HTMLImageElement.decoding - Web APIs
if doing so would cause problems, you can specify sync to disable asynchronous loading. ...
...if doing so would cause problems, you can specify sync to disable asynchronous loading. ...
...if doing so would cause problems, you can specify sync to disable asynchronous loading. ...
...And 6 more matches

MediaCapabilities.decodingInfo() - Web APIs
the mediacapabilities.decodinginfo() method, part of the media capabilities api, returns a promise with the tested media configuration's mediacapabilitiesinfo; this contains the three boolean properties supported, smooth, and powerefficient, which describe whether decoding the media described would be supported, smooth, and powerefficient. syntax mediacapabilities.decodinginfo(mediadecodingconfiguration) parameters mediadecodingconfiguration a valid mediadecodingconfiguration dictionary containing a valid media decoding type of file or media-source and a valid media configuration: either an audioconfiguration or a videoconfiguration. return value a promise fulfilling with a mediacapabilitiesinfo interface containing three boolean attributes: supported smooth powerefficient except...
...onfiguration dictionary containing a valid media decoding type of file or media-source and a valid media configuration: either an audioconfiguration or a videoconfiguration. return value a promise fulfilling with a mediacapabilitiesinfo interface containing three boolean attributes: supported smooth powerefficient exceptions a typeerror is raised if the mediaconfiguration passed to the decodinginfo() method is invalid, either because the type is not video or audio, the contenttype is not a valid codec mime type, the media decoding configuration is not a valid value for the media decoding type, or any other error in the media configuration passed to the method, including omitting values required in the media decoding configuration. example //create media configuration to be ...
...fig = { type : 'file', // or 'media-source' audio : { contenttype : "audio/ogg", // valid content type channels : 2, // audio channels used by the track bitrate : 132700, // number of bits used to encode 1s of audio samplerate : 5200 // number of audio samples making up that 1s. ...
...iacapabilities.decodinginfo(mediaconfig).then(result => { console.log('this configuration is ' + (result.supported ? '' : 'not ') + 'supported, ' + (result.smooth ? '' : 'not ') + 'smooth, and ' + (result.powerefficient ? '' : 'not ') + 'power efficient.') }); specifications specification status comment media capabilitiesthe definition of 'decodinginfo()' in that specification. draft initial definition ...

SVGImageElement.decoding - Web APIs
the decoding property of the svgimageelement interface represents a hint given to the browser on how it should decode the image. syntax var refstr = svgimageelement.decoding svgimageelement.decoding = refstr; values a domstring representing the decoding hint. possible values are: sync: decode the image synchronously for atomic presentation with other content. async: decode the image asynchronously to reduce delay in presenting other content. auto: default mode, which indicates no preference for the decoding mode. the browser decides what is best for the user. ...
... living standard initial definition. browser compatibility the compatibility table on this page is generated from structured data. ...
... living standard initial definition. browser compatibility the compatibility table on this page is generated from structured data. ...
...definition. browser compatibility the compatibility table on this page is generated from structured data. if you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. ...

MediaDecodingConfiguration - Web APIs
this takes one of two values: file: represents a configuration that is meant to be used for a plain file playback. media-source: represents a configuration that is meant to be used for playback of a mediasource. a media configuration — a videoconfiguration or audioconfiguration dictionary. ...
... 'media-source' video : { contenttype : "video/webm;codecs=vp8", // valid content type width : 800, // width of the video height : 600, // height of the video bitrate : 10000, // number of bits used to encode 1s of video framerate : 30 // number of frames making up that 1s. } }; // check support and performance navigator.mediacapabilities.decodinginfo(mediaconfig).then(result => { console.log('this configuration is ' + (result.supported ? '' : 'not ') + 'supported.') }); specifications specification status comment media capabilitiesthe definition of 'mediadecodingconfiguration' in that specification. draft initial definition ...

Index - Web APIs
iobuffersourcenode, media, method, reference, web audio api, sound, start undefined. 121 audioconfiguration api, audio, audioconfiguration, experimental, interface, media capabilities api, reference, video the audioconfiguration dictionary of the media capabilities api defines the audio file being tested when calling mediacapabilities.encodinginfo() or mediacapabilities.decodinginfo() to query whether a specific audio configuration is supported, smooth, and/or power efficient. 122 audiocontext api, audio, audiocontext, interface, reference, web audio api, sound the audiocontext interface represents an audio-processing graph built from audio modules linked together, each represented by an audionode. 123 audiocontext() audio, audio conte...
... api, htmlimageelement, image, property, reference, url, currentsrc, source the read-only htmlimageelement property currentsrc indicates the url of the image which is currently presented in the <img> element it represents. ...
...g> element it represents. 1719 htmlimageelement.decode() api, decode, graphics, html dom, htmlimageelement, images, loading, method, performance, reference, async, asynchronous, decoding the decode() method of the htmlimageelement interface returns a promise that resolves when the image is decoded and it is safe to append the image to the dom. 1720 htmlimageelement.decoding api, dom, htmlimageelement, property, reference, decoding the decoding property of the htmlimageelement interface represents a hint given to the browser on how it should decode the image. 1721 htmlimageelement.height api, html, html dom, htmlimageelement, image, property, reference, dimensions, height, size the height property of the htmlimageelement interface indic...
...And 16 more matches

