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// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "third_party/blink/renderer/platform/image-encoders/image_encoder.h"
#include "base/notreached.h"
#include "build/build_config.h"
#include "skia/rusty_png_feature.h"
#if BUILDFLAG(IS_WIN)
#include <basetsd.h> // Included before jpeglib.h because of INT32 clash
#endif
#include <stdio.h> // Needed by jpeglib.h
#include "jpeglib.h" // for JPEG_MAX_DIMENSION
#include "third_party/libwebp/src/src/webp/encode.h" // for WEBP_MAX_DIMENSION
namespace blink {
bool ImageEncoder::Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkJpegEncoder::Options& options) {
VectorWStream dst_stream(dst);
return SkJpegEncoder::Encode(&dst_stream, src, options);
}
bool ImageEncoder::Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkPngEncoder::Options& options) {
VectorWStream dst_stream(dst);
return skia::EncodePng(&dst_stream, src, options);
}
bool ImageEncoder::Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
const SkWebpEncoder::Options& options) {
VectorWStream dst_stream(dst);
return SkWebpEncoder::Encode(&dst_stream, src, options);
}
bool ImageEncoder::Encode(Vector<unsigned char>* dst,
const SkPixmap& src,
ImageEncodingMimeType mime_type,
double quality) {
switch (mime_type) {
case kMimeTypeJpeg: {
SkJpegEncoder::Options options;
options.fQuality = ComputeJpegQuality(quality);
options.fAlphaOption = SkJpegEncoder::AlphaOption::kBlendOnBlack;
if (options.fQuality == 100) {
options.fDownsample = SkJpegEncoder::Downsample::k444;
}
return Encode(dst, src, options);
}
case kMimeTypeWebp: {
SkWebpEncoder::Options options = ComputeWebpOptions(quality);
return Encode(dst, src, options);
}
case kMimeTypePng: {
SkPngEncoder::Options options;
options.fFilterFlags = SkPngEncoder::FilterFlag::kSub;
options.fZLibLevel = 3;
return Encode(dst, src, options);
}
}
}
std::unique_ptr<ImageEncoder> ImageEncoder::Create(
Vector<unsigned char>* dst,
const SkPixmap& src,
const SkJpegEncoder::Options& options) {
std::unique_ptr<ImageEncoder> image_encoder(new ImageEncoder(dst));
image_encoder->encoder_ =
SkJpegEncoder::Make(&image_encoder->dst_, src, options);
if (!image_encoder->encoder_) {
return nullptr;
}
return image_encoder;
}
std::unique_ptr<ImageEncoder> ImageEncoder::Create(
Vector<unsigned char>* dst,
const SkPixmap& src,
const SkPngEncoder::Options& options) {
std::unique_ptr<ImageEncoder> image_encoder(new ImageEncoder(dst));
image_encoder->encoder_ =
skia::MakePngEncoder(&image_encoder->dst_, src, options);
if (!image_encoder->encoder_) {
return nullptr;
}
return image_encoder;
}
int ImageEncoder::MaxDimension(ImageEncodingMimeType mime_type) {
switch (mime_type) {
case kMimeTypePng:
return 65535;
case kMimeTypeJpeg:
return JPEG_MAX_DIMENSION;
case kMimeTypeWebp:
return WEBP_MAX_DIMENSION;
default:
NOTREACHED();
}
}
int ImageEncoder::ComputeJpegQuality(double quality) {
int compression_quality = 92; // Default value
if (0.0f <= quality && quality <= 1.0)
compression_quality = static_cast<int>(quality * 100 + 0.5);
return compression_quality;
}
SkWebpEncoder::Options ImageEncoder::ComputeWebpOptions(double quality) {
SkWebpEncoder::Options options;
if (quality == 1.0) {
// Choose a lossless encode. When performing a lossless encode, higher
// quality corresponds to slower encoding and smaller output size.
options.fCompression = SkWebpEncoder::Compression::kLossless;
options.fQuality = 75.0f;
} else {
options.fQuality = 80.0f; // Default value
if (0.0f <= quality && quality <= 1.0)
options.fQuality = quality * 100.0f;
}
return options;
}
} // namespace blink
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