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pssquirrel · 12-12-2014, 11:53 AM

Thanks for all the links, Doitsu! I've played around with converting epub to azw3 using Kindle Previewer, and I've exploded a few azw3s with the KindleUnpack Calibre plug-in. I was happy to find that I recognized all the parts of an exploded azw3. I'll check out the Sigil plug-in.

Here's what I'm trying to learn:

I know that epubs are just a collection of text/html files compressed into a slightly modified zip file. I like that you can unzip them using standard/generic software, edit with any text editor, then rezip them. From my understanding, it's a lossless process. This plus the fact that it's an open format appeals to me. When you use KindleUnpack to explode an azw3, are the resulting files lossless? Have they been modified or converted in some way, or were they simply decompressed or unwrapped?
After playing around, I discovered that if I insert a valid ASIN in the opf, then use Calibre's Quality Check to "Fix ASIN for Kindle Fire," I can transfer the file via straight drag-and-drop (no Calibre "send to device") and my Voyage will download a cover image from Amazon's servers. (The ASIN doesn't even have to match the metadata in the opf -- if the book is "Alice in Wonderland" and I input the ASIN for Tom Clancy's latest bestseller, I will get the cover for the Tom Clancy bestseller. Also, simply inserting an ASIN in the opf doesn't work; I have to run "Fix ASIN for Kindle Fire" to get a cover.)

What I would like to know is, what does "Fix ASIN for Kindle Fire" do? I dug into some other posts that talked about editing CDEContentType and EXTH 113 & 504, but when I looked in the opf and other exploded files, I found nothing like that. Am I guessing correctly that "Fix ASIN for Kindle Fire" edits hidden files or hidden data not accessible in an exploded azw3? Is there a way to "Fix ASIN" manually?
As far as I can tell, KindleGen/KindlePreviewer is a one-way process where you feed data in and an azw3 comes out, yes? You can't use it to open up an azw3 for editing? If you want to edit, you have to go back to the source data, edit that, and then run it through KindleGen/KindlePreviewer to make a new azw3?

Again, I know it's easiest to just use Calibre. I'm asking because I like to understand these things

Thanks everyone for indulging my curiosity!

12-12-2014, 11:53 AM	#10
pssquirrel ebooknut Posts: 297 Karma: 688154 Join Date: Oct 2011 Device: Kindle Voyage & Oasis	Thanks for all the links, Doitsu! I've played around with converting epub to azw3 using Kindle Previewer, and I've exploded a few azw3s with the KindleUnpack Calibre plug-in. I was happy to find that I recognized all the parts of an exploded azw3. I'll check out the Sigil plug-in. Here's what I'm trying to learn: I know that epubs are just a collection of text/html files compressed into a slightly modified zip file. I like that you can unzip them using standard/generic software, edit with any text editor, then rezip them. From my understanding, it's a lossless process. This plus the fact that it's an open format appeals to me. When you use KindleUnpack to explode an azw3, are the resulting files lossless? Have they been modified or converted in some way, or were they simply decompressed or unwrapped? After playing around, I discovered that if I insert a valid ASIN in the opf, then use Calibre's Quality Check to "Fix ASIN for Kindle Fire," I can transfer the file via straight drag-and-drop (no Calibre "send to device") and my Voyage will download a cover image from Amazon's servers. (The ASIN doesn't even have to match the metadata in the opf -- if the book is "Alice in Wonderland" and I input the ASIN for Tom Clancy's latest bestseller, I will get the cover for the Tom Clancy bestseller. Also, simply inserting an ASIN in the opf doesn't work; I have to run "Fix ASIN for Kindle Fire" to get a cover.) What I would like to know is, what does "Fix ASIN for Kindle Fire" do? I dug into some other posts that talked about editing CDEContentType and EXTH 113 & 504, but when I looked in the opf and other exploded files, I found nothing like that. Am I guessing correctly that "Fix ASIN for Kindle Fire" edits hidden files or hidden data not accessible in an exploded azw3? Is there a way to "Fix ASIN" manually? As far as I can tell, KindleGen/KindlePreviewer is a one-way process where you feed data in and an azw3 comes out, yes? You can't use it to open up an azw3 for editing? If you want to edit, you have to go back to the source data, edit that, and then run it through KindleGen/KindlePreviewer to make a new azw3? Again, I know it's easiest to just use Calibre. I'm asking because I like to understand these things Thanks everyone for indulging my curiosity! Last edited by pssquirrel; 12-12-2014 at 11:56 AM.