Media Capabilities API - Web APIs
the media capabilities api allows developers to determine decoding and encoding abilities of the device, exposing information such as whether media is supported and whether playback should be smooth and power efficient, with real time feedback about playback to better enable adaptive streaming, and access to display property information. examples detect audio file support and expected performance this example defines a audio configuration then checks to see if the user agent supports decoding that media configuration, and whether it will perform well in terms of smoothness and power efficiency. if ('mediacapabilities' in navigator) { const audiofileconfiguration = { type : 'file', audio : { contenttype: "audio/mp3", channels: 2, bitrate: 132700, sam...
...see if the user agent supports decoding that media configuration, and whether it will perform well in terms of smoothness and power efficiency. ...
...different browsers support different media types and new media types are always being developed. ...
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Using the Media Capabilities API - Web APIs
s, the media capabilities api is available both on the main thread and from workers. if the object exists, media capabilities api is available. you can, therefore, test for the presence of the api like so: if ("mediacapabilities" in navigator) { // mediacapabilities is available } else { // mediacapabilities is not available } taking video as an example, to obtain information about video decoding abilities, you create a video decoding configuration which you pass as a parameter to mediacapabilities.decodinginfo() method. this returns a promise that fulfills with information about the media capabilities as to whether the video can be decoded, and whether decoding will be smooth and power efficient. you can also test audio decoding as well as video and audio encoding. creating a video dec...
...figuration which you pass as a parameter to mediacapabilities.decodinginfo() method. this returns a promise that fulfills with information about the media capabilities as to whether the video can be decoded, and whether decoding will be smooth and power efficient. you can also test audio decoding as well as video and audio encoding. creating a video decoding configuration the mediacapabilities.decodinginfo() method takes as a parameter a media decoding configuration. there are very specific ways to go about creating the configuration defined by the mediadecodingconfiguration dictionary. in our example, we are testing the decoding capabilities of a video configuration. the configuration requires the type of media being tested — e.g. a plain file or mediasource — and a videoconfiguration inc...
... } }; had we been testing encoding capabilities, we would have created a mediaencodingconfiguration, which requires the type of media being tested — either record (for recording media, i.e. a mediarecorder object) or transmission (for media transmitted over electronic means like rtcpeerconnection) — plus either an audio or video configuration as described above. querying the browser about decoding abilities now that we've created a video decoding configuration we can pass it as a paramater of the decodinginfo() method to determine if a video matching this configuration would be decodable and if the playback would be smooth and power efficient. var promise = navigator.mediacapabilities.decodinginfo(videoconfiguration); the decodinginfo() and encodinginfo() methods both return promises. o...
...And 5 more matches

Web video codec guide - Web media technologies
generally speaking, any configuration option that is intended to reduce the output size of the video will probably have a negative impact on the overall quality of the video, or will introduce certain types of artifacts into the video. it's also possible to select a lossless form of encoding, which will result in a much larger encoded file but with perfect reproduction of the original video upon decoding. in addition, each encoder utility may have variations in how they process the source video, resulting in differences in the output quality and/or size. video encoder configuration effects on quality and size feature effect on quality effect on size lossless compression no loss of quality lossless compression cannot reduce the overall video size nearly as much...
... most common ones you may see include: moiré patterns a unknown prefix: moiré pattern. is a large-scale spatial interference pattern produced when a pattern in the source image and the manner in which the encoder operates are slightly out of alignment spatially. the artifacts generated by the encoder then introduce strange, swirling effects in the source image's pattern upon decoding. staircase effect the staircase effect is a spatial artifact that occurs when diagonal straight or curved edges that should be smooth take on a jagged appearance, looking somewhat like a set of stair steps. this is the effect that is being reduced by "anti-aliasing" filters. wagon-wheel effect the wagon-wheel effect (or stroboscopic effect) is...
...les: main, high, and professional with increasing support for color depths and chroma subsampling. in addition, a series of levels are specified, each defining limits on a range of attributes of the video. ...
...And 4 more matches

