Best practice to add an image

[Hitch]

Originally Posted by j.p.s

As I wrote some of the images look good on any screen, some of them are about as good as any I've seen in e-books so far, not that I have seen more than a very tiny fraction of e-books, but I've seen enough to have an idea of what is typical.

The tables, which are images, look bad on any screen, except for the last image of the list of consuls, which was pretty good, maybe even overkill, except for the JPEG artifacts.

I have seen similar tables in other books that are much worse, but these could have easily been a lot better at the same resolution. And I think these are still a good example of how not to do it.

Well, THAT was weird. I clicked your link, and suddenly, I was in YOUR Amazon account. You might want to modify that link. (I realized it after I noticed that the only "reader" available to me was the KCR, not my usual devices.)

Hitch

[radius]

Not best practices, but this is what I do for my personal reading enjoyment:

- if I can get away with it, I turn the picture into straight, 1-bit, black and white. This works fairly well for scans of illustrations from pulp magazines and paperbacks. Doing it this way does risk losing some detail and it can be difficult to find the right cutoff level. However, I think it looks the best on an actual e-ink display.

Even 12 inch tablets top out around the 1200x1600 mark right now so I scale the image to fit within that before messing with the colour.

I save these as 1-bit gif or png depending on what my fingers feel like typing on that day.

- if the original illustration was in colour, or in delicate gray scale, then I try to boost contrast and then do a dithered conversion to 4-bit gray scale. This requires some trial and error because it won't look good on a computer monitor.

I do the conversion to gray scale because I believe that computer-based graphics programs can do a better job with the re-scale and colour conversion than an eink reader can do on the fly, since the reader will have to be optimised also for speed of display.

I save these are png if there aren't too many illustrations and/or they aren't too big. If I am having trouble with the size of the epub, then I might choose jpg, but then I don't bother with quantizing to only 16 grey levels and only do the contrast boost.

An example of this kind of image might be some of the Ruritanian trilogy ones.

- if I am making an "archival" book, then I just save the largest and best quality image file that I can get.


I'll try to add some example images to this post when I get home.

[jhowell]

Originally Posted by j.p.s

To get back on track, I can give an example of a 2015 e-book with a mix of really good and really bad images. It is currently $1.30 at amazon US and a free sample almost certainly has the tables that are the worst and likely has a couple of maps.

https://www.amazon.com/Marcus-Agripp.../dp/B00TOXQLDY

The multi-page "Chronology" and "List of Consuls" tables are scanned images with poor contrast and bad JPEG artifacts. Interestingly, the bottom of the "List of Consuls" table only takes up a few lines at the top of a page and was scanned with significantly higher resolution and better contrast, although the JPEG artifacts are little better.

I took a look at the List of Consuls in the free sample of the book you mentioned. From what I could see, Amazon is likely to be responsible for the image quality issues that you mentioned in that book. The original version provided by the publisher to Amazon used high quality images.

With Kindle books a lot depends on the device to which the book is being delivered and the format used. I looked at the sample in two different formats, KF8 (azw3) and KFX, both downloaded using Kindle for PC. I compared the total file size of the sample and the size and resolution of the JPEG images that make up the List of Consuls. The images in the KFX version were noticeably clearer with fewer artefacts and are likely closer to what the publisher originally provided.

The KF8 version was 1.4MB and the images were 932x1117 (126KB), 789x1340 (119KB), and 1638x444 (110KB).

The KFX version was 12.3MB and the images were 1252x1500 (1.2MB), 1031x1750 (1.2MB) and 1638x444 (330KB).

[Hitch]

Originally Posted by jhowell

I took a look at the List of Consuls in the free sample of the book you mentioned. From what I could see, Amazon is likely to be responsible for the image quality issues that you mentioned in that book. The original version provided by the publisher to Amazon used high quality images.

With Kindle books a lot depends on the device to which the book is being delivered and the format used. I looked at the sample in two different formats, KF8 (azw3) and KFX, both downloaded using Kindle for PC. I compared the total file size of the sample and the size and resolution of the JPEG images that make up the List of Consuls. The images in the KFX version were noticeably clearer with fewer artefacts and are likely closer to what the publisher originally provided.

The KF8 version was 1.4MB and the images were 932x1117 (126KB), 789x1340 (119KB), and 1638x444 (110KB).

The KFX version was 12.3MB and the images were 1252x1500 (1.2MB), 1031x1750 (1.2MB) and 1638x444 (330KB).

I had the sample delivered to my Fire10, figuring that that would give me the best view of the images, and they are all quite crisp there. I see no difference whatsoever between the full-page images on the Chronology or the list of consuls, versus the last page, even when zoomed. These are pretty good and undergo zooming--significant zooming--on my F10 without degradation.

I don't see poor quality here.

Hitch

[j.p.s]

Originally Posted by Hitch

Well, THAT was weird. I clicked your link, and suddenly, I was in YOUR Amazon account. You might want to modify that link. (I realized it after I noticed that the only "reader" available to me was the KCR, not my usual devices.)

Hitch

Well, that is certainly weird, but unless a moderator silently edited the URL to make it no longer do that, I don't see how that could have happened. Nonetheless, I have removed the URL and made a reference to the original posting in the bargain thread.

I also do not know what a KCR is but am pretty sure I don't have one. There are several e-ink kindles attached to my account.

[j.p.s]

Originally Posted by jhowell

I took a look at the List of Consuls in the free sample of the book you mentioned. From what I could see, Amazon is likely to be responsible for the image quality issues that you mentioned in that book. The original version provided by the publisher to Amazon used high quality images.

With Kindle books a lot depends on the device to which the book is being delivered and the format used. I looked at the sample in two different formats, KF8 (azw3) and KFX, both downloaded using Kindle for PC. I compared the total file size of the sample and the size and resolution of the JPEG images that make up the List of Consuls. The images in the KFX version were noticeably clearer with fewer artefacts and are likely closer to what the publisher originally provided.

The KF8 version was 1.4MB and the images were 932x1117 (126KB), 789x1340 (119KB), and 1638x444 (110KB).

The KFX version was 12.3MB and the images were 1252x1500 (1.2MB), 1031x1750 (1.2MB) and 1638x444 (330KB).

Originally Posted by Hitch

I had the sample delivered to my Fire10, figuring that that would give me the best view of the images, and they are all quite crisp there. I see no difference whatsoever between the full-page images on the Chronology or the list of consuls, versus the last page, even when zoomed. These are pretty good and undergo zooming--significant zooming--on my F10 without degradation.

I don't see poor quality here.

Hitch

Thanks! It's good news that publishers have started doing a better job.

I guess I need to start considering installing wine and getting kindle4pc.

The few times that I've accidentally got the KFX version on e-ink, the images had exactly the same dimensions as in the KF8 version but had significantly lower quality.