From 78c8a765369d3974b50c08355fd872637653cd08 Mon Sep 17 00:00:00 2001 From: Paul B Mahol Date: Tue, 26 Mar 2019 11:10:54 +0100 Subject: [PATCH] avcodec/get_bits: unbreak get_bits_le() with cached reader --- libavcodec/get_bits.h | 82 +++++++++++++++++++++++++++++------------ libavcodec/utvideodec.c | 4 +- 2 files changed, 60 insertions(+), 26 deletions(-) diff --git a/libavcodec/get_bits.h b/libavcodec/get_bits.h index c2f267186e..c4ab607744 100644 --- a/libavcodec/get_bits.h +++ b/libavcodec/get_bits.h @@ -226,34 +226,32 @@ static inline int get_bits_count(const GetBitContext *s) } #if CACHED_BITSTREAM_READER -static inline void refill_32(GetBitContext *s) +static inline void refill_32(GetBitContext *s, int is_le) { #if !UNCHECKED_BITSTREAM_READER if (s->index >> 3 >= s->buffer_end - s->buffer) return; #endif -#ifdef BITSTREAM_READER_LE + if (is_le) s->cache = (uint64_t)AV_RL32(s->buffer + (s->index >> 3)) << s->bits_left | s->cache; -#else + else s->cache = s->cache | (uint64_t)AV_RB32(s->buffer + (s->index >> 3)) << (32 - s->bits_left); -#endif s->index += 32; s->bits_left += 32; } -static inline void refill_64(GetBitContext *s) +static inline void refill_64(GetBitContext *s, int is_le) { #if !UNCHECKED_BITSTREAM_READER if (s->index >> 3 >= s->buffer_end - s->buffer) return; #endif -#ifdef BITSTREAM_READER_LE + if (is_le) s->cache = AV_RL64(s->buffer + (s->index >> 3)); -#else + else s->cache = AV_RB64(s->buffer + (s->index >> 3)); -#endif s->index += 64; s->bits_left = 64; } @@ -385,7 +383,11 @@ static inline unsigned int get_bits(GetBitContext *s, int n) av_assert2(n>0 && n<=32); if (n > s->bits_left) { - refill_32(s); +#ifdef BITSTREAM_READER_LE + refill_32(s, 1); +#else + refill_32(s, 0); +#endif if (s->bits_left < 32) s->bits_left = n; } @@ -420,7 +422,7 @@ static inline unsigned int get_bits_le(GetBitContext *s, int n) #if CACHED_BITSTREAM_READER av_assert2(n>0 && n<=32); if (n > s->bits_left) { - refill_32(s); + refill_32(s, 1); if (s->bits_left < 32) s->bits_left = n; } @@ -446,7 +448,11 @@ static inline unsigned int show_bits(GetBitContext *s, int n) register unsigned int tmp; #if CACHED_BITSTREAM_READER if (n > s->bits_left) - refill_32(s); +#ifdef BITSTREAM_READER_LE + refill_32(s, 1); +#else + refill_32(s, 0); +#endif tmp = show_val(s, n); #else @@ -474,7 +480,11 @@ static inline void skip_bits(GetBitContext *s, int n) n -= skip; s->index += skip; } - refill_64(s); +#ifdef BITSTREAM_READER_LE + refill_64(s, 1); +#else + refill_64(s, 0); +#endif if (n) skip_remaining(s, n); } @@ -489,7 +499,11 @@ static inline unsigned int get_bits1(GetBitContext *s) { #if CACHED_BITSTREAM_READER if (!s->bits_left) - refill_64(s); +#ifdef BITSTREAM_READER_LE + refill_64(s, 1); +#else + refill_64(s, 0); +#endif #ifdef BITSTREAM_READER_LE return get_val(s, 1, 1); @@ -605,16 +619,8 @@ static inline int check_marker(void *logctx, GetBitContext *s, const char *msg) return bit; } -/** - * Initialize GetBitContext. - * @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 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 int init_get_bits(GetBitContext *s, const uint8_t *buffer, - int bit_size) +static inline int init_get_bits_xe(GetBitContext *s, const uint8_t *buffer, + int bit_size, int is_le) { int buffer_size; int ret = 0; @@ -634,12 +640,32 @@ static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer, s->index = 0; #if CACHED_BITSTREAM_READER - refill_64(s); + s->cache = 0; + s->bits_left = 0; + refill_64(s, is_le); #endif return ret; } +/** + * Initialize GetBitContext. + * @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 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 int init_get_bits(GetBitContext *s, const uint8_t *buffer, + int bit_size) +{ +#ifdef BITSTREAM_READER_LE + return init_get_bits_xe(s, buffer, bit_size, 1); +#else + return init_get_bits_xe(s, buffer, bit_size, 0); +#endif +} + /** * Initialize GetBitContext. * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes @@ -656,6 +682,14 @@ static inline int init_get_bits8(GetBitContext *s, const uint8_t *buffer, return init_get_bits(s, buffer, byte_size * 8); } +static inline int init_get_bits8_le(GetBitContext *s, const uint8_t *buffer, + int byte_size) +{ + if (byte_size > INT_MAX / 8 || byte_size < 0) + byte_size = -1; + return init_get_bits_xe(s, buffer, byte_size * 8, 1); +} + static inline const uint8_t *align_get_bits(GetBitContext *s) { int n = -get_bits_count(s) & 7; diff --git a/libavcodec/utvideodec.c b/libavcodec/utvideodec.c index 3891df3570..d5af9d53a8 100644 --- a/libavcodec/utvideodec.c +++ b/libavcodec/utvideodec.c @@ -258,11 +258,11 @@ static int decode_plane(UtvideoContext *c, int plane_no, GetBitContext cbit, pbit; uint8_t *dest, *p; - ret = init_get_bits8(&cbit, c->control_stream[plane_no][slice], c->control_stream_size[plane_no][slice]); + ret = init_get_bits8_le(&cbit, c->control_stream[plane_no][slice], c->control_stream_size[plane_no][slice]); if (ret < 0) return ret; - ret = init_get_bits8(&pbit, c->packed_stream[plane_no][slice], c->packed_stream_size[plane_no][slice]); + ret = init_get_bits8_le(&pbit, c->packed_stream[plane_no][slice], c->packed_stream_size[plane_no][slice]); if (ret < 0) return ret;