StringView - Archive of obsolete content
] = 0x80 /* 128 */ + ((nchar >>> 6) & 0x3f /* 63 */); atarget[nidx++] = 0x80 /* 128 */ + (nchar & 0x3f /* 63 */); } return nidx; }; stringview.getutf8charlength = function (nchar) { return nchar < 0x80 ? 1 : nchar < 0x800 ? 2 : nchar < 0x10000 ? 3 : nchar < 0x200000 ? 4 : nchar < 0x4000000 ? 5 : 6; }; stringview.loadutf16charcode = function (achars, nidx) { /* utf-16 to domstring decoding algorithm */ var nfrstchr = achars[nidx]; return nfrstchr > 0xd7bf /* 55231 */ && nidx + 1 < achars.length ? (nfrstchr - 0xd800 /* 55296 */ << 10) + achars[nidx + 1] + 0x2400 /* 9216 */ : nfrstchr; }; stringview.pututf16charcode = function (atarget, nchar, nputat) { var nidx = nputat; if (nchar < 0x10000 /* 65536 */) { /* one element */ atarget[nidx++] = nchar; } el...
... if (nchar < 0x10000 /* 65536 */) { /* one element */ atarget[nidx++] = nchar; } else { /* two elements */ atarget[nidx++] = 0xd7c0 /* 55232 */ + (nchar >>> 10); atarget[nidx++] = 0xdc00 /* 56320 */ + (nchar & 0x3ff /* 1023 */); } return nidx; }; stringview.getutf16charlength = function (nchar) { return nchar < 0x10000 ? 1 : 2; }; /* array of bytes to base64 string decoding */ stringview.b64touint6 = function (nchr) { return nchr > 64 && nchr < 91 ? nchr - 65 : nchr > 96 && nchr < 123 ? nchr - 71 : nchr > 47 && nchr < 58 ? nchr + 4 : nchr === 43 ? 62 : nchr === 47 ? 63 : 0; }; stringview.uint6tob64 = function (nuint6) { return nuint6 < 26 ? nuint6 + 65 : nuint6 < 52 ? nuint6 + 71 : ...
... arguments base64string (required) a base64-encoded string which will be decoded and copied into the new stringview object. encoding optional a string expressing the encoding type. for possible values see here. byteoffset optional a number expressing the start offset in bytes of the new stringview. if not specified (or specified as null) it ...
...ts buffer. arguments wholebuffer optional a boolean expressing whether the returned base64-encoded string will correspond to the whole buffer (true) or to the stringview (false or omitted). examples var mystringview = new stringview("\u6432\u6432\u6432\u6432"); alert(stringview.makefrombase64(mystringview.tobase64())) // 搲搲搲搲 see also: base64 encoding and decoding. subview() syntax stringview.subview(characteroffset[, characterslength]) description returns a new stringview object which will share the same buffer. arguments characteroffset and characterslength will be treated as in string.prototype.substr(characteroffset[, characterslength) (see). if you want to create a new stringview object cloning without sharing the same buffer, loo...

Migrating from webkitAudioContext - Web APIs
odeaudiodata() method instead. ...
... file over the network, and then decoded it using createbuffer(): var xhr = new xmlhttprequest(); xhr.open("get", "/path/to/audio.ogg", true); xhr.responsetype = "arraybuffer"; xhr.send(); xhr.onload = function() { var decodedbuffer = context.createbuffer(xhr.response, false); if (decodedbuffer) { // decoding was successful, do something useful with the audio buffer } else { alert("decoding the audio buffer failed"); } }; converting this code to use decodeaudiodata() is relatively simple, as can be seen below: var xhr = new xmlhttprequest(); xhr.open("get", "/path/to/audio.ogg", true); xhr.responsetype = "arraybuffer"; xhr.send(); xhr.onload = function() { context.decodeaudiodata(xhr.response, function onsuccess(decodedbuffer) { // decoding was successful, do something us...
... this means that you may need to restructure your code to run the part which happened after the createb...
...uffer"; xhr.send(); xhr.onload = function() { context.decodeaudiodata(xhr.response, function onsuccess(decodedbuffer) { // decoding was successful, do something useful with the audio buffer }, function onfailure() { alert("decoding the audio buffer failed"); }); }; note that the decodeaudiodata() method is asynchronous, which means that it will return immediately, and then when the decoding finishes, one of the success or failure callback functions will get called depending on whether the audio decoding was successful. this means that you may need to restructure your code to run the part which happened after the createbuffer() call in the success callback, as you can see in the example above. renaming of audioparam.settargetvalueattime the settargetvalueattime() method on the aud...

