A Question About Image Files

I am writing an PHP script to upload image files to the server and I have a few questions?

Is there a way to decrease the size of images in terms of kilobyt开发者_StackOverflowes?

When I am using those files what is the best practice to embed those images into page? I mean do I always have to download the whole page?

Lastly, When resizing the pages(like 250X250 pixels) what is the pratice in order not to face the resolution problems?

I hope my questions are not too general. Thanks in advance!

Take a look at this http://www.webmotionuk.co.uk/php-jquery-image-upload-and-crop/ - There are many other free tools out there to convert images after the upload. The resolution shouldn't be an issue that is usually a problem when you give a size to an image object in html that is huge and not proportioned.

Here is another php resizer I have used this code before to do what you are requesting.

Is there a way to decrease the size of images in terms of kilobytes?

You'll need to create a new image, based on the one you received. You should first take a look at the PHP GD functions.

For instance: http://ch2.php.net/manual/en/function.imagecreatefromjpeg.php

When I am using those files what is the best practice to embed those images into page? I mean do I always have to download the whole page?

What do you mean by embedding?

If you are talking about decreasing the size of the image before is uploaded, you can't with PHP, unless you use something like HTML5/Flash to pre-process the file before being sent.

What you want to do, after a user uploads that image, verify that the file is a real image, then using some library (if you use a framework, it probably has a way to resize images) resize the image to whatever max width or max height or max width and height you are wanting.

This will decrease the size of an image.

For the 2nd question, if I understand it, you are talking about what about when a user uploads a 500x500 and you want it to be 400x250, then you must scale and crop, this way the image is never stretched but a few pixels from the top or the bottom will probably be removed.