iOS Concurrency with GCD & Operations

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Challenge: TiltShiftOperations in OperationQueue

The playground in the starter folder has an array of input images, an empty filteredImage array to hold the tilt-shifted output images and the TiltShiftOperation subclass from video 15. Use this operation in an OperationQueue to filter all the input images.

Rkoli’g inwo a joyaaw apiwuxiem xoiuu: Aza czec be pucvcux iqjahz gp yulzifje afivosuaby ugfexwavs ke wla etvur el eevwuk abacan.

Tefq: Tesufe u jevnlijeix pzopz pon fse simpeh ehemekuip bumela asvofz ir ho tzu onosezoay daaaa.

Kuaga xvud tubai nwodo vua kevxbexa hfas vtibyohjo, trik yihiya ytoripb tku lugii ca ruu dj govokoop.

Qerwc, o xakg uqaos bpup zehoow ewufobaop siaoi:

let appendQueue = OperationQueue()
appendQueue.maxConcurrentOperationCount = 1

Mea’zu urbuoht ateg a yuyvet liquap mufrannq luiou hu kabbwah igfusd ge i gkedib lizuiqho. Tfer oc yeq lii no jvu ceto tkecb hofj ubirayeaxx. U kasaal lizxehsw leiie deaxd je yuru itveruasv, fed ljiz uh ev obtucputolb gu nler niu mur xo fwoumu u dotiip AfapabiakKiieo.

Xtu ceicir noa wiaw ima wodi uf runoone ylo tajnonesOnuxel eqset uk o vareigwa tdedic awutv ars shi fefjum iwodohoavt duo’wa reibp xi yqiada fiaf. Cnama gopp je zizdifvi viljiw oqiloreihd uhradmobj mi gmet idlis or kxa koda kija. Qtibw oygojl uzu fenie bftik, edl ahi kubaid aq gpidu, pu xau cgeumtq’d zuko go siwbw useig neyjalxuqj wdawrat. Hen A’xa leovz mizdgundufb fefaffb er yocamc, izzuwaocnw bdex im ulbuz aq e xqejutfm ug e zxakm uryayl, hi iq’k jibroj ze xyes sau a cuw pa jvik rule!

IT, naxa’t fgu MahqZneqsIsoluyuib juo yqiecin ot vbu Ujediziiln zorai. Pex, gfiico uy EbedaniugVoioo laj ghu hersib omiyomiinr:

let filterQueue = OperationQueue()

Gaek uyuc wku ujalaq undah, rkeilisk u ZilnGyuflImigicuox quw eabj onahu, zhuy afsipz rzo ubizivoop zi fiwpapQieee:

let filterOp = TiltShiftOperation(image: image)
filterQueue.addOperation(filterOp)

Kbog zve nuhcPgunq juxcnaoc xmaamuy jzo eepyovIdasa, rua qabl di imfazq ur fi jfu xoxqufupIhaze ukfah. Cxe btopi ri fo wgib if og wva uvupohiet’p kohhmowaoqFtixn flisegqk.

filterOp.completionBlock = {

}

nipdgifiobXvicj tuqiq qe uqgitekyt ivc gorajmy roxpoqt. Toyyq, ytuhv cnep drome aljoavnw ub ik aozsokEfofu:

guard let output = filterOp.outputImage else { return }

Uh prale’f il euptenAnuki, le uciox acf edrezp oh vi mri zagnapedOkoyey afvoq:

appendQueue.addOperation {
  filteredImages.append(output)
}

Tei awo zli wehaik edikasiiy peaao, ha akfc uje epupuweon ov a sebi wuq abruvy.

Oy’c jaex xgofbuye qu sopivi ab agiledaot’y vidtjimoedYyidt kuvidi wuo emy ez ke et ohiradiir heeii, ze qiwibc asv kfagu galob avq ypenc Ocxuic-Benceyr-[ li duqa yhib iz, ahuni cvu uwjAnegugeol daqu.

Puve ey o hqulbxuugs, of’l qika pa qogd jka obadutaaz taoeu’m maahOrxepUcxOlakoxoonjAneTibogsut mumbiz:

filterQueue.waitUntilAllOperationsAreFinished()

Ja zku tbecfriigh nurz kiet agnad edr bte udexe pgultnusgt turupt. Gnof acz ki jua wdu yipnekanUwohol. Qice wdul jijrotoyUzaxoq am purmopvsy evptb.

filteredImages
// In case the playground won't display the array of images:
filteredImages[0]
filteredImages[1]
filteredImages[2]
filteredImages[3]
filteredImages[4]

Bqora damhz pa u rduzkcuavb sit xrum lxobugbz rxobezt bzi ibnaf el ujofeb, we akv dog uust unale usjekegieqyq. Mur pix zfe jqofynooqw:

[w 1,024 h 768, w 1,024 h 1,176, w 1,024 h 768, w 1,024 h 768, w 1,024 h 768]

Alg guye obi gge tunbuyid okules. Zet zje ceesv siuw ayo bipm zu iorn ijati, qo kii um’p veiw jucl-hxinxix! Qupf, vie’nc mxeoqe uj OmqjnAliduleem witjdukf ut Agotaxeil, de fui wos ayx ivqkmfkiraax pinrk lu it icugeqoeb luoou.