Web audio codec guide - Web media technologies
processing of audio data to encode and decode it is handled by an audio codec (coder/decoder). in this article, we look at audio codecs used on the web to compress and decompress audio, what their capabilities and use cases are, and offer guidance when choosing audio codecs to use for your content. additionally, webrtc implementations generally use a subset of these codecs for their encoding and decoding of media, and may support additional codecs as well, for optimal cross-platform support of video and audio conferencing, and to integrate better with legacy telecommunication solutions. see codecs used by webrtc for details. for information about the fundamental concepts behind how digital audio works, see the article digital audio concepts. common codecs the list below denotes the codecs most...
...d audio size several factors affect the size of the encoded audio. some of these are a matter of the form of the source audio; others are related to decisions made while encoding the audio. lossless versus lossy codecs there are two basic categories of audio compression. lossless compression algorithms reduce the size of the audio without compromising the quality or fidelity of the sound. upon decoding audio compressed with a lossless codec such as flac or alac, the result is identical in every way to the original sound, down to the bit. lossy codecs, on the other hand, take advantage of the fact that the human ear is not a perfect interpreter of audio, and of the fact that the human brain can pluck the important information out of imperfect or noisy audio. they strip away audio frequencies th...
... advantage of the fact that the human ear is not a perfect interpreter of audio, and of the fact that the human brain can pluck the important information out of imperfect or noisy audio. they strip away audio frequencies that aren't used much, tolerate loss of precision in the decoded output, and use other methods to lose audio content, quality, and fidelity to produce smaller encoded media. upon decoding, the output is, to varying degrees, still understandable. the specific codec used—and the compression configuration selected—determine how close to the original, uncompressed audio signal the output seems to be when heard by the human ear. because of the differences in how lossy codecs work compared to lossless ones, especially the fact that lossless ones have to be much more conservative wi...
...ent of the app, such as games, you will need more control over the encoding process and more options surrounding the format used while encoding the audio. a few popular options: ffmpeg arguably the best-known and most widely regarded open source codec packages available, ffmpeg supports the majority of the most popular audio formats and provides command-line tools and libraries for encoding, decoding, and performing format conversions of both audio and video. binaries are available for macos, linux, and windows. handbrake a highly popular open source front-end to ffmpeg which adds a graphical user interface that makes it much easier to control the wide variety of options ffmpeg offers while encoding audio and/or video. binaries are available for macos, linux, and windows. audacity an open...

Index
ctions once a handle is no longer needed. this is particularly important for applications that might need to close a database and reinitialize nss using a different one, without restarting. such an operation might fail at runtime if data elements are still being referenced. in addition to the freebl, softoken, and ckbi modules, there is an utility library for general operations (e.g., encoding/decoding between data formats, a list of standardized object identifiers (oid)). nss has an ssl/tls module that implements the secure sockets layer/transport layer security network protocols, an s/mime module that implements cms messaging used by secure email and some instant messaging implementations, a dbm library that implements the classic database storage, and finally a core nss library for the big s...
... -f turn on fancy printing. output is printed in colored html. data sent from the client to the server is in blue; the server's reply is in red. when used with looping mode, the different connections are separated with horizontal lines. you can use this option to upload the output into a browser. -s turn on ssl parsing and decoding. the tool does not automatically detect ssl sessions. if you are intercepting an ssl connection, use this option so that the tool can detect and decode ssl structures. if the tool detects a certificate chain, it saves the der-encoded certificates into files in the current directory. the files are named cert.0x, where x is the sequ...
...encrypted > } ] >-- [ sslrecord { type = 23 (application_data) version = { 3,0 } length = 223 (0xdf) > encrypted > } sslrecord { type = 21 (alert) version = { 3,0 } length = 18 (0x12) > encrypted > } ] server socket closed. example 3 in this example, the -h option turns hex/ascii format. there is no ssl parsing or decoding. the output is routed to a text file. $ ssltap -h -p 444 interzone.mcom.com:443 > h.txt output connected to interzone.mcom.com:443 --> [ 0: 80 40 01 03 00 00 27 00 00 00 10 01 00 80 02 00 | .@....'......... 10: 80 03 00 80 04 00 80 06 00 40 07 00 c0 00 00 04 | .........@...... 20: 00 ff e0 00 00 0a 00 ff e1 00 00 09 00 00 03 00 | ........á....... 30: 00 06 9...

