/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkImageInfo_DEFINED
#define SkImageInfo_DEFINED
#include "SkMath.h"
#include "SkRect.h"
#include "SkSize.h"
class SkReadBuffer;
class SkWriteBuffer;
/**
* Describes how to interpret the alpha component of a pixel.
*/
enum SkAlphaType {
kUnknown_SkAlphaType,
/**
* All pixels are stored as opaque. This differs slightly from kIgnore in
* that kOpaque has correct "opaque" values stored in the pixels, while
* kIgnore may not, but in both cases the caller should treat the pixels
* as opaque.
*/
kOpaque_SkAlphaType,
/**
* All pixels have their alpha premultiplied in their color components.
* This is the natural format for the rendering target pixels.
*/
kPremul_SkAlphaType,
/**
* All pixels have their color components stored without any regard to the
* alpha. e.g. this is the default configuration for PNG images.
*
* This alpha-type is ONLY supported for input images. Rendering cannot
* generate this on output.
*/
kUnpremul_SkAlphaType,
kLastEnum_SkAlphaType = kUnpremul_SkAlphaType
};
static inline bool SkAlphaTypeIsOpaque(SkAlphaType at) {
return kOpaque_SkAlphaType == at;
}
static inline bool SkAlphaTypeIsValid(unsigned value) {
return value <= kLastEnum_SkAlphaType;
}
///////////////////////////////////////////////////////////////////////////////
/**
* Describes how to interpret the components of a pixel.
*
* kN32_SkColorType is an alias for whichever 32bit ARGB format is the "native"
* form for skia's blitters. Use this if you don't have a swizzle preference
* for 32bit pixels.
*/
enum SkColorType {
kUnknown_SkColorType,
kAlpha_8_SkColorType,
kRGB_565_SkColorType,
kARGB_4444_SkColorType,
kRGBA_8888_SkColorType,
kBGRA_8888_SkColorType,
kIndex_8_SkColorType,
kGray_8_SkColorType,
kRGBA_F16_SkColorType,
kLastEnum_SkColorType = kRGBA_F16_SkColorType,
#if SK_PMCOLOR_BYTE_ORDER(B,G,R,A)
kN32_SkColorType = kBGRA_8888_SkColorType,
#elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A)
kN32_SkColorType = kRGBA_8888_SkColorType,
#else
#error "SK_*32_SHFIT values must correspond to BGRA or RGBA byte order"
#endif
};
static int SkColorTypeBytesPerPixel(SkColorType ct) {
static const uint8_t gSize[] = {
0, // Unknown
1, // Alpha_8
2, // RGB_565
2, // ARGB_4444
4, // RGBA_8888
4, // BGRA_8888
1, // kIndex_8
1, // kGray_8
8, // kRGBA_F16
};
static_assert(SK_ARRAY_COUNT(gSize) == (size_t)(kLastEnum_SkColorType + 1),
"size_mismatch_with_SkColorType_enum");
SkASSERT((size_t)ct < SK_ARRAY_COUNT(gSize));
return gSize[ct];
}
static inline size_t SkColorTypeMinRowBytes(SkColorType ct, int width) {
return width * SkColorTypeBytesPerPixel(ct);
}
static inline bool SkColorTypeIsValid(unsigned value) {
return value <= kLastEnum_SkColorType;
}
static inline size_t SkColorTypeComputeOffset(SkColorType ct, int x, int y, size_t rowBytes) {
int shift = 0;
switch (SkColorTypeBytesPerPixel(ct)) {
case 8: shift = 3; break;
case 4: shift = 2; break;
case 2: shift = 1; break;
case 1: shift = 0; break;
default: return 0;
}
return y * rowBytes + (x << shift);
}
///////////////////////////////////////////////////////////////////////////////
/**
* Return true if alphaType is supported by colorType. If there is a canonical
* alphaType for this colorType, return it in canonical.
*/
bool SkColorTypeValidateAlphaType(SkColorType colorType, SkAlphaType alphaType,
SkAlphaType* canonical = NULL);
///////////////////////////////////////////////////////////////////////////////
/**
* Describes the color space a YUV pixel.
*/
enum SkYUVColorSpace {
/** Standard JPEG color space. */
kJPEG_SkYUVColorSpace,
/** SDTV standard Rec. 601 color space. Uses "studio swing" [16, 235] color
range. See http://en.wikipedia.org/wiki/Rec._601 for details. */
kRec601_SkYUVColorSpace,
/** HDTV standard Rec. 709 color space. Uses "studio swing" [16, 235] color
range. See http://en.wikipedia.org/wiki/Rec._709 for details. */
kRec709_SkYUVColorSpace,
kLastEnum_SkYUVColorSpace = kRec709_SkYUVColorSpace
};
///////////////////////////////////////////////////////////////////////////////
enum SkColorProfileType {
kLinear_SkColorProfileType,
kSRGB_SkColorProfileType,
kLastEnum_SkColorProfileType = kSRGB_SkColorProfileType
};
/**
* Describe an image's dimensions and pixel type.
* Used for both src images and render-targets (surfaces).
