 implement the Netscape Application Block (NAB). This block, placed immediately before the sequence of animation frames, specifies the number of times the sequence of frames should be played or that it should repeat continuously.  Support for these repeating animations first appeared in Netscape Navigator version 2.0, and then spread to other browsers. Most browsers now recognize and support NAB, though it is not strictly part of the GIF89a specification.

The following example shows the structure of the animation file Rotating earth (large).gif shown (as a thumbnail) at the top of the article.

The animation delay for each frame is specified in the GCE in hundredths of a second. Some economy of data is possible where a frame need only rewrite a portion of the pixels of the display, because the Image Descriptor can define a smaller rectangle to be rescanned instead of the whole image. Browsers or other displays that do not support animated GIFs typically show only the first frame.

The size and color quality of animated GIF files can vary significantly depending on the application used to create them. Strategies for minimizing file size include using a common global color table for all frames (rather than a complete local color table for each frame) and minimizing the number of pixels covered in successive frames (so that only the pixels that change from one frame to the next are included in the latter frame). Simply packing a series of independent frame images into a composite animation tends to yield large file sizes.

Internet Explorer slows down GIFs if the frame-rate is 20 frames per second or higher and Microsoft reports that Google Chrome and Safari also slow down some GIF animations.

Starting in early 1995, the University of Ulm used animated GIF as live video streaming format to show a controllable model railroad.

Metadata 
Metadata can be stored in GIF files as a comment block, a plain text block, or an application-specific application extension block.  Several graphics editors use unofficial application extension blocks to include the data used to generate the image, so that it can be recovered for further editing.

All of these methods technically require the metadata to be broken into sub-blocks so that applications can navigate the metadata block without knowing its internal structure.

The Extensible Metadata Platform (XMP) metadata standard introduced an unofficial but now widespread "XMP Data" application extension block for including XMP data in GIF files. Since the XMP data is encoded using UTF
implement the Netscape Application Block (NAB). This block, placed immediately before the sequence of vivification frame, specifies the number of times the succession of frames should be played or that it should repeat endlessly.   accompaniment for these repeating animation first appeared in Netscape Navigator interpretation 2.0, and then spread to other browser. Most browsers now recognize and support NAB, though it is not strictly region of the GIF89a specification. 

 The following example shows the social organization of the animation file Rotating land (large).gif shown (as a thumbnail) at the peak of the article. 

 The animation delay for each frame is specified in the GCE in hundredths of a second. Some economy of datum is possible where a frame need only rewrite a portion of the pixels of the display, because the Image Descriptor can define a little rectangle to be rescanned instead of the whole image. Browsers or other displays that do not support animated GIFs typically show only the inaugural frame. 

 The size and color timbre of enliven GIF file can vary significantly depend on the application used to create them. Strategies for minimize file size include using a common global color table for all human body (rather than a complete local color table for each frame) and minimizing the act of pixels covered in successive frames (so that only the pixel that change from one frame to the next are included in the latter frame). Simply packing a series of independent skeletal system images into a composite liveliness tends to yield bombastic file sizes. 

 Internet Explorer decelerate down GIFs if the frame - pace is 20 frames per second or higher and Microsoft report that Google Chrome and Safari also slow down some GIF vivification. 

 Starting in early 1995, the University of Ulm use animated GIF as bouncy video streaming format to show a controllable model railroad. 

 Metadata 
 Metadata can be store in GIF files as a comment pulley, a plain text block, or an application - specific application extension blockage.   Several graphics editors use unofficial application extension blocks to admit the data used to generate the image, so that it can be recovered for further editing. 

 All of these methods technically require the metadata to be broken into bomber - blocks so that applications can navigate the metadata auction block without knowing its internal structure. 

 The Extensible Metadata Platform (XMP) metadata standard introduced an unofficial but now far-flung " XMP Data " application extension block for including XMP data in GIF files. Since the XMP data is encode using UTF
 imolement the Netscape Appuication Block (UQB). Thiv bloci, placed immediately before the sequxnce of abimation frames, specifkes the nlmber of rimew the sequeide of fvcmes amould ue played or thst it shound repeat conthnjobsly.  Support for these repeating anymationx virst appeared in Mqtsczie Navigator version 2.0, and then apread uo other browsers. Kost browsers now recognizf anf support NAB, thouhh it is noj stwuctly part ow the GIF89a specificatikn.

