Line data    Source code

       1             : /* This Source Code Form is subject to the terms of the Mozilla Public
       2             :  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
       3             :  * You can obtain one at http://mozilla.org/MPL/2.0/. */
       4             : 
       5             : #ifndef YUV_STAMPER_H_
       6             : #define YUV_STAMPER_H_
       7             : 
       8             : #include "nptypes.h"
       9             : 
      10             : namespace mozilla {
      11             : 
      12             : class
      13             : YuvStamper {
      14             : public:
      15             :   bool WriteDigits(uint32_t value);
      16             : 
      17             :   template<typename T>
      18             :   static bool Write(uint32_t width, uint32_t height, uint32_t stride,
      19             :                     unsigned char *pYData, const T& value,
      20             :                     uint32_t x=0, uint32_t y=0)
      21             :   {
      22             :     YuvStamper stamper(pYData, width, height, stride,
      23             :                        x, y,
      24             :                        (sDigitWidth + sInterDigit) * sPixelSize,
      25             :                        (sDigitHeight + sInterLine) * sPixelSize);
      26             :     return stamper.WriteDigits(value);
      27             :   }
      28             : 
      29             :   static bool Encode(uint32_t width, uint32_t height, uint32_t stride,
      30             :                      unsigned char* pYData, unsigned char* pMsg, size_t msg_len,
      31             :                      uint32_t x = 0, uint32_t y = 0);
      32             : 
      33             :   static bool Decode(uint32_t width, uint32_t height, uint32_t stride,
      34             :                      unsigned char* pYData, unsigned char* pMsg, size_t msg_len,
      35             :                      uint32_t x = 0, uint32_t y = 0);
      36             : 
      37             :  private:
      38             :   YuvStamper(unsigned char* pYData,
      39             :              uint32_t width, uint32_t height, uint32_t stride,
      40             :              uint32_t x, uint32_t y,
      41             :              unsigned char symbol_width, unsigned char symbol_height);
      42             : 
      43             :   bool WriteDigit(unsigned char digit);
      44             :   void WritePixel(unsigned char* data, uint32_t x, uint32_t y);
      45             :   uint32_t Capacity();
      46             :   bool AdvanceCursor();
      47             :   bool WriteBit(bool one);
      48             :   bool Write8(unsigned char value);
      49             :   bool ReadBit(unsigned char &value);
      50             :   bool Read8(unsigned char &bit);
      51             : 
      52             :   const static unsigned char sPixelSize = 3;
      53             :   const static unsigned char sDigitWidth = 6;
      54             :   const static unsigned char sDigitHeight = 7;
      55             :   const static unsigned char sInterDigit = 1;
      56             :   const static unsigned char sInterLine = 1;
      57             :   const static uint32_t sBitSize = 4;
      58             :   const static uint32_t sBitThreshold = 60;
      59             :   const static unsigned char sYOn = 0x80;
      60             :   const static unsigned char sYOff = 0;
      61             :   const static unsigned char sLumaThreshold = 96;
      62             :   const static unsigned char sLumaMin = 16;
      63             :   const static unsigned char sLumaMax = 235;
      64             : 
      65             :   unsigned char* pYData;
      66             :   uint32_t mStride;
      67             :   uint32_t mWidth;
      68             :   uint32_t mHeight;
      69             :   unsigned char mSymbolWidth;
      70             :   unsigned char mSymbolHeight;
      71             : 
      72             :   struct Cursor {
      73           0 :     Cursor(uint32_t x, uint32_t y):
      74           0 :       x(x), y(y) {}
      75             :     uint32_t x;
      76             :     uint32_t y;
      77             :   } mCursor;
      78             : };
      79             : 
      80             : }
      81             : 
      82             : #endif
      83             :