// static
SkBitmap ImageOperations::ResizeBasic(const SkBitmap& source,
ResizeMethod method,
int dest_width, int dest_height,
const SkIRect& dest_subset,
void* dest_pixels /* = nullptr */) {
// Ensure that the ResizeMethod enumeration is sound.
SkASSERT(((RESIZE_FIRST_QUALITY_METHOD <= method) &&
(method <= RESIZE_LAST_QUALITY_METHOD)) ||
((RESIZE_FIRST_ALGORITHM_METHOD <= method) &&
(method <= RESIZE_LAST_ALGORITHM_METHOD)));
// If the size of source or destination is 0, i.e. 0x0, 0xN or Nx0, just
// return empty.
if (source.width() < 1 || source.height() < 1 ||
dest_width < 1 || dest_height < 1)
return SkBitmap();
method = ResizeMethodToAlgorithmMethod(method);
// Check that we deal with an "algorithm methods" from this point onward.
SkASSERT((ImageOperations::RESIZE_FIRST_ALGORITHM_METHOD <= method) &&
(method <= ImageOperations::RESIZE_LAST_ALGORITHM_METHOD));
SkAutoLockPixels locker(source);
if (!source.readyToDraw())
return SkBitmap();
ConvolutionFilter1D x_filter;
ConvolutionFilter1D y_filter;
resize::ComputeFilters(method, source.width(), dest_width, dest_subset.fLeft, dest_subset.width(), &x_filter);
resize::ComputeFilters(method, source.height(), dest_height, dest_subset.fTop, dest_subset.height(), &y_filter);
// Get a source bitmap encompassing this touched area. We construct the
// offsets and row strides such that it looks like a new bitmap, while
// referring to the old data.
const uint8_t* source_subset =
reinterpret_cast<const uint8_t*>(source.getPixels());
// Convolve into the result.
SkBitmap result;
SkImageInfo info = SkImageInfo::Make(dest_subset.width(),
dest_subset.height(),
kBGRA_8888_SkColorType,
kPremul_SkAlphaType);
if (dest_pixels) {
result.installPixels(info, dest_pixels, info.minRowBytes());
} else {
result.allocPixels(info);
}
if (!result.readyToDraw())
return SkBitmap();
BGRAConvolve2D(source_subset, static_cast<int>(source.rowBytes()),
!source.isOpaque(), x_filter, y_filter,
static_cast<int>(result.rowBytes()),
static_cast<unsigned char*>(result.getPixels()));
// Preserve the "opaque" flag for use as an optimization later.
result.setAlphaType(source.alphaType());
return result;
}
SkBitmap ImageFrameGenerator::tryToResumeDecode(const SkISize& scaledSize, size_t index)
{
TRACE_EVENT1("blink", "ImageFrameGenerator::tryToResumeDecodeAndScale", "index", static_cast<int>(index));
ImageDecoder* decoder = 0;
const bool resumeDecoding = ImageDecodingStore::instance().lockDecoder(this, m_fullSize, &decoder);
ASSERT(!resumeDecoding || decoder);
SkBitmap fullSizeImage;
bool complete = decode(index, &decoder, &fullSizeImage);
if (!decoder)
return SkBitmap();
if (index >= m_frameComplete.size())
m_frameComplete.resize(index + 1);
m_frameComplete[index] = complete;
// If we are not resuming decoding that means the decoder is freshly
// created and we have ownership. If we are resuming decoding then
// the decoder is owned by ImageDecodingStore.
