EPUB output - Page 30

bds4242 · 04-06-2009, 04:09 PM

Just used Calibre to convert an HTML book to epub to view in Stanza on my iPhone. All worked great. One issue: While the EPUB is properly broken up into chapters, I don't see any chapters in the list of chapters on the iPhone.

I'll try to explain better: When I'm in a section of the book in Stanza it says that it's an 'Untitled Chapter' consisting of (for example) 17 pages. When I get to the end of the section it loads the next chapter properly. The problem is when I click the little book icon to see my bookmarks and chapters, there are no chapters in the chapters section.

Is this a known issue or am I just doing something wrong?

Thanks,
Bill

kovidgoyal · 04-07-2009, 12:27 AM

If you open the book in calibre (click the view button) and then click the table of contents button in the viewer, does it show a list of chapters?

bds4242 · 04-07-2009, 02:25 AM

No.. that button is greyed out. Weird that Stanza seems to see the chapter breaks though, huh?

kovidgoyal · 04-07-2009, 11:48 AM

Ah well you need to have a Table of Contents. You will have to play with the automatic Table of Contents creation options to get it to work

pepak · 04-08-2009, 08:00 AM

What exactly does option --profile do? I kind of hoped it would optimize (resize, convert to grayscale) images to device's dimensions, but that's apparently not the case.

kovidgoyal · 04-08-2009, 11:05 AM

I am of the opinion that optimizing images for a device is not worth it, since it renders the ebook sub-optimal for future devices, for only a small gain. Of course for image centric publications like comics, calibre does optimize the images.

profile is used for making device specific changes to the EPUB without which the EPUB would not work on the device. The primary reason for this is that Adobe went and designed their own HTML rendering engine, which has a lot of quirks, so devices using ADE have quirky support for EPUB.

pepak · 04-08-2009, 12:05 PM

Quote:

Originally Posted by kovidgoyal

I am of the opinion that optimizing images for a device is not worth it, since it renders the ebook sub-optimal for future devices,

That's quite true, BUT: if I wanted to create an universal EPUB, I would not specify a profile, would I? I really do think that specifying profile is the one case where optimizing images is a good idea.

Quote:

The primary reason for this is that Adobe went and designed their own HTML rendering engine, which has a lot of quirks, so devices using ADE have quirky support for EPUB.

Which is one of the reasons why I need to optimize images - because I want to actually see them on my (quirky) reader...

kovidgoyal · 04-08-2009, 12:10 PM

Quote:

Originally Posted by pepak

Which is one of the reasons why I need to optimize images - because I want to actually see them on my (quirky) reader...

What reader is this? The 505? And its refusing to display images larger than the screen size? In my experience it rescales those images just fine.

pepak · 04-08-2009, 12:20 PM

I experience two behaviors with 505 and large images:

1) If the images are sufficiently large (e.g. 3100*5000), they are not displayed at all. That is, there is no image, but the reader takes a long time to render this "no image".

2) If the images are smaller but still large enough (e.g. 1100*1500), they are clipped, not resized.

kovidgoyal · 04-08-2009, 01:05 PM

OK if you can figure out threshold above which images are clipped, I'll add that to the SONY profile and have calibre resize images above that threshold.

pepak · 04-08-2009, 01:07 PM

Will do.

pepak · 04-09-2009, 09:47 AM

PRS-505, firmware build 18040.

test.htm:

Code:

<?xml version="1.0" encoding="windows-1250"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html; charset=windows-1250" />
<title>Test</title>
</head>

<body>
<div class="image"><img src="obr1.jpg" alt="" /></div><hr />
<div class="image"><img src="obr2.jpg" alt="" /></div><hr />
<div class="image"><img src="obr3.jpg" alt="" /></div><hr />
<div class="image"><img src="obr4.jpg" alt="" /></div><hr />
<div class="image"><img src="obr5.jpg" alt="" /></div><hr />
</body>
</html>

Images are 3144x4976 (obr1.jpg), 2000x3165, 1500x2373, 1000x1582 and 500x791 (obr5.jpg).

command line:

Code:

any2epub test.htm

The Reader exhibits a very interesting behavior indeed: It says the book has one page, but will happily go through all pages (while showing "1 of 1" in the status bar). But I don't expect Calibre to be able to do anything about that.

