/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkCodec.h"
#include "SkCodecPriv.h"
#include "SkColorSpacePriv.h"
#include "SkColorData.h"
#include "SkData.h"
#include "SkJpegCodec.h"
#include "SkMakeUnique.h"
#include "SkMutex.h"
#include "SkRawCodec.h"
#include "SkRefCnt.h"
#include "SkStream.h"
#include "SkStreamPriv.h"
#include "SkTArray.h"
#include "SkTaskGroup.h"
#include "SkTemplates.h"
#include "SkTypes.h"
#include "dng_area_task.h"
#include "dng_color_space.h"
#include "dng_errors.h"
#include "dng_exceptions.h"
#include "dng_host.h"
#include "dng_info.h"
#include "dng_memory.h"
#include "dng_render.h"
#include "dng_stream.h"
#include "src/piex.h"
#include <cmath> // for std::round,floor,ceil
#include <limits>
namespace {
// Caluclates the number of tiles of tile_size that fit into the area in vertical and horizontal
// directions.
dng_point num_tiles_in_area(const dng_point &areaSize,
const dng_point_real64 &tileSize) {
// FIXME: Add a ceil_div() helper in SkCodecPriv.h
return dng_point(static_cast<int32>((areaSize.v + tileSize.v - 1) / tileSize.v),
static_cast<int32>((areaSize.h + tileSize.h - 1) / tileSize.h));
}
int num_tasks_required(const dng_point& tilesInTask,
const dng_point& tilesInArea) {
return ((tilesInArea.v + tilesInTask.v - 1) / tilesInTask.v) *
((tilesInArea.h + tilesInTask.h - 1) / tilesInTask.h);
}
// Calculate the number of tiles to process per task, taking into account the maximum number of
// tasks. It prefers to increase horizontally for better locality of reference.
dng_point num_tiles_per_task(const int maxTasks,
const dng_point &tilesInArea) {
dng_point tilesInTask = {1, 1};
while (num_tasks_required(tilesInTask, tilesInArea) > maxTasks) {
if (tilesInTask.h < tilesInArea.h) {
++tilesInTask.h;
} else if (tilesInTask.v < tilesInArea.v) {
++tilesInTask.v;
} else {
ThrowProgramError("num_tiles_per_task calculation is wrong.");
}
}
return tilesInTask;
}
std::vector<dng_rect> compute_task_areas(const int maxTasks, const dng_rect& area,
const dng_point& tileSize) {
std::vector<dng_rect> taskAreas;
const dng_point tilesInArea = num_tiles_in_area(area.Size(), tileSize);
const dng_point tilesPerTask = num_tiles_per_task(maxTasks, tilesInArea);
const dng_point taskAreaSize = {tilesPerTask.v * tileSize.v,
tilesPerTask.h * tileSize.h};
for (int v = 0; v < tilesInArea.v; v += tilesPerTask.v) {
for (int h = 0; h < tilesInArea.h; h += tilesPerTask.h) {
dng_rect taskArea;
taskArea.t = area.t + v * tileSize.v;
taskArea.l = area.l + h * tileSize.h;
taskArea.b = Min_int32(taskArea.t + taskAreaSize.v, area.b);
taskArea.r = Min_int32(taskArea.l + taskAreaSize.h, area.r);
taskAreas.push_back(taskArea);
}
}
return taskAreas;
}
class SkDngHost : public dng_host {
public:
explicit SkDngHost(dng_memory_allocator* allocater) : dng_host(allocater) {}
void PerformAreaTask(dng_area_task& task, const dng_rect& area) override {
SkTaskGroup taskGroup;
// tileSize is typically 256x256
const dng_point tileSize(task.FindTileSize(area));
const std::vector<dng_rect> taskAreas = compute_task_areas(this->PerformAreaTaskThreads(),
area, tileSize);
const int numTasks = static_cast<int>(taskAreas.size());
SkMutex mutex;
SkTArray<dng_exception> exceptions;
task.Start(numTasks, tileSize, &Allocator(), Sniffer());
for (int taskIndex = 0; taskIndex < numTasks; ++taskIndex) {
taskGroup.add([&mutex, &exceptions, &task, this, taskIndex, taskAreas, tileSize] {
try {
task.ProcessOnThread(taskIndex, taskAreas[taskIndex], tileSize, this->Sniffer());
} catch (dng_exception& exception) {
SkAutoMutexAcquire lock(mutex);
exceptions.push_back(exception);
} catch (...) {
SkAutoMutexAcquire lock(mutex);
exceptions.push_back(dng_exception(dng_error_unknown));
}
});
}
taskGroup.wait();
task.Finish(numTasks);
// We only re-throw the first exception.
