This information is available in the Google document [https://docs.google.com/document/d/1UHFpVuuMCG2eOtNhpXlBbuqmxjbzwEIayPzZiXPq9W8/edit?tab=t.0 Guide to buy and rip books from Rakuten Books].
This information is available in the Google document [https://docs.google.com/document/d/1UHFpVuuMCG2eOtNhpXlBbuqmxjbzwEIayPzZiXPq9W8/edit?tab=t.0 Guide to buy and rip books from Rakuten Books].
== Notes on canvas ripping ==
== Canvas ripping ==
The sample size here is 1, so this information might not be accurate for all manga. For the volume I did try, I found some things:
Canvas ripping involves obtaining raws by extracting image content from its already-rendered form on the website.
Advantages:
* It usually can be performed with just a web browser and no external software.
* It doesn’t rely on DRM-cracking shenanigans.
* If you know a bit of web dev these methods are very easy to develop and modify.
Disadvantages:
* Might involve more manual work than some methods (though it’s still fast anyway).
* The resulting files will be PNG files instead of the original JPEGs/WEBPs, and are thus generally larger (you can use [https://yuri-project.net/tools/compress our image compression tool] to reduce their size a little, but it still won’t be as small).
* You have to be careful to avoid resampling, as if the images are resized on the website before you download them, quality is reduced.
If you want to use canvas-ripping, here is a brief comparison of some online bookstores that I compared for this purpose:
* BookWalker: Inserts a barcode onto pages. This is hard to remove as it can cover the art, including screentones. It can be annoying to resize the window to the right size such that the image is at its native resolution.
* BookWalker: Inserts a barcode onto pages. This is hard to remove as it can cover the art, including screentones. It can be annoying to resize the window to the right size such that the image is at its native resolution.
Line 91:
Line 103:
* BookLive: Slightly lower quality than BookWalker (at least in the preview), but very easy to scrape from.
* BookLive: Slightly lower quality than BookWalker (at least in the preview), but very easy to scrape from.
All the below Javascript snippets can be easily formatted and understood. So if you know a little Javascript it’d be pretty easy to adapt them to whatever site you want to canvas rip from. The resulting PNGs are quite large – you may want to reduce their size with oxipng, which can be done via [https://yuri-project.net/tools/compress our compression tool].
For each site, we give a code snippet that scrapes from that site. The intended usage is to save the code snippet as a bookmark in your web browser, click the bookmark while looking at the site, and then scroll through the manga to download all of the pages. Alternatively, you can go open developer tools (e.g. via inspect element) and paste the snippets in the “Console” tab.
=== BookLive ===
=== BookLive ===
This bookmarklet can also be used for cmoa. Open the manga, put it in vertical orientation, click the bookmarklet and then start scrolling down. Tested on 2025-08-22.
This bookmarklet can also be used for cmoa. Open the manga, put it in vertical orientation, click the bookmarklet and then start scrolling down. Tested on 2025-08-22. If your viewport is sufficiently wide, I believe there should not be resampling issues.
<pre>
<pre>
Line 111:
Line 123:
=== Take Comic ===
=== Take Comic ===
Tested on a free chapter on 2025-10-17.
To prevent resampling, follow these steps:
<pre>
javascript:(()=>{const a=document.createElement("a"),q=new Map;let i=0;for(const p of document.querySelectorAll("#xCVPages>.-cv-page"))q.set(p,i++);setInterval(()=>{for(const p of document.querySelectorAll(".-cv-page.mode-rendered")){if(!q.has(p))continue;a.href=p.querySelector("canvas").toDataURL(),a.download=`${q.get(p)}.png`.padStart(7,"0"),a.click(),q.delete(p)}},100)})()
</pre>
Getting the original resolution (for maximum quality) can be hard. I found the following steps to work:
<ol>
<ol>
Line 130:
Line 136:
</pre>
</pre>
In these three lines, replace both instances of <code>y * b</code> with <code>r</code>, and both instances of <code>w * b</code> with <code>i</code> (of course, adjust accordingly if these variables have different names).</li>
In these three lines, replace both instances of <code>y * b</code> with <code>r</code>, and both instances of <code>w * b</code> with <code>i</code> (of course, adjust accordingly if these variables have different names).</li>
<li>Save the file and reload the page. Now the bookmarklet should download images of the original resolution.</li>
<li>Save the file and reload the page.</li>
</ol>
</ol>
Now use the bookmarklet:
<pre>
javascript:(()=>{const a=document.createElement("a"),q=new Map;let i=0;for(const p of document.querySelectorAll("#xCVPages>.-cv-page"))q.set(p,i++);setInterval(()=>{for(const p of document.querySelectorAll(".-cv-page.mode-rendered")){if(!q.has(p))continue;a.href=p.querySelector("canvas").toDataURL(),a.download=`${q.get(p)}.png`.padStart(7,"0"),a.click(),q.delete(p)}},100)})()
</pre>
Tested on a free chapter on 2025-10-17.
