mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-26 06:11:37 +00:00
265e672179
# ignore-this-changeset --HG-- extra : amend_source : 4d301d3b0b8711c4692392aa76088ba7fd7d1022
302 lines
10 KiB
C++
302 lines
10 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
|
|
*
|
|
* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#include "Downscaler.h"
|
|
|
|
#include <algorithm>
|
|
#include <ctime>
|
|
#include "gfxPrefs.h"
|
|
#include "mozilla/gfx/2D.h"
|
|
|
|
using std::max;
|
|
using std::swap;
|
|
|
|
namespace mozilla {
|
|
|
|
using gfx::IntRect;
|
|
|
|
namespace image {
|
|
|
|
Downscaler::Downscaler(const nsIntSize& aTargetSize)
|
|
: mTargetSize(aTargetSize),
|
|
mOutputBuffer(nullptr),
|
|
mWindowCapacity(0),
|
|
mLinesInBuffer(0),
|
|
mPrevInvalidatedLine(0),
|
|
mCurrentOutLine(0),
|
|
mCurrentInLine(0),
|
|
mHasAlpha(true),
|
|
mFlipVertically(false) {
|
|
MOZ_ASSERT(mTargetSize.width > 0 && mTargetSize.height > 0,
|
|
"Invalid target size");
|
|
}
|
|
|
|
Downscaler::~Downscaler() { ReleaseWindow(); }
|
|
|
|
void Downscaler::ReleaseWindow() {
|
|
if (!mWindow) {
|
|
return;
|
|
}
|
|
|
|
for (int32_t i = 0; i < mWindowCapacity; ++i) {
|
|
delete[] mWindow[i];
|
|
}
|
|
|
|
mWindow = nullptr;
|
|
mWindowCapacity = 0;
|
|
}
|
|
|
|
nsresult Downscaler::BeginFrame(const nsIntSize& aOriginalSize,
|
|
const Maybe<nsIntRect>& aFrameRect,
|
|
uint8_t* aOutputBuffer, bool aHasAlpha,
|
|
bool aFlipVertically /* = false */) {
|
|
MOZ_ASSERT(aOutputBuffer);
|
|
MOZ_ASSERT(mTargetSize != aOriginalSize,
|
|
"Created a downscaler, but not downscaling?");
|
|
MOZ_ASSERT(mTargetSize.width <= aOriginalSize.width,
|
|
"Created a downscaler, but width is larger");
|
|
MOZ_ASSERT(mTargetSize.height <= aOriginalSize.height,
|
|
"Created a downscaler, but height is larger");
|
|
MOZ_ASSERT(aOriginalSize.width > 0 && aOriginalSize.height > 0,
|
|
"Invalid original size");
|
|
|
|
// Only downscale from reasonable sizes to avoid using too much memory/cpu
|
|
// downscaling and decoding. 1 << 20 == 1,048,576 seems a reasonable limit.
|
|
if (aOriginalSize.width > (1 << 20) || aOriginalSize.height > (1 << 20)) {
|
|
NS_WARNING("Trying to downscale image frame that is too large");
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
|
|
mFrameRect = aFrameRect.valueOr(nsIntRect(nsIntPoint(), aOriginalSize));
|
|
MOZ_ASSERT(mFrameRect.X() >= 0 && mFrameRect.Y() >= 0 &&
|
|
mFrameRect.Width() >= 0 && mFrameRect.Height() >= 0,
|
|
"Frame rect must have non-negative components");
|
|
MOZ_ASSERT(nsIntRect(0, 0, aOriginalSize.width, aOriginalSize.height)
|
|
.Contains(mFrameRect),
|
|
"Frame rect must fit inside image");
|
|
MOZ_ASSERT_IF(!nsIntRect(0, 0, aOriginalSize.width, aOriginalSize.height)
|
|
.IsEqualEdges(mFrameRect),
|
|
aHasAlpha);
|
|
|
|
mOriginalSize = aOriginalSize;
|
|
mScale = gfxSize(double(mOriginalSize.width) / mTargetSize.width,
|
|
double(mOriginalSize.height) / mTargetSize.height);
|
|
mOutputBuffer = aOutputBuffer;
|
|
mHasAlpha = aHasAlpha;
|
|
mFlipVertically = aFlipVertically;
|
|
|
|
ReleaseWindow();
|
|
|
|
auto resizeMethod = gfx::ConvolutionFilter::ResizeMethod::LANCZOS3;
|
|
if (!mXFilter.ComputeResizeFilter(resizeMethod, mOriginalSize.width,
|
|
mTargetSize.width) ||
|
|
!mYFilter.ComputeResizeFilter(resizeMethod, mOriginalSize.height,
|
|
mTargetSize.height)) {
|
|
NS_WARNING("Failed to compute filters for image downscaling");
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
|
|
// Allocate the buffer, which contains scanlines of the original image.
