1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
10 #include "imgIEncoder.h"
12 #include "mozilla/dom/File.h"
13 #include "mozilla/dom/HTMLCanvasElementBinding.h"
14 #include "mozilla/UniquePtr.h"
17 class nsICanvasRenderingContextInternal
;
27 class EncodeCompleteCallback
;
28 class EncodingRunnable
;
29 class OffscreenCanvasDisplayHelper
;
33 // Extracts data synchronously and gives you a stream containing the image
34 // represented by aContext. aType may change to "image/png" if we had to fall
35 // back to a PNG encoder. A return value of NS_OK implies successful data
36 // extraction. If there are any unrecognized custom parse options in
37 // aOptions, NS_ERROR_INVALID_ARG will be returned. When encountering this
38 // error it is usual to call this function again without any options at all.
39 static nsresult
ExtractData(nsAString
& aType
, const nsAString
& aOptions
,
40 const nsIntSize aSize
, bool aUsePlaceholder
,
41 nsICanvasRenderingContextInternal
* aContext
,
42 OffscreenCanvasDisplayHelper
* aOffscreenDisplay
,
43 nsIInputStream
** aStream
);
45 // Extracts data asynchronously. aType may change to "image/png" if we had to
46 // fall back to a PNG encoder. aOptions are the options to be passed to the
47 // encoder and aUsingCustomOptions specifies whether custom parse options were
48 // used (i.e. by using -moz-parse-options). If there are any unrecognized
49 // custom parse options, we fall back to the default values for the encoder
50 // without any options at all. A return value of NS_OK only implies
51 // successful dispatching of the extraction step to the encoding thread.
52 // aEncodeCallback will be called on main thread when encoding process is
54 // Note: The callback has to set a valid parent for content for the generated
56 static nsresult
ExtractDataAsync(nsAString
& aType
, const nsAString
& aOptions
,
57 bool aUsingCustomOptions
,
58 UniquePtr
<uint8_t[]> aImageBuffer
,
59 int32_t aFormat
, const nsIntSize aSize
,
61 EncodeCompleteCallback
* aEncodeCallback
);
63 // Extract an Image asynchronously. Its function is same as ExtractDataAsync
64 // except for the parameters. aImage is the uncompressed data. aEncodeCallback
65 // will be called on main thread when encoding process is success.
66 // Note: The callback has to set a valid parent for content for the generated
68 static nsresult
ExtractDataFromLayersImageAsync(
69 nsAString
& aType
, const nsAString
& aOptions
, bool aUsingCustomOptions
,
70 layers::Image
* aImage
, bool aUsePlaceholder
,
71 EncodeCompleteCallback
* aEncodeCallback
);
73 // Gives you a stream containing the image represented by aImageBuffer.
74 // The format is given in aFormat, for example
75 // imgIEncoder::INPUT_FORMAT_HOSTARGB.
76 static nsresult
GetInputStream(int32_t aWidth
, int32_t aHeight
,
77 uint8_t* aImageBuffer
, int32_t aFormat
,
78 imgIEncoder
* aEncoder
,
79 const nsAString
& aEncoderOptions
,
80 nsIInputStream
** aStream
);
83 // When called asynchronously, aContext and aRenderer are null.
84 static nsresult
ExtractDataInternal(
85 const nsAString
& aType
, const nsAString
& aOptions
, uint8_t* aImageBuffer
,
86 int32_t aFormat
, const nsIntSize aSize
, bool aUsePlaceholder
,
87 layers::Image
* aImage
, nsICanvasRenderingContextInternal
* aContext
,
88 OffscreenCanvasDisplayHelper
* aOffscreenDisplay
, nsIInputStream
** aStream
,
89 imgIEncoder
* aEncoder
);
91 // Creates and returns an encoder instance of the type specified in aType.
92 // aType may change to "image/png" if no instance of the original type could
93 // be created and we had to fall back to a PNG encoder. A null return value
94 // should be interpreted as NS_IMAGELIB_ERROR_NO_ENCODER and aType is
95 // undefined in this case.
96 static already_AddRefed
<imgIEncoder
> GetImageEncoder(nsAString
& aType
);
98 friend class EncodingRunnable
;
99 friend class EncoderThreadPoolTerminator
;
103 * The callback interface of ExtractDataAsync and
104 * ExtractDataFromLayersImageAsync. ReceiveBlobImpl() is called on main thread
105 * when encoding is complete.
107 class EncodeCompleteCallback
{
109 NS_INLINE_DECL_THREADSAFE_REFCOUNTING(EncodeCompleteCallback
)
112 virtual nsresult
ReceiveBlobImpl(already_AddRefed
<BlobImpl
> aBlobImpl
) = 0;
114 // CanBeDeletedOnAnyThread is pure virtual, so that whoever extends this class
115 // needs to think how to handle cases like the owning DOM worker thread
117 virtual bool CanBeDeletedOnAnyThread() = 0;
120 virtual ~EncodeCompleteCallback() = default;
124 } // namespace mozilla
126 #endif // ImageEncoder_h