitstream_read bitstream_read_be
+#define bitstream_read_signed bitstream_read_signed_be
+#define bitstream_peek bitstream_peek_be
+#define bitstream_peek_signed bitstream_peek_signed_be
+#define bitstream_skip bitstream_skip_be
+#define bitstream_seek bitstream_seek_be
+#define bitstream_align bitstream_align_be
+#define bitstream_read_xbits bitstream_read_xbits_be
+#define bitstream_decode012 bitstream_decode012_be
+#define bitstream_decode210 bitstream_decode210_be
+#define bitstream_apply_sign bitstream_apply_sign_be
+#define bitstream_read_vlc bitstream_read_vlc_be
#define BITSTREAM_RL_VLC(level, run, bc, table, bits, max_depth) \
do { \
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 01:18:12 +0000