{"id":36133,"date":"2019-10-31T22:09:48","date_gmt":"2019-10-31T19:09:48","guid":{"rendered":"https:\/\/prohoster.info\/blog\/chitat-mezhdu-not-sistema-peredachi-dannyh-vnutri-muzyki\/"},"modified":"2019-10-31T22:09:48","modified_gmt":"2019-10-31T19:09:48","slug":"chitat-mezhdu-not-sistema-peredachi-dannyh-vnutri-muzyki","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/news\/chitat-mezhdu-not-sistema-peredachi-dannyh-vnutri-muzyki","title":{"rendered":"\u010c\u00edst mezi notami: syst\u00e9m p\u0159enosu dat v hudb\u011b","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

\"\u010c\u00edst
\n
\nVyj\u00e1d\u0159it to, co slova nedok\u00e1\u017eou p\u0159en\u00e9st; c\u00edtit rozmanit\u00e9 emoce propl\u00e9taj\u00edc\u00ed se v hurik\u00e1nu pocit\u016f; odtrhnout se od zem\u011b, nebe a dokonce i samotn\u00e9ho vesm\u00edru, vydat se na cestu, kde nejsou mapy, \u017e\u00e1dn\u00e9 silnice, \u017e\u00e1dn\u00e9 ukazatele; vymyslet, vypr\u00e1v\u011bt a pro\u017e\u00edt cel\u00fd p\u0159\u00edb\u011bh, kter\u00fd z\u016fstane nav\u017edy jedine\u010dn\u00fd a neopakovateln\u00fd. To v\u0161e umo\u017e\u0148uje hudba \u2014 um\u011bn\u00ed, kter\u00e9 existuje u\u017e tis\u00edce let a t\u011b\u0161\u00ed na\u0161e u\u0161i a srdce. <\/p>\n

Hudba, p\u0159esn\u011bji \u0159e\u010deno hudebn\u00ed skladby, v\u0161ak mohou slou\u017eit nejen pro estetick\u00e9 pot\u011b\u0161en\u00ed, ale tak\u00e9 pro p\u0159enos v nich zak\u00f3dovan\u00fdch informac\u00ed ur\u010den\u00fdch pro n\u011bjak\u00e9 za\u0159\u00edzen\u00ed a pro poslucha\u010de neviditeln\u00fdch. Dnes se sezn\u00e1m\u00edme s velmi neobvykl\u00fdm v\u00fdzkumem, ve kter\u00e9m dokto\u0159i z Cury\u0161sk\u00e9 vysok\u00e9 technick\u00e9 \u0161koly dok\u00e1zali nepozorovan\u011b pro lidsk\u00e9 ucho vlo\u017eit ur\u010dit\u00e9 \u00fadaje do hudebn\u00edch skladeb, \u010d\u00edm\u017e se hudba st\u00e1v\u00e1 kan\u00e1lem pro p\u0159enos dat. Jak p\u0159esn\u011b realizovali svou technologii, jak moc se melodie li\u0161\u00ed s a bez vlo\u017een\u00fdch dat a co uk\u00e1zaly praktick\u00e9 testy? O tom se dozv\u00edme v p\u0159edn\u00e1\u0161ce v\u00fdzkumn\u00edk\u016f. Jdeme na to.<\/a><\/noindex><\/p>\n

Z\u00e1klad v\u00fdzkumu<\/h3>\n

\nV\u00fdzkumn\u00edci naz\u00fdvaj\u00ed svou technologii akustickou technikou p\u0159enosu dat. Kdy\u017e reproduktor p\u0159ehr\u00e1v\u00e1 pozm\u011bn\u011bnou melodii, \u010dlov\u011bk ji vn\u00edm\u00e1 jako b\u011b\u017enou, zat\u00edmco nap\u0159\u00edklad chytr\u00fd telefon m\u016f\u017ee \u010d\u00edst zak\u00f3dovan\u00e9 informace mezi \u0159\u00e1dky, p\u0159esn\u011bji mezi notami, pokud to tak lze \u0159\u00edci. Nejd\u016fle\u017eit\u011bj\u0161\u00edm aspektem p\u0159i realizaci t\u00e9to metody p\u0159enosu dat v\u011bdci (to, \u017ee jsou st\u00e1le dokto\u0159i, jim nebr\u00e1n\u00ed b\u00fdt v\u011bdci) naz\u00fdvaj\u00ed rychlost a spolehlivost p\u0159enosu p\u0159i zachov\u00e1n\u00ed \u00farovn\u011b t\u011bchto parametr\u016f bez ohledu na vybran\u00fd audio soubor. S touto \u00falohou pom\u00e1h\u00e1 psychoakustika, kter\u00e1 zkoum\u00e1 psychologick\u00e9 a fyziologick\u00e9 aspekty vn\u00edm\u00e1n\u00ed zvuk\u016f \u010dlov\u011bkem. <\/p>\n

