If i load TXT-Files on a reader Sony PRS-350, the reader generates a thumbnail by itself (Size maximum 217x217 pixels) after i disconnect the reader from USB. That thumbnail is a view of the first text page and doesn't look nice .
I create a new one (size adjusted to 217x217 pixels maximum) from the "cover.jpg" from the caliber database. Then i replace the "main_thumbnail.jpg" on the reader by the new one.
Is there a way to let calibre do that automatically?