OwnPtr<ImageDecoder> decoderContainer;
if (!resumeDecoding)
decoderContainer = adoptPtr(decoder);
if (fullSizeImage.isNull()) {
// If decode has failed and resulted an empty image we can save work
// in the future by returning early.
m_decodeFailedAndEmpty = !m_isMultiFrame && decoder->failed();
if (resumeDecoding)
ImageDecodingStore::instance().unlockDecoder(this, decoder);
return SkBitmap();
}
// If the image generated is complete then there is no need to keep
// the decoder. For multi-frame images, if all frames in the image are
// decoded, we remove the decoder.
bool removeDecoder;
if (m_isMultiFrame) {
size_t decodedFrameCount = 0;
for (Vector<bool>::iterator it = m_frameComplete.begin(); it != m_frameComplete.end(); ++it) {
if (*it)
decodedFrameCount++;
}
removeDecoder = m_frameCount && (decodedFrameCount == m_frameCount);
} else {
removeDecoder = complete;
}
if (resumeDecoding) {
if (removeDecoder) {
ImageDecodingStore::instance().removeDecoder(this, decoder);
m_frameComplete.clear();
} else {
ImageDecodingStore::instance().unlockDecoder(this, decoder);
}
} else if (!removeDecoder) {
ImageDecodingStore::instance().insertDecoder(this, decoderContainer.release());
}
return fullSizeImage;
}
// static
SkBitmap ImageOperations::ResizeSubpixel(const SkBitmap& source,
int dest_width, int dest_height,
const SkIRect& dest_subset) {
// Currently only works on Linux/BSD because these are the only platforms
// where SkFontHost::GetSubpixelOrder is defined.
#if defined(XP_UNIX)
// Understand the display.
const SkFontHost::LCDOrder order = SkFontHost::GetSubpixelOrder();
const SkFontHost::LCDOrientation orientation =
SkFontHost::GetSubpixelOrientation();
// Decide on which dimension, if any, to deploy subpixel rendering.
int w = 1;
int h = 1;
switch (orientation) {
case SkFontHost::kHorizontal_LCDOrientation:
w = dest_width < source.width() ? 3 : 1;
break;
case SkFontHost::kVertical_LCDOrientation:
h = dest_height < source.height() ? 3 : 1;
break;
}
// Resize the image.
const int width = dest_width * w;
const int height = dest_height * h;
SkIRect subset = { dest_subset.fLeft, dest_subset.fTop,
dest_subset.fLeft + dest_subset.width() * w,
dest_subset.fTop + dest_subset.height() * h };
SkBitmap img = ResizeBasic(source, ImageOperations::RESIZE_LANCZOS3, width,
height, subset);
const int row_words = img.rowBytes() / 4;
if (w == 1 && h == 1)
return img;
// Render into subpixels.
SkBitmap result;
SkImageInfo info = SkImageInfo::Make(dest_subset.width(),
dest_subset.height(),
kBGRA_8888_SkColorType,
kPremul_SkAlphaType);
result.allocPixels(info);
if (!result.readyToDraw())
return img;
SkAutoLockPixels locker(img);
if (!img.readyToDraw())
return img;
uint32_t* src_row = img.getAddr32(0, 0);
uint32_t* dst_row = result.getAddr32(0, 0);
for (int y = 0; y < dest_subset.height(); y++) {
uint32_t* src = src_row;
uint32_t* dst = dst_row;
for (int x = 0; x < dest_subset.width(); x++, src += w, dst++) {
uint8_t r = 0, g = 0, b = 0, a = 0;
switch (order) {
case SkFontHost::kRGB_LCDOrder:
switch (orientation) {
case SkFontHost::kHorizontal_LCDOrientation:
r = SkGetPackedR32(src[0]);
g = SkGetPackedG32(src[1]);
b = SkGetPackedB32(src[2]);
a = SkGetPackedA32(src[1]);
break;
case SkFontHost::kVertical_LCDOrientation:
r = SkGetPackedR32(src[0 * row_words]);
g = SkGetPackedG32(src[1 * row_words]);
b = SkGetPackedB32(src[2 * row_words]);
a = SkGetPackedA32(src[1 * row_words]);
break;
}
break;
case SkFontHost::kBGR_LCDOrder:
switch (orientation) {
case SkFontHost::kHorizontal_LCDOrientation:
b = SkGetPackedB32(src[0]);
g = SkGetPackedG32(src[1]);
r = SkGetPackedR32(src[2]);
a = SkGetPackedA32(src[1]);
break;
case SkFontHost::kVertical_LCDOrientation:
b = SkGetPackedB32(src[0 * row_words]);
g = SkGetPackedG32(src[1 * row_words]);
r = SkGetPackedR32(src[2 * row_words]);
a = SkGetPackedA32(src[1 * row_words]);
break;
}
break;
case SkFontHost::kNONE_LCDOrder:
break;
}
// Premultiplied alpha is very fragile.
