PNG-nemanyorerwo features, application uye zvikonzero kukurumbira

Mumwe mukuru mabasa akatarirana Imposer nzvimbo itsva kutsanya vachizvitakudza mapeji browsers. Sezvo usingashandi zvakagadzirwa zvakafanana hazvisi vanoshandisa zvose kuva kuwana nekuyanana pakati yakaisvonaka akaitwa pamwe kwezvokufuka Graphics uye kumhanya web upfumi. Kare, kuti uderedze uremu zvifananidzo, kuti Developers nzvimbo inoshandiswa kana GIF, kana jpg. Zvino dzakawanda padandemutande vagadziri vanoshandisa mifananidzo PNG format. Pamwe chete, ngatiregei edza kunzwisisa nei zvose izvi zviri kuitika.

PNG-nemanyorerwo Sei rakatangwa

Chidimbu, ndiro zita iri mhando kudhirowa, aumba kubva tsamba inotevera Chirungu mashoko okutanga: ". Placeable Graphics yokushandisa pamusoro pemambure" inotakurika rezvebonde Graphics, iro rinogona kushandurwa sezvo PNG-nemanyorerwo kwave zvakananga mano kubvisa zvazvakashatira compression achishandisa nyore algorithm GIF, izvo zvishoma nezvishoma akatanga kuva usingachashandi. Uyezve, zvingava kusvika pamwero kushandiswa kutsiva zvikuru kura tiff, kushandiswa zvikurukuru fora.

Chii PNG-urongwa

Nhasi zvinowanzoshandiswa shanduro mbiri algorithm. In aimbova zvakafamba rinoshandisirwa munhu 8-yati ruvara palette, uye yechipiri - 24 wedzeredzei. Photos muna PNG-8 format, zvichienzaniswa GIF-shanduro siyanei nani compression reshiyo uye kushaya Kugona Animations. Pasinei chokwadi kuti vakadaro mifananidzo inogona ane vaifanira kubva 256 mavara, algorithm ichi rinoshandiswa zvikuru kuti pave graphical wenyaya, Logos, mifananidzo pamwe vakasiyana micheto uye mifananidzo pamwe gradient pachena. Muzviitiko apo izvi hazvina kukwana, Developers vanoshandisa 24-ikakuruma PNG-format, ine zvizhinji zvimwe zvikomborero, yakadai se:

• Mukuru compression algorithm, izvo zvinoderedza pasina chero kurasikirwa yepamusoro.
• Kugona kushandisa Alpha pachena rinopa 256 yakasiyana siyana pachena.
• Kuvapo wegamma kururamiswa, iyo yaibva chinja nokupenya mufananidzo apo achitamba muzvirongwa zvakasiyana.
• Kugona kushandisa anenge mamiriyoni 16.7 mavara.

izvi zvose zvinoita kuti chikumbiro pamwe PNG24 kuti compressing chero mifananidzo ine zvikamu segirazi vanodhirowa yakawanda ruvara uye unopinza micheto chacho.

budiriro muitiro

Pasinei chokwadi kuti kupararira PNG-youduku vachiri aparidze browsers vakura, uyewo rutsigiro kukwana uye kukwana pamusoro algorithm ichi zvinhu mushanduro itsva, PNG nokuti padandemutande Graphics ndiyo vaizotibata chaizvo. Tichienzanisa GIF ane mikuru zvakwakanakira zvitatu: imwe Arifa mugero, wegamma kururamiswa uye vaviri-dimensional interlacing (nzira mberi kuratidza mifananidzo). Uye ichienzaniswa jpeg risina kurasikirwa yepamusoro. Cherechedza kuti PNG-pamanyorerwo yakanga yakaitwa January 4, 1995. Kubvira ipapo makore 18 apfuura, uye akava kutungamirira kushandiswa mune Websites, GIF rokufurira munzvimbo yechipiri. Most tsika Graphics Software (semuenzaniso MS Paint) nhasi kushandisa nayo sechiero pakuponesa mafaira "ne default". Zvichida, kana asina kuchangamuka uye quirks vakwegura shanduro Internet Explorer, GIF kupa nzira aikwikwidza kwayo kwokutanga.