michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef ImageEncoder_h
michael@0: #define ImageEncoder_h
michael@0: 
michael@0: #include "imgIEncoder.h"
michael@0: #include "nsDOMFile.h"
michael@0: #include "nsError.h"
michael@0: #include "mozilla/dom/HTMLCanvasElementBinding.h"
michael@0: #include "nsLayoutUtils.h"
michael@0: #include "nsNetUtil.h"
michael@0: #include "nsSize.h"
michael@0: 
michael@0: class nsICanvasRenderingContextInternal;
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: class EncodingRunnable;
michael@0: 
michael@0: class ImageEncoder
michael@0: {
michael@0: public:
michael@0:   // Extracts data synchronously and gives you a stream containing the image
michael@0:   // represented by aContext. aType may change to "image/png" if we had to fall
michael@0:   // back to a PNG encoder. A return value of NS_OK implies successful data
michael@0:   // extraction. If there are any unrecognized custom parse options in
michael@0:   // aOptions, NS_ERROR_INVALID_ARG will be returned. When encountering this
michael@0:   // error it is usual to call this function again without any options at all.
michael@0:   static nsresult ExtractData(nsAString& aType,
michael@0:                               const nsAString& aOptions,
michael@0:                               const nsIntSize aSize,
michael@0:                               bool aUsePlaceholder,
michael@0:                               nsICanvasRenderingContextInternal* aContext,
michael@0:                               nsIInputStream** aStream);
michael@0: 
michael@0:   // Extracts data asynchronously. aType may change to "image/png" if we had to
michael@0:   // fall back to a PNG encoder. aOptions are the options to be passed to the
michael@0:   // encoder and aUsingCustomOptions specifies whether custom parse options were
michael@0:   // used (i.e. by using -moz-parse-options). If there are any unrecognized
michael@0:   // custom parse options, we fall back to the default values for the encoder
michael@0:   // without any options at all. A return value of NS_OK only implies
michael@0:   // successful dispatching of the extraction step to the encoding thread.
michael@0:   static nsresult ExtractDataAsync(nsAString& aType,
michael@0:                                    const nsAString& aOptions,
michael@0:                                    bool aUsingCustomOptions,
michael@0:                                    uint8_t* aImageBuffer,
michael@0:                                    int32_t aFormat,
michael@0:                                    const nsIntSize aSize,
michael@0:                                    bool aUsePlaceholder,
michael@0:                                    nsICanvasRenderingContextInternal* aContext,
michael@0:                                    nsIScriptContext* aScriptContext,
michael@0:                                    FileCallback& aCallback);
michael@0: 
michael@0:   // Gives you a stream containing the image represented by aImageBuffer.
michael@0:   // The format is given in aFormat, for example
michael@0:   // imgIEncoder::INPUT_FORMAT_HOSTARGB.
michael@0:   static nsresult GetInputStream(int32_t aWidth,
michael@0:                                  int32_t aHeight,
michael@0:                                  uint8_t* aImageBuffer,
michael@0:                                  int32_t aFormat,
michael@0:                                  imgIEncoder* aEncoder,
michael@0:                                  const char16_t* aEncoderOptions,
michael@0:                                  nsIInputStream** aStream);
michael@0: 
michael@0: private:
michael@0:   // When called asynchronously, aContext is null.
michael@0:   static nsresult
michael@0:   ExtractDataInternal(const nsAString& aType,
michael@0:                       const nsAString& aOptions,
michael@0:                       uint8_t* aImageBuffer,
michael@0:                       int32_t aFormat,
michael@0:                       const nsIntSize aSize,
michael@0:                       bool aUsePlaceholder,
michael@0:                       nsICanvasRenderingContextInternal* aContext,
michael@0:                       nsIInputStream** aStream,
michael@0:                       imgIEncoder* aEncoder);
michael@0: 
michael@0:   // Creates and returns an encoder instance of the type specified in aType.
michael@0:   // aType may change to "image/png" if no instance of the original type could
michael@0:   // be created and we had to fall back to a PNG encoder. A null return value
michael@0:   // should be interpreted as NS_IMAGELIB_ERROR_NO_ENCODER and aType is
michael@0:   // undefined in this case.
michael@0:   static already_AddRefed<imgIEncoder> GetImageEncoder(nsAString& aType);
michael@0: 
michael@0:   friend class EncodingRunnable;
michael@0: };
michael@0: 
michael@0: } // namespace dom
michael@0: } // namespace mozilla
michael@0: 
michael@0: #endif // ImageEncoder_h