=== BookWalker ===
=== BookWalker ===
Revision as of 22:48, 17 October 2025
The first step in the process of scanlating any manga is obtaining the raws. The first step is to download the file the raws are in, then the second step is to extract the raws from this file.
Raws can often be found on piracy websites dedicated to hosting them (none are listed here to avoid link rot, but they can be found on the Internet). They are often lower quality than ripping the raws yourself, so this is not preferred. Be aware that some websites will add watermarks; since it is best practice to not keep watermarks from these sites (the only kind of acceptable watermark is an author watermark), one will either have to manually clean them or find a different source.
Useful tools
There are some general-purpose manga downloading tools; a notable one is HakuNeko. Alex's Raw Downloader is really simple to use for sites that it's compatible with (click "Info" on the site for a full list of compatible sites).
Websites that allow online viewing of manga will often render the images in a <canvas> element, which can then be extracted with browser extensions like Canvas Downloader for Chrome, ImageAssistant for Chrome or Image Picka for Firefox, or using bookmarklets. Be aware that resampling may occur. Some websites like Bookwalker add a near-invisible barcode at the bottom that points to your account; one should take care to remove the 3 bottom pixels of all pages.
A useful tool is this Stack Overflow answer which provides a script/bookmarklet that re-enables the ability to right-click on websites that have disabled it.
Screenshotting
Usually an easy way, but can be low quality due to the resampling that may occur, and is labor-intensive.
PDF
PDF raws are most common when obtaining self-published raws from websites such as https://booth.pm/en
Most raw PDFs are single pages with the images embedded in each page. So the next step is to extract the images that are embedded. There are two tools that are often used.
This will output the files in the same directory as the file. Change the final argument to change the path of the output directory.
Bookwalker
This requires downloading a modified Chromium executable on a Windows computer and the ability to run a PowerShell command.
Warning: The Chromium client downloaded here bypasses safety features and should not be used for anything other than downloading manga from Bookwalker.
These instructions apply to the latest version at the time of writing, version 0.3.3:
Bookwalker window sized for downloadingBuy the manga on Bookwalker. For most Japanese releases, you will need to use the Japanese site, not the global site.
Open a powsershell or cmd in the unzipped browser dir:
Navigate to the unzipped directory in explorer.
Shift + right-click in the folder.
Select "Open PowerShell window here".
Open the browser with command line: .\chrome.exe --user-data-dir=c:\bw-downloader-profile --no-sandbox
Log into you Bookwalker account in the launched Chromium window.
Open the book you want to rip in the viewer.
Adjust the window so exactly one page is visible.
If you can get the script to automatically click (step 6 here), that's good, but it is not working at the time of writing due to Bookwalker code changes.
Instead, you can just click through the manga you are ripping, one page at a time (giving each page enough time to load).
After you've clicked through all the pages you want to rip, the pages will be in C:\bw_export_data under a folder with a name matching the ID in the Bookwalker URL.
Creating a shortcut
Creating a shortcut for Bookwalker downloader Chromium
To create a shortcut that launches the modified Chromium application with the appropriate permissions:
Right-click on chrome.exe and select "Create shortcut".
Right-click on the new shortcut and select "Properties".
Select "Target" and move the cursor to the end.
Paste --user-data-dir=c:\bw-downloader-profile --no-sandbox (including the space before)
The new "Target" should look like C:\path\to\Chrome-bin\chrome.exe --user-data-dir=c:\bw-downloader-profile --no-sandbox.
Canvas ripping involves obtaining raws by extracting image content from its already-rendered form on the website.
Advantages:
It usually can be performed with just a web browser and no external software.
It doesn’t rely on DRM-cracking shenanigans.
If you know a bit of web dev these methods are very easy to develop and modify.
Disadvantages:
Might involve more manual work than some methods (though it’s still fast anyway).
The resulting files will be PNG files instead of the original JPEGs/WEBPs, and are thus generally larger (you can use our image compression tool to reduce their size a little, but it still won’t be as small).
You have to be careful to avoid resampling, as if the images are resized on the website before you download them, quality is reduced.
If you want to use canvas-ripping, here is a brief comparison of some online bookstores that I compared for this purpose:
BookWalker: Inserts a barcode onto pages. This is hard to remove as it can cover the art, including screentones. It can be annoying to resize the window to the right size such that the image is at its native resolution.
cmoa: Lower quality than Bookwalker, at least in the preview.
k-manga: The preview resized the image 4px smaller than the original resolution, which really messes up screentones.