J\u00e1drem akustick\u00e9ho p\u0159enosu dat lze nazvat OFDM (multiplexov\u00e1n\u00ed s ortogon\u00e1ln\u00edm frekven\u010dn\u00edm d\u011blen\u00edm kan\u00e1l\u016f), kter\u00e9 spole\u010dn\u011b s adaptac\u00ed nosn\u00fdch frekvenc\u00ed na p\u016fvodn\u00ed hudbu v pr\u016fb\u011bhu \u010dasu umo\u017enilo maxim\u00e1ln\u011b vyu\u017e\u00edt spektrum p\u0159en\u00e1\u0161en\u00e9 frekvence pro p\u0159enos informac\u00ed. D\u00edky tomu se poda\u0159ilo dos\u00e1hnout p\u0159enosov\u00e9 rychlosti 412 bit\u016f\/s na vzd\u00e1lenost a\u017e 24 metr\u016f (koeficient chyb < 10 %). Praktick\u00e9 experimenty s \u00fa\u010dast\u00ed 40 dobrovoln\u00edk\u016f potvrdily, \u017ee je t\u00e9m\u011b\u0159 nemo\u017en\u00e9 rozli\u0161it mezi origin\u00e1ln\u00ed melodi\u00ed a tou, do kter\u00e9 byly vlo\u017eeny informace.<\/p>\n

Kde lze tuto technologii prakticky aplikovat? V\u00fdzkumn\u00edci maj\u00ed sv\u016fj vlastn\u00ed n\u00e1zor: t\u00e9m\u011b\u0159 v\u0161echny modern\u00ed smartphony, notebooky a dal\u0161\u00ed p\u0159enosn\u00e1 za\u0159\u00edzen\u00ed jsou vybavena mikrofony, a na mnoha ve\u0159ejn\u00fdch m\u00edstech (kav\u00e1rn\u00e1ch, restaurac\u00edch, obchodn\u00edch centrech atd.) jsou reproduktory s podkladovou hudbou. Do t\u00e9to podkladov\u00e9 melodie lze nap\u0159\u00edklad vlo\u017eit data pro p\u0159ipojen\u00ed k s\u00edti Wi-Fi bez nutnosti prov\u00e1d\u011bt dal\u0161\u00ed akce.<\/p>\n

Obecn\u00e9 rysy akustick\u00e9ho p\u0159enosu dat jsme si objasnili, nyn\u00ed p\u0159ejdeme k podrobn\u00e9mu zkoum\u00e1n\u00ed struktury tohoto syst\u00e9mu.<\/p>\n

Popis syst\u00e9mu<\/h3>\n

\nVkl\u00e1d\u00e1n\u00ed dat do melodie se prov\u00e1d\u00ed maskov\u00e1n\u00edm frekvence. V \u010dasov\u00fdch intervalech jsou identifikov\u00e1ny maskovac\u00ed frekvence a nosn\u00e9 OFDM, kter\u00e9 jsou bl\u00edzk\u00e9 t\u011bmto maskovac\u00edm prvk\u016fm, jsou vypln\u011bny daty.<\/p>\n

\"\u010c\u00edst
\nObr\u00e1zek \u010d. 1: p\u0159evod p\u016fvodn\u00edho souboru na kompozitn\u00ed sign\u00e1l (melodie + data), p\u0159en\u00e1\u0161en\u00fd p\u0159es reproduktory.<\/i><\/p>\n

Nejprve je p\u016fvodn\u00ed audio sign\u00e1l rozd\u011blen na sekven\u010dn\u00ed segmenty pro anal\u00fdzu. Ka\u017ed\u00fd takov\u00fd segment (Hi) o d\u00e9lce L = 8820 vzork\u016f, co\u017e odpov\u00edd\u00e1 200 ms, je vyn\u00e1soben oknem*<\/i> pro minimalizaci okrajov\u00fdch efekt\u016f.<\/p>\n

