odd epub image problem

[bobcdy]

I originally posted this on the epub forum, but because I constructed the epub with Sigil 3.1, and after further experimentation, I think the problem might have resulted from something awry with Sigil (?) I've changed the original post a bit and added new data on the problem that has led to my complete lack of understanding how to solve the problem:

I'm working on an epub with many png images, and it is essentially finished with final proofing complete. The problem occurs only when I upload the epub to my Bebook One (original version) and does not occur with either Sigil or Adobe DE on my computers. Most of the images are fine in the epub, but there are several no shows on the Bebook - that is, the space required to show the images is usually present, but the image is hidden. This occurs with two centered images each starting with <div class="center" or <p class="center"...or with two floating image each with <span class="floatleft" (or right)... All of the images are sized as percentages of the full width or height.

I originally thought the problem was caused by two images being very close to one another but this is not always true. To experiment, I replaced the "bad images" with others from the epub that show, but when replaced in the problem locations, the new images don't show either. Then with my computer Adobe DE, I opened the offending epub from the Bebook SD card - all the images show perfectly showing that the epub was not damaged by being copied to the sd card. Next I backed up all the material from the SD card, reformatted the card using sdformatter 2, copied the original epub from the computer to the card, ran it on my Bebook - had same problem. Thus, the problem does not result from a bad SD card.

The epub passes validation using the Threepress validator. Normally, when an epub runs on the computer ADE, it works perfectly on the Bebook; this is the first time I've had discrepancies.

I'm concerned about distributing the epub because the problem may not only be present with Bebook, but perhaps with other ereaders, and I only have one reader to test it with.

I've posted about this on the Bebook Company forum but haven't had any replies.

Does anyone have ANY ideas what could be wrong? How could I test further to determine the cause?

[theducks]

Originally Posted by bobcdy

I originally posted this on the epub forum, but because I constructed the epub with Sigil 3.1, and after further experimentation, I think the problem might have resulted from something awry with Sigil (?) I've changed the original post a bit and added new data on the problem that has led to my complete lack of understanding how to solve the problem:

I'm working on an epub with many png images, and it is essentially finished with final proofing complete. The problem occurs only when I upload the epub to my Bebook One (original version) and does not occur with either Sigil or Adobe DE on my computers. Most of the images are fine in the epub, but there are several no shows on the Bebook - that is, the space required to show the images is usually present, but the image is hidden. This occurs with two centered images each starting with <div class="center" or <p class="center"...or with two floating image each with <span class="floatleft" (or right)... All of the images are sized as percentages of the full width or height.

I originally thought the problem was caused by two images being very close to one another but this is not always true. To experiment, I replaced the "bad images" with others from the epub that show, but when replaced in the problem locations, the new images don't show either. Then with my computer Adobe DE, I opened the offending epub from the Bebook SD card - all the images show perfectly showing that the epub was not damaged by being copied to the sd card. Next I backed up all the material from the SD card, reformatted the card using sdformatter 2, copied the original epub from the computer to the card, ran it on my Bebook - had same problem. Thus, the problem does not result from a bad SD card.

The epub passes validation using the Threepress validator. Normally, when an epub runs on the computer ADE, it works perfectly on the Bebook; this is the first time I've had discrepancies.

I'm concerned about distributing the epub because the problem may not only be present with Bebook, but perhaps with other ereaders, and I only have one reader to test it with.

I've posted about this on the Bebook Company forum but haven't had any replies.

Does anyone have ANY ideas what could be wrong? How could I test further to determine the cause?

I have a Astak Pocket Pro (same HW as the Mini) and the code share lots of common traits

ADE on the PEz does not behave (with images) the same as on the PC.
Another thing I found was the PEz ignores SOME parts of the stylesheet if I place comments

/* this is a comment */

in the wrong, (unknown ) place. (I was centering a JPG at chapter starts. Failed on the PEz until I removed the comments preceding the class in the stylesheet)

Sigil, ADE PC, EPubreader have no problem.
EPUB validates with Flightcrew

[bobcdy]

Thanks for the suggestion, theducks,
I deleted the two comment lines in my style sheet but that didn't help either. I may end up buying another ereader to check the epub, for example the Sony PRS 950 looks good at bestbuy, because I'd like a touch screen reader anyway. I've spent weeks working on the epub, almost full-time, and hate to scrap it if the image no-shows is exclusively a bebook problem.
Bob

[bobcdy]

I thought I had the answer: even though Threepress found no errors, Flightcrew found that I hadn't used some images that I had added to the epub. I removed those unneeded images, saved, and checked again with FC - no problems. Great Hopes at that point, but after sending file to bebook there are still the same no-show images, that are definitely in the unzipped manifest and in the Images subdir. I've exhausted my abilities to troubleshoot the problem.

[Jellby]

Originally Posted by bobcdy

All of the images are sized as percentages of the full width or height.

Using a percentage in height might not work as you expect. If the image is inside an element with no fixed height (typically a <p> or <div> inside <body>), the percentage may actually refer the the width of the container (typically the page or screen).

