Spider

spider ... software that mechanically explores the web, transferring resources, and the resources that are linked to.

Pictures Spider

pictures spider ... software that mechanically explores the web, transferring resources, and the images that are linked to.

Nici is your personal picture spider. Enter the address of a web page and Nici spiders the pictures, saving them to your hard drive.

How to Spider Pictures

On the surface, Nici seems to calmly download picture after picture.

What you don't see is the Nici pictures spider busily spidering pictures and web pages. The basic chain of events is:

• Nici downloads the entry page, usually this is a page of html, if it is a picture Nici saves it to your computer.
• The external links and inline image links are extracted into a list. This list is reduced to a high probability list; those links that Nici believes are most likely to pictures. By not having to spider the full list, it saves time and bandwidth.
• The high probability list is passed to the pictures spider. Each link in the list is downloaded. If it is a picture, the picture is saved to your computer. If it is an html page. its links are analyzed, again creating another high probability list. (This is to handle thumb to html image galleries. An example of this is our Image Downloader example page). This list is also passed to the pictures spider.

Once the page and its pictures have been downloaded, this activity can be seen by opening the the "Download Control" window and switching to the "Report" tab.

Click to enlarge

The above screenshot was taken after Nici spidered and downloaded our example gallery: photo crawler.

The sequence of events described above (named the "Nici-Quick" strategy) is very efficient for downloading most picture galleries on the web. Usually the bare minimum of network request are made and 100% of your bandwidth is devoted to incoming pictures.

Controlling the Pictures Spider

For the 20% of galleries that the above (Nici-Quick) sequence does not get the pictures you want, you can try for more pictures, this time taking direct control of the picture spider.

To do this, open the "Download Control" window and switch to the "Crawl Settings". This is illustrated in the screenshot below:

Click to enlarge

Unlike the sequence of events described above, no high probability lists are created. Instead all links are spidered. You also need to set the "depth" that Nici will spider pictures. More exact instructions can be found by clicking on the "Help" button.