1624956517
Resize images in browser without pixelation and reasonably fast. Autoselect the best of available technologies: webworkers, webassembly, createImageBitmap, pure JS.
With pica you can:
Note. If you need File/Blob resize (from form’s file input), consider use image-blob-reduce. It has additional machinery to process orientation, keep EXIF metadata and so on.
Multiply unsharpAmount
by 2, divide unsharpThreshold
by 2, example:
pica@6
: pica.resize(a, b, { unsharpAmount: 80, unsharpThreshold: 2 })
pica@7
: pica.resize(a, b, { unsharpAmount: 160, unsharpThreshold: 1 })
Here is a short list of problems you can face:
Access-Control-Allow-Origin
header.canvas.toBlob()
method. Use pica.toBlob()
, it includes required shim.exif
data. Consider use image-blob-reduce.npm install pica
const pica = require('pica')();
// Resize from Canvas/Image to another Canvas
pica.resize(from, to, {
unsharpAmount: 160,
unsharpRadius: 0.6,
unsharpThreshold: 1
})
.then(result => console.log('resize done!'));
// Resize & convert to blob
pica.resize(from, to)
.then(result => pica.toBlob(result, 'image/jpeg', 0.90))
.then(blob => console.log('resized to canvas & created blob!'));
Create resizer instance with given config (optional):
[ 'js', 'wasm', 'ww' ]
. Can be [ 'js', 'wasm', 'cib', 'ww' ]
or [ 'all' ]
.Important! Latest browsers may support resize via createImageBitmap. This feature is supported (cib
) but disabled by default and not recommended for use. So:
createImageBitmap()
is used for non-blocking image decode (when available, without downscale).cib
will depend on your browser. Result without cib
will be predictable and good.Resize image from one canvas (or image) to another. Sizes are taken from source and destination objects.
Canvas
, Image
or ImageBitmap
.3
(lanczos, win=3).false
.0
(off). Usually between 100 to 200 is good.0
. Threshold for applying unsharp mask.Result is Promise, resolved with to
on success.
(!) If you need to process multiple images, do it sequentially to optimize CPU & memory use. Pica already knows how to use multiple cores (if browser allows).
Convenience method, similar to canvas.toBlob()
, but with promise interface & polyfill for old browsers.
Supplementary method, not recommended for direct use. Resize Uint8Array with raw RGBA bitmap (don’t confuse with jpeg / png / … binaries). It does not use tiles & webworkers. Left for special cases when you really need to process raw binary data (for example, if you decode jpeg files “manually”).
3
(lanczos, win=3).false
.0
(off). Usually between 50 to 100 is good.0
. Threshold for applying unsharp mask.pica
to create new one.Result is Promise, resolved with resized rgba buffer.
Pica has presets to adjust speed/quality ratio. Simply use quality
option param:
In real world you will never need to change default (max) quality. All this variations were implemented to better understand resize math :)
After scale down image can look a bit blured. It’s good idea to sharpen it a bit. Pica has built-in “unsharp mask” filter (off by default). Set unsharpAmount
to positive number to activate the filter.
Filter’s parameters are similar to ones from Photoshop. We recommend to start with unsharpAmount = 160
, unsharpRadius = 0.6
and unsharpThreshold = 1
. There is a correspondence between UnsharpMask parameters in popular graphics software.
We didn’t have time to test all possible combinations, but in general:
Note. Though you can run this package on node.js
, browsers are the main target platform. On server side we recommend to use sharp.
You can find these links useful:
Available as part of the Tidelift Subscription.
The maintainers of pica and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source packages you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact packages you use. Learn more.
Author: nodeca
The Demo/Documentation: View The Demo/Documentation
Download Link: Download The Source Code
Official Website: https://github.com/nodeca/pica
License: MIT
#image #pica #web-development #webdev
1653123600
This repository is a fork of SimpleMDE, made by Sparksuite. Go to the dedicated section for more information.
A drop-in JavaScript text area replacement for writing beautiful and understandable Markdown. EasyMDE allows users who may be less experienced with Markdown to use familiar toolbar buttons and shortcuts.
In addition, the syntax is rendered while editing to clearly show the expected result. Headings are larger, emphasized words are italicized, links are underlined, etc.
EasyMDE also features both built-in auto saving and spell checking. The editor is entirely customizable, from theming to toolbar buttons and javascript hooks.