As far as rendering is concerned:

- Images 1, 2 and 3 are displayed as empty space approximately 170 pixels high
- Image 4 is displayed cropped to a section from (0, 0) (left, top) to approximately (570, 750) (right, bottom)
- Image 5 is cropped vertically also to about 750 pixels; horizontally, it fits

My conclusion:

1) Very large images are not displayed at all
2) Images larger than screen resolution of the Reader are cropped to fit, not stretched

I can, if you like, try to find the exact dimensions when a picture stops being shown, but considering #2, it seems pointless - if it is too large, it will get cropped (and become unusable) anyway. If the --profile=prs505 is used, the images that are larger than about 600x750 should be resized to this resolution while keeping aspect ratio. Smaller pictures should be left alone.

If possible, this behavior should be used for all pictures - embedded AND cover.

nrapallo · 04-09-2009, 11:03 AM

Quote:

Originally Posted by pepak

I can, if you like, try to find the exact dimensions when a picture stops being shown, but considering #2, it seems pointless - if it is too large, it will get cropped (and become unusable) anyway. If the --profile=prs505 is used, the images that are larger than about 600x750 should be resized to this resolution while keeping aspect ratio. Smaller pictures should be left alone.

If possible, this behavior should be used for all pictures - embedded AND cover.

For what it's worth, in PDFRead, I use 583x753 as the max. screen size for the Sony PRS-505. This was found to be optimal and anything larger (not too large

) got shrunk down to accomodate.

kovidgoyal · 04-09-2009, 11:45 AM

Quote:

Originally Posted by pepak

PRS-505, firmware build 18040.

test.htm:

Code:

<?xml version="1.0" encoding="windows-1250"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html; charset=windows-1250" />
<title>Test</title>
</head>

<body>
<div class="image"><img src="obr1.jpg" alt="" /></div><hr />
<div class="image"><img src="obr2.jpg" alt="" /></div><hr />
<div class="image"><img src="obr3.jpg" alt="" /></div><hr />
<div class="image"><img src="obr4.jpg" alt="" /></div><hr />
<div class="image"><img src="obr5.jpg" alt="" /></div><hr />
</body>
</html>

Images are 3144x4976 (obr1.jpg), 2000x3165, 1500x2373, 1000x1582 and 500x791 (obr5.jpg).

command line:

Code:

any2epub test.htm

The Reader exhibits a very interesting behavior indeed: It says the book has one page, but will happily go through all pages (while showing "1 of 1" in the status bar). But I don't expect Calibre to be able to do anything about that.

As far as rendering is concerned:

- Images 1, 2 and 3 are displayed as empty space approximately 170 pixels high
- Image 4 is displayed cropped to a section from (0, 0) (left, top) to approximately (570, 750) (right, bottom)
- Image 5 is cropped vertically also to about 750 pixels; horizontally, it fits

My conclusion:

1) Very large images are not displayed at all
2) Images larger than screen resolution of the Reader are cropped to fit, not stretched

I can, if you like, try to find the exact dimensions when a picture stops being shown, but considering #2, it seems pointless - if it is too large, it will get cropped (and become unusable) anyway. If the --profile=prs505 is used, the images that are larger than about 600x750 should be resized to this resolution while keeping aspect ratio. Smaller pictures should be left alone.

If possible, this behavior should be used for all pictures - embedded AND cover.

Sure, easy enough to do. Opena ticket with this information and I'll try to get it done for the next release.

wallcraft · 04-09-2009, 12:08 PM

Quote:

Originally Posted by kovidgoyal

What reader is this? The 505? And its refusing to display images larger than the screen size? In my experience it rescales those images just fine.

So far as I can tell, Adobe Digital Editions does not rescale images. As a test I used Baby-iLiad256.prc from More display issues on the DR, the attached version has been converting to ePub using Calibre. The MOBI version's images are rescaled to the window size when using MobiPocket's Desktop Reader. However, all the ePub version does in Windows Adobe Digital Editions and Sony eBook Library is crop the image to the screen size.

Does any ePub reader automatically rescale images? This seems to be yet another hole in the ePub specs.

