压缩图片

/// <summary>
        /// 压缩图片
        /// </summary>
        /// <param name="fileByte">图片字节数组</param>
        /// <param name="quality">压缩质量0-100之间，数值越大质量越高</param>
        /// <returns></returns>
        public static byte[] CompressionImage(byte[] fileByte, long quality)
        {
            using (MemoryStream fileStream = new MemoryStream(fileByte))
            {
                using (System.Drawing.Image img = System.Drawing.Image.FromStream(fileStream))
                {
                    using (Bitmap bitmap = new Bitmap(img))
                    {
                        ImageCodecInfo CodecInfo = GetEncoder(img.RawFormat);
                        System.Drawing.Imaging.Encoder myEncoder = System.Drawing.Imaging.Encoder.Quality;
                        EncoderParameters myEncoderParameters = new EncoderParameters(1);
                        EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, quality);
                        myEncoderParameters.Param[0] = myEncoderParameter;
                        using (MemoryStream ms = new MemoryStream())
                        {
                            bitmap.Save(ms, CodecInfo, myEncoderParameters);
                            myEncoderParameters.Dispose();
                            myEncoderParameter.Dispose();
                            return ms.ToArray();
                        }
                    }
                }
            }
        }
        /// <summary>
        /// 获取指定图片编码信息
        /// </summary>
        /// <param name="format"></param>
        /// <returns></returns>
        private static ImageCodecInfo GetEncoder(ImageFormat format)
        {
            ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
            foreach (ImageCodecInfo codec in codecs)
            {
                if (codec.FormatID == format.Guid)
                {
                    return codec;
                }
            }
            return null;
        }