diff --git a/src/dsp/lossless.c b/src/dsp/lossless.c index 20ff2f1b..c4598260 100644 --- a/src/dsp/lossless.c +++ b/src/dsp/lossless.c @@ -232,6 +232,112 @@ const float kSLog2Table[LOG_LOOKUP_IDX_MAX] = { 2010.27454072f, 2019.69737440f, 2029.12591044f, 2038.56012640f }; +const int8_t kPrefixEncodeCode[PREFIX_LOOKUP_IDX_MAX] = { + 0, 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, + 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, + 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, + 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, + 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, + 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, + 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, + 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, + 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, + 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, + 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, + 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, + 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, + 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, + 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, + 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, + 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17 +}; + +const int8_t kPrefixEncodeExtraBits[PREFIX_LOOKUP_IDX_MAX] = { + 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, + 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 +}; + +const uint8_t kPrefixEncodeExtraBitsVal[PREFIX_LOOKUP_IDX_MAX] = { + 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 2, 3, 0, 1, 2, 3, + 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, + 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, + 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, + 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, + 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, + 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, + 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, + 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, + 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, + 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, + 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, + 127, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, + 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, + 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, + 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, + 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, + 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, + 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126 +}; + float VP8LFastSLog2Slow(int v) { assert(v >= LOG_LOOKUP_IDX_MAX); if (v < APPROX_LOG_MAX) { diff --git a/src/dsp/lossless.h b/src/dsp/lossless.h index c143e6f9..46bfe198 100644 --- a/src/dsp/lossless.h +++ b/src/dsp/lossless.h @@ -99,6 +99,80 @@ static WEBP_INLINE float VP8LFastSLog2(int v) { return (v < LOG_LOOKUP_IDX_MAX) ? kSLog2Table[v] : VP8LFastSLog2Slow(v); } +// ----------------------------------------------------------------------------- +// PrefixEncode() + +// use GNU builtins where available. +#if defined(__GNUC__) && \ + ((__GNUC__ == 3 && __GNUC_MINOR__ >= 4) || __GNUC__ >= 4) +static WEBP_INLINE int BitsLog2Floor(uint32_t n) { + return 31 ^ __builtin_clz(n); +} +#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_IX86)) +#include +#pragma intrinsic(_BitScanReverse) + +static WEBP_INLINE int BitsLog2Floor(uint32_t n) { + unsigned long first_set_bit; + _BitScanReverse(&first_set_bit, n); + return first_set_bit; +} +#else +// Returns (int)floor(log2(n)). n must be > 0. +static WEBP_INLINE int BitsLog2Floor(uint32_t n) { + int log = 0; + uint32_t value = n; + int i; + + for (i = 4; i >= 0; --i) { + const int shift = (1 << i); + const uint32_t x = value >> shift; + if (x != 0) { + value = x; + log += shift; + } + } + return log; +} +#endif + +static WEBP_INLINE int VP8LBitsLog2Ceiling(uint32_t n) { + const int log_floor = BitsLog2Floor(n); + if (n == (n & ~(n - 1))) // zero or a power of two. + return log_floor; + else + return log_floor + 1; +} + +// Splitting of distance and length codes into prefixes and +// extra bits. The prefixes are encoded with an entropy code +// while the extra bits are stored just as normal bits. +static WEBP_INLINE void VP8LPrefixEncodeNoLUT(int distance, int* const code, + int* const extra_bits, + int* const extra_bits_value) { + const int highest_bit = BitsLog2Floor(--distance); + const int second_highest_bit = (distance >> (highest_bit - 1)) & 1; + *extra_bits = highest_bit - 1; + *extra_bits_value = distance & ((1 << *extra_bits) - 1); + *code = 2 * highest_bit + second_highest_bit; +} + +#define PREFIX_LOOKUP_IDX_MAX 512 +// These tables are derived using VP8LPrefixEncodeNoLUT. +extern const int8_t kPrefixEncodeCode[PREFIX_LOOKUP_IDX_MAX]; +extern const int8_t kPrefixEncodeExtraBits[PREFIX_LOOKUP_IDX_MAX]; +extern const uint8_t kPrefixEncodeExtraBitsVal[PREFIX_LOOKUP_IDX_MAX]; +static WEBP_INLINE void VP8LPrefixEncode(int distance, int* const code, + int* const extra_bits, + int* const extra_bits_value) { + if (distance < PREFIX_LOOKUP_IDX_MAX) { + *code = kPrefixEncodeCode[distance]; + *extra_bits = kPrefixEncodeExtraBits[distance]; + *extra_bits_value = kPrefixEncodeExtraBitsVal[distance]; + } else { + VP8LPrefixEncodeNoLUT(distance, code, extra_bits, extra_bits_value); + } +} // In-place difference of each component with mod 256. static WEBP_INLINE uint32_t VP8LSubPixels(uint32_t a, uint32_t b) { diff --git a/src/enc/backward_references.c b/src/enc/backward_references.c index 18fde228..373b6b8c 100644 --- a/src/enc/backward_references.c +++ b/src/enc/backward_references.c @@ -462,16 +462,16 @@ static WEBP_INLINE double GetCacheCost(const CostModel* const m, uint32_t idx) { static WEBP_INLINE double GetLengthCost(const CostModel* const m, uint32_t length) { - int code, extra_bits_count, extra_bits_value; - PrefixEncode(length, &code, &extra_bits_count, &extra_bits_value); - return m->literal_[VALUES_IN_BYTE + code] + extra_bits_count; + int code, extra_bits, extra_bits_val; + VP8LPrefixEncode(length, &code, &extra_bits, &extra_bits_val); + return m->literal_[VALUES_IN_BYTE + code] + extra_bits; } static WEBP_INLINE double GetDistanceCost(const CostModel* const m, uint32_t distance) { - int code, extra_bits_count, extra_bits_value; - PrefixEncode(distance, &code, &extra_bits_count, &extra_bits_value); - return m->distance_[code] + extra_bits_count; + int code, extra_bits, extra_bits_val; + VP8LPrefixEncode(distance, &code, &extra_bits, &extra_bits_val); + return m->distance_[code] + extra_bits; } static int BackwardReferencesHashChainDistanceOnly( diff --git a/src/enc/backward_references.h b/src/enc/backward_references.h index b0d18135..c89789bf 100644 --- a/src/enc/backward_references.h +++ b/src/enc/backward_references.h @@ -30,73 +30,6 @@ extern "C" { #define PIX_OR_COPY_CODES_MAX \ (NUM_LITERAL_CODES + NUM_LENGTH_CODES + (1 << MAX_COLOR_CACHE_BITS)) -// ----------------------------------------------------------------------------- -// PrefixEncode() - -// use GNU builtins where available. -#if defined(__GNUC__) && \ - ((__GNUC__ == 3 && __GNUC_MINOR__ >= 4) || __GNUC__ >= 4) -static WEBP_INLINE int BitsLog2Floor(uint32_t n) { - assert(n != 0); - return 31 ^ __builtin_clz(n); -} -#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_IX86)) -#include -#pragma intrinsic(_BitScanReverse) - -static WEBP_INLINE int BitsLog2Floor(uint32_t n) { - unsigned long first_set_bit; - assert(n != 0); - _BitScanReverse(&first_set_bit, n); - return first_set_bit; -} -#else -// Returns (int)floor(log2(n)). n must be > 0. -static WEBP_INLINE int BitsLog2Floor(uint32_t n) { - int log = 0; - uint32_t value = n; - int i; - - assert(n != 0); - for (i = 4; i >= 0; --i) { - const int shift = (1 << i); - const uint32_t x = value >> shift; - if (x != 0) { - value = x; - log += shift; - } - } - return log; -} -#endif - -static WEBP_INLINE int VP8LBitsLog2Ceiling(uint32_t n) { - const int log_floor = BitsLog2Floor(n); - if (n == (n & ~(n - 1))) // zero or a power of two. - return log_floor; - else - return log_floor + 1; -} - -// Splitting of distance and length codes into prefixes and -// extra bits. The prefixes are encoded with an entropy code -// while the extra bits are stored just as normal bits. -static WEBP_INLINE void PrefixEncode(int distance, int* const code, - int* const extra_bits_count, - int* const extra_bits_value) { - if (distance > 2) { // Collect the two most significant bits. - const int highest_bit = BitsLog2Floor(--distance); - const int second_highest_bit = (distance >> (highest_bit - 1)) & 1; - *extra_bits_count = highest_bit - 1; - *extra_bits_value = distance & ((1 << *extra_bits_count) - 1); - *code = 2 * highest_bit + second_highest_bit; - } else { - *extra_bits_count = 0; - *extra_bits_value = 0; - *code = (distance == 2) ? 1 : 0; - } -} - // ----------------------------------------------------------------------------- // PixOrCopy diff --git a/src/enc/histogram.c b/src/enc/histogram.c index 787ea5d1..f4989b00 100644 --- a/src/enc/histogram.c +++ b/src/enc/histogram.c @@ -90,12 +90,10 @@ void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const histo, int literal_ix = 256 + NUM_LENGTH_CODES + PixOrCopyCacheIdx(v); ++histo->literal_[literal_ix]; } else { - int code, extra_bits_count, extra_bits_value; - PrefixEncode(PixOrCopyLength(v), - &code, &extra_bits_count, &extra_bits_value); + int code, extra_bits, extra_bits_val; + VP8LPrefixEncode(PixOrCopyLength(v), &code, &extra_bits, &extra_bits_val); ++histo->literal_[256 + code]; - PrefixEncode(PixOrCopyDistance(v), - &code, &extra_bits_count, &extra_bits_value); + VP8LPrefixEncode(PixOrCopyDistance(v), &code, &extra_bits, &extra_bits_val); ++histo->distance_[code]; } } diff --git a/src/enc/vp8l.c b/src/enc/vp8l.c index 996c7fd0..6c53a1d8 100644 --- a/src/enc/vp8l.c +++ b/src/enc/vp8l.c @@ -448,12 +448,12 @@ static void StoreImageToBitMask( int bits, n_bits; int code, distance; - PrefixEncode(v->len, &code, &n_bits, &bits); + VP8LPrefixEncode(v->len, &code, &n_bits, &bits); WriteHuffmanCode(bw, codes, 256 + code); VP8LWriteBits(bw, n_bits, bits); distance = PixOrCopyDistance(v); - PrefixEncode(distance, &code, &n_bits, &bits); + VP8LPrefixEncode(distance, &code, &n_bits, &bits); WriteHuffmanCode(bw, codes + 4, code); VP8LWriteBits(bw, n_bits, bits); }