|
|
// pad to handle overreads by the simd code
|
|
size_t bufferLen = gfx::ConvolutionFilter::PadBytesForSIMD(
|
|
mOriginalSize.width * sizeof(uint32_t));
|
|
mRowBuffer.reset(new (fallible) uint8_t[bufferLen]);
|
|
if (MOZ_UNLIKELY(!mRowBuffer)) {
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
|
|
// Zero buffer to keep valgrind happy.
|
|
memset(mRowBuffer.get(), 0, bufferLen);
|
|
|
|
// Allocate the window, which contains horizontally downscaled scanlines. (We
|
|
// can store scanlines which are already downscale because our downscaling
|
|
// filter is separable.)
|
|
mWindowCapacity = mYFilter.MaxFilter();
|
|
mWindow.reset(new (fallible) uint8_t*[mWindowCapacity]);
|
|
if (MOZ_UNLIKELY(!mWindow)) {
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
|
|
bool anyAllocationFailed = false;
|
|
// pad to handle overreads by the simd code
|
|
const size_t rowSize = gfx::ConvolutionFilter::PadBytesForSIMD(
|
|
mTargetSize.width * sizeof(uint32_t));
|
|
for (int32_t i = 0; i < mWindowCapacity; ++i) {
|
|
mWindow[i] = new (fallible) uint8_t[rowSize];
|
|
anyAllocationFailed = anyAllocationFailed || mWindow[i] == nullptr;
|
|
}
|
|
|
|
if (MOZ_UNLIKELY(anyAllocationFailed)) {
|
|
// We intentionally iterate through the entire array even if an allocation
|
|
// fails, to ensure that all the pointers in it are either valid or nullptr.
|
|
// That in turn ensures that ReleaseWindow() can clean up correctly.
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
|
|
ResetForNextProgressivePass();
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
void Downscaler::SkipToRow(int32_t aRow) {
|
|
if (mCurrentInLine < aRow) {
|
|
ClearRow();
|
|
do {
|
|
CommitRow();
|
|
} while (mCurrentInLine < aRow);
|
|
}
|
|
}
|
|
|
|
void Downscaler::ResetForNextProgressivePass() {
|
|
mPrevInvalidatedLine = 0;
|
|
mCurrentOutLine = 0;
|
|
mCurrentInLine = 0;
|
|
mLinesInBuffer = 0;
|
|
|
|
if (mFrameRect.IsEmpty()) {
|
|
// Our frame rect is zero size; commit rows until the end of the image.
|
|
SkipToRow(mOriginalSize.height - 1);
|
|
} else {
|
|
// If we have a vertical offset, commit rows to shift us past it.
|
|
SkipToRow(mFrameRect.Y());
|
|
}
|
|
}
|
|
|
|
void Downscaler::ClearRestOfRow(uint32_t aStartingAtCol) {
|
|
MOZ_ASSERT(int64_t(aStartingAtCol) <= int64_t(mOriginalSize.width));
|
|
uint32_t bytesToClear =
|
|
(mOriginalSize.width - aStartingAtCol) * sizeof(uint32_t);
|
|
memset(mRowBuffer.get() + (aStartingAtCol * sizeof(uint32_t)), 0,
|
|
bytesToClear);
|
|
}
|
|
|
|
void Downscaler::CommitRow() {
|
|
MOZ_ASSERT(mOutputBuffer, "Should have a current frame");
|
|
MOZ_ASSERT(mCurrentInLine < mOriginalSize.height, "Past end of input");
|
|
|
|
if (mCurrentOutLine < mTargetSize.height) {
|
|
int32_t filterOffset = 0;
|
|
int32_t filterLength = 0;
|
|
mYFilter.GetFilterOffsetAndLength(mCurrentOutLine, &filterOffset,
|
|
&filterLength);
|
|
|
|
int32_t inLineToRead = filterOffset + mLinesInBuffer;
|
|
MOZ_ASSERT(mCurrentInLine <= inLineToRead, "Reading past end of input");
|
|
if (mCurrentInLine == inLineToRead) {
|
|
MOZ_RELEASE_ASSERT(mLinesInBuffer < mWindowCapacity,
|
|
"Need more rows than capacity!");
|
|
mXFilter.ConvolveHorizontally(mRowBuffer.get(), mWindow[mLinesInBuffer++],
|
|
mHasAlpha);
|
|
}
|
|
|
|
MOZ_ASSERT(mCurrentOutLine < mTargetSize.height,
|
|
"Writing past end of output");
|
|
|
|
while (mLinesInBuffer >= filterLength) {
|
|
DownscaleInputLine();
|
|
|
|
if (mCurrentOutLine == mTargetSize.height) {
|
|
break; // We're done.