Okno*<\/b> je v\u00e1hov\u00e1 funkce pou\u017e\u00edvan\u00e1 k \u0159\u00edzen\u00ed efekt\u016f zp\u016fsoben\u00fdch p\u0159\u00edtomnost\u00ed bo\u010dn\u00edch lalok\u016f ve spektr\u00e1ln\u00edch odhadech.<\/p><\/blockquote>\n

D\u00e1le byly zji\u0161t\u011bny dominantn\u00ed frekvence p\u016fvodn\u00edho sign\u00e1lu v rozmez\u00ed od 500 Hz do 9,8 kHz, co\u017e umo\u017enilo z\u00edskat maskuj\u00edc\u00ed frekvence fM,l pro dan\u00fd segment. Krom\u011b toho se prov\u00e1d\u011bl p\u0159enos dat v mal\u00e9m rozsahu od 9,8 do 10 kHz pro ur\u010den\u00ed polohy podnosn\u00fdch frekvenc\u00ed v p\u0159ij\u00edma\u010di. Horn\u00ed hranice pou\u017eit\u00e9 oblasti frekvenc\u00ed byla stanovena na 10 kHz kv\u016fli n\u00edzk\u00e9 citlivosti mikrofon\u016f chytr\u00fdch telefon\u016f na vysok\u00e9 frekvence.<\/p>\n

Maskuj\u00edc\u00ed frekvence byly ur\u010deny pro ka\u017ed\u00fd analyzovan\u00fd segment individu\u00e1ln\u011b. Pomoc\u00ed metody HPS (harmonick\u00e9ho spektra produkt\u016f) byly stanoveny t\u0159i dominantn\u00ed frekvence, kter\u00e9 byly pot\u00e9 zaokrouleny na nejbli\u017e\u0161\u00ed noty harmonick\u00e9 chromatick\u00e9 \u0161k\u00e1ly. Tak byly z\u00edsk\u00e1ny z\u00e1kladn\u00ed noty fF,i = 1\u20263, kter\u00e9 le\u017e\u00ed mezi kl\u00e1vesami C0 (16,35 Hz) a B0 (30,87 Hz). Vzhledem k tomu, \u017ee z\u00e1kladn\u00ed noty jsou p\u0159\u00edli\u0161 n\u00edzk\u00e9 pro pou\u017eit\u00ed p\u0159i p\u0159enosu dat, byly v rozmez\u00ed 500 Hz \u2026 9,8 kHz vypo\u010d\u00edt\u00e1ny jejich vy\u0161\u0161\u00ed okt\u00e1vy 2kfF,i. Mnoh\u00e9 z t\u011bchto frekvenc\u00ed (fO,l1) byly v\u00edce v\u00fdrazn\u00e9 d\u00edky povaze HPS.<\/p>\n

\"\u010c\u00edst
\nObr\u00e1zek \u010d. 2: vypo\u010d\u00edtan\u00e9 okt\u00e1vy fO,l1 pro z\u00e1kladn\u00ed noty a harmoniky fH,l2 nejsiln\u011bj\u0161\u00edho t\u00f3nu.<\/i><\/p>\n

Soubor okt\u00e1v a harmonik byl nakonec vyu\u017eit jako maskuj\u00edc\u00ed frekvence, na jejich\u017e z\u00e1klad\u011b byly z\u00edsk\u00e1ny frekvence OFDM podnosn\u00e9 fSC,k. Nad a pod ka\u017edou maskuj\u00edc\u00ed frekvenc\u00ed byly vlo\u017eeny dv\u011b podnosn\u00e9. <\/p>\n

D\u00e1le doch\u00e1zelo k filtrov\u00e1n\u00ed spektra audioklipu Hi na frekvenc\u00edch podnosn\u00fdch fSC,k. Na z\u00e1klad\u011b informa\u010dn\u00edch bit\u016f v Bi byl vytvo\u0159en OFDM symbol, d\u00edky \u010demu\u017e mohl b\u00fdt kompozitn\u00ed segment Ci p\u0159en\u00e1\u0161en p\u0159es reproduktor. Hodnoty a f\u00e1ze podnosn\u00fdch je t\u0159eba zvolit tak, aby p\u0159ij\u00edma\u010d mohl extrahovat p\u0159enesen\u00e1 data, zat\u00edmco poslucha\u010d si nev\u0161iml zm\u011bn v melodii.<\/p>\n

\"\u010c\u00edst
\nObr\u00e1zek \u010d. 3: \u00fasek spektra a frekvence podnosn\u00fdch segmentu Hi p\u016fvodn\u00ed melodie.<\/i><\/p>\n

