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NiLuJe · 07-14-2012, 06:28 PM

@kovidgoyal: Okay, good news: the weird "let's delete the thumbnail" issue I encountered yesterday indeed seems to be a weird caching issue (I was swapping existing books by deleting them from calibre, and reupping the same books in the same session).

If I delete them from the Kindle UI, everything's peachy. (I imagine it would also work correctly If I had deleted them from calibre, unplugged, let the Kindle refresh it's thing, plug, reup).

And it of course works correctly when upping *new* books

.

So, it doesn't hurt, the issue I had yesterday was unrelated

.

And you were right, the placement has nothing to do with it (and it is indeed quite a mess depending on the KG version, it's even messier with AZW3 files from Amazon, where we usually end up finding an UINT32_MAX in exth 125 or 131, the thumbnails uri sometimes != thumboffset, and we have another copy of the ASIN in exth 504...). Anyyyway...

Good news N°2: It works! If I send a book from Calibre with the no_sync option (so it doesn't get an ASIN), the Kindle properly build its custom thumbnail with the dropshadow, like with KindleGen files. (The file ends up in system/thumbnails like the rest, but with a slightly different name format: thumbnail_XXXXXX.jpg for calibre files, where X is an alphanumeric character, and thumbnail_NNNN.jpg for KG files, where N is a digit).

On the other hand, when there's an ASIN set, we still need Calibre's thumbnail, and that's the one that's used. (If I sideload a calibre built KF8 with an ASIN *outside* of Calibre, it ends up doing the exact same thing as when we sideload an AZW3 straight from Amazon (outside of calibre, still): No thumbnail until/unless Wireless is on, in which case it seems to be downloaded one way or another by the OS... And horribly fails if that's not a proper Amazon ASIN.

07-14-2012, 06:28 PM	#46
NiLuJe BLAM! Posts: 13,506 Karma: 26047202 Join Date: Jun 2010 Location: Paris, France Device: Kindle 2i, 3g, 4, 5w, PW, PW2, PW5; Kobo H2O, Forma, Elipsa, Sage, C2E	@kovidgoyal: Okay, good news: the weird "let's delete the thumbnail" issue I encountered yesterday indeed seems to be a weird caching issue (I was swapping existing books by deleting them from calibre, and reupping the same books in the same session). If I delete them from the Kindle UI, everything's peachy. (I imagine it would also work correctly If I had deleted them from calibre, unplugged, let the Kindle refresh it's thing, plug, reup). And it of course works correctly when upping new books . So, it doesn't hurt, the issue I had yesterday was unrelated . And you were right, the placement has nothing to do with it (and it is indeed quite a mess depending on the KG version, it's even messier with AZW3 files from Amazon, where we usually end up finding an UINT32_MAX in exth 125 or 131, the thumbnails uri sometimes != thumboffset, and we have another copy of the ASIN in exth 504...). Anyyyway... Good news N°2: It works! If I send a book from Calibre with the no_sync option (so it doesn't get an ASIN), the Kindle properly build its custom thumbnail with the dropshadow, like with KindleGen files. (The file ends up in system/thumbnails like the rest, but with a slightly different name format: thumbnail_XXXXXX.jpg for calibre files, where X is an alphanumeric character, and thumbnail_NNNN.jpg for KG files, where N is a digit). On the other hand, when there's an ASIN set, we still need Calibre's thumbnail, and that's the one that's used. (If I sideload a calibre built KF8 with an ASIN outside of Calibre, it ends up doing the exact same thing as when we sideload an AZW3 straight from Amazon (outside of calibre, still): No thumbnail until/unless Wireless is on, in which case it seems to be downloaded one way or another by the OS... And horribly fails if that's not a proper Amazon ASIN. Last edited by NiLuJe; 07-14-2012 at 06:45 PM.