if (!exceptions.empty()) {
Throw_dng_error(exceptions.front().ErrorCode(), nullptr, nullptr);
}
}
uint32 PerformAreaTaskThreads() override {
#ifdef SK_BUILD_FOR_ANDROID
// Only use 1 thread. DNGs with the warp effect require a lot of memory,
// and the amount of memory required scales linearly with the number of
// threads. The sample used in CTS requires over 500 MB, so even two
// threads is significantly expensive. There is no good way to tell
// whether the image has the warp effect.
return 1;
#else
return kMaxMPThreads;
#endif
}
private:
typedef dng_host INHERITED;
};
// T must be unsigned type.
template <class T>
bool safe_add_to_size_t(T arg1, T arg2, size_t* result) {
SkASSERT(arg1 >= 0);
SkASSERT(arg2 >= 0);
if (arg1 >= 0 && arg2 <= std::numeric_limits<T>::max() - arg1) {
T sum = arg1 + arg2;
if (sum <= std::numeric_limits<size_t>::max()) {
*result = static_cast<size_t>(sum);
return true;
}
}
return false;
}
bool is_asset_stream(const SkStream& stream) {
return stream.hasLength() && stream.hasPosition();
}
} // namespace
class SkRawStream {
public:
virtual ~SkRawStream() {}
/*
* Gets the length of the stream. Depending on the type of stream, this may require reading to
* the end of the stream.
*/
virtual uint64 getLength() = 0;
virtual bool read(void* data, size_t offset, size_t length) = 0;
/*
* Creates an SkMemoryStream from the offset with size.
* Note: for performance reason, this function is destructive to the SkRawStream. One should
* abandon current object after the function call.
*/
virtual std::unique_ptr<SkMemoryStream> transferBuffer(size_t offset, size_t size) = 0;
};
class SkRawLimitedDynamicMemoryWStream : public SkDynamicMemoryWStream {
public:
~SkRawLimitedDynamicMemoryWStream() override {}
bool write(const void* buffer, size_t size) override {
size_t newSize;
if (!safe_add_to_size_t(this->bytesWritten(), size, &newSize) ||
newSize > kMaxStreamSize)
{
SkCodecPrintf("Error: Stream size exceeds the limit.\n");
return false;
}
return this->INHERITED::write(buffer, size);
}
private:
// Most of valid RAW images will not be larger than 100MB. This limit is helpful to avoid
// streaming too large data chunk. We can always adjust the limit here if we need.
const size_t kMaxStreamSize = 100 * 1024 * 1024; // 100MB
typedef SkDynamicMemoryWStream INHERITED;
};
// Note: the maximum buffer size is 100MB (limited by SkRawLimitedDynamicMemoryWStream).
class SkRawBufferedStream : public SkRawStream {
public:
explicit SkRawBufferedStream(std::unique_ptr<SkStream> stream)
: fStream(std::move(stream))
, fWholeStreamRead(false)
{
// Only use SkRawBufferedStream when the stream is not an asset stream.