Via npm:
npm install easymde
Via the UNPKG CDN:
<link rel="stylesheet" href="https://unpkg.com/easymde/dist/easymde.min.css">
<script src="https://unpkg.com/easymde/dist/easymde.min.js"></script>
Or jsDelivr:
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/easymde/dist/easymde.min.css">
<script src="https://cdn.jsdelivr.net/npm/easymde/dist/easymde.min.js"></script>
After installing and/or importing the module, you can load EasyMDE onto the first textarea
element on the web page:
<textarea></textarea>
<script>
const easyMDE = new EasyMDE();
</script>
Alternatively you can select a specific textarea
, via JavaScript:
<textarea id="my-text-area"></textarea>
<script>
const easyMDE = new EasyMDE({element: document.getElementById('my-text-area')});
</script>
Use easyMDE.value()
to get the content of the editor:
<script>
easyMDE.value();
</script>
Use easyMDE.value(val)
to set the content of the editor:
<script>
easyMDE.value('New input for **EasyMDE**');
</script>
true
, force downloads Font Awesome (used for icons). If set to false
, prevents downloading. Defaults to undefined
, which will intelligently check whether Font Awesome has already been included, then download accordingly.true
, focuses the editor automatically. Defaults to false
.true
, saves the text automatically. Defaults to false
.10000
(10 seconds).autosave.delay
or 10000
(10 seconds).locale: en-US, format: hour:minute
.{ delay: 300 }
, it will check every 300 ms if the editor is visible and if positive, call CodeMirror's refresh()
.**
or __
. Defaults to **
.```
or ~~~
. Defaults to ```
.*
or _
. Defaults to *
.*
, -
or +
. Defaults to *
.textarea
element to use. Defaults to the first textarea
element on the page.true
, force text changes made in EasyMDE to be immediately stored in original text area. Defaults to false
.false
, indent using spaces instead of tabs. Defaults to true
.false
by default, preview for images will appear only for images on separate lines.
as argument and returns a string that serves as the src
attribute of the <img>
tag in the preview. Enables dynamic previewing of images in the frontend without having to upload them to a server, allows copy-pasting of images to the editor with preview.["[", "](http://)"]
.true
, enables line numbers in the editor.false
, disable line wrapping. Defaults to true
."500px"
. Defaults to "300px"
.minHeight
option will be ignored. Should be a string containing a valid CSS value like "500px"
. Defaults to undefined
.true
when the editor is currently going into full screen mode, or false
.true
, will render headers without a space after the #
. Defaults to false
.false
, will not process GFM strikethrough syntax. Defaults to true
.true
, let underscores be a delimiter for separating words. Defaults to false
.false
, will replace CSS classes returned by the default Markdown mode. Otherwise the classes returned by the custom mode will be combined with the classes returned by the default mode. Defaults to true
."editor-preview"
.true
, a JS alert window appears asking for the link or image URL. Defaults to false
.URL of the image:
.URL for the link:
.true
, enables the image upload functionality, which can be triggered by drag and drop, copy-paste and through the browse-file window (opened when the user click on the upload-image icon). Defaults to false
.1024 * 1024 * 2
(2 MB).image/png, image/jpeg
.imageMaxSize
, imageAccept
, imageUploadEndpoint
and imageCSRFToken
ineffective.onSuccess
and onError
callback functions as parameters. onSuccess(imageUrl: string)
and onError(errorMessage: string)
{"data": {"filePath": "<filePath>"}}
where filePath is the path of the image (absolute if imagePathAbsolute
is set to true, relative if otherwise);{"error": "<errorCode>"}
, where errorCode can be noFileGiven
(HTTP 400 Bad Request), typeNotAllowed
(HTTP 415 Unsupported Media Type), fileTooLarge
(HTTP 413 Payload Too Large) or importError
(see errorMessages below). If errorCode is not one of the errorMessages, it is alerted unchanged to the user. This allows for server-side error messages. No default value.true
, will treat imageUrl
from imageUploadFunction
and filePath returned from imageUploadEndpoint
as an absolute rather than relative path, i.e. not prepend window.location.origin
to it.imageCSRFToken
has value, defaults to csrfmiddlewaretoken
.true
, passing CSRF token via header. Defaults to false
, which pass CSRF through request body.#image_name#
, #image_size#
and #image_max_size#
will replaced by their respective values, that can be used for customization or internationalization:uploadImage
is set to true
. Defaults to Attach files by drag and dropping or pasting from clipboard.