The above is probably unrelated to your problem, which looks like a bug, but I guessed you'd like to know it.

[Perkin]

I know some readers have problems with centering elements.
If the images are same % width, you could try this workaround.
(Or if several different %'s you need several classes for the different %'s)

In the class instead of doing a text-align:center; change it to margin-left:#%; the # being (100-width%)/2 e.g. if width is 60% then it would be (100-60)/2=20 -> margin-left:20%;

If it works, you could create several classes to compensate for several % widths

pic10 {margin-left:45%}
pic20 {margin-left:40%}
pic30 {margin-left:35%}
pic40 {margin-left:30%}
pic50 {margin-left:25%}
pic60 {margin-left:20%}
pic70 {margin-left:15%}
pic80 {margin-left:10%}
pic90 {margin-left:5%}
pic100 {margin-left:0%}

Then use the correct selector for the element holding the picture.

[bobcdy]

Perkins,
Thanks for the input. The problem doesn't seem to be with centering images - never had a problem before with my other epubs, and with this epub the problem is consistency. Why should most of the images show and are centered perfectly, but a few don't show at all?

[Perkin]

What I was thinking is that some eReaders can't center properly, so I was thinking that they may have been displaying them, but off left or right page margin, so you weren't seeing them.

Just curious, if you don't center them , just leave them as normal, do they still not display?

I know also some ereaders have problems with some image widths, but as you said you substituted other pics for them, and they still didn't display I don't think that this would be a problem, unless you still had the same width settings.

[bobcdy]

Thanks Perkin and Jellby,
I tried everything suggested and more: no centering, new images with different names, adding extra blank paragraphs between offending images, etc. etc, etc. Also found that if I move the offending image to another location, such as at the end of the chapter, it still does not show. It's as though there is some switch that says "hidden" for the image, but I have no such tags, and the images are all prepared the same way from tif images using Photoshop CS3. Also tried replacing the ENTIRE css stylesheet from another epub with similar image features - still had the problem, although the rest of epub looked odd because of other formatting differences between the problem epub and the other one's style sheet.

The no show images are the most peculiar sort of error I've ever encountered, and I don't see any solution because I don't even have even a vague understanding of the cause. I even purchased a new Sony PRS 950 (I was planning to get a touch screen reader for months), but the problem persists on the 950 so it's not just a bebook problem; but the images show perfectly with Adobe DE on two different computers (????)

What possible sources could cause this error?

[Hitch]

I have a really dumb question: are the images RGB or CMYK? I had a problem with an image not showing up that turned out, through inattention, to have been saved as a CMYK, not RGB...and it might as well have been the invisible man. Dunno if that will help--I am NOT an image maven, by any stretch, it's my weakest area--but thought I'd mention it just in case.

HTH,

Hitch

[Perkin]

Can you upload a small epub, containing just one/two pics that (don't) show the problem, then we can see if we can pin the problem down.

[Perkin]

I created an epub with 3 images, one jpg and two tifs,(one RGB and one CYMK), neither of the tif images displayed on my reader (sony prs-300).

One thing I noticed was that the tifs were a lot bigger in size than the jpg, (they were cover Images 333x500 pixels). So it could be something to do with that as well.

Would it be possible to convert a couple of your tifs that don't display into jpeg/png and try them in an epub (making necessary code changes).

Do you NEED to keep the tif format, as if you convert to jpg/png the filesizes will be a LOT less, and depending on your reader wont display much difference in quality anyway.

[Hitch]

Originally Posted by Perkin

I created an epub with 3 images, one jpg and two tifs,(one RGB and one CYMK), neither of the tif images displayed on my reader (sony prs-300).

One thing I noticed was that the tifs were a lot bigger in size than the jpg, (they were cover Images 333x500 pixels). So it could be something to do with that as well.

Would it be possible to convert a couple of your tifs that don't display into jpeg/png and try them in an epub (making necessary code changes).

Do you NEED to keep the tif format, as if you convert to jpg/png the filesizes will be a LOT less, and depending on your reader wont display much difference in quality anyway.

Yup, I'm with the Zealot, over there. I suspect that the tifs are part of the problem. FWIW.

Hitch

[Jellby]

I think bobcdy said he had created the images from tiffs, not that they were tiffs. The tiff format is not supported by the ePUB spec, so they are not guaranteed to work (they are almost guaranteed not to work, actually).

[bobcdy]

Yep, they were png files; I did find the problem: I was looking for something complex and wasted 3 days exploring all these avenues, when the simple truth was that I had forgotten to correctly size the images. I started with a 600 dpi pdf page, converted it to gray-scale tif, cut out the image from the text, and saved the image as the master tif file. Then I changed the resolution to 150 dpi and saved it as png for the epub, but forgot for those two images (although I did ok with the other 47) to also reduce the dimensions in inches to a value that an ereader could use - duh!

At least I'm happy with the Sony PRS-950 with the neat touch screen, etc. etc. - my only gripe is the lack of user changeable battery.
Bob