Exemplo n.º 1
0
        /// <summary>
        /// 以填充模式缩略图片
        /// </summary>
        public virtual void ThumbByFill(Stream sourceStream, Stream ouputStream, int width, int height, bool highQuality)
        {
            Image source = Image.FromStream(sourceStream);

            if (source.RawFormat.Guid != ImageFormat.Gif.Guid)
            {
                throw new IOException(string.Format("文件不是GIF格式的图片!"));
            }

            if (width == 0 || (width > 200 && width > source.Width))
            {
                width = source.Width;                                                     //做200的限制,实际文件超过200的,就以实际为大小
            }
            if (height == 0 || (height > 200 && height > source.Height))
            {
                height = source.Height;                                                         //做200的限制,实际文件超过200的,就以实际为大小
            }
            int x = 0, y = 0, tw, th;

            //先等比缩放
            if (source.Width > source.Height)
            {
                //宽大于高,以宽等比缩放
                tw = source.Width > width ? width : source.Width;
                th = (int)(source.Height * (double)tw / (double)source.Width);

                if (th > height)//得到的结果比需要的高度高,则根据高度缩放
                {
                    th = source.Height > height ? height : source.Height;
                    tw = (int)(source.Width * (double)th / (double)source.Height);
                }
            }
            else
            {
                //高大于宽,以高等比缩放
                th = source.Height > height ? height : source.Height;
                tw = (int)(source.Width * (double)th / (double)source.Height);

                if (tw > width)//得到的结果比需要的宽度宽,则根据宽度缩放
                {
                    tw = source.Width > width ? width : source.Width;
                    th = (int)(source.Height * (double)tw / (double)source.Width);
                }
            }

            if (tw < width)
            {
                x = (width - tw) / 2;
            }
            if (th < height)
            {
                y = (height - th) / 2;
            }

            sourceStream.Seek(0, SeekOrigin.Begin);

            Bitmap       ora_Img = new Bitmap(sourceStream);
            List <Frame> frames = new List <Frame>();

            foreach (Guid guid in ora_Img.FrameDimensionsList)
            {
                FrameDimension frameDimension = new FrameDimension(guid);
                int            frameCount     = ora_Img.GetFrameCount(frameDimension);
                byte[]         buffer         = ora_Img.GetPropertyItem(20736).Value;
                for (int i = 0; i < frameCount; i++)
                {
                    if (ora_Img.SelectActiveFrame(frameDimension, i) == 0)
                    {
                        int delay = BitConverter.ToInt32(buffer, i * 4);
                        System.IO.MemoryStream stream = new System.IO.MemoryStream();

                        source = Image.FromHbitmap(ora_Img.GetHbitmap()) as Bitmap;
                        Color  backColor = Color.White;
                        Bitmap img       = new Bitmap(width, height);
                        img.SetResolution(72f, 72f);
                        img.SetResolution(source.HorizontalResolution, source.VerticalResolution);
                        using (Graphics gdiobj = Graphics.FromImage(img))
                        {
                            SetQuality(gdiobj);
                            gdiobj.FillRectangle(new SolidBrush(Color.White), 0, 0, width, height);
                            Rectangle destrect = new Rectangle(x, y, tw, th);
                            gdiobj.DrawImage(source, destrect, 0, 0, source.Width,
                                             source.Height, GraphicsUnit.Pixel);
                        }
                        Frame frame = new Frame(img, delay, backColor);
                        frames.Add(frame);
                    }
                }
            }
            AnimatedGifEncoder gif = new AnimatedGifEncoder();

            gif.Start(ouputStream);
            gif.SetRepeat(0);
            for (int i = 0; i < frames.Count; i++)
            {
                gif.SetDelay(frames[i].Delay);
                gif.AddFrame(frames[i].Img);
            }
            gif.Finish();
        }
Exemplo n.º 2
0
        /// <summary>
        /// 保留全图的缩放(但会使图像变形)
        /// </summary>
        /// <param name="sourceStream"></param>
        /// <param name="ouputStream"></param>
        /// <param name="width"></param>
        /// <param name="height"></param>
        /// <param name="format"></param>
        /// <param name="highQuality"></param>
        public virtual void ThumbByFull(Stream sourceStream, Stream ouputStream, int width, int height, bool highQuality)
        {
            Image source = null;

            try
            {
                source = System.Drawing.Image.FromStream(sourceStream);

                ImageZip(source.Width, source.Height, ref width, ref height);

                sourceStream.Seek(0, SeekOrigin.Begin);

                Bitmap       ora_Img = new Bitmap(sourceStream);
                List <Frame> frames  = new List <Frame>();
                foreach (Guid guid in ora_Img.FrameDimensionsList)
                {
                    FrameDimension frameDimension = new FrameDimension(guid);
                    int            frameCount     = ora_Img.GetFrameCount(frameDimension);
                    byte[]         buffer         = ora_Img.GetPropertyItem(20736).Value;
                    for (int i = 0; i < frameCount; i++)
                    {
                        if (ora_Img.SelectActiveFrame(frameDimension, i) == 0)
                        {
                            int delay = BitConverter.ToInt32(buffer, i * 4);
                            System.IO.MemoryStream stream = new System.IO.MemoryStream();

                            source = Image.FromHbitmap(ora_Img.GetHbitmap()) as Bitmap;
                            Color  backColor = Color.White;
                            Bitmap img       = new Bitmap(width, height);

                            //img.SetResolution(72f, 72f);
                            img.SetResolution(source.HorizontalResolution, source.VerticalResolution);
                            using (Graphics gdiobj = Graphics.FromImage(img))
                            {
                                SetQuality(gdiobj);
                                gdiobj.FillRectangle(new SolidBrush(Color.White), 0, 0, width, height);
                                Rectangle destrect = new Rectangle(0, 0, width, height);
                                gdiobj.DrawImage(source, destrect, 0, 0, source.Width,
                                                 source.Height, GraphicsUnit.Pixel);
                            }