*/
struct SK_API SkImageInfo {
public:
SkImageInfo()
: fWidth(0)
, fHeight(0)
, fColorType(kUnknown_SkColorType)
, fAlphaType(kUnknown_SkAlphaType)
, fProfileType(kLinear_SkColorProfileType)
{}
static SkImageInfo Make(int width, int height, SkColorType ct, SkAlphaType at,
SkColorProfileType pt = kLinear_SkColorProfileType) {
return SkImageInfo(width, height, ct, at, pt);
}
/**
* Sets colortype to the native ARGB32 type.
*/
static SkImageInfo MakeN32(int width, int height, SkAlphaType at,
SkColorProfileType pt = kLinear_SkColorProfileType) {
return SkImageInfo(width, height, kN32_SkColorType, at, pt);
}
/**
* Sets colortype to the native ARGB32 type, and the alphatype to premul.
*/
static SkImageInfo MakeN32Premul(int width, int height,
SkColorProfileType pt = kLinear_SkColorProfileType) {
return SkImageInfo(width, height, kN32_SkColorType, kPremul_SkAlphaType, pt);
}
/**
* Sets colortype to the native ARGB32 type, and the alphatype to premul.
*/
static SkImageInfo MakeN32Premul(const SkISize& size,
SkColorProfileType pt = kLinear_SkColorProfileType) {
return MakeN32Premul(size.width(), size.height(), pt);
}
static SkImageInfo MakeA8(int width, int height) {
return SkImageInfo(width, height, kAlpha_8_SkColorType, kPremul_SkAlphaType,
kLinear_SkColorProfileType);
}
static SkImageInfo MakeUnknown(int width, int height) {
return SkImageInfo(width, height, kUnknown_SkColorType, kUnknown_SkAlphaType,
kLinear_SkColorProfileType);
}
static SkImageInfo MakeUnknown() {
return SkImageInfo();
}
int width() const { return fWidth; }
int height() const { return fHeight; }
SkColorType colorType() const { return fColorType; }
SkAlphaType alphaType() const { return fAlphaType; }
SkColorProfileType profileType() const { return fProfileType; }
bool isEmpty() const { return fWidth <= 0 || fHeight <= 0; }
bool isOpaque() const {
return SkAlphaTypeIsOpaque(fAlphaType);
}
bool isLinear() const { return kLinear_SkColorProfileType == fProfileType; }
bool isSRGB() const { return kSRGB_SkColorProfileType == fProfileType; }
SkISize dimensions() const { return SkISize::Make(fWidth, fHeight); }
SkIRect bounds() const { return SkIRect::MakeWH(fWidth, fHeight); }
/**
* Return a new ImageInfo with the same colortype and alphatype as this info,
* but with the specified width and height.
*/
SkImageInfo makeWH(int newWidth, int newHeight) const {
return SkImageInfo::Make(newWidth, newHeight, fColorType, fAlphaType, fProfileType);
}
SkImageInfo makeAlphaType(SkAlphaType newAlphaType) const {
return SkImageInfo::Make(fWidth, fHeight, fColorType, newAlphaType, fProfileType);
}
SkImageInfo makeColorType(SkColorType newColorType) const {
return SkImageInfo::Make(fWidth, fHeight, newColorType, fAlphaType, fProfileType);
}
int bytesPerPixel() const {
return SkColorTypeBytesPerPixel(fColorType);
}
uint64_t minRowBytes64() const {
return sk_64_mul(fWidth, this->bytesPerPixel());
}
size_t minRowBytes() const {
return (size_t)this->minRowBytes64();
}
size_t computeOffset(int x, int y, size_t rowBytes) const {
SkASSERT((unsigned)x < (unsigned)fWidth);
SkASSERT((unsigned)y < (unsigned)fHeight);
return SkColorTypeComputeOffset(fColorType, x, y, rowBytes);
}
bool operator==(const SkImageInfo& other) const {
return 0 == memcmp(this, &other, sizeof(other));
}
bool operator!=(const SkImageInfo& other) const {
return 0 != memcmp(this, &other, sizeof(other));
}
void unflatten(SkReadBuffer&);
void flatten(SkWriteBuffer&) const;
int64_t getSafeSize64(size_t rowBytes) const {
if (0 == fHeight) {
return 0;
}
return sk_64_mul(fHeight - 1, rowBytes) + fWidth * this->bytesPerPixel();
}
size_t getSafeSize(size_t rowBytes) const {
int64_t size = this->getSafeSize64(rowBytes);
if (!sk_64_isS32(size)) {
return 0;
}
return sk_64_asS32(size);
}
bool validRowBytes(size_t rowBytes) const {
uint64_t rb = sk_64_mul(fWidth, this->bytesPerPixel());
return rowBytes >= rb;
}
SkDEBUGCODE(void validate() const;)
private:
int fWidth;
int fHeight;
SkColorType fColorType;
SkAlphaType fAlphaType;
SkColorProfileType fProfileType;
SkImageInfo(int width, int height, SkColorType ct, SkAlphaType at, SkColorProfileType pt)
: fWidth(width)
, fHeight(height)
, fColorType(ct)
, fAlphaType(at)
, fProfileType(pt)
{}
};
#endif