#No way!
No way!
A few displays worth no more.
##A few displays worth no more. NoNo two devices have the same resources, be that due to hardware limits or current process requirements. You simply can not rely on client devices to give you more than a few screens worth of fast access pixel data. Even a top end machine may have resources tied up in other applications/processes and not be able to handle you page's need for fast random access pixels
##Consider the needs.
Consider the needs.
A million images at medium resolution (2MegPix) will require 1,000,000(Image count) * 2,000,000(pixel count) * 4(pixel channels) = 8e12 bytes (8Tb of RAM)
Nobody is going to download that much information, nor are any consumer level devices able to handle random access to such a large data store in any timely fashion.
##The solution
The solution
This type of application need to be coupled to a server.
The server holds all the images in a format that allows resolution independent access to the pixels (eg variation of wavelet image compression) the client then requests a view with details about the zoom and the server delivers the images at the resolution required.
At no time does the client need to store more than the display size worth of pixels.
Some examples of this approch are Google Earth / Google Maps and Microsoft's TerraServer