golang-Achieving picture Scaling

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Package Mainimport ("FMT" "Graphics" "Image" "Image/png" "Log" "Net/http" "OS" "StrConv" "Stri NGS ") Func Main () {http. Handlefunc ("/", Doimagehandler) http. Listenandserve ("127.0.0.1:6789", nil)}func Doimagehandler (w http. Responsewriter, R *http. Request) {fmt. Printf ("%q\n", strings. Split (R.url. Path, "/")) URL: = Strings. Split (R.url. Path, "/") If Len (URL)! = 3 {return} NEWDX, Uerr: = StrConv. Atoi (url[1]) if uerr! = Nil {log. Fatal (Uerr)} src, err: = LoadImage (url[2]) bound: = src. Bounds () dx: = bound. Dx () Dy: = bound. Dy () if err! = Nil {log. Fatal (ERR)}//thumbnail size DST: = image. Newrgba (image. Rect (0, 0, NEWDX, NEWDX*DY/DX))//Generate thumbnails, equal scale err = graphics. Scale (DST, SRC) if err! = Nil {log. Fatal (Err)} Header: = W.header () header. ADD ("Content-type", "Image/jpeg") png. Encode (W, DST)}//Load image decodes an image from a file of Image.func LoadImage (Path String) (img Image. Image, Err error) {file, err: = OS. Open (PATH) if err! = nil {return} defer file. Close () img, _, err = image. Decode (file) return}

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Package Masimport ("Code.google.com/p/graphics-go/graphics" "FMT" Z "github.com/nutzam/zgo" "image") func (MA *master) Activeimage (pobj string) error {//file absolute path var path string = pobj//Preserve source image structure var img image. Image//Picture type TYPEF: = Z.filetype (path)//load picture in picture format switch TYPEF {//JPEG case "JPEG"://Imagejpe    G img = z.imagejpeg (path)//JPG case "JPG"://imagejpeg img = z.imagejpeg (path)//PNG case "PNG": Imagepng img = z.imagepng (PATH)}//Determine if the original picture was successfully loaded if img = = Nil {//return error return to FMT. Errorf ("Active image decode exception ...")}//--------------------------------------------------------////Received Number of screens monisize: = ma. Nodeconf.monitorsize (MA)//Get screen resolution width: = ma. NodeConf.Resolution.Width Height: = ma. NodeConf.Resolution.Height//Get footage average widthmoni: = img. Bounds (). Dx ()/monisize.col Heightmoni: = img. Bounds (). Dy ()/monisize.row//--------------------------------------------------------////traverse screen, cut picture for _, Monis: = Range Ma. Nodeconf.layout {//Traversal node screen for _, Moni: = Range Monis {//get picture row: = Moni. Display.row col: = Moni. Display.col//Generate target background backgroundsrc: = Z.imagergba (Widthmoni, Heightmoni)//Generate target diagram Z.imagedra  Wrgba (Backgroundsrc, IMG, (COL-1) *widthmoni, (row-1) *heightmoni)//Generate final background map background: = Z.imagergba (width, Height)//produce the final graphics. Scale (background, BACKGROUNDSRC)//Save picture in picture format switch TYPEF {//JPEG case "JPEG"://I Mageencodejpeg Z.imageencodejpeg (FMT. Sprintf ("%s.pic_result/%d_%d.%s", Path, col, Row, TYPEF), background)//JPG case "JPG"://Imageenco Dejpeg Z.imageencodejpeg (FMT. Sprintf ("%s.pic_result/%d_%d.%s", Path, col, Row, TYPEF), background)//PNG case "PNG"://Imageenco Depng z.imageencodepng (FMT. Sprintf ("%s.pic_result/%d_%d.%s ", Path, col, Row, TYPEF), background)}}//Return nil} 

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Package Zimport ("image" "Image/draw" "Image/jpeg" "Image/png" "OS")//Read JPEG picture return Image.image object func IMAGEJP EG (ph string) image. Image {//Open picture file F, fileerr: = OS. Open (ph) if fileerr! = nil {return nil}//exit when closing file defer f.close ()//Decode J, Jerr: = jpeg. Decode (f) If Jerr = nil {return nil}//return decoded picture return j}//read PNG picture returns Image.image object func imagepng (ph stri NG) image. Image {//Open picture file F, fileerr: = OS. Open (ph) if fileerr! = nil {return nil}//exit when closing file defer f.close ()//decode P, Perr: = png.  Decode (f) if perr! = nil {return nil}//returns the decoded picture return p}//creates a blank picture object in accordance with the resolution Func Imagergba (width, height int) *image. RGBA {//build image, images. Rect (min x, min y, max x, min y) return image. Newrgba (image. Rect (0, 0, width, height))}//draws the picture to the picture func Imagedrawrgba (img *image. RGBA, Imgcode image. Image, x, y int) {//Draw images//image. The x, y coordinates of point a points, and the axes to the right and down add {0,0}//image. ZP ZP is the zero point//image. PtPt is shorthand for point{x, Y} draw. Draw (IMG, IMG. Bounds (), Imgcode, image. Pt (x, y), draw. OVER)}//JPEG will encode the image//Select the encoding parameter, the quality range from 1 to 100, the higher is better &jpeg. Options{90}func imageencodejpeg (ph string, img image.    Image) Error {//Make sure file parent directory exists fcheckparents (ph)//Open file waiting to write F: = filew (ph)//ensure file normal shutdown defer f.close () Write the file return JPEG. Encode (F, IMG, &jpeg. OPTIONS{100})}//PNG will encode the generated picture func imageencodepng (ph string, img image.    Image) Error {//Make sure file parent directory exists fcheckparents (ph)//Open file waiting to write F: = filew (ph)//ensure file normal shutdown defer f.close () Write the file return PNG. Encode (F, IMG)}