Alexandru Vornicescu

This is a WordPress plugin.
If you want to resize images in your posts automatically so the page will load faster and use less bandwidth then this plugin can help you.
To take effect just open a post or page and all images in that post will be resized to a smaller version.
It will replace the URLs of the images that are too big with URLs of the resized images that will fit into the posts.
The plugin will keep the original copy of all image files.
Note: With version 4.3 now you can resize images in Text Widgets.
Note: The filter – “wp_make_content_images_responsive” will be deactivated because with this plugin we will not need anymore.

Resize Images In Posts

This plugin will resize images in your posts.

llvasconcellos

*** ATENTION ***
Due to modifications on the Media Library the plugin only works with the “UPLOAD NEW MEDIA” form located under Media -> Add New menu entry on the left menu. If you click direct on Media and use the Add New button of MEDIA LIBRARY the plugin will not be executed.
I filled a bug report here: 
https://core.trac.wordpress.org/ticket/39492
With this plugin you can use High Resolution images directly from your camera to WordPress without using any additional software to resize them. You only have to use a HTML5 capable browser.
<ul>
<li>Works with Drag & Drop!</li>
</ul>
Exemple of capable browsers are: Chrome, Firefox, Opera, IOS e Android.
It will add extra media settings at SETTINGS -> MEDIA where you can specify resized JPG quality and maximum width and height for each uploaded image.
Brought to you by DevHouse – Internet Software Development House: http://www.devhouse.com.br
Com este plugin você pode usar diretamente as imagens em alta resolução diretamente da sua câmera digital diretamente para o WordPress sem a necessidade de passar por softwares adicionais para redimensioná-las. Basta ter um browser atualizado.
<ul>
<li>Funciona com Drag & Drop!</li>
</ul>
Exemplos de Browsers são: Chrome, Firefox, Opera, IOS e Android.
Ele adicionará configurações adicionais em CONFIGURAÇÕES -> MÍDIA onde você pode especificar a qualidade do JPG redimensionado e largura e altura máximas para cada imagem enviada.
Trazido para você por DevHouse – Internet Software Development House: http://www.devhouse.com.br

Client Side Image Resize

Uses HTML5 to resize large images before uploading to server.

Resize Images In Posts vs Client Side Image Resize