几种截屏方法

  

   

    

     

    
    

     

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      UIGraphicsBeginImageContextWithOptions(pageView.page.bounds.size, YES, zoomScale);
     
    
   

    

     

    
    

     

              [pageView.page.layer renderInContext:UIGraphicsGetCurrentContext()];
     
    
   

    

     

    
    

     

              UIImage *uiImage = UIGraphicsGetImageFromCurrentImageContext();
     
    
   

    

     

    
    

     
        UIGraphicsEndImageContext();
     
    
   

    

     

    
    

     

      2.
     
    
   

    

     

    
    

     

      - (UIImage *) glToUIImage {
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     

          DWScrollView *pageView = [self getActivePageView];
     
    
   

    

     

    
    

     

             pageView.page.backgroundColor = [UIColor clearColor];
     
    
   

    

     

    
    

     
  // self.backgroundColor=[UIColor clearColor];
     
    
   

    

     

    
    

     

          NSInteger myDataLength = 320 * 308 * 4;
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    // allocate array and read pixels into it.
     
    
   

    

     

    
    

     

          GLubyte *buffer = (GLubyte *) malloc(myDataLength);
     
    
   

    

     

    
    

     
    glReadPixels(0, 0, 320, 308, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    // gl renders "upside down" so swap top to bottom into new array.
     
    
   

    

     

    
    

     
    // there's gotta be a better way, but this works.
     
    
   

    

     

    
    

     

          GLubyte *buffer2 = (GLubyte *) malloc(myDataLength);
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    for(int y = 0; y <308; y++)
     
    
   

    

     

    
    

     

          {
     
    
   

    

     

    
    

     
        for(int x = 0; x <320 * 4; x++)
     
    
   

    

     

    
    

     

              {
     
    
   

    

     

    
    

     
            if(buffer[y* 4 * 320 + x]==0)
     
    
   

    

     

    
    

     

                      buffer2[(307 - y) * 320 * 4 + x]=1;
     
    
   

    

     

    
    

     
            else
     
    
   

    

     

    
    

     

                      buffer2[(307 - y) * 320 * 4 + x] = buffer[y* 4 * 320 + x];
     
    
   

    

     

    
    

     

              }
     
    
   

    

     

    
    

     

          }
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    // make data provider with data.
     
    
   

    

     

    
    

     

          CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, buffer2, myDataLength, NULL);
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    // prep the ingredients
     
    
   

    

     

    
    

     
    int bitsPerComponent = 8;
     
    
   

    

     

    
    

     
    int bitsPerPixel = 32;
     
    
   

    

     

    
    

     
    int bytesPerRow = 4 * 320;
     
    
   

    

     

    
    

     

          CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();
     
    
   

    

     

    
    

     

          CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault;
     
    
   

    

     

    
    

     

          CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    // make the cgimage
     
    
   

    

     

    
    

     

          CGImageRef imageRef = CGImageCreate(320, 308, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    // then make the uiimage from that
     
    
   

    

     

    
    

     

          UIImage *myImage = [UIImage imageWithCGImage:imageRef];
     
    
   

    

     

    
    

     
    UIImageWriteToSavedPhotosAlbum(myImage, nil, nil, nil);
     
    
   

    

     

    
    

     
    return myImage;
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      3.
     
    
   

    

     

    
    

     

      // get screen
     
    
   

    

     

    
    

     

      - (void)grabScreen {
     
    
   

    

     

    
    

     
    unsigned char buffer[320*480*4];
     
    
   

    

     

    
    

     
    glReadPixels(0,0,320,480,GL_RGBA,GL_UNSIGNED_BYTE,&buffer);
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     

          CGDataProviderRef ref = CGDataProviderCreateWithData(NULL, &buffer, 320*480*4, NULL);
     
    
   

    

     

    
    

     

          CGImageRef iref = CGImageCreate(320,480,8,32,320*4,CGColorSpaceCreateDeviceRGB(),kCGBitmapByteOrderDefault,ref,NULL,true,kCGRenderingIntentDefault);
     
    
   

    

     

    
    

     

          CGFloat width = CGImageGetWidth(iref);
     
    
   

    

     

    
    

     

          CGFloat height = CGImageGetHeight(iref);
     
    
   

    

     

    
    

     
    size_t length = width*height*4;
     
    
   

    

     

    
    

     
    uint32_t *pixels = (uint32_t *)malloc(length);
     
    
   

    

     

    
    

     

          CGContextRef context = CGBitmapContextCreate(pixels, width, height, 8, 320*4, CGImageGetColorSpace(iref), kCGImageAlphaLast | kCGBitmapByteOrder32Big);
     
    
   

    

     

    
    

     
    CGContextTranslateCTM(context, 0.0, height);
     
    
   

    

     

    
    

     
    CGContextScaleCTM(context, 1.0, -1.0);
     
    
   

    

     

    
    

     
    CGContextDrawImage(context, CGRectMake(0.0, 0.0, width, height), iref);
     
    
   

    

     

    
    

     

          CGImageRef outputRef = CGBitmapContextCreateImage(context);
     
    
   

    

     

    
    

     

          UIImage *outputImage = [UIImage imageWithCGImage:outputRef];
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    UIImageWriteToSavedPhotosAlbum(outputImage, nil, nil, nil); 
     
    
   

    

     

    
    

     
    
     
    
   

    

     

    
    

     
    CGContextRelease(context);
     
    
   

    

     

    
    

     
    CGImageRelease(iref);
     
    
   

    

     

    
    

     
    CGDataProviderRelease(ref);
     
    
   

    

     

    
    

     

      } 
     
    
   

    

     

    
    

     

      4.
     
