skia2/include/android/SkBitmapRegionDecoder.h
Derek Sollenberger 2fbf1bc8c9 Add SK_API to APIs used by the android framework.
This CL enables us to set the default visibility of the symbols
on Android to hidden.  It is the intent that all of he SK_APIs
that have been added to /src directies should be removed as soon
as we can remove their callers within Android.

Bug: b/31971097
Change-Id: Ic787f94df0fb0c2b8d941aa7095a12b317c4b5de
Reviewed-on: https://skia-review.googlesource.com/49501
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Derek Sollenberger <djsollen@google.com>
2017-09-21 18:14:36 +00:00

93 lines
3.3 KiB
C++

/*
* 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 SkBitmapRegionDecoder_DEFINED
#define SkBitmapRegionDecoder_DEFINED
#include "SkBitmap.h"
#include "SkBRDAllocator.h"
#include "SkEncodedImageFormat.h"
#include "SkStream.h"
/*
* This class aims to provide an interface to test multiple implementations of
* SkBitmapRegionDecoder.
*/
class SK_API SkBitmapRegionDecoder {
public:
enum Strategy {
kAndroidCodec_Strategy, // Uses SkAndroidCodec for scaling and subsetting
};
/*
* @param data Refs the data while this object exists, unrefs on destruction
* @param strategy Strategy used for scaling and subsetting
* @return Tries to create an SkBitmapRegionDecoder, returns NULL on failure
*/
static SkBitmapRegionDecoder* Create(sk_sp<SkData>, Strategy strategy);
/*
* @param stream Takes ownership of the stream
* @param strategy Strategy used for scaling and subsetting
* @return Tries to create an SkBitmapRegionDecoder, returns NULL on failure
*/
static SkBitmapRegionDecoder* Create(
SkStreamRewindable* stream, Strategy strategy);
/*
* Decode a scaled region of the encoded image stream
*
* @param bitmap Container for decoded pixels. It is assumed that the pixels
* are initially unallocated and will be allocated by this function.
* @param allocator Allocator for the pixels. If this is NULL, the default
* allocator (HeapAllocator) will be used.
* @param desiredSubset Subset of the original image to decode.
* @param sampleSize An integer downscaling factor for the decode.
* @param colorType Preferred output colorType.
* New implementations should return NULL if they do not support
* decoding to this color type.
* The old kOriginal_Strategy will decode to a default color type
* if this color type is unsupported.
* @param requireUnpremul If the image is not opaque, we will use this to determine the
* alpha type to use.
* @param prefColorSpace If non-null and supported, this is the color space that we will
* decode into. Otherwise, we will choose a default.
*
*/
virtual bool decodeRegion(SkBitmap* bitmap, SkBRDAllocator* allocator,
const SkIRect& desiredSubset, int sampleSize,
SkColorType colorType, bool requireUnpremul,
sk_sp<SkColorSpace> prefColorSpace = nullptr) = 0;
virtual SkEncodedImageFormat getEncodedFormat() = 0;
virtual SkColorType computeOutputColorType(SkColorType requestedColorType) = 0;
virtual sk_sp<SkColorSpace> computeOutputColorSpace(SkColorType outputColorType,
sk_sp<SkColorSpace> prefColorSpace = nullptr) = 0;
int width() const { return fWidth; }
int height() const { return fHeight; }
virtual ~SkBitmapRegionDecoder() {}
protected:
SkBitmapRegionDecoder(int width, int height)
: fWidth(width)
, fHeight(height)
{}
private:
const int fWidth;
const int fHeight;
};
#endif