.Drop image to upload it.
.Uploading images #images_names#
.Uploading #file_name#: #progress#%
.Uploaded #image_name#
.B, KB, MB
(example: 218 KB
). You can use B,KB,MB
instead if you prefer without whitespaces (218KB
).errorCallback
option, where #image_name#
, #image_size#
and #image_max_size#
will replaced by their respective values, that can be used for customization or internationalization:You must select a file.
.imageAccept
list, or the server returned this error code. Defaults to This image type is not allowed.
.imageMaxSize
, or if the server returned this error code. Defaults to Image #image_name# is too big (#image_size#).\nMaximum file size is #image_max_size#.
.Something went wrong when uploading the image #image_name#.
.(errorMessage) => alert(errorMessage)
.true
, will highlight using highlight.js. Defaults to false
. To use this feature you must include highlight.js on your page or pass in using the hljs
option. For example, include the script and the CSS files like:<script src="https://cdn.jsdelivr.net/highlight.js/latest/highlight.min.js"></script>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/highlight.js/latest/styles/github.min.css">
window.hljs
), you can provide an instance here. Defaults to undefined
.renderingConfig
options will take precedence.false
, disable parsing GitHub Flavored Markdown (GFM) single line breaks. Defaults to true
.false
, disable the spell checker. Defaults to true
. Optionally pass a CodeMirrorSpellChecker-compliant function.textarea
or contenteditable
. Defaults to textarea
for desktop and contenteditable
for mobile. contenteditable
option is necessary to enable nativeSpellcheck.false
, disable native spell checker. Defaults to true
.false
, allows side-by-side editing without going into fullscreen. Defaults to true
.false
, hide the status bar. Defaults to the array of built-in status bar items.false
, remove the CodeMirror-selectedtext
class from selected lines. Defaults to true
.false
, disable syncing scroll in side by side mode. Defaults to true
.2
.easymde
.false
, hide the toolbar. Defaults to the array of icons.false
, disable toolbar button tips. Defaults to true
.rtl
or ltr
. Changes text direction to support right-to-left languages. Defaults to ltr
.Most options demonstrate the non-default behavior:
const editor = new EasyMDE({
autofocus: true,
autosave: {
enabled: true,
uniqueId: "MyUniqueID",
delay: 1000,
submit_delay: 5000,
timeFormat: {
locale: 'en-US',
format: {
year: 'numeric',
month: 'long',
day: '2-digit',
hour: '2-digit',
minute: '2-digit',
},
},
text: "Autosaved: "
},
blockStyles: {
bold: "__",
italic: "_",
},
unorderedListStyle: "-",
element: document.getElementById("MyID"),
forceSync: true,
hideIcons: ["guide", "heading"],
indentWithTabs: false,
initialValue: "Hello world!",
insertTexts: {
horizontalRule: ["", "\n\n-----\n\n"],
image: [""],
link: ["[", "](https://)"],
table: ["", "\n\n| Column 1 | Column 2 | Column 3 |\n| -------- | -------- | -------- |\n| Text | Text | Text |\n\n"],
},
lineWrapping: false,
minHeight: "500px",
parsingConfig: {
allowAtxHeaderWithoutSpace: true,
strikethrough: false,
underscoresBreakWords: true,
},
placeholder: "Type here...",
previewClass: "my-custom-styling",
previewClass: ["my-custom-styling", "more-custom-styling"],
previewRender: (plainText) => customMarkdownParser(plainText), // Returns HTML from a custom parser
previewRender: (plainText, preview) => { // Async method
setTimeout(() => {
preview.innerHTML = customMarkdownParser(plainText);
}, 250);
return "Loading...";
},
promptURLs: true,
promptTexts: {
image: "Custom prompt for URL:",
link: "Custom prompt for URL:",
},
renderingConfig: {
singleLineBreaks: false,
codeSyntaxHighlighting: true,
sanitizerFunction: (renderedHTML) => {
// Using DOMPurify and only allowing <b> tags
return DOMPurify.sanitize(renderedHTML, {ALLOWED_TAGS: ['b']})
},
},
shortcuts: {
drawTable: "Cmd-Alt-T"
},
showIcons: ["code", "table"],
spellChecker: false,
status: false,
status: ["autosave", "lines", "words", "cursor"], // Optional usage
status: ["autosave", "lines", "words", "cursor", {
className: "keystrokes",
defaultValue: (el) => {
el.setAttribute('data-keystrokes', 0);
},
onUpdate: (el) => {
const keystrokes = Number(el.getAttribute('data-keystrokes')) + 1;
el.innerHTML = `${keystrokes} Keystrokes`;
el.setAttribute('data-keystrokes', keystrokes);
},
}], // Another optional usage, with a custom status bar item that counts keystrokes
styleSelectedText: false,
sideBySideFullscreen: false,
syncSideBySidePreviewScroll: false,
tabSize: 4,
toolbar: false,
toolbarTips: false,
});
Below are the built-in toolbar icons (only some of which are enabled by default), which can be reorganized however you like. "Name" is the name of the icon, referenced in the JavaScript. "Action" is either a function or a URL to open. "Class" is the class given to the icon. "Tooltip" is the small tooltip that appears via the title=""
attribute. Note that shortcut hints are added automatically and reflect the specified action if it has a key bind assigned to it (i.e. with the value of action
set to bold
and that of tooltip
set to Bold
, the final text the user will see would be "Bold (Ctrl-B)").
