Iphone中HEIC文件格式转换及相关工具

C接口
void heif2jpg(const char heif_bin[], int input_buffer_size, const int jpg_quality, char output_buffer[], int output_buffer_size, const char* input_temp_filename)

作用: 将 Apple HEIF 转换为 JPEG
调用约定: Cdecl
参数 heif_bin: HEIF 文件二进制数据
参数 input_buffer_size: HEIF 文件二进制数据大小
参数 jpg_quality: 设定输出的 JPEG 图像的质量。取值 1-100，数值越高质量越好
参数 output_buffer: JPEG 图像输出缓冲区
参数 output_buffer_size: 输出缓冲区大小
参数 input_temp_filename: 函数运行时将会产生临时文件，通过此参数指定临时文件名。在执行结束后，临时文件可以被删除。
异常: 无

        [DllImport("HUD.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.Cdecl)]
        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);

        [DllImport("HUD.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.Cdecl)]
        private unsafe extern static void getexif(byte* heif_bin, int input_buffer_size, byte* ouput_buffer, int output_buffer_size, int* copysize);

        public static unsafe byte[] invoke_heif2jpg(byte[] heif_bin, int jpg_quality, string temp_filename, ref int copysize, bool include_exif, bool color_profile)
        {
            if (color_profile == true && DisplayP3Profile.Length == 1)
                throw new Exception();//没有ICC却指定要写入ICC

            var output_buffer = new byte[heif_bin.Length * 10];
            byte[] temp_filename_byte_array = System.Text.Encoding.Default.GetBytes(temp_filename);
            int[] copysize_array = new int[1] { 0 };
            fixed (byte* input = &heif_bin[0], output = &output_buffer[0], temp_filename_byte = &temp_filename_byte_array[0], icc_ptr = &DisplayP3Profile[0])
            fixed (int* copysize_p = &copysize_array[0])
            {
                heif2jpg(input, heif_bin.Length, jpg_quality, output, output_buffer.Length, temp_filename_byte, copysize_p, include_exif, color_profile, icc_ptr, DisplayP3Profile.Length);
            }
            copysize = copysize_array[0];
            return output_buffer;
        }

        public static unsafe string invoke_getexif(byte[] heif_bin, ref int copysize)
        {
            var output_buffer = new byte[65535];
            int[] copysize_array = new int[1] { 0 };
            fixed (byte* input = &heif_bin[0], output = &output_buffer[0])
            fixed (int* copysize_p = &copysize_array[0])
            {
                getexif(input, heif_bin.Length, output, output_buffer.Length, copysize_p);
            }
            copysize = copysize_array[0];
            return Encoding.Default.GetString(output_buffer, 0, copysize);
        }