diff options
Diffstat (limited to 'drivers/webp/utils/utils.h')
| -rw-r--r-- | drivers/webp/utils/utils.h | 116 |
1 files changed, 107 insertions, 9 deletions
diff --git a/drivers/webp/utils/utils.h b/drivers/webp/utils/utils.h index 316ac90612..d0e1cb250a 100644 --- a/drivers/webp/utils/utils.h +++ b/drivers/webp/utils/utils.h @@ -1,20 +1,25 @@ // Copyright 2012 Google Inc. All Rights Reserved. // -// This code is licensed under the same terms as WebM: -// Software License Agreement: http://www.webmproject.org/license/software/ -// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING file in the root of the source +// tree. An additional intellectual property rights grant can be found +// in the file PATENTS. All contributing project authors may +// be found in the AUTHORS file in the root of the source tree. // ----------------------------------------------------------------------------- // // Misc. common utility functions // -// Author: Skal (pascal.massimino@gmail.com) +// Authors: Skal (pascal.massimino@gmail.com) +// Urvang (urvang@google.com) #ifndef WEBP_UTILS_UTILS_H_ #define WEBP_UTILS_UTILS_H_ -#include "../types.h" +#include <assert.h> -#if defined(__cplusplus) || defined(c_plusplus) +#include "webp/types.h" + +#ifdef __cplusplus extern "C" { #endif @@ -30,14 +35,107 @@ extern "C" { // somewhere (like: malloc(num_pixels * sizeof(*something))). That's why this // safe malloc() borrows the signature from calloc(), pointing at the dangerous // underlying multiply involved. -void* WebPSafeMalloc(uint64_t nmemb, size_t size); +WEBP_EXTERN(void*) WebPSafeMalloc(uint64_t nmemb, size_t size); // Note that WebPSafeCalloc() expects the second argument type to be 'size_t' // in order to favor the "calloc(num_foo, sizeof(foo))" pattern. -void* WebPSafeCalloc(uint64_t nmemb, size_t size); +WEBP_EXTERN(void*) WebPSafeCalloc(uint64_t nmemb, size_t size); + +// Companion deallocation function to the above allocations. +WEBP_EXTERN(void) WebPSafeFree(void* const ptr); + +//------------------------------------------------------------------------------ +// Alignment + +#define WEBP_ALIGN_CST 31 +#define WEBP_ALIGN(PTR) ((uintptr_t)((PTR) + WEBP_ALIGN_CST) & ~WEBP_ALIGN_CST) + +//------------------------------------------------------------------------------ +// Reading/writing data. + +// Read 16, 24 or 32 bits stored in little-endian order. +static WEBP_INLINE int GetLE16(const uint8_t* const data) { + return (int)(data[0] << 0) | (data[1] << 8); +} + +static WEBP_INLINE int GetLE24(const uint8_t* const data) { + return GetLE16(data) | (data[2] << 16); +} + +static WEBP_INLINE uint32_t GetLE32(const uint8_t* const data) { + return GetLE16(data) | ((uint32_t)GetLE16(data + 2) << 16); +} + +// Store 16, 24 or 32 bits in little-endian order. +static WEBP_INLINE void PutLE16(uint8_t* const data, int val) { + assert(val < (1 << 16)); + data[0] = (val >> 0); + data[1] = (val >> 8); +} + +static WEBP_INLINE void PutLE24(uint8_t* const data, int val) { + assert(val < (1 << 24)); + PutLE16(data, val & 0xffff); + data[2] = (val >> 16); +} + +static WEBP_INLINE void PutLE32(uint8_t* const data, uint32_t val) { + PutLE16(data, (int)(val & 0xffff)); + PutLE16(data + 2, (int)(val >> 16)); +} + +// Returns (int)floor(log2(n)). n must be > 0. +// 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) && _MSC_VER > 1310 && \ + (defined(_M_X64) || defined(_M_IX86)) +#include <intrin.h> +#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 +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 + +//------------------------------------------------------------------------------ +// Pixel copying. + +struct WebPPicture; + +// Copy width x height pixels from 'src' to 'dst' honoring the strides. +WEBP_EXTERN(void) WebPCopyPlane(const uint8_t* src, int src_stride, + uint8_t* dst, int dst_stride, + int width, int height); + +// Copy ARGB pixels from 'src' to 'dst' honoring strides. 'src' and 'dst' are +// assumed to be already allocated and using ARGB data. +WEBP_EXTERN(void) WebPCopyPixels(const struct WebPPicture* const src, + struct WebPPicture* const dst); //------------------------------------------------------------------------------ -#if defined(__cplusplus) || defined(c_plusplus) +#ifdef __cplusplus } // extern "C" #endif |