Additionally, you can add a separator between any icons by adding "|"
to the toolbar array.
Name | Action | Tooltip Class |
---|---|---|
bold | toggleBold | Bold fa fa-bold |
italic | toggleItalic | Italic fa fa-italic |
strikethrough | toggleStrikethrough | Strikethrough fa fa-strikethrough |
heading | toggleHeadingSmaller | Heading fa fa-header |
heading-smaller | toggleHeadingSmaller | Smaller Heading fa fa-header |
heading-bigger | toggleHeadingBigger | Bigger Heading fa fa-lg fa-header |
heading-1 | toggleHeading1 | Big Heading fa fa-header header-1 |
heading-2 | toggleHeading2 | Medium Heading fa fa-header header-2 |
heading-3 | toggleHeading3 | Small Heading fa fa-header header-3 |
code | toggleCodeBlock | Code fa fa-code |
quote | toggleBlockquote | Quote fa fa-quote-left |
unordered-list | toggleUnorderedList | Generic List fa fa-list-ul |
ordered-list | toggleOrderedList | Numbered List fa fa-list-ol |
clean-block | cleanBlock | Clean block fa fa-eraser |
link | drawLink | Create Link fa fa-link |
image | drawImage | Insert Image fa fa-picture-o |
table | drawTable | Insert Table fa fa-table |
horizontal-rule | drawHorizontalRule | Insert Horizontal Line fa fa-minus |
preview | togglePreview | Toggle Preview fa fa-eye no-disable |
side-by-side | toggleSideBySide | Toggle Side by Side fa fa-columns no-disable no-mobile |
fullscreen | toggleFullScreen | Toggle Fullscreen fa fa-arrows-alt no-disable no-mobile |
guide | This link | Markdown Guide fa fa-question-circle |
undo | undo | Undo fa fa-undo |
redo | redo | Redo fa fa-redo |
Customize the toolbar using the toolbar
option.
Only the order of existing buttons:
const easyMDE = new EasyMDE({
toolbar: ["bold", "italic", "heading", "|", "quote"]
});
All information and/or add your own icons
const easyMDE = new EasyMDE({
toolbar: [
{
name: "bold",
action: EasyMDE.toggleBold,
className: "fa fa-bold",
title: "Bold",
},
"italics", // shortcut to pre-made button
{
name: "custom",
action: (editor) => {
// Add your own code
},
className: "fa fa-star",
title: "Custom Button",
attributes: { // for custom attributes
id: "custom-id",
"data-value": "custom value" // HTML5 data-* attributes need to be enclosed in quotation marks ("") because of the dash (-) in its name.
}
},
"|" // Separator
// [, ...]
]
});
Put some buttons on dropdown menu
const easyMDE = new EasyMDE({
toolbar: [{
name: "heading",
action: EasyMDE.toggleHeadingSmaller,
className: "fa fa-header",
title: "Headers",
},
"|",
{
name: "others",
className: "fa fa-blind",
title: "others buttons",
children: [
{
name: "image",
action: EasyMDE.drawImage,
className: "fa fa-picture-o",
title: "Image",
},
{
name: "quote",
action: EasyMDE.toggleBlockquote,
className: "fa fa-percent",
title: "Quote",
},
{
name: "link",
action: EasyMDE.drawLink,
className: "fa fa-link",
title: "Link",
}
]
},
// [, ...]