Kobo: Region-locked, so I didn’t try it (it’s possible to insert fake details to get around the region lock).
BookLive: Slightly lower quality than BookWalker (at least in the preview), but very easy to scrape from.
For each site, we give a code snippet that scrapes from that site. The intended usage is to save the code snippet as a bookmark in your web browser, click the bookmark while looking at the site, and then scroll through the manga to download all of the pages. Alternatively, you can go open developer tools (e.g. via inspect element) and paste the snippets in the “Console” tab.
BookLive
This bookmarklet can also be used for cmoa. Open the manga, put it in vertical orientation, click the bookmarklet and then start scrolling down. Tested on 2025-08-22. If your viewport is sufficiently wide, I believe there should not be resampling issues.
javascript:(()=>{const done=new Set,a=document.createElement("a"),cv=document.createElement("canvas"),c2=cv.getContext("2d");setInterval((()=>{for(const t of document.getElementById("content").children){if(!t.id.startsWith("content-p"))continue;const e=t.id.slice(9).padStart(3,"0");if(done.has(e))continue;const n=[...t.getElementsByTagName("img")];if(0===n.length||n.some((t=>!t.complete)))continue;const c=n.map(((t,e)=>{if(e===n.length-1)return[t,t.naturalHeight-2];const a=t.getBoundingClientRect(),c=n[e+1].getBoundingClientRect();return[t,Math.round((c.y-a.y)/a.height*t.naturalHeight)]}));cv.width=Math.max(...n.map((t=>t.naturalWidth))),cv.height=c.reduce(((t,[e,n])=>t+n),0);let o=0;for(const[t,e]of c)c2.drawImage(t,0,o),o+=e;a.href=cv.toDataURL(),a.download=`${e}.png`,a.click(),done.add(e)}}),100)})()
Zero Sum Online
Tested on 2025-02-03.
javascript:(()=>{const t=new Set,e=document.createElement("a"),a=document.createElement("canvas"),n=a.getContext("2d");setInterval((()=>{for(const c of document.getElementsByTagName("img")){if(!c.classList.item(0)?.endsWith("_page")||!c.alt.startsWith("page_")||!c.complete)continue;const o=c.alt.slice(5).padStart(3,"0");t.has(o)||(a.width=c.naturalWidth,a.height=c.naturalHeight,n.drawImage(c,0,0),e.href=a.toDataURL(),e.download=`${o}.png`,e.click(),t.add(o))}}),100);})()
Take Comic
To prevent resampling, follow these steps:
Open developer tools (e.g. using inspect element), go to the Sources tab, and open the “Page” sub-tab on the left.
On the left sidebar, find the file top → takecomic.jp → js/viewer → viewer.js. Right-click it and select “Override Content”.
Press the {} button in the bottom-left of the middle panel to see the code.
Press Ctrl+F, and search for “drawImage”. There should be a section that says something along the lines of:
o.width = y * b,
o.height = w * b,
s.drawImage(c, 0, 0, r, i, 0, 0, y * b, w * b),
In these three lines, replace both instances of y * b with r, and both instances of w * b with i (of course, adjust accordingly if these variables have different names).
Save the file and reload the page.
Now use the bookmarklet:
javascript:(()=>{const a=document.createElement("a"),q=new Map;let i=0;for(const p of document.querySelectorAll("#xCVPages>.-cv-page"))q.set(p,i++);setInterval(()=>{for(const p of document.querySelectorAll(".-cv-page.mode-rendered")){if(!q.has(p))continue;a.href=p.querySelector("canvas").toDataURL(),a.download=`${q.get(p)}.png`.padStart(7,"0"),a.click(),q.delete(p)}},100)})()
Tested on a free chapter on 2025-10-17.
BookWalker
This does not remove the barcodes, so use with caution. I’m putting it here because the same techniques can likely be used on other sites. As with BookLive, put the reader in vertical mode and make sure the images are at their native resolution. Tested on 2025-02-03.
javascript:(()=>{const done=new Set,a=document.createElement("a");setInterval((()=>{for(const e of document.getElementById("canvasCluster").children){if(!e.id.startsWith("wideScreen"))continue;const t=e.id.slice(10).padStart(3,"0");if(done.has(t))continue;const n=e.children[1];255===n.getContext("2d").getImageData(0,0,n.width,n.height).data[3]&&(a.href=n.toDataURL(),a.download=`${t}.png`,a.click(),done.add(t))}}),100);})()