1 #include <iostream>
 2 #include <cstring>
 3 #include <fstream>
 4 #include <sstream>
 5 #include <windows.h>
 6 
 7 using namespace std;
 8 typedef  void (__stdcall *heif2jpg)(const char heif_bin[], int input_buffer_size, const int jpg_quality,
 9                                     char output_buffer[], int output_buffer_size, const char* input_temp_filename,
10                                     int* copysize, bool include_exif, bool color_profile, const char icc_bin[], int icc_size);
11 //读取文件内容
12 ostringstream readBinFile(char* filename,int &size)
13 {
14     fstream fs;
15     fs.open(filename, ios::in|ios::binary);
16     ostringstream oss;
17     oss << fs.rdbuf();
18     size=oss.str().length();
19     fs.close();
20     return oss;
21 }
22 
23 int main(int argc, char *argv[])
24 {
25     cout <<"Heic Convert Tool V1.0 <By midea0978>"<<endl;
26     cout <<"====================================\n"<<endl;
27     int quality=80;
28     if(argc<2)
29     {
30         cout <<"heic.exe <heic文件名> [jpg质量1-100,默认80]\n\n"<<endl;
31         return -1;
32     }
33     if(argc>=3) quality=atoi(argv[2]);
34     HMODULE hModule;
35     hModule = LoadLibraryA("HUD.dll");
36     if ( NULL == hModule)
37     {
38         DWORD error_id=GetLastError();
39         cout<<"加载hud.dll失败:"<<error_id<<endl;
40         return -1;
41     }
42     heif2jpg func = NULL;
43     func = (heif2jpg)GetProcAddress(hModule, "heif2jpg");
44     char drive[_MAX_DRIVE];
45     char dir[_MAX_DIR];
46     char fname[_MAX_FNAME];
47     char ext[_MAX_EXT];
48     _splitpath(argv[1], drive, dir, fname, ext);
49     string ofilename;
50     ofilename+=drive;
51     ofilename+=dir;
52     ofilename+=fname;
53     ofilename+=".jpg";
54     printf("输出JPG文件 %s\n",ofilename.c_str());
55     int imgsize=0;
56     ostringstream heicdata=readBinFile(argv[1],imgsize);
57     int outsize=10*imgsize;
58     char* outbuffer;
59     int copysize[]= {0};
60     outbuffer = (char*)malloc(outsize);
61     memset(outbuffer, 0, outsize);
62     char temppath[MAX_PATH];
63     GetTempPath(MAX_PATH,temppath);
64     string tempfile;
65     tempfile+=temppath;
66     tempfile+="\\temp.dat";
67     func(heicdata.str().c_str(),imgsize,quality,outbuffer,outsize,tempfile.c_str(),copysize,true,false,NULL,0);
68     ofstream outfile(ofilename,ios::binary);
69     outfile.write(outbuffer,copysize[0]);
70     outfile.close();
71     remove(tempfile.c_str());
72     FreeLibrary(hModule);
73     return 0;
74 }

对应C#的调用方式，代码来自于下面的URL

 1 [DllImport("HUD.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.Cdecl)]
 2 private unsafe extern static void heif2jpg(byte* heif_bin, int input_buffer_size, int jpg_quality, byte* ouput_buffer, int output_buffer_size, byte* temp_filename, int* copysize, bool include_exif, bool color_profile, byte* icc_bin, int icc_size);
 3 
 4 [DllImport("HUD.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.Cdecl)]
 5 private unsafe extern static void getexif(byte* heif_bin, int input_buffer_size, byte* ouput_buffer, int output_buffer_size, int* copysize);
 6 
 7 public static unsafe byte[] invoke_heif2jpg(byte[] heif_bin, int jpg_quality, string temp_filename, ref int copysize, bool include_exif, bool color_profile)
 8 {
 9     if (color_profile == true && DisplayP3Profile.Length == 1)
10         throw new Exception();//没有ICC却指定要写入ICC
11 
12     var output_buffer = new byte[heif_bin.Length * 10];
13     byte[] temp_filename_byte_array = System.Text.Encoding.Default.GetBytes(temp_filename);
14     int[] copysize_array = new int[1] { 0 };
15     fixed (byte* input = &heif_bin[0], output = &output_buffer[0], temp_filename_byte = &temp_filename_byte_array[0], icc_ptr = &DisplayP3Profile[0])
16     fixed (int* copysize_p = &copysize_array[0])
17     {
18         heif2jpg(input, heif_bin.Length, jpg_quality, output, output_buffer.Length, temp_filename_byte, copysize_p, include_exif, color_profile, icc_ptr, DisplayP3Profile.Length);
19     }
20     copysize = copysize_array[0];
21     return output_buffer;
22 }
23 
24 public static unsafe string invoke_getexif(byte[] heif_bin, ref int copysize)
25 {
26     var output_buffer = new byte[65535];
27     int[] copysize_array = new int[1] { 0 };
28     fixed (byte* input = &heif_bin[0], output = &output_buffer[0])
29     fixed (int* copysize_p = &copysize_array[0])
30     {
31         getexif(input, heif_bin.Length, output, output_buffer.Length, copysize_p);
32     }
33     copysize = copysize_array[0];
34     return Encoding.Default.GetString(output_buffer, 0, copysize);
35 }

详细代码参考：https://github.com/liuziangexit/HEIF-Utility/blob/master/HEIF%20Utility/invoke_dll.cs　　

其他的开源库：

https://github.com/libvips/libvips

ibvips是一个图像处理库。与类似的库相比，libvips运行迅速且几乎不占用内存。libvips是根据LGPL 2.1+许可的。

它具有约300种运算， 涵盖算术，直方图，卷积，形态运算，频率滤波，颜色，重采样，统计等。它支持多种数字类型，从8位int到128位复数。图像可以具有任意数量的波段。它支持各种图像格式，包括JPEG，TIFF，PNG，WebP，HEIC，FITS，Matlab，OpenEXR，PDF，SVG，HDR，PPM / PGM / PFM，CSV，GIF，分析，NIfTI，DeepZoom和OpenSlide 。它还可以通过ImageMagick或GraphicsMagick加载图像，使其与DICOM等格式一起使用。