Kdy\u017e je audio sign\u00e1l, kter\u00fd obsahuje zak\u00f3dovan\u00e9 informace, p\u0159ehr\u00e1v\u00e1n p\u0159es reproduktory, mikrofon p\u0159ij\u00edmac\u00edho za\u0159\u00edzen\u00ed ho zaznamen\u00e1. Aby se na\u0161ly po\u010d\u00e1te\u010dn\u00ed pozice zakomponovan\u00fdch OFDM symbol\u016f, mus\u00ed b\u00fdt z\u00e1znam nejprve zpracov\u00e1n p\u0159es p\u00e1smov\u00e9 filtry. T\u00edmto zp\u016fsobem se extrahuje horn\u00ed frekven\u010dn\u00ed p\u00e1smo, kde nejsou hudebn\u00ed sign\u00e1ly-interference mezi podnosn\u00fdmi vlnami. Po\u010d\u00e1tek OFDM symbol\u016f lze nal\u00e9zt pomoc\u00ed cyklick\u00e9ho prefixu.<\/p>\n

Po detekci za\u010d\u00e1tku OFDM symbol\u016f p\u0159ij\u00edma\u010d z\u00edsk\u00e1v\u00e1 informace o nejdominantn\u011bj\u0161\u00edch t\u00f3nech prost\u0159ednictv\u00edm dek\u00f3dov\u00e1n\u00ed horn\u00ed frekven\u010dn\u00ed oblasti. OFDM je tak\u00e9 dostate\u010dn\u011b odoln\u00fd v\u016f\u010di zdroj\u016fm \u00fazkop\u00e1smov\u00fdch interferenc\u00ed, proto\u017ee ty ovliv\u0148uj\u00ed pouze n\u011bkter\u00e9 z podnosn\u00fdch vln.<\/p>\n

Praktick\u00e9 testy<\/h3>\n

\nJako zdroj pozm\u011bn\u011bn\u00fdch melodi\u00ed byl pou\u017eit reproduktor KRK Rokit 8 a p\u0159ij\u00edmaj\u00edc\u00ed stranou byl smartphone Nexus 5X.<\/p>\n

\"\u010c\u00edst
\nObr\u00e1zek \u010d. 4: rozd\u00edl mezi skute\u010dn\u00fdmi projevem OFDM a vrcholy korelace zm\u011b\u0159en\u00fdmi v m\u00edstnosti na vzd\u00e1lenost 5 m mezi reproduktorem a mikrofonem.<\/i><\/p>\n

V\u011bt\u0161ina OFDM bod\u016f le\u017e\u00ed v rozmez\u00ed od 0 do 25 ms, a proto lze nal\u00e9zt p\u0159\u00edpustn\u00fd po\u010d\u00e1tek v r\u00e1mci cyklick\u00e9ho prefixu 66,6 ms. V\u00fdzkumn\u00edci poznamen\u00e1vaj\u00ed, \u017ee p\u0159ij\u00edma\u010d (v tomto experimentu smartphone) bere v \u00favahu, \u017ee OFDM symboly jsou reprodukov\u00e1ny periodicky, co\u017e zlep\u0161uje jejich detekci.<\/p>\n

Prvn\u00ed, co bylo t\u0159eba ov\u011b\u0159it, byl vliv vzd\u00e1lenosti na m\u00edru chyb po bitech (BER). K tomu byly provedeny t\u0159i testy v r\u016fzn\u00fdch typech m\u00edstnost\u00ed: chodb\u011b s koberci, kancel\u00e1\u0159i s linoleem na podlaze a posluch\u00e1rn\u011b s d\u0159ev\u011bnou podlahou.<\/p>\n

\r\n \"P\u0159ehr\u00e1t\r\n
<\/div>\r\n <\/div><\/center>
\nZa \"testovan\u00fd\" byl vybr\u00e1n hit \"And The Cradle Will Rock\" od skupiny Van Halen. <\/i><\/p>\n

Hlasitost byla nastavena tak, aby m\u011b\u0159en\u00fd smartphone na vzd\u00e1lenost 2 m od reproduktoru vykazoval \u00farove\u0148 zvuku 63 dB.<\/p>\n

