src/base/pngwriter.hh

   1 /*
   2  * Copyright (c) 2017 ARM Limited
   3  * All rights reserved
   4  *
   5  * The license below extends only to copyright in the software and shall
   6  * not be construed as granting a license to any other intellectual
   7  * property including but not limited to intellectual property relating
   8  * to a hardware implementation of the functionality of the software
   9  * licensed hereunder.  You may use the software subject to the license
  10  * terms below provided that you ensure that this notice is replicated
  11  * unmodified and in its entirety in all distributions of the software,
  12  * modified or unmodified, in source code or in binary form.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 /**
  39  * @file Declaration of a class that writes a frame buffer to a png
  40  */
  41
  42 #ifndef __BASE_PNG_HH__
  43 #define __BASE_PNG_HH__
  44
  45 #include "base/compiler.hh"
  46 #include "base/framebuffer.hh"
  47 #include "base/imgwriter.hh"
  48
  49 /** Image writer implementing support for PNG */
  50 class PngWriter : public ImgWriter
  51 {
  52   public:
  53     /**
  54      * Create a png that takes data in a given mode & size and
  55      * outputs to an ostream.
  56      */
  57     PngWriter(const FrameBuffer *_fb)
  58       : ImgWriter(_fb)
  59     {}
  60
  61     ~PngWriter() {};
  62
  63     /**
  64      * Return Image format as a string
  65      *
  66      * @return img extension (e.g. .png for Png)
  67      */
  68     const char* getImgExtension() const override
  69     { return _imgExtension; }
  70
  71     /**
  72      * Write the frame buffer data into the provided ostream
  73      *
  74      * @param png stream to write to
  75      */
  76     void write(std::ostream &png) const override;
  77   private:
  78     /** Png Pixel type: not containing padding */
  79     struct PngPixel24 {
  80         PngPixel24 &operator=(const Pixel &rhs) {
  81             red = rhs.red;
  82             green = rhs.green;
  83             blue = rhs.blue;
  84
  85             return *this;
  86         }
  87         uint8_t red;
  88         uint8_t green;
  89         uint8_t blue;
  90     } M5_ATTR_PACKED;
  91
  92     /**
  93      * Handle to resources used by libpng:
  94      *   - png_struct: Structure holding write informations
  95      *   - png_info  : Structure holding image informations
  96      *
  97      * The class is automatically taking care of struct
  98      * allocation/deallocation
  99      */
 100     struct PngStructHandle;
 101
 102     typedef PngPixel24 PixelType;
 103
 104     static const char* _imgExtension;
 105 };
 106
 107 #endif // __BASE_PNG_HH__