04-09-2009, 09:47 AM	#447
pepak Guru Posts: 610 Karma: 4150 Join Date: Mar 2008 Device: Sony Reader PRS-T3, Kobo Libra H2O	PRS-505, firmware build 18040. test.htm: Code: <?xml version="1.0" encoding="windows-1250"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="content-type" content="text/html; charset=windows-1250" /> <title>Test</title> </head> <body> <div class="image"><img src="obr1.jpg" alt="" /></div><hr /> <div class="image"><img src="obr2.jpg" alt="" /></div><hr /> <div class="image"><img src="obr3.jpg" alt="" /></div><hr /> <div class="image"><img src="obr4.jpg" alt="" /></div><hr /> <div class="image"><img src="obr5.jpg" alt="" /></div><hr /> </body> </html> Images are 3144x4976 (obr1.jpg), 2000x3165, 1500x2373, 1000x1582 and 500x791 (obr5.jpg). command line: Code: any2epub test.htm The Reader exhibits a very interesting behavior indeed: It says the book has one page, but will happily go through all pages (while showing "1 of 1" in the status bar). But I don't expect Calibre to be able to do anything about that. As far as rendering is concerned: - Images 1, 2 and 3 are displayed as empty space approximately 170 pixels high - Image 4 is displayed cropped to a section from (0, 0) (left, top) to approximately (570, 750) (right, bottom) - Image 5 is cropped vertically also to about 750 pixels; horizontally, it fits My conclusion: 1) Very large images are not displayed at all 2) Images larger than screen resolution of the Reader are cropped to fit, not stretched I can, if you like, try to find the exact dimensions when a picture stops being shown, but considering #2, it seems pointless - if it is too large, it will get cropped (and become unusable) anyway. If the --profile=prs505 is used, the images that are larger than about 600x750 should be resized to this resolution while keeping aspect ratio. Smaller pictures should be left alone. If possible, this behavior should be used for all pictures - embedded AND cover.

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04-06-2009, 04:09 PM	#436
bds4242 Junior Member Posts: 6 Karma: 14 Join Date: Mar 2009 Device: Kindle 2	Just used Calibre to convert an HTML book to epub to view in Stanza on my iPhone. All worked great. One issue: While the EPUB is properly broken up into chapters, I don't see any chapters in the list of chapters on the iPhone. I'll try to explain better: When I'm in a section of the book in Stanza it says that it's an 'Untitled Chapter' consisting of (for example) 17 pages. When I get to the end of the section it loads the next chapter properly. The problem is when I click the little book icon to see my bookmarks and chapters, there are no chapters in the chapters section. Is this a known issue or am I just doing something wrong? Thanks, Bill

04-07-2009, 12:27 AM	#437
kovidgoyal creator of calibre Posts: 45,379 Karma: 27230406 Join Date: Oct 2006 Location: Mumbai, India Device: Various	If you open the book in calibre (click the view button) and then click the table of contents button in the viewer, does it show a list of chapters?

04-07-2009, 02:25 AM	#438
bds4242 Junior Member Posts: 6 Karma: 14 Join Date: Mar 2009 Device: Kindle 2	No.. that button is greyed out. Weird that Stanza seems to see the chapter breaks though, huh?

04-07-2009, 11:48 AM	#439
kovidgoyal creator of calibre Posts: 45,379 Karma: 27230406 Join Date: Oct 2006 Location: Mumbai, India Device: Various	Ah well you need to have a Table of Contents. You will have to play with the automatic Table of Contents creation options to get it to work

04-08-2009, 08:00 AM	#440
pepak Guru Posts: 610 Karma: 4150 Join Date: Mar 2008 Device: Sony Reader PRS-T3, Kobo Libra H2O	What exactly does option --profile do? I kind of hoped it would optimize (resize, convert to grayscale) images to device's dimensions, but that's apparently not the case.

04-08-2009, 11:05 AM	#441
kovidgoyal creator of calibre Posts: 45,379 Karma: 27230406 Join Date: Oct 2006 Location: Mumbai, India Device: Various	I am of the opinion that optimizing images for a device is not worth it, since it renders the ebook sub-optimal for future devices, for only a small gain. Of course for image centric publications like comics, calibre does optimize the images. profile is used for making device specific changes to the EPUB without which the EPUB would not work on the device. The primary reason for this is that Adobe went and designed their own HTML rendering engine, which has a lot of quirks, so devices using ADE have quirky support for EPUB.

04-08-2009, 12:20 PM	#444
pepak Guru Posts: 610 Karma: 4150 Join Date: Mar 2008 Device: Sony Reader PRS-T3, Kobo Libra H2O	I experience two behaviors with 505 and large images: 1) If the images are sufficiently large (e.g. 31005000), they are not displayed at all. That is, there is no image, but the reader takes a long time to render this "no image". 2) If the images are smaller but still large enough (e.g. 11001500), they are clipped, not resized.

04-08-2009, 01:05 PM	#445
kovidgoyal creator of calibre Posts: 45,379 Karma: 27230406 Join Date: Oct 2006 Location: Mumbai, India Device: Various	OK if you can figure out threshold above which images are clipped, I'll add that to the SONY profile and have calibre resize images above that threshold.

04-08-2009, 01:07 PM	#446
pepak Guru Posts: 610 Karma: 4150 Join Date: Mar 2008 Device: Sony Reader PRS-T3, Kobo Libra H2O	Will do.

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