几种截屏方法

待我称王封你为后i 2023-10-18 19:27 52阅读 0赞

1.
    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;  
    }