SkASSERT(!is_asset_stream(*fStream));
}
~SkRawBufferedStream() override {}
uint64 getLength() override {
if (!this->bufferMoreData(kReadToEnd)) { // read whole stream
ThrowReadFile();
}
return fStreamBuffer.bytesWritten();
}
bool read(void* data, size_t offset, size_t length) override {
if (length == 0) {
return true;
}
size_t sum;
if (!safe_add_to_size_t(offset, length, &sum)) {
return false;
}
return this->bufferMoreData(sum) && fStreamBuffer.read(data, offset, length);
}
std::unique_ptr<SkMemoryStream> transferBuffer(size_t offset, size_t size) override {
sk_sp<SkData> data(SkData::MakeUninitialized(size));
if (offset > fStreamBuffer.bytesWritten()) {
// If the offset is not buffered, read from fStream directly and skip the buffering.
const size_t skipLength = offset - fStreamBuffer.bytesWritten();
if (fStream->skip(skipLength) != skipLength) {
return nullptr;
}
const size_t bytesRead = fStream->read(data->writable_data(), size);
if (bytesRead < size) {
data = SkData::MakeSubset(data.get(), 0, bytesRead);
}
} else {
const size_t alreadyBuffered = SkTMin(fStreamBuffer.bytesWritten() - offset, size);
if (alreadyBuffered > 0 &&
!fStreamBuffer.read(data->writable_data(), offset, alreadyBuffered)) {
return nullptr;
}
const size_t remaining = size - alreadyBuffered;
if (remaining) {
auto* dst = static_cast<uint8_t*>(data->writable_data()) + alreadyBuffered;
const size_t bytesRead = fStream->read(dst, remaining);
size_t newSize;
if (bytesRead < remaining) {
if (!safe_add_to_size_t(alreadyBuffered, bytesRead, &newSize)) {
return nullptr;
}
data = SkData::MakeSubset(data.get(), 0, newSize);
}
}
}
return SkMemoryStream::Make(data);
}
private:
// Note: if the newSize == kReadToEnd (0), this function will read to the end of stream.
bool bufferMoreData(size_t newSize) {
if (newSize == kReadToEnd) {
if (fWholeStreamRead) { // already read-to-end.
return true;
}
// TODO: optimize for the special case when the input is SkMemoryStream.
return SkStreamCopy(&fStreamBuffer, fStream.get());
}
if (newSize <= fStreamBuffer.bytesWritten()) { // already buffered to newSize
return true;
}
if (fWholeStreamRead) { // newSize is larger than the whole stream.
return false;
}
// Try to read at least 8192 bytes to avoid to many small reads.
const size_t kMinSizeToRead = 8192;
const size_t sizeRequested = newSize - fStreamBuffer.bytesWritten();
const size_t sizeToRead = SkTMax(kMinSizeToRead, sizeRequested);
SkAutoSTMalloc<kMinSizeToRead, uint8> tempBuffer(sizeToRead);
const size_t bytesRead = fStream->read(tempBuffer.get(), sizeToRead);
if (bytesRead < sizeRequested) {
return false;
}
return fStreamBuffer.write(tempBuffer.get(), bytesRead);
}
std::unique_ptr<SkStream> fStream;
bool fWholeStreamRead;
// Use a size-limited stream to avoid holding too huge buffer.
SkRawLimitedDynamicMemoryWStream fStreamBuffer;
const size_t kReadToEnd = 0;
};
class SkRawAssetStream : public SkRawStream {
public:
explicit SkRawAssetStream(std::unique_ptr<SkStream> stream)
: fStream(std::move(stream))
{
// Only use SkRawAssetStream when the stream is an asset stream.
