IS there a better way? Image Thumbnails

tony_l

I am storing my images in a mysql database using PHP 5.

My script is working beautifully, BUT now I want to store the thumbnails in a database as well. I was doing thumbnails on the fly on the display page, but it seems to be slow as molasses.

SO.....

I was thinking HOW would I do that?

I have a thumbnail function that I got off of this site, but it is for writing thumbnails to a file. I was thinking I could modify it, but I am not sure how to do it efficiently.

This is what my site does so far....

User uploads a file.
Script then puts that file into a MySQL (5.0) database.
I have a page that displays the image using the header function.

Has anyone done this before, or have any ideas hows to write the resized file to the database in an efficient manner?

Thanks, Tony

Weedpacket

Saving them to a file would be more efficient than storing them in the database. More flexible too. And easier.

At least, that's how I find it; use the forums' search facility a bit and see what other points of view there are (use the search terms "save", "image" and "database").

karthikeyan

i hope this one might help ... http://thephpforum.net/viewtopic1265

tony_l

Thanks for the link to the class.

I am using a database to store the images. I know that there is debate over whether or not to store images in a database, but my view is that the image in a database is better accessed due to the ability to search the database for an image you want. Also database records are rarely deleted by accident when someone decides to move a file or delete a folder. If you use files in folders, it is difficult to upload the files due to some server configurations - such as having to use FTP.

Thanks for the input guys

cnperry

I know this post is well after the fact, but it's typically considered best practice to NOT store images in a database. Also, the file upload restrictions (i.e. file size) are often more an Apache thing than a PHP thing. On many hosts maximum POST file sizes is between 2-4MB, and thus a problem even before PHP has a chance to see the file. You're right - it can be annoying when stupid things like safe_mode are turned ON, but there are still work-arounds like creating a directory in the user writable space and creating a symbolic link from the web root to that directory. I've had to do that on a couple projects. Finally, you aren't going to gain better searches by having binary data in the database. If anything it'll slow down DB access at some point. All you need to do is store image's location in the file system and create a simple

<img src="<?$image_path?>" alt="my image" />

That's all - just my two cents.

karthikeyan

yes file type, size, upload dir, permissions are main things

MarkR

You can certainly store thumbnails in the database as well - just store the width, height and blob of the thumbnail in the same table (That's what I'd do).

As far as serving them is concerned, you'll need a PHP page which fetches the thumbnail (probably by ID, e.g. thumbnail.php?id=42). Because a page is likely to contain a lot of thumbnails, it's important that this script handles client-side caching properly. The thumbnail of an image is never likely to change (You'd allocate a new ID for a new image, right?), so it's worth adding a last-modified and expires: header, as well as fixing up any other headers you need to ensure that the browser will cache the thumbnail where possible.

Not caching thumbnails will result in slow page loads, as the browser must get all the thumbnails each time.

Mark

Weedpacket

tony_l wrote:
but my view is that the image in a database is better accessed due to the ability to search the database for an image you want.

I was meaning to ask: how do you search images in the database?

MarkR

Sorry to hijack this thread slightly-

But for me the advantage of storing images in a database is one of managability - all the data are in the same place and can't get lost, separated or mixed up, e.g. in dev / staging / production.

Of course managing a large number of files in the filesystem is possible (not even particularly difficult), and there are probably some performance arguments for it (I'm not denying this), but having them in the database is convenient for (e.g.) backups and other management.

Mark

Rodney_H_

/ off topic, sorry... /

In my opinion, images are not data. Images are assets and resources. Information ABOUT images is, however, data.

Therefore, for me, I see how storing INFO about images in a database is a good idea, but storing the actual file on the server is the way to do it. I wouldn't save all our PDFs and DOCs (etc) in the database as binary either, but I would save info about them in the db so users may search and find different types of file assets...

Again, just my opinion, LOL!!

zabmilenko

Listing the name of the original image file in the database should be sufficient. Then, use is_readable() to see if a cached thumbnail is written to disk already. If not, then the thumbnail generator can go to work, otherwise the link to the thumbnail is passed.