image/decoders/nsJPEGDecoder.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   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/. */
   6
   7 #ifndef mozilla_image_decoders_nsJPEGDecoder_h
   8 #define mozilla_image_decoders_nsJPEGDecoder_h
   9
  10 #include "RasterImage.h"
  11 // On Windows systems, RasterImage.h brings in 'windows.h', which defines INT32.
  12 // But the jpeg decoder has its own definition of INT32. To avoid build issues,
  13 // we need to undefine the version from 'windows.h'.
  14 #undef INT32
  15
  16 #include "Decoder.h"
  17
  18 #include "nsIInputStream.h"
  19 #include "nsIPipe.h"
  20 #include "qcms.h"
  21
  22 extern "C" {
  23 #include "jpeglib.h"
  24 }
  25
  26 #include <setjmp.h>
  27
  28 namespace mozilla {
  29 namespace image {
  30
  31 typedef struct {
  32     struct jpeg_error_mgr pub;  // "public" fields for IJG library
  33     jmp_buf setjmp_buffer;      // For handling catastropic errors
  34 } decoder_error_mgr;
  35
  36 typedef enum {
  37     JPEG_HEADER,                          // Reading JFIF headers
  38     JPEG_START_DECOMPRESS,
  39     JPEG_DECOMPRESS_PROGRESSIVE,          // Output progressive pixels
  40     JPEG_DECOMPRESS_SEQUENTIAL,           // Output sequential pixels
  41     JPEG_DONE,
  42     JPEG_SINK_NON_JPEG_TRAILER,          // Some image files have a
  43                                          // non-JPEG trailer
  44     JPEG_ERROR
  45 } jstate;
  46
  47 class RasterImage;
  48 struct Orientation;
  49
  50 class nsJPEGDecoder : public Decoder
  51 {
  52 public:
  53   virtual ~nsJPEGDecoder();
  54
  55   virtual void SetSampleSize(int aSampleSize) override
  56   {
  57     mSampleSize = aSampleSize;
  58   }
  59
  60   virtual void InitInternal() override;
  61   virtual void WriteInternal(const char* aBuffer, uint32_t aCount) override;
  62   virtual void FinishInternal() override;
  63
  64   virtual Telemetry::ID SpeedHistogram() override;
  65   void NotifyDone();
  66
  67 protected:
  68   Orientation ReadOrientationFromEXIF();
  69   void OutputScanlines(bool* suspend);
  70
  71 private:
  72   friend class DecoderFactory;
  73
  74   // Decoders should only be instantiated via DecoderFactory.
  75   nsJPEGDecoder(RasterImage* aImage, Decoder::DecodeStyle aDecodeStyle);
  76
  77 public:
  78   struct jpeg_decompress_struct mInfo;
  79   struct jpeg_source_mgr mSourceMgr;
  80   decoder_error_mgr mErr;
  81   jstate mState;
  82
  83   uint32_t mBytesToSkip;
  84
  85   const JOCTET* mSegment;   // The current segment we are decoding from
  86   uint32_t mSegmentLen;     // amount of data in mSegment
  87
  88   JOCTET* mBackBuffer;
  89   uint32_t mBackBufferLen; // Offset of end of active backtrack data
  90   uint32_t mBackBufferSize; // size in bytes what mBackBuffer was created with
  91   uint32_t mBackBufferUnreadLen; // amount of data currently in mBackBuffer
  92
  93   JOCTET * mProfile;
  94   uint32_t mProfileLength;
  95
  96   qcms_profile* mInProfile;
  97   qcms_transform* mTransform;
  98
  99   bool mReading;
 100
 101   const Decoder::DecodeStyle mDecodeStyle;
 102
 103   uint32_t mCMSMode;
 104
 105   int mSampleSize;
 106 };
 107
 108 } // namespace image
 109 } // namespace mozilla
 110
 111 #endif // mozilla_image_decoders_nsJPEGDecoder_h