    
   

    

     

    
    

     

      CGImageRef UIGetScreenImage();
     
    
   

    

     

    
    

     

      void SaveScreenImage(NSString *path)
     
    
   

    

     

    
    

     

      {
     
    
   

    

     

    
    

     

          NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
     
    
   

    

     

    
    

     

          CGImageRef cgImage = UIGetScreenImage();
     
    
   

    

     

    
    

     
        void *imageBytes = NULL;
     
    
   

    

     

    
    

     
        if (cgImage == NULL) {
     
    
   

    

     

    
    

     

                      CGColorSpaceRef colorspace = CGColorSpaceCreateDeviceRGB();
     
    
   

    

     

    
    

     

                      imageBytes = malloc(320 * 480 * 4);
     
    
   

    

     

    
    

     

                      CGContextRef context = CGBitmapContextCreate(imageBytes, 320, 480, 8, 320 * 4, colorspace, kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big);
     
    
   

    

     

    
    

     
                CGColorSpaceRelease(colorspace);
     
    
   

    

     

    
    

     
                for (UIWindow *window in [[UIApplication sharedApplication] windows]) {
     
    
   

    

     

    
    

     

                              CGRect bounds = [window bounds];
     
    
   

    

     

    
    

     

                              CALayer *layer = [window layer];
     
    
   

    

     

    
    

     
                        CGContextSaveGState(context);
     
    
   

    

     

    
    

     
                        if ([layer contentsAreFlipped]) {
     
    
   

    

     

    
    

     
                                CGContextTranslateCTM(context, 0.0f, bounds.size.height);
     
    
   

    

     

    
    

     
                                CGContextScaleCTM(context, 1.0f, -1.0f);
     
    
   

    

     

    
    

     

                              }
     
    
   

    

     

    
    

     

                              [layer renderInContext:(CGContextRef)context];
     
    
   

    

     

    
    

     
                        CGContextRestoreGState(context);
     
    
   

    

     

    
    

     

                      }
     
    
   

    

     

    
    

     

                      cgImage = CGBitmapContextCreateImage(context);
     
    
   

    

     

    
    

     
                CGContextRelease(context);
     
    
   

    

     

    
    

     

              }
     
    
   

    

     

    
    

     

          NSData *pngData = UIImagePNGRepresentation([UIImage imageWithCGImage:cgImage]);
     
    
   

    

     

    
    

     
    CGImageRelease(cgImage);
     
    
   

    

     

    
    

     
        if (imageBytes)
     
    
   

    

     

    
    

     
                free(imageBytes);
     
    
   

    

     

    
    

     

          [pngData writeToFile:path atomically:YES];
     
    
   

    

     

    
    

     

          [pool release];
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      5.
     
    
   

    

     

    
    

     

        + (UIImage *)imageWithScreenContents
     
    
   

    

     

    
    

     

      {
     
    
   

    

     

    
    

     

           CGImageRef cgScreen = UIGetScreenImage();
     
    
   

    

     

    
    

     
     if (cgScreen) {
     
    
   

    

     

    
    

     

               UIImage *result = [UIImage imageWithCGImage:cgScreen];
     
    
   

    

     

    
    

     
         CGImageRelease(cgScreen);
     
    
   

    

     

    
    

     
         return result;
     
    
   

    

     

    
    

     

           }
     
    
   

    

     

    
    

     
     return nil;
     
    
   

    

     

    
    

     

      } 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      在程序中如何把两张图片合成为一张图片   
     
    
   

    

     

    
    

     

      - (UIImage *)addImage:(UIImage *)image1 toImage:(UIImage *)image2 {  
     
    
   

    

     

    
    

     
    UIGraphicsBeginImageContext(image1.size);  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
    // Draw image1 
     
    
   

    

     

    
    

     

          [image1 drawInRect:CGRectMake(0, 0, image1.size.width, image1.size.height)];  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
    // Draw image2 
     
    
   

    

     

    
    

     

          [image2 drawInRect:CGRectMake(0, 0, image2.size.width, image2.size.height)];  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

          UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext();  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
    UIGraphicsEndImageContext();  
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
    return resultingImage;  
     
    
   

    

     

    
    

     

      } 
     
    
  
 

  
 
 

文章来源: zzzili.blog.csdn.net，作者：清雨小竹，版权归原作者所有，如需转载，请联系作者。

原文链接：zzzili.blog.csdn.net/article/details/9097135