nss tech note1
hod type, this may be a bug). sec_asn1_dynamic or sec_asn1_xtrn : specifies that the component format is defined in a dynamic subtemplate. there is no difference between the two macros. the sub field of the template points to a callback function of type sec_asn1templatechooser that returns the subtemplate depending on the component data. ...
...cros. the sub field of the template points to a callback function of type sec_asn1templatechooser that returns the subtemplate depending on the component data. sec_asn1_skip: specifies that the decoder should skip decoding of the component. sec_asn1decodeitem can only skip required components and will assert if you try to skip an optional component. sec_quickderdecodeitem supports skipping the decoding of optional components if you define the tag of the component in the template sec_asn1_inner: recurse into the component and saves its content, without the surrounding asn.1 tag and length sec_asn1_save: saves the component data, but does not proceed to the next component if within a sequence template array. this means the next template will reprocess the same component. sec_asn1_skip_re...
...omponents if you define the tag of the component in the template sec_asn1_inner: recurse into the component and saves its content, without the surrounding asn.1 tag and length sec_asn1_save: saves the component data, but does not proceed to the next component if within a sequence template array. this means the next template will reprocess the same component. sec_asn1_skip_rest: abort the decoding. this is used in a template array within a sequence, if you don't care about the fields at the end of it. sec_asn1decodeitem only supports this modifier in the top-level template. sec_quickderdecodeitem allows it at any nested sublevel. sec_asn1_choice: allows decoding of components that are of variable type. this must be the first template in a null-terminated array. the offset parameter spec...

Digital audio concepts - Web media technologies
les per second), this means each second of audio occupies 192 kb of memory. therefore, a typical three-minute song requires about 34.5 mb of memory. that's a lot of storage, but worse, it's an insane amount of network bandwidth to use for a relatively short piece of audio. that's why most digital audio is compressed. the process of compressing and decompressing audio is performed by encoding and decoding it using an audio codec (coder/decoder). over the years, a large variety of codecs have been developed, several of which are commonly used on the web. for details about the most important and useful ones for web developers to be familiar with, see the article guide to audio codecs used on the web. audio channels and frames there are two types of audio channel. standard audio channels are used t...
...choacoustics may use any of the techniques mentioned here, and will almost certainly apply others as well. all of this means there is a fundamental question that has to be asked and answered before choosing a codec: given the content of the sound, the usage context, and the target audience, is it acceptable to lose some degree of audio fidelity, and if so, how much; or is it necessary that, upon decoding the data, the result be identical to the source audio? lossy vs lossless compression if loss of detail and potentially fidelity is unacceptable or undesirable, a lossless codec is preferred. on the other hand, if some degree of reduction of audio fidelity is okay, a lossy codec can be used. generally, lossy compression results in significantly smaller output than lossless compression methods; a...
... then you store the values of mid and side. while mid is still the same size as your sample size (such as 16 bits), the value of side can probably be stored in a smaller number of bits, since the amplitude of the two channels is probably relatively similar. the encoder can then take this smaller number of total bits per frame and perform additional computations to further reduce the size. while decoding the audio, the absolute left and right channel values are calculated like this: l=mid + sidel\quad =\quad mid\quad +\quad side r=mid - sidel\quad =\quad mid\quad -\quad side on its own, mid-side stereo coding is lossless, and is commonly used by both lossless and lossy audio codecs. any loss of detail comes from other steps of the encoding process. intensity stereo coding intensity stereo ...

Graceful asynchronous programming with Promises - Learn web development
n this case the .all() block will always get fulfilled. if you wanted the .all() to reject, you'd have to chain the .catch() block on to the end of the .all() instead. the code inside the function body is async and promise-based, therefore in effect, the entire function acts like a promise — convenient. next, we call our function three times to begin the process of fetching and decoding the images and text and store each of the returned promises in a variable. add the following below your previous code: let coffee = fetchanddecode('coffee.jpg', 'blob'); let tea = fetchanddecode('tea.jpg', 'blob'); let description = fetchanddecode('description.txt', 'text'); next, we will define a promise.all() block to run some code only when all three of the promises stored above have ...
...ly attractive way! the code we provided here for displaying the items is fairly rudimentary but works as an explainer for now. note: if you get stuck, you can compare your version of the code to ours, to see what it is meant to look like — see it live, and see the source code. note: if you were improving this code, you might want to loop through a list of items to display, fetching and decoding each one, and then loop through the results inside promise.all(), running a different function to display each one depending on what the type of code was. this would make it work for any number of items, not just three. also, you could determine what the type of file is being fetched without needing an explicit type property. you could, for example, check the content-type http header of the resp...