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Image Download Help

Instructions

• To determine what image files you need for a particular loop, you must first know how many times per day that the chart is produced. You can find that information at the Available Products page.



• You then need to decide how many days that you want in your loop. The available selections for most products are 3, 7, and 14 days. The two exceptions to this are the W Atlantic and E Pacific Wind & Wave Analyses. They both have selections of 3, 7, and 12 days.



• Multiply the number of times that a chart is produced per day by the number of days in the loop. For the purpose of these instructions, I shall call this number "N" (N = [charts per day] * [# of days in the loop]). For example, if I wanted to loop a chart that is produced 4 times per day in a 7 day loop, I multiply 4 (charts/day) by 7 (days). The result is 28 charts (N = 28). This means that I need to save 28 image files for the loop to work correctly.



• The most recent image file in all of the Product Loop directories is always called "image01.gif". The age of the chart increases sequentially with the number in the filename (imageXX.gif). Recall the number "N" that you calculated in the previous instruction. For your loop to work correctly, you need to save files "image01.gif" through "image(N).gif". In my previous example, I needed 28 images (N = 28). For my example loop to work correctly, I would need to save files "image01.gif" through "image28.gif".