SkASSERT(is_asset_stream(*fStream));
}
~SkRawAssetStream() override {}
uint64 getLength() override {
return fStream->getLength();
}
bool read(void* data, size_t offset, size_t length) override {
if (length == 0) {
return true;
}
size_t sum;
if (!safe_add_to_size_t(offset, length, &sum)) {
return false;
}
return fStream->seek(offset) && (fStream->read(data, length) == length);
}
std::unique_ptr<SkMemoryStream> transferBuffer(size_t offset, size_t size) override {
if (fStream->getLength() < offset) {
return nullptr;
}
size_t sum;
if (!safe_add_to_size_t(offset, size, &sum)) {
return nullptr;
}
// This will allow read less than the requested "size", because the JPEG codec wants to
// handle also a partial JPEG file.
const size_t bytesToRead = SkTMin(sum, fStream->getLength()) - offset;
if (bytesToRead == 0) {
return nullptr;
}
if (fStream->getMemoryBase()) { // directly copy if getMemoryBase() is available.
sk_sp<SkData> data(SkData::MakeWithCopy(
static_cast<const uint8_t*>(fStream->getMemoryBase()) + offset, bytesToRead));
fStream.reset();
return SkMemoryStream::Make(data);
} else {
sk_sp<SkData> data(SkData::MakeUninitialized(bytesToRead));
if (!fStream->seek(offset)) {
return nullptr;
}
const size_t bytesRead = fStream->read(data->writable_data(), bytesToRead);
if (bytesRead < bytesToRead) {
data = SkData::MakeSubset(data.get(), 0, bytesRead);
}
return SkMemoryStream::Make(data);
}
}
private:
std::unique_ptr<SkStream> fStream;
};
class SkPiexStream : public ::piex::StreamInterface {
public:
// Will NOT take the ownership of the stream.
explicit SkPiexStream(SkRawStream* stream) : fStream(stream) {}
~SkPiexStream() override {}
::piex::Error GetData(const size_t offset, const size_t length,
uint8* data) override {
return fStream->read(static_cast<void*>(data), offset, length) ?
::piex::Error::kOk : ::piex::Error::kFail;
}
private:
SkRawStream* fStream;
};
class SkDngStream : public dng_stream {
public:
// Will NOT take the ownership of the stream.
SkDngStream(SkRawStream* stream) : fStream(stream) {}
~SkDngStream() override {}
uint64 DoGetLength() override { return fStream->getLength(); }
void DoRead(void* data, uint32 count, uint64 offset) override {
size_t sum;
if (!safe_add_to_size_t(static_cast<uint64>(count), offset, &sum) ||
!fStream->read(data, static_cast<size_t>(offset), static_cast<size_t>(count))) {
ThrowReadFile();
}
}
private:
SkRawStream* fStream;
};
class SkDngImage {
public:
/*
* Initializes the object with the information from Piex in a first attempt. This way it can
* save time and storage to obtain the DNG dimensions and color filter array (CFA) pattern
* which is essential for the demosaicing of the sensor image.
* Note: this will take the ownership of the stream.
*/
static SkDngImage* NewFromStream(SkRawStream* stream) {
std::unique_ptr<SkDngImage> dngImage(new SkDngImage(stream));
#if defined(IS_FUZZING_WITH_LIBFUZZER)
// Libfuzzer easily runs out of memory after here. To avoid that
// We just pretend all streams are invalid. Our AFL-fuzzer
// should still exercise this code; it's more resistant to OOM.
return nullptr;
#endif
if (!dngImage->initFromPiex() && !dngImage->readDng()) {
return nullptr;
}
return dngImage.release();
}
/*
* Renders the DNG image to the size. The DNG SDK only allows scaling close to integer factors
* down to 80 pixels on the short edge. The rendered image will be close to the specified size,
* but there is no guarantee that any of the edges will match the requested size. E.g.
* 100% size: 4000 x 3000
* requested size: 1600 x 1200
* returned size could be: 2000 x 1500
*/
dng_image* render(int width, int height) {
if (!fHost || !fInfo || !fNegative || !fDngStream) {
if (!this->readDng()) {
return nullptr;
}
}
// DNG SDK preserves the aspect ratio, so it only needs to know the longer dimension.
const int preferredSize = SkTMax(width, height);
try {
// render() takes ownership of fHost, fInfo, fNegative and fDngStream when available.
