ios - compress Size of Image without convert to NSData -


i have uicollectionview, in showing images downloading server. show these images using afnetworking class method setimagewithurl:(url*).

image size (968, 968) taking hell lot of memory. if convert these images nsdata , compressed uiimagejpegrepresentation method taking lot of time convert image nsdata. there way reduce size of images , show collection view cell without delay.

- (uiimage *)scaleandrotateimage:(uiimage *) image {   //resolution want int kmaxresolution = 1024;  cgimageref imgref = image.cgimage;  cgfloat width = cgimagegetwidth(imgref); cgfloat height = cgimagegetheight(imgref);   cgaffinetransform transform = cgaffinetransformidentity; cgrect bounds = cgrectmake(0, 0, width, height); if (width > kmaxresolution || height > kmaxresolution) {     cgfloat ratio = width/height;     if (ratio > 1) {         bounds.size.width = kmaxresolution;         bounds.size.height = bounds.size.width / ratio;     }     else {         bounds.size.height = kmaxresolution;         bounds.size.width = bounds.size.height * ratio;     } }  cgfloat scaleratio = bounds.size.width / width; cgsize imagesize = cgsizemake(cgimagegetwidth(imgref), cgimagegetheight(imgref)); cgfloat boundheight; uiimageorientation orient = image.imageorientation; switch(orient) {      case uiimageorientationup: //exif = 1         transform = cgaffinetransformidentity;         break;      case uiimageorientationupmirrored: //exif = 2         transform = cgaffinetransformmaketranslation(imagesize.width, 0.0);         transform = cgaffinetransformscale(transform, -1.0, 1.0);         break;      case uiimageorientationdown: //exif = 3         transform = cgaffinetransformmaketranslation(imagesize.width, imagesize.height);         transform = cgaffinetransformrotate(transform, m_pi);         break;      case uiimageorientationdownmirrored: //exif = 4         transform = cgaffinetransformmaketranslation(0.0, imagesize.height);         transform = cgaffinetransformscale(transform, 1.0, -1.0);         break;      case uiimageorientationleftmirrored: //exif = 5         boundheight = bounds.size.height;         bounds.size.height = bounds.size.width;         bounds.size.width = boundheight;         transform = cgaffinetransformmaketranslation(imagesize.height, imagesize.width);         transform = cgaffinetransformscale(transform, -1.0, 1.0);         transform = cgaffinetransformrotate(transform, 3.0 * m_pi / 2.0);         break;      case uiimageorientationleft: //exif = 6         boundheight = bounds.size.height;         bounds.size.height = bounds.size.width;         bounds.size.width = boundheight;         transform = cgaffinetransformmaketranslation(0.0, imagesize.width);         transform = cgaffinetransformrotate(transform, 3.0 * m_pi / 2.0);         break;      case uiimageorientationrightmirrored: //exif = 7         boundheight = bounds.size.height;         bounds.size.height = bounds.size.width;         bounds.size.width = boundheight;         transform = cgaffinetransformmakescale(-1.0, 1.0);         transform = cgaffinetransformrotate(transform, m_pi / 2.0);         break;      case uiimageorientationright: //exif = 8         boundheight = bounds.size.height;         bounds.size.height = bounds.size.width;         bounds.size.width = boundheight;         transform = cgaffinetransformmaketranslation(imagesize.height, 0.0);         transform = cgaffinetransformrotate(transform, m_pi / 2.0);         break;      default:         [nsexception raise:nsinternalinconsistencyexception format:@"invalid image orientation"];  }  uigraphicsbeginimagecontext(bounds.size);  cgcontextref context = uigraphicsgetcurrentcontext();  if (orient == uiimageorientationright || orient == uiimageorientationleft) {     cgcontextscalectm(context, -scaleratio, scaleratio);     cgcontexttranslatectm(context, -height, 0); } else {     cgcontextscalectm(context, scaleratio, -scaleratio);     cgcontexttranslatectm(context, 0, -height); }  cgcontextconcatctm(context, transform);  cgcontextdrawimage(uigraphicsgetcurrentcontext(), cgrectmake(0, 0, width, height), imgref); uiimage *imagecopy = uigraphicsgetimagefromcurrentimagecontext(); uigraphicsendimagecontext();  return imagecopy;

}


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