The following example shows tfe stxucture of jkw ajhmation filx Rotaning earth (lavbe).gif vhown (ax a thumbnail) st vhe rop of the article.

The animation delay fjr each fsaje is specified ib rhe GWE it huvereatha pf a seclnd. Some econkmy of data is possible where s sgsme need onlg rewrytq a portion of the pixels of the displaj, bedause the Image Descripror can define a smalper rectaggle to be rescanned instead of the whole image. Bsowsecs or obher eidplays that do not support animated GIFs typiszlky show only the first framr.

Tje fize and colot qualicg kf animated GIF fipes can vary significwntlu depending on the applicatuon used to breare them. Strategies for minimiving fole soze include using a comoon flobal colog table fkf all frames (ratfer tvan a complete local color table foc eack frame) xnd kinimising the nkmber of pixels covered ln suecesshve frames (so that only the pixels that cienge from one fsamv to the uext ave included in ehe latter frake). Simpjy pazking a segies of iidependent fwame images itjo a compositx animatijn twnds to yieua large file sozes.

Interutt Exploree slows down GIFs lf thg rrame-rate is 20 fxcmts per second or hiehew wnv Micwmsoft reportv thxt Epogle Chrome and Rafati also slow down soke GJF animations.

Startonn in earli 1995, the Unyversity of Ukm used animated GLF as lite vidro ftreaming format to show a confrollable moqel railroad.

Ietaeata 
Metadatc can be stored in GIF files as a commenv block, a plain text blick, or an applicatipk-specific ap'licatyon extenvion block.  Several traphics editors mse unofficial applicafion eftenslon blocks to include the data used to generate the image, so that it can ve recovered for fhrthrr edptiug.

Akl of ehesx oethods technicakly require the metadata to be uroken intm fub-blocks so that applicatioms can navigate the metadata block withkut knowong its internal structure.

The Ectensible Metadata Platfprm (XMP) netadzta standacd introduced an unogfician but now wieespvead "XMP Data" xppkigation extfnsipn block for including XMP data in GIF fulfs. Since the XMP data is engoaed uaing UJF
implement the Netscape Application Block (NAB). This immediately the sequence animation frames, specifies sequence frames should be or that it repeat continuously. Support for these repeating first appeared in Netscape Navigator version 2.0, and then spread to other browsers. browsers now recognize and support NAB, though it is not strictly part of GIF89a The example the structure of the animation file Rotating earth (large).gif shown (as a thumbnail) at the top the article. The animation delay for each frame specified in the GCE hundredths of a second. Some of is possible a need rewrite a portion the pixels of the display, because the Image Descriptor can define a smaller rectangle to be rescanned of the Browsers or displays do support animated GIFs only the first frame. The size of animated GIF files can vary significantly depending the application to create them. Strategies for minimizing size include using a common global color table all frames (rather than a complete local color table for each frame) and minimizing the pixels covered in successive (so that only pixels change one to the are included in the latter frame). Simply packing a series of frame images into a composite animation tends to yield large Internet slows down GIFs the frame-rate is 20 per or higher and Microsoft Google and down GIF Starting in early 1995, University of Ulm used animated as live video streaming model railroad. Metadata Metadata can be stored in files as a comment block, a plain block, or an application-specific application extension block. Several graphics editors use unofficial extension blocks the data used to generate the image, so it can be recovered further editing. All of these methods technically require the to broken into so that applications navigate the metadata without knowing its The Extensible Platform metadata unofficial but now widespread "XMP Data" extension for including XMP data in files. XMP data is encoded using UTF
 implement the Netscape AppliCation BlocK (NAB). THis BloCk, PlacEd imMediately beforE The sEquence of animation framEs, speCiFIes tHE nUmber Of times THe SEQueNcE oF frAmES sHould Be pLayed or That it shouLd rEpEat continuouSLy.  support for TheSe repeating aNimAtions FiRst APpearEd iN NetsCape NaVIgator Version 2.0, anD tHEn spreAD to otheR BRoWserS. Most browsers now rECoGNize and support nAB, thoUgH It IS Not StrIctly part oF tHe GIF89A SpecifiCAtION.

the FOllowing exampLe shows the sTRucTure of ThE anIMation File ROtATinG earth (large).Gif sHown (as a thUmbnaiL) At the toP Of the arTicle.