std::unique_ptr<dng_host> host(fHost.release());
std::unique_ptr<dng_info> info(fInfo.release());
std::unique_ptr<dng_negative> negative(fNegative.release());
std::unique_ptr<dng_stream> dngStream(fDngStream.release());
host->SetPreferredSize(preferredSize);
host->ValidateSizes();
negative->ReadStage1Image(*host, *dngStream, *info);
if (info->fMaskIndex != -1) {
negative->ReadTransparencyMask(*host, *dngStream, *info);
}
negative->ValidateRawImageDigest(*host);
if (negative->IsDamaged()) {
return nullptr;
}
const int32 kMosaicPlane = -1;
negative->BuildStage2Image(*host);
negative->BuildStage3Image(*host, kMosaicPlane);
dng_render render(*host, *negative);
render.SetFinalSpace(dng_space_sRGB::Get());
render.SetFinalPixelType(ttByte);
dng_point stage3_size = negative->Stage3Image()->Size();
render.SetMaximumSize(SkTMax(stage3_size.h, stage3_size.v));
return render.Render();
} catch (...) {
return nullptr;
}
}
int width() const {
return fWidth;
}
int height() const {
return fHeight;
}
bool isScalable() const {
return fIsScalable;
}
bool isXtransImage() const {
return fIsXtransImage;
}
// Quick check if the image contains a valid TIFF header as requested by DNG format.
// Does not affect ownership of stream.
static bool IsTiffHeaderValid(SkRawStream* stream) {
const size_t kHeaderSize = 4;
unsigned char header[kHeaderSize];
if (!stream->read(header, 0 /* offset */, kHeaderSize)) {
return false;
}
// Check if the header is valid (endian info and magic number "42").
bool littleEndian;
if (!is_valid_endian_marker(header, &littleEndian)) {
return false;
}
return 0x2A == get_endian_short(header + 2, littleEndian);
}
private:
bool init(int width, int height, const dng_point& cfaPatternSize) {
fWidth = width;
fHeight = height;
// The DNG SDK scales only during demosaicing, so scaling is only possible when
// a mosaic info is available.
fIsScalable = cfaPatternSize.v != 0 && cfaPatternSize.h != 0;
fIsXtransImage = fIsScalable ? (cfaPatternSize.v == 6 && cfaPatternSize.h == 6) : false;
return width > 0 && height > 0;
}
bool initFromPiex() {
// Does not take the ownership of rawStream.
SkPiexStream piexStream(fStream.get());
::piex::PreviewImageData imageData;
if (::piex::IsRaw(&piexStream)
&& ::piex::GetPreviewImageData(&piexStream, &imageData) == ::piex::Error::kOk)
{
dng_point cfaPatternSize(imageData.cfa_pattern_dim[1], imageData.cfa_pattern_dim[0]);
return this->init(static_cast<int>(imageData.full_width),
static_cast<int>(imageData.full_height), cfaPatternSize);
}
return false;
}
bool readDng() {
try {
// Due to the limit of DNG SDK, we need to reset host and info.
fHost.reset(new SkDngHost(&fAllocator));
fInfo.reset(new dng_info);
fDngStream.reset(new SkDngStream(fStream.get()));
fHost->ValidateSizes();
fInfo->Parse(*fHost, *fDngStream);
fInfo->PostParse(*fHost);
if (!fInfo->IsValidDNG()) {
return false;
}
fNegative.reset(fHost->Make_dng_negative());
fNegative->Parse(*fHost, *fDngStream, *fInfo);
fNegative->PostParse(*fHost, *fDngStream, *fInfo);
fNegative->SynchronizeMetadata();
dng_point cfaPatternSize(0, 0);
if (fNegative->GetMosaicInfo() != nullptr) {
cfaPatternSize = fNegative->GetMosaicInfo()->fCFAPatternSize;
}
return this->init(static_cast<int>(fNegative->DefaultCropSizeH().As_real64()),
static_cast<int>(fNegative->DefaultCropSizeV().As_real64()),
cfaPatternSize);
} catch (...) {
return false;
}
}
SkDngImage(SkRawStream* stream)
: fStream(stream)
{}
dng_memory_allocator fAllocator;
std::unique_ptr<SkRawStream> fStream;
std::unique_ptr<dng_host> fHost;
std::unique_ptr<dng_info> fInfo;
std::unique_ptr<dng_negative> fNegative;
std::unique_ptr<dng_stream> fDngStream;
int fWidth;
int fHeight;
bool fIsScalable;
bool fIsXtransImage;
};
/*
* Tries to handle the image with PIEX. If PIEX returns kOk and finds the preview image, create a
* SkJpegCodec. If PIEX returns kFail, then the file is invalid, return nullptr. In other cases,
* fallback to create SkRawCodec for DNG images.
