这是接收迈瑞BC6800 HL7中内容的一部分，图片部分怎么解析不出来？

Question

// str3是下文中base64压缩后的内容
 byte[] bs2 = Convert.FromBase64String(str3);
 MemoryStream ms3 = new MemoryStream(bs2);
 Image image1 = Image.FromStream(ms3);
 image1.Save("D:\\1.jpg");

OBX|48|ED|15056^RBC Histogram. 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