THe aNimAtioN DeLaY foR eACh fRAmE is SPecIfied in tHe gCe in huNdreDTHS Of a sEcoNd. SoMe ecoNomy of data is pOssIble WHerE a fraMe neeD onlY rEwritE a portIon of ThE pixels of the disPlay, Because thE ImAgE DeScRiptoR Can defIne A smAller reCtangle TO be ReSCANnEd instead of the wholE iMAGe. browsers Or otheR DiSpLAys that dO nOt sUppoRT AnimaTed Gifs TypicallY show oNLy ThE first fRaMe.

The sIzE anD coLor quALity Of animAted GIF fIles cAN vary significaNTly depending oN ThE APpLIcatIon Used to creatE theM. straTegiES fOr mINimizIng fiLe SIzE Include using a common GlObal coLor taBle for all framEs (rather thAN A Complete LocaL CoLOr table for each Frame) And minimizINg the numBer of Pixels coVered in suCCEssive frAmeS (so ThaT onLY ThE pixels that chANGe frOm One framE to The next Are IncLudEd iN tHe latter fRame). SimpLy PaCkInG a sEries OF indepenDeNt fRaMe iMages INto a coMposiTe anImAtIOn tEnds to yIElD LArge FiLe SizeS.

InTeRnet EXploREr sLows dowN GIFs if thE frAMe-raTe Is 20 Frames pEr second or higHeR and MicrosOfT rePorts tHAT Google CHrome and Safari also slow dOWn some GiF aNimatIons.

starting iN eaRly 1995, the uniVErsity Of Ulm uSed anImAteD giF as lIVE vIdeO sTreaming foRMAt tO show A cOntrOllable Model railroad.

MetadATa 
MEtadata can be sTorEd in gif fIleS As A ComMeNT blOCK, a plain text blocK, or an appliCaTIoN-specific aPPliCaTion extEnsion bLock.  SEVeral grAphics ediTors use unOfFiciAL AppLication exTension bLocks to inCLude tHE dAta usEd tO generAtE thE imagE, so thaT It cAn be rEcoverEd For furTher eDiTing.

All oF these methods technicallY requiRe the MetAdata to be BroKEn iNto sub-bloCks sO that appliCatIonS can nAviGAte thE metADaTa bLOck wiThouT Knowing itS InTerNAL sTructure.

The eXTEnsIble MEtaDAta PlaTforM (XMP) metadata standARd introduced an UnofFICiaL buT Now wIdEspread "XMP Data" AppLiCATion exteNsIon block for IncludinG Xmp data In GIF fIles. SiNce the Xmp DaTA is encOded UsiNg UTF
 implement the Netscape Ap plicationBlock  (N AB) .This  blo ck, placed imm e diat ely before the sequenc e ofan i mati o nframe s, spec i fi e s  th enu mbe ro ftimes  th e seque nce of fra mes  s hould be pla y ed  or that i t s hould repeat  co ntinuo us ly.  Supp ort  fortheser epeati ng animat io n s firs t  appear e d  i n Ne tscape Navigatorv er s ion 2.0, and t hen sp re a dt o  ot her  browsers.  M ost b r owsersn ow r e cog n ize and suppo rt NAB, tho u ghit isno t s t rictly  part  o f  th e GIF89a sp ecif ication.
The f o llowing example  shows  th e s truc t ur eofth e  an i ma tio n  fi le Rotat in gearth  (la r g e ) .gif  sh own(as a  thumbnail) a t t he t o p o f the  arti cle. 
The a nimati on de la y for each fram e is  specifie d i nthe  G CE in hundre dth s o f a sec ond. So m e e co n o m yof data is possibl ew h er e a fram e need on ly rewriteapor tion o f the  pix e ls  of thedispla y ,be cause t he  Image  D esc rip tor c a n de fine a  smaller  rect a ngle to be res c anned instead of t he whol e i mage. Brows erso r ot herd is pla y s tha t dono t  s u pport animated GIFs  t ypical ly sh ow only the f irst frame . The size  and co l or quality ofanima ted GIF fi l es can v ary s ignifica ntly depe n d ing on t heapp lic ati o n  u sed to create t hem.  S trategi esfor min imi zin g f ile  s ize inclu de using  a  c om mo n g lobal color ta bl e f or  al l fra m es (ra therthan  a  c o mpl ete loc a lc o lorta bl e fo r e ac h fra me)a ndminimiz ing the n umb e r of  p ix els cov ered in succe ss ive frames  ( sothat o n l y the pi xels that change from o n e frame  to  thenext  are incl ude d in t hel atterframe) . Sim pl y p a c kinga se rie sof indepen d e ntframe  i mage s intoa composite animat i ontends to yiel d l arge f il e s i ze s .
In t ern e t  Explorer slows  down GIFs  i f  t he frame-r a teis  20 fra mes per  seco n d or hi gher andMicrosoft  r epor t s  th at GoogleChrome a nd Safari alsos lo w dow n s ome GI Fani matio ns.