*/
std::unique_ptr<SkCodec> SkRawCodec::MakeFromStream(std::unique_ptr<SkStream> stream,
Result* result) {
std::unique_ptr<SkRawStream> rawStream;
if (is_asset_stream(*stream)) {
rawStream.reset(new SkRawAssetStream(std::move(stream)));
} else {
rawStream.reset(new SkRawBufferedStream(std::move(stream)));
}
// Does not take the ownership of rawStream.
SkPiexStream piexStream(rawStream.get());
::piex::PreviewImageData imageData;
if (::piex::IsRaw(&piexStream)) {
::piex::Error error = ::piex::GetPreviewImageData(&piexStream, &imageData);
if (error == ::piex::Error::kFail) {
*result = kInvalidInput;
return nullptr;
}
std::unique_ptr<SkEncodedInfo::ICCProfile> profile;
if (imageData.color_space == ::piex::PreviewImageData::kAdobeRgb) {
skcms_ICCProfile skcmsProfile;
skcms_Init(&skcmsProfile);
skcms_SetTransferFunction(&skcmsProfile, &SkNamedTransferFn::k2Dot2);
skcms_SetXYZD50(&skcmsProfile, &SkNamedGamut::kAdobeRGB);
profile = SkEncodedInfo::ICCProfile::Make(skcmsProfile);
}
// Theoretically PIEX can return JPEG compressed image or uncompressed RGB image. We only
// handle the JPEG compressed preview image here.
if (error == ::piex::Error::kOk && imageData.preview.length > 0 &&
imageData.preview.format == ::piex::Image::kJpegCompressed)
{
// transferBuffer() is destructive to the rawStream. Abandon the rawStream after this
// function call.
// FIXME: one may avoid the copy of memoryStream and use the buffered rawStream.
auto memoryStream = rawStream->transferBuffer(imageData.preview.offset,
imageData.preview.length);
if (!memoryStream) {
*result = kInvalidInput;
return nullptr;
}
return SkJpegCodec::MakeFromStream(std::move(memoryStream), result,
std::move(profile));
}
}
if (!SkDngImage::IsTiffHeaderValid(rawStream.get())) {
*result = kUnimplemented;
return nullptr;
}
// Takes the ownership of the rawStream.
std::unique_ptr<SkDngImage> dngImage(SkDngImage::NewFromStream(rawStream.release()));
if (!dngImage) {
*result = kInvalidInput;
return nullptr;
}
*result = kSuccess;
return std::unique_ptr<SkCodec>(new SkRawCodec(dngImage.release()));
}
SkCodec::Result SkRawCodec::onGetPixels(const SkImageInfo& dstInfo, void* dst,
size_t dstRowBytes, const Options& options,
int* rowsDecoded) {
const int width = dstInfo.width();
const int height = dstInfo.height();
std::unique_ptr<dng_image> image(fDngImage->render(width, height));
if (!image) {
return kInvalidInput;
}
// Because the DNG SDK can not guarantee to render to requested size, we allow a small
// difference. Only the overlapping region will be converted.