]
});
EasyMDE comes with an array of predefined keyboard shortcuts, but they can be altered with a configuration option. The list of default ones is as follows:
Shortcut (Windows / Linux) | Shortcut (macOS) | Action |
---|---|---|
Ctrl-' | Cmd-' | "toggleBlockquote" |
Ctrl-B | Cmd-B | "toggleBold" |
Ctrl-E | Cmd-E | "cleanBlock" |
Ctrl-H | Cmd-H | "toggleHeadingSmaller" |
Ctrl-I | Cmd-I | "toggleItalic" |
Ctrl-K | Cmd-K | "drawLink" |
Ctrl-L | Cmd-L | "toggleUnorderedList" |
Ctrl-P | Cmd-P | "togglePreview" |
Ctrl-Alt-C | Cmd-Alt-C | "toggleCodeBlock" |
Ctrl-Alt-I | Cmd-Alt-I | "drawImage" |
Ctrl-Alt-L | Cmd-Alt-L | "toggleOrderedList" |
Shift-Ctrl-H | Shift-Cmd-H | "toggleHeadingBigger" |
F9 | F9 | "toggleSideBySide" |
F11 | F11 | "toggleFullScreen" |
Here is how you can change a few, while leaving others untouched:
const editor = new EasyMDE({
shortcuts: {
"toggleOrderedList": "Ctrl-Alt-K", // alter the shortcut for toggleOrderedList
"toggleCodeBlock": null, // unbind Ctrl-Alt-C
"drawTable": "Cmd-Alt-T", // bind Cmd-Alt-T to drawTable action, which doesn't come with a default shortcut
}
});
Shortcuts are automatically converted between platforms. If you define a shortcut as "Cmd-B", on PC that shortcut will be changed to "Ctrl-B". Conversely, a shortcut defined as "Ctrl-B" will become "Cmd-B" for Mac users.
The list of actions that can be bound is the same as the list of built-in actions available for toolbar buttons.
You can catch the following list of events: https://codemirror.net/doc/manual.html#events
const easyMDE = new EasyMDE();
easyMDE.codemirror.on("change", () => {
console.log(easyMDE.value());
});
You can revert to the initial text area by calling the toTextArea
method. Note that this clears up the autosave (if enabled) associated with it. The text area will retain any text from the destroyed EasyMDE instance.
const easyMDE = new EasyMDE();
// ...
easyMDE.toTextArea();
easyMDE = null;
If you need to remove registered event listeners (when the editor is not needed anymore), call easyMDE.cleanup()
.
The following self-explanatory methods may be of use while developing with EasyMDE.
const easyMDE = new EasyMDE();
easyMDE.isPreviewActive(); // returns boolean
easyMDE.isSideBySideActive(); // returns boolean
easyMDE.isFullscreenActive(); // returns boolean
easyMDE.clearAutosavedValue(); // no returned value
EasyMDE is a continuation of SimpleMDE.
SimpleMDE began as an improvement of lepture's Editor project, but has now taken on an identity of its own. It is bundled with CodeMirror and depends on Font Awesome.
CodeMirror is the backbone of the project and parses much of the Markdown syntax as it's being written. This allows us to add styles to the Markdown that's being written. Additionally, a toolbar and status bar have been added to the top and bottom, respectively. Previews are rendered by Marked using GitHub Flavored Markdown (GFM).
I originally made this fork to implement FontAwesome 5 compatibility into SimpleMDE. When that was done I submitted a pull request, which has not been accepted yet. This, and the project being inactive since May 2017, triggered me to make more changes and try to put new life into the project.
Changes include:
https://
by defaultMy intention is to continue development on this project, improving it and keeping it alive.
You may want to edit this library to adapt its behavior to your needs. This can be done in some quick steps:
gulp
command, which will generate files: dist/easymde.min.css
and dist/easymde.min.js
;Want to contribute to EasyMDE? Thank you! We have a contribution guide just for you!
Author: Ionaru
Source Code: https://github.com/Ionaru/easy-markdown-editor
License: MIT license
1624956517
Resize images in browser without pixelation and reasonably fast. Autoselect the best of available technologies: webworkers, webassembly, createImageBitmap, pure JS.
With pica you can:
Note. If you need File/Blob resize (from form’s file input), consider use image-blob-reduce. It has additional machinery to process orientation, keep EXIF metadata and so on.