\"\u010c\u00edst
\nObr\u00e1zek \u010d. 5: ukazatele BER v z\u00e1vislosti na vzd\u00e1lenosti mezi reproduktorem a mikrofonem (modr\u00e1 linie \u2014 posluch\u00e1rna, zelen\u00e1 \u2014 chodba, oran\u017eov\u00e1 \u2014 kancel\u00e1\u0159).<\/i><\/p>\n

Na chodb\u011b byl zvuk o \u00farovni 40 dB zachycen smartphone na vzd\u00e1lenost a\u017e 24 metr\u016f od reproduktoru. V posluch\u00e1rn\u011b na vzd\u00e1lenost 15 m byl zvuk 55 dB, zat\u00edmco v kancel\u00e1\u0159i, kde byla vzd\u00e1lenost 8 m, \u00farove\u0148 zvuku dosahovala 57 dB. <\/p>\n

Vzhledem k tomu, \u017ee publikum a kancel\u00e1\u0159 jsou v\u00edce reverberuj\u00edc\u00ed, pozdn\u00ed echo sign\u00e1ly OFDM symbol\u016f p\u0159ekra\u010duj\u00ed d\u00e9lku cyklick\u00e9ho prefixu a zvy\u0161uj\u00ed BER.<\/p>\n

Reverberace*<\/b> \u2014 postupn\u00e9 sni\u017eov\u00e1n\u00ed intenzity zvuku v d\u016fsledku jeho opakovan\u00e9ho odrazu. <\/p><\/blockquote>\n

D\u00e1le v\u00fdzkumn\u00edci demonstrovali univerz\u00e1lnost sv\u00e9ho syst\u00e9mu, aplikovali ho na 6 r\u016fzn\u00fdch p\u00edsn\u00ed t\u0159\u00ed \u017e\u00e1nr\u016f (tabulka n\u00ed\u017ee).<\/p>\n

\"\u010c\u00edst
\nTabulka \u010d. 1: pou\u017eit\u00e9 p\u00edsn\u011b v testech.<\/i><\/p>\n

Tak\u00e9 pomoc\u00ed \u00fadaj\u016f z tabulky m\u016f\u017eeme vid\u011bt p\u0159enosovou rychlost a chybovost bit\u016f pro ka\u017edou p\u00edse\u0148. P\u0159enosov\u00e1 rychlost se li\u0161\u00ed, proto\u017ee diferenci\u00e1ln\u00ed BPSK (f\u00e1zov\u00e1 modulace) funguje l\u00e9pe, kdy\u017e se pou\u017e\u00edvaj\u00ed stejn\u00e9 podnosn\u00e9. To je mo\u017en\u00e9, kdy\u017e sousedn\u00ed segmenty obsahuj\u00ed stejn\u00e9 maskovac\u00ed prvky. Kontinu\u00e1ln\u011b hlasit\u00e9 p\u00edsn\u011b poskytuj\u00ed optim\u00e1ln\u00ed z\u00e1kladnu pro skryt\u00ed dat, proto\u017ee maskovac\u00ed frekvence jsou v\u00fdrazn\u011bji p\u0159\u00edtomny v \u0161irok\u00e9m frekven\u010dn\u00edm spektru. Rychle se m\u011bn\u00edc\u00ed hudba m\u016f\u017ee \u010d\u00e1ste\u010dn\u011b maskovat OFDM symboly kv\u016fli pevn\u00e9 d\u00e9lce analytick\u00e9ho okna.<\/p>\n

D\u00e1le se testov\u00e1n\u00ed syst\u00e9mu z\u00fa\u010dastnili lid\u00e9, kte\u0159\u00ed m\u011bli ur\u010dit, kter\u00e1 melodie je origin\u00e1ln\u00ed a kter\u00e1 byla modifikov\u00e1na vlo\u017eenou informac\u00ed. K tomu byly na speci\u00e1ln\u00edm webu um\u00edst\u011bny 12sekundov\u00e9 \u00faryvky p\u00edsn\u00ed z tabulky \u010d. 1. <\/p>\n

V prvn\u00edm experimentu (E1) byl ka\u017ed\u00e9mu \u00fa\u010dastn\u00edkovi poskytnut bu\u010f zm\u011bn\u011bn\u00fd, nebo origin\u00e1ln\u00ed \u00faryvek k poslechu, a m\u011bl rozhodnout, zda je tento \u00faryvek origin\u00e1ln\u00ed nebo pozm\u011bn\u011bn\u00fd. Ve druh\u00e9m experimentu (E2) mohli \u00fa\u010dastn\u00edci poslouchat oba varianty neomezen\u011b, a pot\u00e9 rozhodnout, kter\u00fd z nich je origin\u00e1l a kter\u00fd byl zm\u011bn\u011bn.<\/p>\n

