Anyone, please point me in a right direction.

I want to add a new tab to ImageUploadField, and to place there a field to enter a timecode, and button to get preview from FLV attached via FileUploadField above, as shown in the image:

I've extended ImageUploadField and set a new template for it, with code for butrton as:

<button type="submit" class="{'url' : '$Link(extract)'}">Extract from video</button>

But where (in which class) to place a "function extract(...)" and why Firebug console shows corresponding request as
http://localhost/zavod/admin/EditForm/field/Media/item/3/DetailForm?SecurityID=...
i.e. without /extract chunk after "DetailForm"?

Thank you in advance, and sorry for not so good English...

I assume you have created a subclass of ImageUploadField? The function can go in there. Form fields are actually controllers. Just don't forget to add the "extract" action to your allowed_actions, too.

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