Multiply unsharpAmount
by 2, divide unsharpThreshold
by 2, example:
pica@6
: pica.resize(a, b, { unsharpAmount: 80, unsharpThreshold: 2 })
pica@7
: pica.resize(a, b, { unsharpAmount: 160, unsharpThreshold: 1 })
Here is a short list of problems you can face:
Access-Control-Allow-Origin
header.canvas.toBlob()
method. Use pica.toBlob()
, it includes required shim.exif
data. Consider use image-blob-reduce.npm install pica
const pica = require('pica')();
// Resize from Canvas/Image to another Canvas
pica.resize(from, to, {
unsharpAmount: 160,
unsharpRadius: 0.6,
unsharpThreshold: 1
})
.then(result => console.log('resize done!'));
// Resize & convert to blob
pica.resize(from, to)
.then(result => pica.toBlob(result, 'image/jpeg', 0.90))
.then(blob => console.log('resized to canvas & created blob!'));
Create resizer instance with given config (optional):
[ 'js', 'wasm', 'ww' ]
. Can be [ 'js', 'wasm', 'cib', 'ww' ]
or [ 'all' ]
.Important! Latest browsers may support resize via createImageBitmap. This feature is supported (cib
) but disabled by default and not recommended for use. So:
createImageBitmap()
is used for non-blocking image decode (when available, without downscale).cib
will depend on your browser. Result without cib
will be predictable and good.Resize image from one canvas (or image) to another. Sizes are taken from source and destination objects.
Canvas
, Image
or ImageBitmap
.3
(lanczos, win=3).false
.0
(off). Usually between 100 to 200 is good.0
. Threshold for applying unsharp mask.Result is Promise, resolved with to
on success.
(!) If you need to process multiple images, do it sequentially to optimize CPU & memory use. Pica already knows how to use multiple cores (if browser allows).
Convenience method, similar to canvas.toBlob()
, but with promise interface & polyfill for old browsers.
Supplementary method, not recommended for direct use. Resize Uint8Array with raw RGBA bitmap (don’t confuse with jpeg / png / … binaries). It does not use tiles & webworkers. Left for special cases when you really need to process raw binary data (for example, if you decode jpeg files “manually”).
3
(lanczos, win=3).false
.0
(off). Usually between 50 to 100 is good.0
. Threshold for applying unsharp mask.pica
to create new one.Result is Promise, resolved with resized rgba buffer.
Pica has presets to adjust speed/quality ratio. Simply use quality
option param:
In real world you will never need to change default (max) quality. All this variations were implemented to better understand resize math :)
After scale down image can look a bit blured. It’s good idea to sharpen it a bit. Pica has built-in “unsharp mask” filter (off by default). Set unsharpAmount
to positive number to activate the filter.
Filter’s parameters are similar to ones from Photoshop. We recommend to start with unsharpAmount = 160
, unsharpRadius = 0.6
and unsharpThreshold = 1
. There is a correspondence between UnsharpMask parameters in popular graphics software.
We didn’t have time to test all possible combinations, but in general:
Note. Though you can run this package on node.js
, browsers are the main target platform. On server side we recommend to use sharp.
You can find these links useful:
Available as part of the Tidelift Subscription.
The maintainers of pica and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source packages you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact packages you use. Learn more.
Author: nodeca
The Demo/Documentation: View The Demo/Documentation
Download Link: Download The Source Code
Official Website: https://github.com/nodeca/pica
License: MIT
#image #pica #web-development #webdev
1644628080
pica - high quality image resize in browser
Resize images in browser without pixelation and reasonably fast. Autoselect the best of available technologies: webworkers, webassembly, createImageBitmap, pure JS.
With pica you can:
Note. If you need File/Blob resize (from form's file input), consider use image-blob-reduce. It has additional machinery to process orientation, keep EXIF metadata and so on.
