blob: 35e4f571d0d1aee61c9c9671a8d8e28a6655d3b7 [file] [log] [blame]
/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkSampledCodec_DEFINED
#define SkSampledCodec_DEFINED
#include "SkAndroidCodec.h"
#include "SkCodec.h"
/**
* This class implements the functionality of SkAndroidCodec. Scaling will
* be provided by sampling if it cannot be provided by fCodec.
*/
class SkSampledCodec : public SkAndroidCodec {
public:
explicit SkSampledCodec(SkCodec*);
virtual ~SkSampledCodec() {}
protected:
SkISize onGetSampledDimensions(int sampleSize) const override;
bool onGetSupportedSubset(SkIRect* desiredSubset) const override { return true; }
SkCodec::Result onGetAndroidPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
const AndroidOptions& options) override;
private:
/**
* Find the best way to account for native scaling.
*
* Return a size that fCodec can scale to, and adjust sampleSize to finish scaling.
*
* @param sampleSize As an input, the requested sample size.
* As an output, sampling needed after letting fCodec
* scale to the returned dimensions.
* @param nativeSampleSize Optional output parameter. Will be set to the
* effective sample size done by fCodec.
* @return SkISize The size that fCodec should scale to.
*/
SkISize accountForNativeScaling(int* sampleSize, int* nativeSampleSize = nullptr) const;
/**
* This fulfills the same contract as onGetAndroidPixels().
*
* We call this function from onGetAndroidPixels() if we have determined
* that fCodec does not support the requested scale, and we need to
* provide the scale by sampling.
*/
SkCodec::Result sampledDecode(const SkImageInfo& info, void* pixels, size_t rowBytes,
const AndroidOptions& options);
typedef SkAndroidCodec INHERITED;
};
#endif // SkSampledCodec_DEFINED