|
|
}
|
|
|
|
mYFilter.GetFilterOffsetAndLength(mCurrentOutLine, &filterOffset,
|
|
&filterLength);
|
|
}
|
|
}
|
|
|
|
mCurrentInLine += 1;
|
|
|
|
// If we're at the end of the part of the original image that has data, commit
|
|
// rows to shift us to the end.
|
|
if (mCurrentInLine == (mFrameRect.Y() + mFrameRect.Height())) {
|
|
SkipToRow(mOriginalSize.height - 1);
|
|
}
|
|
}
|
|
|
|
bool Downscaler::HasInvalidation() const {
|
|
return mCurrentOutLine > mPrevInvalidatedLine;
|
|
}
|
|
|
|
DownscalerInvalidRect Downscaler::TakeInvalidRect() {
|
|
if (MOZ_UNLIKELY(!HasInvalidation())) {
|
|
return DownscalerInvalidRect();
|
|
}
|
|
|
|
DownscalerInvalidRect invalidRect;
|
|
|
|
// Compute the target size invalid rect.
|
|
if (mFlipVertically) {
|
|
// We need to flip it. This will implicitly flip the original size invalid
|
|
// rect, since we compute it by scaling this rect.
|
|
invalidRect.mTargetSizeRect =
|
|
IntRect(0, mTargetSize.height - mCurrentOutLine, mTargetSize.width,
|
|
mCurrentOutLine - mPrevInvalidatedLine);
|
|
} else {
|
|
invalidRect.mTargetSizeRect =
|
|
IntRect(0, mPrevInvalidatedLine, mTargetSize.width,
|
|
mCurrentOutLine - mPrevInvalidatedLine);
|
|
}
|
|
|
|
mPrevInvalidatedLine = mCurrentOutLine;
|
|
|
|
// Compute the original size invalid rect.
|
|
invalidRect.mOriginalSizeRect = invalidRect.mTargetSizeRect;
|
|
invalidRect.mOriginalSizeRect.ScaleRoundOut(mScale.width, mScale.height);
|
|
|
|
return invalidRect;
|
|
}
|
|
|
|
void Downscaler::DownscaleInputLine() {
|
|
MOZ_ASSERT(mOutputBuffer);
|
|
MOZ_ASSERT(mCurrentOutLine < mTargetSize.height,
|
|
"Writing past end of output");
|
|
|
|
int32_t filterOffset = 0;
|
|
int32_t filterLength = 0;
|
|
mYFilter.GetFilterOffsetAndLength(mCurrentOutLine, &filterOffset,
|
|
&filterLength);
|
|
|
|
int32_t currentOutLine = mFlipVertically
|
|
? mTargetSize.height - (mCurrentOutLine + 1)
|
|
: mCurrentOutLine;
|
|
MOZ_ASSERT(currentOutLine >= 0);
|
|
|
|
uint8_t* outputLine =
|
|
&mOutputBuffer[currentOutLine * mTargetSize.width * sizeof(uint32_t)];
|
|
mYFilter.ConvolveVertically(mWindow.get(), outputLine, mCurrentOutLine,
|
|
mXFilter.NumValues(), mHasAlpha);
|
|
|
|
mCurrentOutLine += 1;
|
|
|
|
if (mCurrentOutLine == mTargetSize.height) {
|
|
// We're done.
|
|
return;
|
|
}
|
|
|
|
int32_t newFilterOffset = 0;
|
|
int32_t newFilterLength = 0;
|
|
mYFilter.GetFilterOffsetAndLength(mCurrentOutLine, &newFilterOffset,
|
|
&newFilterLength);
|
|
|
|
int diff = newFilterOffset - filterOffset;
|
|
MOZ_ASSERT(diff >= 0, "Moving backwards in the filter?");
|
|
|
|
// Shift the buffer. We're just moving pointers here, so this is cheap.
|
|
mLinesInBuffer -= diff;
|
|
mLinesInBuffer = min(max(mLinesInBuffer, 0), mWindowCapacity);
|
|
|
|
// If we already have enough rows to satisfy the filter, there is no need
|
|
// to swap as we won't be writing more before the next convolution.
|
|
if (filterLength > mLinesInBuffer) {
|
|
for (int32_t i = 0; i < mLinesInBuffer; ++i) {
|
|
swap(mWindow[i], mWindow[filterLength - mLinesInBuffer + i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
} // namespace image
|
|
} // namespace mozilla
|