• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright 2007, The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef IMAGE_CODEC_BMPDECODERHELPER_H__
18 #define IMAGE_CODEC_BMPDECODERHELPER_H__
19 
20 ///////////////////////////////////////////////////////////////////////////////
21 // this section is my current "glue" between google3 code and android.
22 // will be fixed soon
23 
24 #include "SkTypes.h"
25 #include <limits.h>
26 #define DISALLOW_EVIL_CONSTRUCTORS(name)
27 #define CHECK(predicate)  SkASSERT(predicate)
28 typedef uint8_t uint8;
29 typedef uint32_t uint32;
30 
31 template <typename T> class scoped_array {
32 private:
33   T* ptr_;
34   scoped_array(scoped_array const&);
35   scoped_array& operator=(const scoped_array&);
36 
37 public:
ptr_(p)38   explicit scoped_array(T* p = 0) : ptr_(p) {}
~scoped_array()39   ~scoped_array() {
40     delete[] ptr_;
41   }
42 
43   void reset(T* p = 0) {
44     if (p != ptr_) {
45       delete[] ptr_;
46       ptr_ = p;
47     }
48   }
49 
50   T& operator[](int i) const {
51     return ptr_[i];
52   }
53 };
54 
55 ///////////////////////////////////////////////////////////////////////////////
56 
57 namespace image_codec {
58 
59 class BmpDecoderCallback {
60  public:
BmpDecoderCallback()61   BmpDecoderCallback() { }
~BmpDecoderCallback()62   virtual ~BmpDecoderCallback() {}
63 
64   /**
65    * This is called once for an image. It is passed the width and height and
66    * should return the address of a buffer that is large enough to store
67    * all of the resulting pixels (widht * height * 3 bytes). If it returns NULL,
68    * then the decoder will abort, but return true, as the caller has received
69    * valid dimensions.
70    */
71   virtual uint8* SetSize(int width, int height) = 0;
72 
73  private:
74   DISALLOW_EVIL_CONSTRUCTORS(BmpDecoderCallback);
75 };
76 
77 class BmpDecoderHelper {
78  public:
BmpDecoderHelper()79   BmpDecoderHelper() { }
~BmpDecoderHelper()80   ~BmpDecoderHelper() { }
81   bool DecodeImage(const char* data,
82                    int len,
83                    int max_pixels,
84                    BmpDecoderCallback* callback);
85 
86  private:
87   DISALLOW_EVIL_CONSTRUCTORS(BmpDecoderHelper);
88 
89   void DoRLEDecode();
90   void DoStandardDecode();
91   void PutPixel(int x, int y, uint8 col);
92 
93   int GetInt();
94   int GetShort();
95   uint8 GetByte();
96   int CalcShiftRight(uint32 mask);
97   int CalcShiftLeft(uint32 mask);
98 
99   const uint8* data_;
100   int pos_;
101   int len_;
102   int width_;
103   int height_;
104   int bpp_;
105   int pixelPad_;
106   int rowPad_;
107   scoped_array<uint8> colTab_;
108   uint32 redBits_;
109   uint32 greenBits_;
110   uint32 blueBits_;
111   int redShiftRight_;
112   int greenShiftRight_;
113   int blueShiftRight_;
114   int redShiftLeft_;
115   int greenShiftLeft_;
116   int blueShiftLeft_;
117   uint8* output_;
118   bool inverted_;
119 };
120 
121 } // namespace
122 
123 #endif
124