\"\u010c\u00edst
\nTabulka \u010d. 2: v\u00fdsledky experiment\u016f E1 a E2.<\/i><\/p>\n

Ve v\u00fdsledc\u00edch prvn\u00edho experimentu jsou dva ukazatele: p(O|O) \u2014 procento \u00fa\u010dastn\u00edk\u016f, kte\u0159\u00ed spr\u00e1vn\u011b ozna\u010dili p\u016fvodn\u00ed melodii a p(O|M) \u2014 procento \u00fa\u010dastn\u00edk\u016f, kte\u0159\u00ed ozna\u010dili pozm\u011bn\u011bnou verzi melodie jako origin\u00e1ln\u00ed.<\/p>\n

Zaj\u00edmav\u00e9 je, \u017ee n\u011bkte\u0159\u00ed \u00fa\u010dastn\u00edci, podle v\u00fdzkumn\u00edk\u016f, pova\u017eovali ur\u010dit\u00e9 modifikovan\u00e9 melodie za origin\u00e1ln\u011bj\u0161\u00ed ne\u017e samotn\u00fd origin\u00e1l. Pr\u016fm\u011br v\u00fdsledk\u016f obou experiment\u016f nazna\u010duje, \u017ee pr\u016fm\u011brn\u00fd poslucha\u010d si nev\u0161imne rozd\u00edlu mezi b\u011b\u017enou melodi\u00ed a tou, do kter\u00e9 byla data vlo\u017eena.<\/p>\n

Samoz\u0159ejm\u011b, znalci hudby a hudebn\u00edci mohou zachytit ur\u010dit\u00e9 nep\u0159esnosti a podez\u0159el\u00e9 prvky v modifikovan\u00fdch melodi\u00edch, ale tyto prvky nejsou natolik v\u00fdznamn\u00e9, aby zp\u016fsobovaly nepohodl\u00ed.<\/p>\n

A te\u010f se m\u016f\u017eeme z\u00fa\u010dastnit experimentu. N\u00ed\u017ee jsou uvedeny dv\u011b verze t\u00e9\u017ee melodie \u2014 origin\u00e1ln\u00ed a modifikovan\u00e1. Sly\u0161\u00edte rozd\u00edl?<\/p>\n

Origin\u00e1ln\u00ed verze melodie<\/a><\/noindex>
\nvs
\nModifikovan\u00e1 verze melodie<\/a><\/noindex><\/p>\n

Pro podrobn\u011bj\u0161\u00ed sezn\u00e1men\u00ed se s nuancemi v\u00fdzkumu doporu\u010duji nahl\u00e9dnout do prezentace<\/a><\/noindex> v\u00fdzkumn\u00e9 skupiny.<\/p>\n

Tak\u00e9 si m\u016f\u017eete st\u00e1hnout ZIP archiv audio soubor\u016f origin\u00e1ln\u00edch a modifikovan\u00fdch melodi\u00ed, kter\u00e9 byly pou\u017eity ve v\u00fdzkumu, na tento odkaz<\/a><\/noindex>.<\/p>\n

Epilog<\/h3>\n

\nV t\u00e9to pr\u00e1ci popisuj\u00ed doktorandi \u0161v\u00fdcarsk\u00e9 vysok\u00e9 technick\u00e9 \u0161koly v Curychu \u00fa\u017easn\u00fd syst\u00e9m p\u0159enosu dat uvnit\u0159 hudby. K tomu pou\u017eili frekvencov\u00e9 maskov\u00e1n\u00ed, co\u017e umo\u017enilo v\u010dlenit data do melodie p\u0159ehr\u00e1van\u00e9 reproduktorem. Tato melodie je zachycena mikrofonem za\u0159\u00edzen\u00ed, kter\u00e9 rozpozn\u00e1v\u00e1 skryt\u00e1 data a dek\u00f3duje je, zat\u00edmco pr\u016fm\u011brn\u00fd poslucha\u010d rozd\u00edlu ani nepov\u0161imne. V budoucnu pl\u00e1nuj\u00ed v\u00fdvoj sv\u00e9ho syst\u00e9mu, aby na\u0161li sofistikovan\u011bj\u0161\u00ed metody pro vkl\u00e1d\u00e1n\u00ed dat do zvuku. <\/p>\n