const float maxDiffRatio = 1.03f;
const dng_point& imageSize = image->Size();
if (imageSize.h / (float) width > maxDiffRatio || imageSize.h < width ||
imageSize.v / (float) height > maxDiffRatio || imageSize.v < height) {
return SkCodec::kInvalidScale;
}
void* dstRow = dst;
SkAutoTMalloc<uint8_t> srcRow(width * 3);
dng_pixel_buffer buffer;
buffer.fData = &srcRow[0];
buffer.fPlane = 0;
buffer.fPlanes = 3;
buffer.fColStep = buffer.fPlanes;
buffer.fPlaneStep = 1;
buffer.fPixelType = ttByte;
buffer.fPixelSize = sizeof(uint8_t);
buffer.fRowStep = width * 3;
constexpr auto srcFormat = skcms_PixelFormat_RGB_888;
skcms_PixelFormat dstFormat;
if (!sk_select_xform_format(dstInfo.colorType(), false, &dstFormat)) {
return kInvalidConversion;
}
const skcms_ICCProfile* const srcProfile = this->getEncodedInfo().profile();
skcms_ICCProfile dstProfileStorage;
const skcms_ICCProfile* dstProfile = nullptr;
if (auto cs = dstInfo.colorSpace()) {
cs->toProfile(&dstProfileStorage);
dstProfile = &dstProfileStorage;
}
for (int i = 0; i < height; ++i) {
buffer.fArea = dng_rect(i, 0, i + 1, width);
try {
image->Get(buffer, dng_image::edge_zero);
} catch (...) {
*rowsDecoded = i;
return kIncompleteInput;
}
if (!skcms_Transform(&srcRow[0], srcFormat, skcms_AlphaFormat_Unpremul, srcProfile,
dstRow, dstFormat, skcms_AlphaFormat_Unpremul, dstProfile,
dstInfo.width())) {
SkDebugf("failed to transform\n");
*rowsDecoded = i;
return kInternalError;
}
dstRow = SkTAddOffset<void>(dstRow, dstRowBytes);
}
return kSuccess;
}
SkISize SkRawCodec::onGetScaledDimensions(float desiredScale) const {
SkASSERT(desiredScale <= 1.f);
const SkISize dim = this->dimensions();
SkASSERT(dim.fWidth != 0 && dim.fHeight != 0);
if (!fDngImage->isScalable()) {
return dim;
}
// Limits the minimum size to be 80 on the short edge.
const float shortEdge = static_cast<float>(SkTMin(dim.fWidth, dim.fHeight));
if (desiredScale < 80.f / shortEdge) {
desiredScale = 80.f / shortEdge;
}
// For Xtrans images, the integer-factor scaling does not support the half-size scaling case
// (stronger downscalings are fine). In this case, returns the factor "3" scaling instead.
if (fDngImage->isXtransImage() && desiredScale > 1.f / 3.f && desiredScale < 1.f) {
desiredScale = 1.f / 3.f;
}
// Round to integer-factors.
const float finalScale = std::floor(1.f/ desiredScale);
return SkISize::Make(static_cast<int32_t>(std::floor(dim.fWidth / finalScale)),
static_cast<int32_t>(std::floor(dim.fHeight / finalScale)));
}
bool SkRawCodec::onDimensionsSupported(const SkISize& dim) {
const SkISize fullDim = this->dimensions();
const float fullShortEdge = static_cast<float>(SkTMin(fullDim.fWidth, fullDim.fHeight));
const float shortEdge = static_cast<float>(SkTMin(dim.fWidth, dim.fHeight));
SkISize sizeFloor = this->onGetScaledDimensions(1.f / std::floor(fullShortEdge / shortEdge));
SkISize sizeCeil = this->onGetScaledDimensions(1.f / std::ceil(fullShortEdge / shortEdge));
return sizeFloor == dim || sizeCeil == dim;
}
SkRawCodec::~SkRawCodec() {}
SkRawCodec::SkRawCodec(SkDngImage* dngImage)
: INHERITED(SkEncodedInfo::Make(dngImage->width(), dngImage->height(),
SkEncodedInfo::kRGB_Color,
SkEncodedInfo::kOpaque_Alpha, 8),
skcms_PixelFormat_RGBA_8888, nullptr)
, fDngImage(dngImage) {}