Multiply unsharpAmount
by 2, divide unsharpThreshold
by 2, example:
pica@6
: pica.resize(a, b, { unsharpAmount: 80, unsharpThreshold: 2 })
pica@7
: pica.resize(a, b, { unsharpAmount: 160, unsharpThreshold: 1 })
Here is a short list of problems you can face:
Access-Control-Allow-Origin
header.canvas.toBlob()
method. Use pica.toBlob()
, it includes required shim.exif
data. Consider use image-blob-reduce.npm install pica
const pica = require('pica')();
// Resize from Canvas/Image to another Canvas
pica.resize(from, to)
.then(result => console.log('resize done!'));
// Resize & convert to blob
pica.resize(from, to)
.then(result => pica.toBlob(result, 'image/jpeg', 0.90))
.then(blob => console.log('resized to canvas & created blob!'));
Create resizer instance with given config (optional):
[ 'js', 'wasm', 'ww' ]
. Can be [ 'js', 'wasm', 'cib', 'ww' ]
or [ 'all' ]
. Note, cib
is buggy in Chrome and not supports default mks2013
filter.Important! Latest browsers may support resize via createImageBitmap. This feature is supported (cib
) but disabled by default and not recommended for use. So:
createImageBitmap()
is used for non-blocking image decode (when available, without downscale).cib
will depend on your browser. Result without cib
will be predictable and good.Resize image from one canvas (or image) to another. Sizes are taken from source and destination objects.
Canvas
, Image
or ImageBitmap
..filter
instead) - 0..3.mks2013
). See resize_filter_info.js for details. mks2013
does both resize and sharpening, it's optimal and not recommended to change.0
(off). Usually value between 100 to 200 is good. Note, mks2013
filter already does optimal sharpening.0
. Threshold for applying unsharp mask.Result is Promise, resolved with to
on success.
(!) If you need to process multiple images, do it sequentially to optimize CPU & memory use. Pica already knows how to use multiple cores (if browser allows).
Convenience method, similar to canvas.toBlob()
, but with promise interface & polyfill for old browsers.
Supplementary method, not recommended for direct use. Resize Uint8Array with raw RGBA bitmap (don't confuse with jpeg / png / ... binaries). It does not use tiles & webworkers. Left for special cases when you really need to process raw binary data (for example, if you decode jpeg files "manually").
.filter
instead) - 0..3.mks2013
). See resize_filter_info.js for details. mks2013
does both resize and sharpening, it's optimal and not recommended to change.0
(off). Usually value between 100 to 200 is good. Note, mks2013
filter already does optimal sharpening.0
. Threshold for applying unsharp mask.pica
to create new one.Result is Promise, resolved with resized rgba buffer.
Pica has presets to adjust speed/quality ratio. Simply use quality
option param:
In real world you will never need to change default (max) quality. All this variations were implemented to better understand resize math :)
After scale down image can look a bit blured. It's good idea to sharpen it a bit. Pica has built-in "unsharp mask" filter (off by default). Set unsharpAmount
to positive number to activate the filter.
Filter's parameters are similar to ones from Photoshop. We recommend to start with unsharpAmount = 160
, unsharpRadius = 0.6
and unsharpThreshold = 1
. There is a correspondence between UnsharpMask parameters in popular graphics software.
We didn't have time to test all possible combinations, but in general:
Note. Though you can run this package on node.js
, browsers are the main target platform. On server side we recommend to use sharp.
You can find these links useful:
Available as part of the Tidelift Subscription.
The maintainers of pica and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source packages you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact packages you use. Learn more.
Author: Nodeca
Source Code: https://github.com/nodeca/pica
License: MIT License
1597469369
Crop and resize image size before upload in laravel using jquery copper js. In this post, i will show you how to crop and resize image size in laravel using jQuery copper js in laravel.
This laravel crop image before upload using cropper js looks like:
Laravel crop image before upload tutorial, follow the following steps and learn how to use cropper js to crop image before uploading in laravel app:
Read More => https://www.tutsmake.com/laravel-crop-image-before-upload-using-jquery-copper-js/
Live Demo Laravel Crop image Before Upload.
#laravel crop image before upload, #laravel crop and resize image using cropper.js #ajax image upload and crop with jquery and laravel #crop and upload image ajax jquery laravel #crop image while uploading with jquery laravel #image crop and upload using jquery with laravel ajax
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Resize image before upload using multer, sharp with node js and express js. In this node js tutorial, you will learn how to resize image before upload using multer, sharp with node js and express js.
Image upload is the basic requirement of any application. So this example will guide you step by step on how to resize image before upload using multer in node js. And you can understand a concept of node js compress image before upload.
Step 2 - Install Express and Multer Dependencies
Step 3 - Import Dependencies in Server.js File
Step 4 - Create Server.js File
Step 5 - Create Form
Step 6 - Run Development Server
https://www.tutsmake.com/node-js-resize-image-before-upload-using-multer-sharp-example/
#how to upload multiple image in node js #resize image in nodejs #image processing in node js #node js image upload resize