Kdy\u017e n\u011bkdo vymysl\u00ed n\u011bco neobvykl\u00e9ho, a co je d\u016fle\u017eit\u011bj\u0161\u00ed, funk\u010dn\u00edho, v\u017edy n\u00e1s to pot\u011b\u0161\u00ed. Ale je\u0161t\u011b v\u00edce n\u00e1s t\u011b\u0161\u00ed, \u017ee tento vyn\u00e1lez vytvo\u0159ili mlad\u00ed lid\u00e9. V\u011bda nem\u00e1 v\u011bkov\u00e9 omezen\u00ed. A pokud ml\u00e1de\u017e pova\u017euje v\u011bdu za nudnou, znamen\u00e1 to, \u017ee nen\u00ed prezentov\u00e1na t\u00edm spr\u00e1vn\u00fdm zp\u016fsobem. Jak v\u00edme, v\u011bda je \u00fa\u017easn\u00fd sv\u011bt, kter\u00fd n\u00e1s nikdy nep\u0159estane p\u0159ekvapovat. <\/p>\n

P\u00e1te\u010dn\u00ed off-topic:<\/b>

\r\n \"P\u0159ehr\u00e1t\r\n
<\/div>\r\n <\/div><\/center>
\nA kdy\u017e u\u017e jsme hovo\u0159ili o hudb\u011b, konkr\u00e9tn\u011b o rockov\u00e9 hudb\u011b, zde je skv\u011bl\u00e1 cesta po sv\u011bt\u011b rocku.<\/i><\/p>\n

\r\n \"P\u0159ehr\u00e1t\r\n
<\/div>\r\n <\/div><\/center>
\nQueen, \u201eRadio Ga Ga\u201c (1984).<\/i><\/p>\n

D\u011bkuji za pozornost, z\u016fsta\u0148te zv\u00eddav\u00ed a m\u011bjte skv\u011bl\u00fd v\u00edkend, kluci! \ud83d\ude42<\/p>\n

\nD\u011bkujeme, \u017ee s n\u00e1mi z\u016fst\u00e1v\u00e1te. L\u00edb\u00ed se v\u00e1m na\u0161e \u010dl\u00e1nky? Chcete vid\u011bt v\u00edce zaj\u00edmav\u00fdch materi\u00e1l\u016f? Podpo\u0159te n\u00e1s objedn\u00e1vkou nebo doporu\u010den\u00edm zn\u00e1m\u00fdm, 30 % sleva pro u\u017eivatele Habra na jedine\u010dn\u00fd analog entry-level server\u016f, kter\u00fd jsme pro v\u00e1s vymysleli:<\/b> Ve\u0161ker\u00e1 pravda o VPS (KVM) E5-2650 v4 (6 jader) 10GB DDR4 240GB SSD 1Gbps od 20 $ nebo jak spr\u00e1vn\u011b rozd\u011blit server?<\/a><\/noindex> (k dispozici varianty s RAID1 a RAID10, a\u017e 24 jader a a\u017e 40GB DDR4).<\/p>\n

