Iphone上开发ARToolkit应用的注意事项总结.doc

Iphone上开发ARToolkit应用的注意事项总结文章分类:移动开发 原创文章，欢迎转载，转载时务必注明原文地址及作者 1. 如何调整uiimage的大小 C代码 1. /改变图片到指定的尺寸 2. -(UIImage*)resizedImage:(UIImage*)inImageinRect:(CGRect)thumbRect 3. 4. /Createsabitmap-basedgraphicscontextandmakesitthecurrentcontext. 5. UIGraphicsBeginImageContext(thumbRect.size); 6. inImagedrawInRect:thumbRect; 7. returnUIGraphicsGetImageFromCurrentImageContext(); 8. /改变图片到指定的尺寸-(UIImage*)resizedImage:(UIImage*)inImage inRect:(CGRect)thumbRect / Creates a bitmap-based graphics context and makes it the current context.UIGraphicsBeginImageContext(thumbRect.size);inImage drawInRect:thumbRect;return UIGraphicsGetImageFromCurrentImageContext();2. 如何取得uiimage图像中的RGB数据 C代码 1. /uiimage编码成ARGB 2. -(CGContextRef)createARGBBitmapContextFromImage:(CGImageRef)inImage 3. 4. CGContextRefcontext=NULL; 5. CGColorSpaceRefcolorSpace; 6. void*bitmapData; 7. intbitmapByteCount; 8. intbitmapBytesPerRow; 9. 10. /Getimagewidth,height.Wellusetheentireimage. 11. size_tpixelsWide=CGImageGetWidth(inImage); 12. size_tpixelsHigh=CGImageGetHeight(inImage); 13. /intpixelsWide,pixelsHigh; 14. /ar2VideoGetSize(gVid,&pixelsWide,&pixelsHigh); 15. 16. /Declarethenumberofbytesperrow.Eachpixelinthebitmapinthis 17. /exampleisrepresentedby4bytes;8bitseachofred,green,blue,and 18. /alpha. 19. bitmapBytesPerRow=(pixelsWide*4); 20. bitmapByteCount=(bitmapBytesPerRow*pixelsHigh); 21. 22. /UsethegenericRGBcolorspace. 23. colorSpace=CGColorSpaceCreateDeviceRGB(); 24. /colorSpace=CGImageGetColorSpace(inImage); 25. 26. if(colorSpace=NULL) 27. 28. fprintf(stderr,Errorallocatingcolorspacen); 29. returnNULL; 30. 31. 32. /Allocatememoryforimagedata.Thisisthedestinationinmemory 33. /whereanydrawingtothebitmapcontextwillberendered. 34. bitmapData=malloc(bitmapByteCount); 35. if(bitmapData=NULL) 36. 37. fprintf(stderr,Memorynotallocated!); 38. CGColorSpaceRelease(colorSpace); 39. returnNULL; 40. 41. 42. /Createthebitmapcontext.Wewantpre-multipliedARGB,8-bits 43. /percomponent.Regardlessofwhatthesourceimageformatis 44. /(CMYK,Grayscale,andsoon)itwillbeconvertedovertotheformat 45. /specifiedherebyCGBitmapContextCreate. 46. context=CGBitmapContextCreate(bitmapData, 47. pixelsWide, 48. pixelsHigh, 49. 8,/bitspercomponent 50. bitmapBytesPerRow, 51. colorSpace, 52. kCGImageAlphaPremultipliedFirst);/kCGImageAlphaNone 53. if(context=NULL) 54. 55. free(bitmapData); 56. fprintf(stderr,Contextnotcreated!); 57. 58. 59. /Makesureandreleasecolorspacebeforereturning 60. CGColorSpaceRelease(colorSpace); 61. 62. returncontext; 63. /uiimage编码成ARGB- (CGContextRef) createARGBBitmapContextFromImage:(CGImageRef) inImage CGContextRef context = NULL; CGColorSpaceRef colorSpace; void * bitmapData; int bitmapByteCount; int bitmapBytesPerRow; / Get image width, height. Well use the entire image. size_t pixelsWide = CGImageGetWidth(inImage); size_t pixelsHigh = CGImageGetHeight(inImage);/int pixelsWide, pixelsHigh;/ar2VideoGetSize(gVid, &pixelsWide, &pixelsHigh); / Declare the number of bytes per row. Each pixel in the bitmap in this / example is represented by 4 bytes; 8 bits each of red, green, blue, and / alpha. bitmapBytesPerRow = (pixelsWide * 4); bitmapByteCount = (bitmapBytesPerRow * pixelsHigh); / Use the generic RGB color space. colorSpace = CGColorSpaceCreateDeviceRGB();/colorSpace = CGImageGetColorSpace(inImage); if (colorSpace = NULL) fprintf(stderr, Error allocating color spacen); return NULL; / Allocate memory for image data. This is the destination in memory / where any drawing to the bitmap context will be rendered. bitmapData = malloc( bitmapByteCount ); if (bitmapData = NULL) fprintf (stderr, Memory not allocated!); CGColorSpaceRelease( colorSpace ); return NULL; / Create the bitmap context. We want pre-multiplied ARGB, 8-bits / per component. Regardless of what the source image format is / (CMYK, Grayscale, and so on) it will be converted over to the format / specified here by CGBitmapContextCreate. context = CGBitmapContextCreate (bitmapData, pixelsWide, pixelsHigh, 8, / bits per component bitmapBytesPerRow, colorSpace, kCGImageAlphaPremultipliedFirst);/ kCGImageAlphaNone if (context = NULL) free (bitmapData); fprintf (stderr, Context not created!); / Make sure and release colorspace before returning CGColorSpaceRelease( colorSpace ); return context;3. 如何识别多个marker文件 C代码 1. /配置ar识别marker参数 2. staticintsetupMarker(constchar*patt_name,int*patt_id,ARHandle*arhandle,ARPattHandle*pattHandle_p) 3. 4. /此处修改支持识别多个marker文件 5. if(*pattHandle_p=NULL) 6. *pattHandle_p=arPattCreateHandle(); 7. if(*pattHandle_p=NULL) 8. fprintf(stderr,setupMarker():Error:arPattCreateHandle.n); 9. return(FALSE); 10. 11. arPattAttach(arhandle,*pattHandle_p); 12. 13. 14. if(*patt_id=arPattLoad(*pattHandle_p,patt_name)0) 15. fprintf(stderr,setupMarker():Errorloadingpatternfile%s.n,patt_name); 16. arPattDeleteHandle(*pattHandle_p); 17. return(FALSE); 18. 19. 20. return(TRUE); 21. /配置ar识别marker参数static int setupMarker(const char *patt_name, int *patt_id, ARHandle *arhandle, ARPattHandle *pattHandle_p)/此处修改支持识别多个marker文件if (*pattHandle_p = NULL) *pattHandle_p = arPattCreateHandle();if (*pattHandle_p = NULL) fprintf(stderr, setupMarker(): Error: arPattCreateHandle.n);return (FALSE);arPattAttach(arhandle, *pattHandle_p); if (*patt_id = arPattLoad(*pattHandle_p, patt_name) markerInfo0.vertexgARHandle-markerInfo0. vertex5. 如何绘画识别出的marker的外框以及对于的图片背景 C代码 1. /画出marker的外框 2. -(void)drawMarkerRect 3. CGContextRefcontext=UIGraphicsGetCurrentContext(); 4. CGContextSetStrokeColorWithColor(context,UIColorgreenColor.CGColor);/颜色 5. CGContextSetLineWidth(context,2.0);/线宽 6. /画线 7. CGContextMoveToPoint(context,x1,y1); 8. CGContextAddLineToPoint(context,x2,y2); 9. CGContextAddLineToPoint(context,x3,y3); 10. CGContextAddLineToPoint(context,x4,y4); 11. CGContextAddLineToPoint(context,x1,y1); 12. CGContextStrokePath(context); 13. 14. /描绘识别marker外框的模式 15. self.backgroundColor=UIColorcolorWithPatternImage:mimage;/画出marker的外框- (void)drawMarkerRect CGContextRef context = UIGraphicsGetCurrentContext();CGContextSetStrokeColorWithColor(context, UIColor greenColor.CGColor);/颜色CGContextSetLineWidth(context, 2.0);/线宽/画线CGContextMoveToPoint(context,x1, y1);CGContextAddLineToPoint(context, x2, y2);CGContextAddLineToPoint(context, x3, y3);CGContextAddLineToPoint(context, x4, y4);CGContextAddLineToPoint(context, x1, y1);CGContextStrokePath(context);/描绘识别marker外框的模式self.backgroundColor = UIColor colorWithPatternImage:mimage;6. 如何利用NSTimer来实现异步调用 C代码 1. /延迟加载视频，让画出marker的画面显示一下 2. mTimer=NSTimerscheduledTimerWithTimeInterval:INTERVAL_SECtarget:selfselector:selector(playMovie:)userInfo:nilrepeats:NO; 3. /播放视频 4. -(void)playMovie:(NSTimer*)timer 5. viewControllerplayMovie:currentTag.movie; 6. mTimerrelease; 7. mTimer=nil; 8. /延迟加载视频，让画出marker的画面显示一下mTimer = NSTimer scheduledTimerWithTimeInterval:INTERVAL_SEC target:self selector:selector(playMovie:) userInfo:nil repeats:NO;/播放视频- (void)playMovie:(NSTimer *)timer viewController playMovie:currentTag.movie;mTimer release;mTimer = nil;7. 如何保存当前图片到图片文件夹 C代码 1. /保持图片到照片文件夹 2. -(void)saveToPhotosAlbum:(UIImage*)image 3. CGContextRefcontext=UIGraphicsGetCurrentContext(); 4. UIImageWriteToSavedPhotosAlbum(image,self,selector(imageSavedToPhotosAlbum:didFinishSavingWithError:contextInfo:),context); 5. UIGraphicsEndImageContext(); 6. 7. 8. /保存图片时的回调 9. -(void)imageSa