                            Frame frame = new Frame(img, delay, backColor);
                            frames.Add(frame);
                        }
                    }
                }
                AnimatedGifEncoder gif = new AnimatedGifEncoder();
                gif.Start(ouputStream);
                gif.SetRepeat(0);
                for (int i = 0; i < frames.Count; i++)
                {
                    gif.SetDelay(frames[i].Delay);
                    gif.AddFrame(frames[i].Img);
                }
                gif.Finish();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                source.Dispose();
            }
        }
Exemplo n.º 3
0
        public virtual void ThumbByCut(Stream sourceStream, Stream ouputStream, int width, int height, bool highQuality)
        {
            Image source = null;

            try
            {
                source = System.Drawing.Image.FromStream(sourceStream);

                //先等比裁剪
                int tw = width;
                int th = height;
                if (tw == 0 && th != 0)
                {
                    tw = (int)(source.Width * (double)th / source.Height);
                }
                else if (th == 0 && tw != 0)
                {
                    th = (int)(source.Height * (double)width / source.Width);
                }
                else if (th == 0 && tw == 0)
                {
                    th = source.Height;
                    tw = source.Width;
                }

                int cutWidth  = 0;
                int cutHeight = 0;

                int bywWidth  = source.Width;
                int bywHeight = (int)(source.Width * (double)th / tw);
                if (bywHeight < 1)
                {
                    bywHeight = 1;
                }

                int byhWidth = (int)(source.Height * (double)tw / th);
                if (byhWidth < 1)
                {
                    byhWidth = 1;
                }
                int byhHeight = source.Height;


                if (bywHeight > source.Height)//如果根据宽度裁剪得到的高度超过原始高度
                {
                    cutWidth  = byhWidth;
                    cutHeight = byhHeight;
                }
                else if (byhWidth > source.Width) //如果根据高度裁剪得到的宽度高过原始宽度
                {
                    cutWidth  = bywWidth;
                    cutHeight = bywHeight;
                }
                else
                {
                    //如果两个依据都符合,则根据面积的大小判断,面积越大,精确度越高
                    if ((bywWidth * bywHeight) > (byhWidth * byhHeight))
                    {
                        cutWidth  = bywWidth;
                        cutHeight = bywHeight;
                    }
                    else
                    {
                        cutWidth  = byhWidth;
                        cutHeight = byhHeight;
                    }
                }

                //根据中心点,得到裁剪的起始地址
                int x = (int)((double)source.Width / 2 - (double)cutWidth / 2);
                int y = (int)((double)source.Height / 2 - (double)cutHeight / 2);
                if (x < 0)
                {
                    x = 0;
                }
                if (y < 0)
                {
                    y = 0;
                }


                sourceStream.Seek(0, SeekOrigin.Begin);

                Bitmap       ora_Img = new Bitmap(sourceStream);
                List <Frame> frames  = new List <Frame>();
                foreach (Guid guid in ora_Img.FrameDimensionsList)
                {
                    FrameDimension frameDimension = new FrameDimension(guid);
                    int            frameCount     = ora_Img.GetFrameCount(frameDimension);
                    byte[]         buffer         = ora_Img.GetPropertyItem(20736).Value;
                    for (int i = 0; i < frameCount; i++)
                    {
                        if (ora_Img.SelectActiveFrame(frameDimension, i) == 0)
                        {
                            int delay = BitConverter.ToInt32(buffer, i * 4);
                            System.IO.MemoryStream stream = new System.IO.MemoryStream();

                            source = Image.FromHbitmap(ora_Img.GetHbitmap()) as Bitmap;
                            Color  backColor = Color.White;
                            Bitmap img       = new Bitmap(cutWidth, cutHeight, PixelFormat.Format32bppArgb);

                            using (Graphics g = Graphics.FromImage(img))
                            {
                                Rectangle destRect = new Rectangle(0, 0, cutWidth, cutHeight);
                                g.DrawImage(source, destRect, x, y, cutWidth, cutHeight, GraphicsUnit.Pixel);
                                using (MemoryStream ms = new MemoryStream())
                                {
                                    img.Save(ms, ImageFormat.Jpeg);
                                    source.Dispose();
                                    source = Image.FromStream(ms);

                                    //再缩放
                                    ImageZip(cutWidth, cutHeight, ref width, ref height);

                                    img = new Bitmap(width, height);
                                    //img.SetResolution(72f, 72f);
                                    img.SetResolution(source.HorizontalResolution, source.VerticalResolution);
                                    using (Graphics gdiobj = Graphics.FromImage(img))
                                    {
                                        SetQuality(gdiobj);
                                        gdiobj.FillRectangle(new SolidBrush(Color.White), 0, 0, width, height);
                                        Rectangle destrect = new Rectangle(0, 0, width, height);
                                        gdiobj.DrawImage(source, destrect, 0, 0, source.Width,
                                                         source.Height, GraphicsUnit.Pixel);
                                    }
                                }
                            }
                            Frame frame = new Frame(img, delay, backColor);
                            frames.Add(frame);
                        }
                    }
                }
                AnimatedGifEncoder gif = new AnimatedGifEncoder();
                gif.Start(ouputStream);
                gif.SetRepeat(0);
                for (int i = 0; i < frames.Count; i++)
                {
                    gif.SetDelay(frames[i].Delay);
                    gif.AddFrame(frames[i].Img);
                }
                gif.Finish();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                source.Dispose();
            }
        }