How to know the total pixels of an Image in Indesign

[arvindkumarg]

Hi,

I have got a rejection from apple which says the image should not be images larger than 4,000,000 pixels in the ePub file.

I have around 500 images wherein it is taking too much time to manually multiply the image dimensions and get the total pixels of the image.

Is there any Script or batch method in Indesign or any other software where we can get to know if the image exceeds 4,000,000 pixels.

It would be great if there is a quick method to solve this issue.

Regards

Arvind

[Willi Adelberger]

Go to the linked files and look for some Information on the linked files. But this Image seems to be quite large. I don't believe you imported it onpurpose for an epub. What do you want to afford with such an Image?

[Derek Cross]

You could also set up preflight to note images above a certain size.

[arvindkumarg]

Hi Derek,

Thanks for the reply.

Can you please help me with the Preflight settings.

Regards

Arvind

[DaveJCummings]

exactly Derek.  I design a lot of ads in InDesign and I have preflight set up for that, for both newsprint as well as glossy print, since both of those have different parameters. Just like I use ink levels alot in separations preview to make sure things are not going to go over certain thresholds for print (220 for newsprint, 300 for glossy)

[rob day]

Preflight checks for a ppi resolution threshold, but I don't see away to check for pixel dimensions, which is what the OP is after. The OP can't have an image that's over 2000px x 2000px (4,000,000 pixels). A 2000x2000 pixel image could have any ppi resolution depending on its output dimensions in inches.

[DaveJCummings]

That would be in the links window after you place the image.   You can have that set up for that.   Now my preflight I do have that set up to alert me if things were past a certain size,  but that's a preflight set up provided to me by my employer

[rob day]

Yes the Links panel gives an images's pixel dimension, but Preflight doesn't.

Preflight's IMAGES and OBJECTS>Image Resolution lets you set a threshold for ppi, but that wouldn't help with pixel dimensions. A 2000x2000 pixel image could be10ppi with an output dimension of 200"x200", or it could be 2000ppi with an output dimension of 1"x1"

It would be possible to script — scripting lets you get an image's width and height in inches, and its Effective resolution.

[arvindkumarg]

Hi Willi,

Thanks for the reply.

We have used it for the print as well as the same image for ePub.

Its a screenshot that we have and the Dimension is 3840 x 2336 = 8970240.

If we reduce the dimensions to bring down to 4,000,000 pixels the image quality is lost. So we have used the same size screen shot for both Print and digital version.

Regards

Arvind

[Jongware]

If your image must be this large, then you have to contact Apple. It sounds like your document in InDesign is correct and so it's their problem, not Adobe's.

[rob day]

Its a screenshot that we have and the Dimension is 3840 x 2336 = 8970240.

If we reduce the dimensions to bring down to 4,000,000 pixels the image quality is lost. So we have used the same size screen shot for both Print and digital version.

The reason for the epub limit is the image will eventually have to be sampled down when it is displayed in the epub (xhtml). It is very unlikely the epub will ever be viewed on a device that is capable of displaying a 3840 wide image—the current 13" iPad Pro has a native pixel dimension of 2732 x 2048. So even if your 3840 pixel image happens to be displayed as full screen on an iPad Pro it has too much resolution.

Print is different, it can handle much more resolution—for print InDesign resizes rather than resamples, so it is possible to output the full effective resolution with no sampling.

[arvindkumarg]

Thanks for the reply Rob.

So you mean to say I have that I will have to use the high res image for the print and then resize it according to the specifications for the ePub and relink to the Indesign file.

Also I possible can you please help me with the tool, Preflight or a Script which can show me the total size of the images, so that it can be worked on.

I have lots of images to be processed.

Waiting for your reply.

Thanks

Arvind

[rob day]

What are you delivering to Apple for the ePub creation? Not an InDesign file right?

[arvindkumarg]

No we are not giving the Indesign file.

We have given them the ePub

[Frans v.d. Geest]

I have had the same, many times. I use Unzip/zip ePub or Cancrusher to unzip the file, then find large images in the image folder of the unzipped ePub. Open those from that folder and change the resolution (lower), save the image back into that same folder and then use one of the apps to zip to ePub again.

For some reason InDesign does NOT resample all images down even if told to do so in the export options.

I have to do the unzip/zip/change resoltion all the time for our ePubs...

[arvindkumarg]

Thanks for the reply Frans

[rob day]

I'm not seeing a problem when I place a .PSD. The exported pixel dimension seems to be correct relative to the page’s inch dimensions.

Here my page dimension is 11" x 8.5" and I'm setting the Resolution to 72ppi

I'm expecting the exported image width to be 792px (11x72=792), which is what I get.

If I set the Resolution to 300ppi I get a 3300px width, so to stay under 4,000,000 I can't use 300ppi when there are full bleed images on an 8.5"x11" page:

 

[Dave Creamer of IDEAS]

An easy way to process the images is with Zevrix LinkOptimizer. Not exactly cheap, but it depends on how many EPUBs you create.

Optimize Adobe InDesign link size, resolution, color and format | LinkOptimizer

Another option is to use Photoshop's Image Processor to a new folder with the same file names, then in InDesign, relink to the new folder. Make the EPUB and then link the images back to the original folder.

[rob day]

An easy way to process the images is with Zevrix LinkOptimizer. Not exactly cheap, but it depends on how many EPUBs you create.

But isn't the plugin optimizing the images' output resolutions as pixels per inch, and not their pixel dimensions? HTML doesn't have an output resolution ppi property.

In my #17 example the placed image's Effective resolution is 427ppi. If the image was optimized to 300ppi, its pixel dimensions would still be 3300 x 2547 (more than the Apple store's 4,000,000 total pixel limit). On the epub export I would have to choose something less than 300ppi from the Conversion tabs Resolution drop down (which only has 4 options) in order to get below 4,000,000 pixels. I don't think there is a way to turn off down sampling on an epub export.

It would be futile to try and control an image's exact pixel dimensions in the epub, because its final displayed pixel dimensions would depend on the client device’s display size and its orientation.