text: /*************************************************************************/
  /*  image_loader_jpegd.cpp                                               */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           GODOT ENGINE                                */
  /*                      https://godotengine.org                          */
  /*************************************************************************/
  /* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
  /* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md).   */
  /*                                                                       */
  /* Permission is hereby granted, free of charge, to any person obtaining */
  /* a copy of this software and associated documentation files (the       */
  /* "Software"), to deal in the Software without restriction, including   */
  /* without limitation the rights to use, copy, modify, merge, publish,   */
  /* distribute, sublicense, and/or sell copies of the Software, and to    */
  /* permit persons to whom the Software is furnished to do so, subject to */
  /* the following conditions:                                             */
  /*                                                                       */
  /* The above copyright notice and this permission notice shall be        */
  /* included in all copies or substantial portions of the Software.       */
  /*                                                                       */
  /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
  /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
  /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
  /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
  /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
  /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
  /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
  /*************************************************************************/
  
  #include "image_loader_jpegd.h"
  
  #include "core/image_data.h"
  #include "core/print_string.h"
  #include "core/os/file_access.h"
  #include "core/ustring.h"
  
  #include <jpgd.h>
  #include <cstring>
  
  Error jpeg_load_image_from_buffer(ImageData &p_image, const uint8_t *p_buffer, int p_buffer_len) {
  
      jpgd::jpeg_decoder_mem_stream mem_stream(p_buffer, p_buffer_len);
  
      jpgd::jpeg_decoder decoder(&mem_stream);
  
      if (decoder.get_error_code() != jpgd::JPGD_SUCCESS) {
          return ERR_CANT_OPEN;
      }
  
      const int image_width = decoder.get_width();
      const int image_height = decoder.get_height();
      const int comps = decoder.get_num_components();
      if (comps != 1 && comps != 3)
          return ERR_FILE_CORRUPT;
  
      if (decoder.begin_decoding() != jpgd::JPGD_SUCCESS)
          return ERR_FILE_CORRUPT;
  
      const int dst_bpl = image_width * comps;
  
      p_image.data.resize(dst_bpl * image_height);
  
      PoolVector<uint8_t>::Write dw = p_image.data.write();
  
      jpgd::uint8 *pImage_data = (jpgd::uint8 *)dw.ptr();
  
      for (int y = 0; y < image_height; y++) {
          const jpgd::uint8 *pScan_line;
          jpgd::uint scan_line_len;
          if (decoder.decode((const void **)&pScan_line, &scan_line_len) != jpgd::JPGD_SUCCESS) {
              return ERR_FILE_CORRUPT;
          }
  
          jpgd::uint8 *pDst = pImage_data + y * dst_bpl;
  
          if (comps == 1) {
              memcpy(pDst, pScan_line, dst_bpl);
          } else {
              // For images with more than 1 channel pScan_line will always point to a buffer
              // containing 32-bit RGBA pixels. Alpha is always 255 and we ignore it.
              for (int x = 0; x < image_width; x++) {
                  pDst[0] = pScan_line[x * 4 + 0];
                  pDst[1] = pScan_line[x * 4 + 1];
                  pDst[2] = pScan_line[x * 4 + 2];
                  pDst += 3;
              }
          }
      }
  
      //all good
  
      ImageData::Format fmt;
      if (comps == 1)
          fmt = ImageData::FORMAT_L8;
      else
          fmt = ImageData::FORMAT_RGB8;
  
      dw.release();
      p_image.width= image_width;
      p_image.height = image_height;
      p_image.mipmaps = false;
      p_image.format = fmt;
  
      return OK;
  }
  
  Error ImageLoaderJPG::load_image(ImageData &p_image, FileAccess *f, LoadParams params) {
  
      PoolVector<uint8_t> src_image;
      int src_image_len = f->get_len();
      ERR_FAIL_COND_V(src_image_len == 0, ERR_FILE_CORRUPT);
      src_image.resize(src_image_len);
  
      PoolVector<uint8_t>::Write w = src_image.write();
  
      f->get_buffer(&w[0], src_image_len);
  
      f->close();
  
      Error err = jpeg_load_image_from_buffer(p_image, w.ptr(), src_image_len);
  
      return err;
  }
  
  void ImageLoaderJPG::get_recognized_extensions(Vector<String> &p_extensions) const {
  
      p_extensions.push_back("jpg");
      p_extensions.push_back("jpeg");
  }
  
  ImageLoaderJPG::ImageLoaderJPG() {
  }
  