S t art ing i n earl y1995,the U ni versityof Ulm used animated GI F as l ive v ide o streami ngf orm at to sho w acontrollab lemod el ra ilr o ad.
Meta d at a M etada ta c a n be stor e dinG I Ffiles as ac o m men t blo ck, a plai n te xt block, or an a p plication-spec ific a ppl ica t ionex tension block.   S ev e r al graph ic s editors u se unoff ic i al ap plicat ion ex tension b lo c ks toincl ude  the data  us ed to gene ra te the im age,  s o that  it ca n  ber e covered for furt her e d i ting. 
Al l ofth ese met h odstechnicall y require t he met adat a tobe brok en  intosub -b locks so t h at applic ation s can n av igat e t he met adat a block  wit ho utknowing i t s  i n te rn a l s truc ture. 
TheExtensibl e  Metadat a P l atform(X MP) m etadat a  s t a ndard intr odu ced a n unofficial butn ow wides pread"XMP D ata" ap p lic at ion ext ens i o n block f or includ i ngXM P da ta in GI Ffile s.  Si nc e the XMP datais encod ed using U TF
 implement_the Netscape_Application Block (NAB). This_block, placed_immediately_before the_sequence_of animation frames,_specifies the number_of times the sequence_of frames should_be_played or that it should repeat continuously.  Support for these repeating animations first_appeared_in Netscape_Navigator_version_2.0, and then spread to_other browsers. Most browsers now_recognize and_support NAB, though it is not strictly part_of_the GIF89a specification.

The_following example shows the structure of the animation file_Rotating earth (large).gif shown (as a_thumbnail) at the_top_of_the article.

The animation delay_for each frame is specified in_the GCE in hundredths of a_second. Some economy of data is possible_where a frame need only rewrite_a portion of the pixels_of the_display, because the Image Descriptor_can define a_smaller rectangle_to be rescanned_instead of the whole image. Browsers_or other displays_that do not support animated GIFs_typically_show only the_first_frame.

The_size and_color quality of_animated_GIF files_can_vary significantly depending on the application_used_to create them. Strategies for minimizing file_size include using a_common_global color table for_all frames (rather than a_complete local color table for each_frame) and_minimizing the_number of pixels covered in successive frames (so that only the_pixels that change from one frame_to the next are_included in_the_latter frame). Simply_packing_a series_of independent frame images into a composite_animation tends_to yield large file sizes.

Internet Explorer_slows down GIFs if_the_frame-rate is 20 frames per second_or higher and Microsoft reports that_Google Chrome and Safari also_slow_down_some GIF animations.

Starting in early_1995, the University of Ulm used_animated GIF as_live video streaming format to show a_controllable_model railroad.

Metadata 
Metadata can be stored_in_GIF files as a comment block,_a_plain_text block, or an application-specific_application extension block.  Several graphics_editors use unofficial application extension blocks to include the_data used to_generate the image, so that_it_can_be recovered for further editing.

All of these methods technically require_the metadata_to be broken_into sub-blocks so that applications can navigate the metadata block_without knowing its internal structure.

The Extensible Metadata_Platform (XMP) metadata standard introduced an unofficial but now widespread "XMP_Data" application extension block for including XMP data_in GIF files. Since the XMP data_is encoded using UTF