Dell R730xd za polovinu ceny?<\/b> Jen u n\u00e1s 2 x Intel TetraDeca-Core Xeon 2x E5-2697v3 2.6GHz 14C 64GB DDR4 4x960GB SSD 1Gbps 100 TB od 199 $<\/a><\/noindex> v Nizozemsku! Dell R420 \u2014 2x E5-2430 2.2GHz 6C 128GB DDR3 2x960GB SSD 1Gbps 100TB \u2014 od 99 $!<\/b><\/b> \u010ct\u011bte o tom Jak postavit infrastrukturu podnikov\u00e9 t\u0159\u00eddy s pou\u017eit\u00edm server\u016f Dell R730xd E5-2650 v4 v hodnot\u011b 9000 eur za pakatel?<\/a><\/noindex>
\n
Zdroj: habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0412\u044b\u0441\u043a\u0430\u0437\u0430\u0442\u044c \u0442\u043e, \u0447\u0442\u043e \u0441\u043b\u043e\u0432\u0430 \u043d\u0435 \u043c\u043e\u0433\u0443\u0442 \u043f\u0435\u0440\u0435\u0434\u0430\u0442\u044c; \u043f\u043e\u0447\u0443\u0432\u0441\u0442\u0432\u043e\u0432\u0430\u0442\u044c \u0441\u0430\u043c\u044b\u0435 \u0440\u0430\u0437\u043d\u043e\u043e\u0431\u0440\u0430\u0437\u043d\u044b\u0435 \u044d\u043c\u043e\u0446\u0438\u0438, \u043f\u0435\u0440\u0435\u043f\u043b\u0435\u0442\u0430\u044e\u0449\u0438\u0435\u0441\u044f \u0432 \u0443\u0440\u0430\u0433\u0430\u043d \u0447\u0443\u0432\u0441\u0442\u0432; \u043e\u0442\u043e\u0440\u0432\u0430\u0442\u044c\u0441\u044f \u043e\u0442 \u0437\u0435\u043c\u043b\u0438, \u043d\u0435\u0431\u0430 \u0438 \u0434\u0430\u0436\u0435 \u0441\u0430\u043c\u043e\u0439 \u0412\u0441\u0435\u043b\u0435\u043d\u043d\u043e\u0439, \u043e\u0442\u043f\u0440\u0430\u0432\u0438\u0432\u0448\u0438\u0441\u044c \u0432 \u043f\u0443\u0442\u0435\u0448\u0435\u0441\u0442\u0432\u0438\u0435, \u0433\u0434\u0435 \u043d\u0435\u0442 \u043a\u0430\u0440\u0442, \u043d\u0435\u0442 \u0434\u043e\u0440\u043e\u0433, \u043d\u0435\u0442 \u0443\u043a\u0430\u0437\u0430\u0442\u0435\u043b\u0435\u0439; \u043f\u0440\u0438\u0434\u0443\u043c\u0430\u0442\u044c, \u0440\u0430\u0441\u0441\u043a\u0430\u0437\u0430\u0442\u044c \u0438 \u043f\u0435\u0440\u0435\u0436\u0438\u0442\u044c \u0446\u0435\u043b\u0443\u044e \u0438\u0441\u0442\u043e\u0440\u0438\u044e, \u043a\u043e\u0442\u043e\u0440\u0430\u044f \u0432\u0441\u0435\u0433\u0434\u0430 \u043e\u0441\u0442\u0430\u043d\u0435\u0442\u0441\u044f \u0443\u043d\u0438\u043a\u0430\u043b\u044c\u043d\u043e\u0439 \u0438 \u043d\u0435\u043f\u043e\u0432\u0442\u043e\u0440\u0438\u043c\u043e\u0439. \u0412\u0441\u0435 \u044d\u0442\u043e \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u0435\u0442 \u0441\u0434\u0435\u043b\u0430\u0442\u044c \u043c\u0443\u0437\u044b\u043a\u0430 \u2014 \u0438\u0441\u043a\u0443\u0441\u0441\u0442\u0432\u043e, \u0441\u0443\u0449\u0435\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u0435 \u0443\u0436\u0435 \u043c\u043d\u043e\u0433\u0438\u0435 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":27023,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-36133","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47 \u010c\u00edst mezi notami: syst\u00e9m p\u0159enosu dat uvnit\u0159 hudby | ProHoster","description":"Vyj\u00e1d\u0159it to, co slova nemohou.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/news\/chitat-mezhdu-not-sistema-peredachi-dannyh-vnutri-muzyki","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"cs_CZ","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u0427\u0438\u0442\u0430\u0442\u044c \u043c\u0435\u0436\u0434\u0443 \u043d\u043e\u0442: \u0441\u0438\u0441\u0442\u0435\u043c\u0430 \u043f\u0435\u0440\u0435\u0434\u0430\u0447\u0438 \u0434\u0430\u043d\u043d\u044b\u0445 \u0432\u043d\u0443\u0442\u0440\u0438 \u043c\u0443\u0437\u044b\u043a\u0438 | ProHoster","og:description":"\u0412\u044b\u0441\u043a\u0430\u0437\u0430\u0442\u044c \u0442\u043e, \u0447\u0442\u043e \u0441\u043b\u043e\u0432\u0430 \u043d\u0435 \u043c\u043e\u0433\u0443\u0442.","og:url":"https:\/\/prohoster.info\/cs\/blog\/news\/chitat-mezhdu-not-sistema-peredachi-dannyh-vnutri-muzyki","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2019-10-31T19:09:48+00:00","article:modified_time":"2019-10-31T19:09:48+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"36133","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":null,"schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"seo_analyzer_scan_date":"2026-01-22 02:08:19","breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2021-03-01 01:50:23","updated":"2026-01-22 02:08:19","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/36133","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=36133"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/36133\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media\/27023"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=36133"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=36133"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=36133"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}