MP4 → WebP

Yambitsani mu wosewera, peza nthawi ndi kumbukirani nthawi ya nthawi, chifukwa MP4 siyimagwiritsa ntchito zilembo za kapitoli kuti mupite. Pezani kuti mu gawo la nthawi yoyamba, wonjezera nthawi yotenga, ndipo wosintha amafuna kumapeto kwa nthawiyo ndipo amachotsa malire omwe mwafunsidwa. Kufuna kumayenera ku frame, koma kumatha kukhala bwino ngati idadi yomwe imaperekedwa - onetsetsani kuti ndi yoyenera panthawi yoyamba ya kanemayo. MP4 amathandiza okha imodzi yotchuka subtitle mtundu (mov_text), ndi multi-traka audio ndi osati olimba m'malo desiki osewera.

A MP4 ndi fayilo ya ISO base-media, ndipo izi zitha kusinthidwa ngati chiwonetsero chazithunzi mu chotengera, osati posintha ma pixels - chifukwa chake clip yomwe ikugwiritsidwa ntchito mozungulira pafoni ikhoza kuwonekera m'modzi mwa osewera ndikukhala pambali pamodzi. Animation imapangidwa kuchokera ku pixels yosinthidwa, kuti chiwonetserocho chiyenera kuvomerezedwa pambuyo polemba chiwonetsero choyamba; ngati chithunzicho chimabwerera m'mbali, sinthani malo ochokera ndikusinthanso. Zonse zina za kamera kapena wolemba wolemba ndi nkhani yovuta: kanema wa kanema, mzere wokhazikika wa ma frame. Zikuoneka kuti pafupifupi aliyense MP4 m'munda ndi H.264 kanema ndi AAC audio; chidebenso mwalamulo ali HEVC, AV1 ndi VP9.

Yai, pamene muli ndi fayiloyo. A MP4 ndi zomwe webusaitiyi imagwiritsa ntchito kwa kanema wophatikizidwa chifukwa mabrowser amasewera popanda plugin, kotero clip yomwe imasewera mu tabu nthawi zambiri ndi MP4 yokhayo yomwe imasunga ndi kutsitsa pano monga fayilo ina iliyonse. Kulephera ndi wosewera wosewera yemwe amapatsa ma segments ofupi omwe amawerengedwa m'malo mwa fayilo imodzi - omwe ayenera kusinthidwanso pambuyo poti chilichonse chitha kusinthidwa. Malamulo ndi chinthu china chomwe chimayenera kutsimikiziridwa: kutsitsa kanema sichifanana ndi kuloledwa kufalitsanso animation yomwe idapangidwa kuchokera ku izo. MP4 ndi otetezeka zotheka kutumiza zolinga - aliyense foni, browser, console, wolemba ndi Smart TV anamanga mu zaka zapitazi amasewera izo popanda mapulogalamu atsopano.

Lossy, kwa chilichonse chomwe chimayamba ngati kanema. Animated WebP ingakongoletse ma frame ake mosiyana: mode ya lossless imasunga ma pixel onse ndi kugwirizana ndi zithunzi zopanda malire ndi mawu a pazenera, pomwe mode ya lossy imagwiritsa ntchito kuyembekezera kwa block-based monga momwe video codec imagwiritsa ntchito ndi kugwirizana ndi zithunzi zachilendo. Frames za kamera ndi zokhala ndi ma grains ndi gradients omwe lossless compression sapeza mzere, choncho animation ya lossless ya kanemayo imatha kuyendetsa nthawi zambiri kuposa ya lossy yomwe ikuwoneka ngati yofanana. Ikani ya lossy ngati kuti chiyambi chake chinali kujambula kwa skrini kwa mawu owoneka bwino. WebP ndibe yachiwiri-katundu kunja kwa browser — kusindikiza workflows, zaka zakale Office zomanga ndi ena foni galleries sakuvomereza izo.

Animated WebP imakula kwa ma clip pansi pa masekondi 10. Kutalika kuposa apo ndi ma baffles otsika kwambiri - GIF ndi opanda kulumikizana pa frame, kotero ngakhale ma clip otsika amayenda kwa ma megabytes ambiri. Kwa ma animations ochepa, tikufuna kulenga WebP kapena APNG, omwe amagwirizana ndi ma codecs amakono a video.

Kwa animated GIF pa 480p, zotsatira zofala ndi 2-8 MB kutengera kuthekera kwa kugwira ntchito. Kwa animated WebP pazomwezo / kudalirika, yembekezerani 200 KB mpaka 1 MB. Animated WebP ndi 5-10x yogwira ntchito bwino kuposa GIF pazomwezo. WebP amapatsa modes lossy ndi lossless, ndi alpha kuwala ndi animation alipo m'modzi kapena m'modzi.

Mwa default timalowetsa mpaka 15 fps kwa GIF yoanima (GIF imagwira ntchito mosakwanira pamwamba pa 25 fps m'mawonera ambiri) ndi 24 fps kwa WebP / APNG yoanima (yoyang'anira mitengo yotsika bwino). Chosankha cha frame-rate chimachotsa default kuti chiteteze mitengo yochokera ku MP4 yanu ngati wowonera wanu wosankhidwa akuthandizira.

Sichoncho - animated WebP mafomu (GIF, WebP, APNG) sasunga mawu panthawi iliyonse. Ngati mukufuna mawu ndi clip yanu, gwiritsani ntchito kanema wokhala ndi kanema (MP4, WebM, MKV) osati WebP. Masamba ambiri a bungwe (Twitter, Discord) amasintha kutsitsa kwa MP4 kukhala ma loops a GIF-style autoplay, ndikukupatsani zabwino zonse.

Ndikoyenera - njira yowerengera loop-count imawongolera ngati WebP imayenda mopanda malire (default), imasewera nthawi N, kapena imasewera kamodzi ndipo imatha. Kuwerengera kwa loop kusungira mu WebP metadata ya kontena ndipo imalemekeza aliyense woonera wamakono, webusaitiyi, ndi embed surface.

Zifukwa ziwiri zofala kwambiri: kuchepetsa kuchuluka kwa ma frame (timangochotsa 30 fps GIF MP4 mpaka 15 fps mwa default — timangosintha kuchuluka kwa ma frame kuti tibwezeretse kuwala) ndi kuwonjezera kwa palette (GIF imatha kujambula mpaka 256 za mitundu pa frame, zomwe zimasintha ma gradients mosiyana ndi momwe MP4 yoyamba inapangira).

Ndiyo — njira yosintha kukula imachepetsa kukula kwa kanemayo pambuyo pochotsa ma frame, zomwe zimachepetsa kwambiri kukula kwa final WebP. 480p WebP yopangidwa kuchokera ku 4K MP4 ndi 16x yaying'ono pa diski kuposa 4K WebP. Kudula kumachitika m'njira yosiyana ya /trim/ kapena /crop/ yothamanga pambuyo posintha.