a = a > r ? a : r;
a = a > g ? a : g;
a = a > b ? a : b;
*dst = SkPackARGB32(a, r, g, b);
}
src_row += h * row_words;
dst_row += result.rowBytes() / 4;
}
result.setAlphaType(img.alphaType());
return result;
#else
return SkBitmap();
#endif // OS_POSIX && !OS_MACOSX && !defined(OS_ANDROID)
}
// Returns the icon to be displayed in the window.
SkBitmap WidgetDelegate::GetWindowIcon()
{
return SkBitmap();
}
void ImageButton::SetImage(ButtonState aState, const SkBitmap* anImage)
{
images_[aState] = anImage ? *anImage : SkBitmap();
PreferredSizeChanged();
}
Menu* Menu::AddSubMenu(int index, int item_id, const std::wstring& label)
{
return AddSubMenuWithIcon(index, item_id, label, SkBitmap());
}
// static
SkBitmap ImageOperations::ResizeBasic(const SkBitmap& source,
ResizeMethod method,
int dest_width, int dest_height,
const SkIRect& dest_subset)
{
// 确保枚举值合法.
SkASSERT(((RESIZE_FIRST_QUALITY_METHOD<=method) &&
(method<=RESIZE_LAST_QUALITY_METHOD)) ||
((RESIZE_FIRST_ALGORITHM_METHOD<=method) &&
(method<=RESIZE_LAST_ALGORITHM_METHOD)));
// 用于计算函数执行时间, 方便查看是否有问题.
base::TimeTicks resize_start = base::TimeTicks::Now();
SkIRect dest = { 0, 0, dest_width, dest_height };
DCHECK(dest.contains(dest_subset)) <<
"The supplied subset does not fall within the destination image.";
// 如果源和目的大小都是0(0*0 0*N N*0), 返回一个空位图.
if(source.width()<1 || source.height()<1 ||
dest_width<1 || dest_height<1)
{
return SkBitmap();
}
method = ResizeMethodToAlgorithmMethod(method);
// Check that we deal with an "algorithm methods" from this point onward.
SkASSERT((ImageOperations::RESIZE_FIRST_ALGORITHM_METHOD<=method) &&
(method<=ImageOperations::RESIZE_LAST_ALGORITHM_METHOD));
SkAutoLockPixels locker(source);
ResizeFilter filter(method, source.width(), source.height(),
dest_width, dest_height, dest_subset);
// Get a source bitmap encompassing this touched area. We construct the
// offsets and row strides such that it looks like a new bitmap, while
// referring to the old data.
const uint8* source_subset =
reinterpret_cast<const uint8*>(source.getPixels());
// Convolve into the result.
base::CPU cpu;
SkBitmap result;
result.setConfig(SkBitmap::kARGB_8888_Config,
dest_subset.width(), dest_subset.height());
result.allocPixels();
BGRAConvolve2D(source_subset, static_cast<int>(source.rowBytes()),
!source.isOpaque(), filter.x_filter(), filter.y_filter(),
static_cast<int>(result.rowBytes()),
static_cast<unsigned char*>(result.getPixels()),
cpu.has_sse2());
// Preserve the "opaque" flag for use as an optimization later.
result.setIsOpaque(source.isOpaque());
base::TimeDelta delta = base::TimeTicks::Now() - resize_start;
UMA_HISTOGRAM_TIMES("Image.ResampleMS", delta);
return result;
}
