Previously, I used KOReader's notes and highlight export function to export as markdown and store them in my Obsidian vault (I've contributed to its development too). I export with styles so that they give me context later. It is very convenient. However, sometimes, it is also hard to read. In Obsidian we have callouts which is not standard markdown, and therefore, is not a good candidate to add support for it in the KOReader directly. So I decided to export as JSON from KOReader and use that JSON to generate markdown the way I like.

I'm using the script below to achieve my goal. Save this as a template and call it with the Templater plugin.

<%*
// The KOReader defined highlight styles vs callout mapping. Leave the keys as is, but you can edit the values to create your own convention.
const NOTE_STYLES = {
  lighten: {
	type: "quote",
	title: "Quotable/Concept/General Idea",
  },
  invert: {
	type: "important",
	title: "Striking/Intense",
  },
  strikeout: {
	type: "danger",
	title: "In Discord",
  },
  underscore: {
	type: "question",
	title: "Thought Provoking",
  },
};

function format_koreader_percentages(page, total) {
	if (page && total) {
		return `${((page / total) * 100).toFixed(2)}%`;
	}
	return "";
}

function format_koreader_json_highlights(content) {
	const data = JSON.parse(content);
    let output = `---
title: "${data.title}"
aliases: ["Notes from ${data.title}"]
author: "${data.author}"
---
# ${data.title}
##### ${data.author}`;
	let current_chapter = "";
	for (const entry of data.entries) {
	  if (entry.text) {
		if (entry.chapter != current_chapter) {
		  output += `\n\n## ${entry.chapter}\n`;
		  current_chapter = entry.chapter;
		}
		output += `\n### Page: ${
		  entry.page
		} (${format_koreader_percentages(
		  entry.page,
		  data.number_of_pages
		)}) @ ${window.moment.unix(entry.time).format("DD MMM YYYY hh:mm:ss A")}\n`;
		output += `\n${entry.text}`;
		const note_type = NOTE_STYLES[entry.drawer];
		output += `\n\n> [!${note_type.type}] ${note_type.title}`;
		if (entry.note) {
		  if (entry.note.length > 50) {
			output += `\n> ${entry.note}`;
		  } else {
			output += `: ${entry.note}`;
		  }
		  output += "\n";
		}
		output += "\n";
	  }
	}
	return output;
}

const content = await tp.system.prompt("Paste the JSON content", null, true, true);
const output = format_koreader_json_highlights(content);
let file = app.workspace.getActiveFile();
await app.vault.modify(file, output);
%>

It will prompt you to paste the JSON. open the JSON file and copy-paste the content in the prompt.

An Example

Here's an exported JSON file I used to generate a note from:

{
	"number_of_pages": 68,
	"file": "/storage/emulated/0/Download/(Shambhala Centaur Editions) Sam Hamill - The Sound of Water_ Haiku by Basho, Buson, Issa, and Other Poets.epub",
	"author": "Sam Hamill",
	"entries": [
		{
			"chapter": "Cover",
			"text": "books from ancient Chinese, Japanese, Greek, Latin, and Estonian. He has published fourteen volumes of original poetry. He has been the recipient of fellowships from the National Endowment for the Arts, the Guggenheim Foundation, the Woodrow Wilson Foundation",
			"time": 1694256612,
			"sort": "highlight",
			"page": 2,
			"drawer": "lighten"
		},
		{
			"chapter": "Translator’s Introduction",
			"text": "authentic experience of “beeness” as deeply as possible? Perhaps both qualities are present. His detailed observation calls for something other than metaphor; it demands literal accuracy. Is the bee inside his mind or outside? The poem moves in part because of tension raised",
			"time": 1694256620,
			"sort": "highlight",
			"page": 9,
			"drawer": "underscore"
		},
		{
			"chapter": "Translator’s Introduction",
			"note": "some note Page 10 to write a quatrain or a sonnet. The problem remains: to be great, a poem must rise on its own merit, and too much haiku is merely haiku.",
			"text": "to write a quatrain or a sonnet. The problem remains: to be great, a poem must rise on its own merit, and too much haiku is merely haiku. Haiku written in American English and attempting to borrow traditional Japanese literary devices usually ends up smelling of the bric-",
			"time": 1694256629,
			"sort": "highlight",
			"page": 10,
			"drawer": "strikeout"
		},
		{
			"chapter": "Translator’s Introduction",
			"text": "follow in the footsteps of the old masters, but seek what they sought.” His “way of elegance” did not include the mere trappings associated with elegance; he sought the authentic vision of “the ancients.”\nBorn into a samurai family prominent among nobility, Bashō rejected that world and became a wanderer, studying Zen, history, and classical Chinese poetry, living in apparently",
			"time": 1694256653,
			"sort": "highlight",
			"page": 11,
			"drawer": "invert",
			"note": "a very small striking thing"
		}
	],
	"title": "The Sound of Water",
	"created_on": 1694256681,
	"version": "json/1.0.0"
}

And, It generated the following content:

---
title: "The Sound of Water"
aliases: ["Notes from The Sound of Water"]
author: "Sam Hamill"
---
# The Sound of Water
##### Sam Hamill

## Cover

### Page: 2 (2.94%) @ 09 Sep 2023 04:50:12 PM

books from ancient Chinese, Japanese, Greek, Latin, and Estonian. He has published fourteen volumes of original poetry. He has been the recipient of fellowships from the National Endowment for the Arts, the Guggenheim Foundation, the Woodrow Wilson Foundation

> [!quote] Quotable/Concept/General Idea


## Translator’s Introduction

### Page: 9 (13.24%) @ 09 Sep 2023 04:50:20 PM

authentic experience of “beeness” as deeply as possible? Perhaps both qualities are present. His detailed observation calls for something other than metaphor; it demands literal accuracy. Is the bee inside his mind or outside? The poem moves in part because of tension raised

> [!question] Thought Provoking

### Page: 10 (14.71%) @ 09 Sep 2023 04:50:29 PM

to write a quatrain or a sonnet. The problem remains: to be great, a poem must rise on its own merit, and too much haiku is merely haiku. Haiku written in American English and attempting to borrow traditional Japanese literary devices usually ends up smelling of the bric-

> [!danger] In Discord
> some note Page 10 to write a quatrain or a sonnet. The problem remains: to be great, a poem must rise on its own merit, and too much haiku is merely haiku.


### Page: 11 (16.18%) @ 09 Sep 2023 04:50:53 PM

follow in the footsteps of the old masters, but seek what they sought.” His “way of elegance” did not include the mere trappings associated with elegance; he sought the authentic vision of “the ancients.”
Born into a samurai family prominent among nobility, Bashō rejected that world and became a wanderer, studying Zen, history, and classical Chinese poetry, living in apparently

> [!important] Striking/Intense: a very small striking thing