Conversion of Images from HTML Files

[Gretsch]

I have been trying to convert a PDF book with hardly any text into an EPUB and MOBI format. I converted all of the PDF pages as high-quality JPEGs.

I inserted the JPEGs into a Word File and saved as a Filtered HTML page, which I have done before with another book with excellent results. This time, however, a lot of the images became blurry.

I went back and saved them as PNGs and TIFFs. These looked very clear in Word but improved only slight after converting them using Calibre. (i.e. still not significant enough to release to the public)

Has anyone any suggestions as to what I can try next?

Thank you,
SG

[eschwartz]

Originally Posted by Gretsch

I have been trying to convert a PDF book with hardly any text into an EPUB and MOBI format. I converted all of the PDF pages as high-quality JPEGs.

I inserted the JPEGs into a Word File and saved as a Filtered HTML page, which I have done before with another book with excellent results. This time, however, a lot of the images became blurry.

I went back and saved them as PNGs and TIFFs. These looked very clear in Word but improved only slight after converting them using Calibre. (i.e. still not significant enough to release to the public)

Has anyone any suggestions as to what I can try next?

Thank you,
SG

Try inserting the images manually into the epub? You can use calibre's Unpack Book, shortcut key is "U", and overwrite the images, or use "T" to edit the book with a nice GUI.

I'm sure there is some setting or another that can preserve the image quality within Word, but I have no idea what -- it's not my area of expertise.

(But Hitch will probably come along soon, and she does this for a living, so I bet she knows.)

[Gretsch]

Thank you for the suggestion. I'll give that approach a try!

[BetterRed]

If you have Word 2007/10/13 try saving as DOCX and get calibre to convert that.

I just dropped a couple of images into word, saved to docx, and converted to epub - the attachment shows the results- word shrank the images to fit on an A4 page, calibre shrank the images to fit on the Default Output Profile

If I increase the page size in word I get less shrinkage (none if its big enough), and if I use Tablet as output profile I get no shrinkage in the calibre convert.

But even with the shrinkage by word and calibre the quality was OK but if I was to shrink those images down to fit on a 5" ereader I reckon I'd see some jagged edges.

BR

[cybmole]

how is all this better than just sending the pdf to the e-reader ?
kindles can handle pdf so tick off .mobi conversion.

most epub based readers also do PDF OK so tick off epub....

[eschwartz]

Originally Posted by cybmole

how is all this better than just sending the pdf to the e-reader ?
kindles can handle pdf so tick off .mobi conversion.

most epub based readers also do PDF OK so tick off epub....

Because PDF is a horrible format that is barely supported -- sure, it will render, but it will look horrible on a 6" screen.

[BetterRed]

Originally Posted by eschwartz

Because PDF is... is barely supported

crap, there are far more things published in PDF that all the other formats combined - except maybe paper.

Governments, think tanks, universities, quangos, consultancies... issue a more publications that all the 'book publishers' combined - and the majority of them are in PDF.

Then of course there's magazines and journals - where again PDF is the dominant format

BR

[eschwartz]

Originally Posted by BetterRed

crap, there are far more things published in PDF that all the other formats combined - except maybe paper.

Governments, think tanks, universities, quangos, consultancies... issue a more publications that all the 'book publishers' combined - and the majority of them are in PDF.

Then of course there's magazines and journals - where again PDF is the dominant format

BR

And here I thought the topic was PDF and ereaders... silly me...

Okay, well, I should've specified.

[Gretsch]

Since it is already in PDF format, as specified by the printing company for the hardcopies, I would have loved to be able to go from PDF to EPUB. Unfortunately, the results were awful, as so many have already attested.

[BetterRed]

Originally Posted by Gretsch

Since it is already in PDF format, as specified by the printing company for the hardcopies, I would have loved to be able to go from PDF to EPUB. Unfortunately, the results were awful, as so many have already attested.

My ex had similar problem, her book had lots of embedded pictures and graphics. I couldn't get a decent EPUB even from from the original Word file. It also had a couple of multipage colour plate inserts.

I told her to get a quote from http://www.booknook.biz/ (Hitch) - not sure if she has, too busy writing Volume 2 I suspect.

BR

[Gretsch]

Tried inserting the images by dropping them in the EPUB via Calibre: the same issue occurred with the images blurring. I also tried to convert from a DOCX file, but Calibre ignored all images and converted only the text.

Seems that the actual compression used in the conversion process is what I need to figure out how to work around. Even with the highest quality and DPI images, the compression is too much for the images to possess an acceptable clarity.

I appreciate the suggestions using the other approaches!

[BetterRed]

Originally Posted by Gretsch

Tried inserting the images by dropping them in the EPUB via Calibre: the same issue occurred with the images blurring. I also tried to convert from a DOCX file, but Calibre ignored all images and converted only the text.

Seems that the actual compression used in the conversion process is what I need to figure out how to work around. Even with the highest quality and DPI images, the compression is too much for the images to possess an acceptable clarity.

I appreciate the suggestions using the other approaches!

Hmmm, I don't understand - Attached zip has

• original image of a bear - 6.3MB 4256x2832 jpg,
• images from word and epub files (same because I used 'tablet')
• a docx, I drag dropped the image onto document, it got resized
• an epub converted from the docx with Tablet as the output profile (no resize)

I don't have an ereader as such here, but in the calibre ebook-viewer program the epub looks pretty OK to me, same on my Galaxy Note - what do others think - Gretsch especially

I think there's a way to insert an image into a DOCX so that it retains its dimensions etc - but I don't know how to do that.

BR

[cybmole]

Originally Posted by BetterRed

crap, there are far more things published in PDF that all the other formats combined - except maybe paper.

Governments, think tanks, universities, quangos, consultancies... issue a more publications that all the 'book publishers' combined - and the majority of them are in PDF.

Then of course there's magazines and journals - where again PDF is the dominant format

BR

which is ONE reason why e-readers have native support for PDF format , with helpful tools to zoom, flip orientation etc.

I don't get how all your complex image processing is ever going to lead to a better display than the original pdf file, (on he same e-reader screen). unless you OCR all the text & make it reflowable. you can't add clarity that does not exist to begin with- your image can only ever be as-good-as the source, not better.

@eshwartz "Because PDF is a horrible format that is barely supported -- sure, it will render, but it will look horrible on a 6" screen." But a compressed picture of a PDF page will look even worse, so the OP's approach is deeply flawed

[Gretsch]

Perhaps, it is a matter of time when you can set images preferences in Calibre. I am just surprised this issue has not come up before with graphic magazines/books and the like.

[BetterRed]

Originally Posted by Gretsch

Perhaps, it is a matter of time when you can set images preferences in Calibre. I am just surprised this issue has not come up before with graphic magazines/books and the like.

@Gretsch - can you post a sample of the problems you get (as I did in my previous post) and tell us how you're looking at the EPUB you have been able create - the calibre viewer, on an ereader, on a phone etc.

And what sort of book are we talking about - if its a 'coffee table' style book full of HQ images, then I for one wouldn't know where to start, or if conversion is even feasible

BR