JPEG2000 is slow to load in acrobat

Report · Jun 23, 2022

I add and Save to a ~ 9 x 4 inch page, identical 1200 ppi images of ~ 4 x 3inches, in various formats of original image file sizes:

TIFF: 88.1 MB

PNG: 24.6 MB

JP2: 5.7 MB

The JPEG2000 gives best visual impression; is preferred choice.

When the document is opened, 'response time' is:

TIFF: essentially instant

PNG: essentially instant

JP2: approx. 4-5 seconds

The JPEG2000 format is new to me. I am impressed with result, apart from load time.

1. Is there an Acrobat setting that speaks to JP2 performance in a doc, how it loads, etc.?

2. I am aware of 'pyramids' [Quality layers?] in JP2 decoding/presentation. Perhaps an approach is to insure that the 'initial load' of the JP2 is distinctly restricted to lo-res, and image quality 'fills in' and improves to max-res during that 4-5 secs., but initial appearance is instantaneous. So far, I've been unable to address this by processing the image in QGIS [also new to me].

The slow load is unsurprising in this respect: When I view the JP2 image in Apple Preview, it's reported size is ~ 68 x 62 in. At 72 ppi. That's a lot for Acrobat to handle, when smushing it down, converting ppi, etc. I have a vague understanding that some apps display a JP2 only at a default 72 ppi. In QGIS I've set the image parameters to dimensions ~ 4 x 3 in., at 1200 ppi [exactly as the TIFF and the PNG], and Exported. However, MacOS and Preview still treat it as 72 ppi. I'd love for Acrobat to promptly load it at 72 ppi, then 'work its way up' to 1200 ppi.

Curious note: When I select the image in Acrobat, for Edit Using > Preview, the image dimensions are the expected ~ 4 x 3, AND the ppi 2400. However, Export from Preview always yields a stubborn 72 ppi.

I can upload samples, but am aiming first to better understand JP2 in Acrobat. [I'm pretty sharp with GIMP; it can't handle JP2. I've not Photoshop to work with.]

There's something fishy about taking 4 seconds to display a 5.7 MB image.

Report · Jun 23, 2022

JPEG2 is a brilliant idea that never caught on. Nothing has been touched in probably 15 years, and nobody is now likely to ever do the work to optimize it further. How specifically do you add these images with Acrobat? Generally, I'd expect the smallest image to take the longest time to display, and this is an large image, very well compressed: 4 x 3 inches at 1200 ppi is 4800 x 3600, or 17 megabytes -- but something is strange since you say that a single PDF derived from TIFF is 88MB??

Report · Jun 23, 2022

Wait, my mistake. An RGB image 4 x 3 inches at 1200 ppi is 17 x 3 megabytes = 51 MB. Still doesn't explain how your TIFF-derived file can be 88MB.

Report · Jun 23, 2022

Well hello, Test –

I am delighted to see your reply here! I have written in the past [re some particularly nettlesome topic to which you'd replied, and recognizing it was you, and knowing you held a certain firm opinion], "I quaked when I saw the giant green tire rearing up at me." You know, I rely on this forum, and it's not uncommon that I come across a helpful post of yours, sometimes dating back to 2014 [or perhaps '09?].

Let me divide this; four parts – clarification on my materials, online location of reference materials, comments on JP2 image format, and personal findings so far.

1. How do I add these images? The usual suspects:

Acrobat, Edit PDF > Add Image > {filename on OS}
From OS, 'Open With' Acrobat [default Acrobat quality settings, e.g. 'Medium', in this instance]
Preview, Export as PDF
QGIS, Export > PDF

File Sizes: The three file sizes I listed are for original source image. In each case, upon conversion to PDF, substantially smaller [except JP2; unaltered]. So it is not at all a case of "a single PDF derived from TIFF is 88MB". It is 88 MB TIFF to a PDF.

So it's:

TIFF: 88.1 MB => 1.6 MB PDF

PNG: 24.6 MB => 1.6 MB PDF

JP2: 5.7 MB => 5.7 MB PDF

– – –

2. Here are references:

Forum - Envelope, BR to Starr - pushed - WITH BUGS Crop to Whole Stamp 4930 x 4457.tiff

Forum - Envelope, BR to Starr - pushed - WITH BUGS Crop to Whole Stamp 4930 x 4457.png

Forum - Envelope, BR to Starr - pushed - WITH BUGS Crop to Whole Stamp 4930 x 4457.jp2.zip

[Case partially to your point – the server won't convey a .jp2 directly; this one must be downloaded, 'containerized', to you.]

Forum - Envelope, BR to Starr - pushed - WITH BUGS Crop to Whole Stamp 4930 x 4457 TIFF 'Open With' ...

Forum - Envelope, BR to Starr - pushed - WITH BUGS Crop to Whole Stamp 4930 x 4457 PNG 'Open With' A...

Forum - Envelope, BR to Starr - pushed - WITH BUGS Crop to Whole Stamp 4930 x 4457 JP2 'Open With' A...

In my final publication, rather than this ~ 4 x 3 inches, the image [or rather, the 'solid paper' portion of it] is scaled down to precisely the official USPS .87 x .979 inches.

A subject of interest is seen in these samples at cursor coordinates 2.89, 1.14 inch [different in the JP2].

In final publication, the JP2 gets scaled down by this procedure: After a PNG placeholder is first precisely situated, then Acrobat, Replace Image > JP2.

I should note that the load time of the JP2 is the same, regardless whether it's 68.47", or .87" wide.

– – –

3. When is the year JPEG2000 ahead of the year TIFF 2022?

Like you, I'd been dismissive and derisive and suspicious of JPEG2000. First of all, too many characters to type. Secondly, I dismissed it as outdated, thinking of it along the lines of Acrobat, "Export To > Microsoft Word > Word 97-2003 Document".

I recently discovered how naive was I, and just plain uninformed, and wrong. There are two notable JP2 drawbacks – lack of browser support [at present, only Safari], but doesn't impact my work – and lack of backward compatibility.

Otherwise, it's become a mainstay, from Library of Congress and other archivists, to medical imaging, to a wide swath of science and engineering interests. Perhaps the greatest testimony is its adoption as the native resolution for satellite imagery, going forward [e.g. the 'Sentinel 2' pair of orbiters, operated by European Space Agency].

I recommend two summaries:

In case you wondered if JPEG 2000 is still in use, the answer is a resounding yes. and

Bitrate control and quality layers in JPEG2000

– – –

4. Personal Findings:

From an artist's perspective, transparency is essential to image presentation. You see it here [though not evident in the above PDFs on white page].

Efficiency of the format allows greater detail and clarity to be presented, for a given file size.

The higher dynamic range allows a richer, more lush, representation. And this example is not even executed at 'lossless' settings.

The greatest benfit in the context of the task at hand, is performance, substantially benefitting the operator of the document. The story told in the document requires use of extreme magnification by the user. There is no hindrance of the TIFF or PNG being severely scaled down to fit into the postage stamp. The image has a 'native' width of roughly 34 inches, so that entails cramming its ~1,000 square-inches into the ~1 square-inch stamp. No downside in that, per se. However, the user must view well inside the stamp edges. When this is done, smoothly 'moving about' is hampered. Whether sliding the Acrobat Window Controls, or dragging the image within a fixed window, the TIFF and PNG exhibit notable lag. Worst of all, in the effort to 'keep up', the image 'tears'/rips during its refreshment to a new position. By contrast, JP2 view transitions are fluid. These examples don't fully convey it – in the final document, with the 1" stamp on a 9" page, with the zoom necessarily at 6400%, the difference is clearly evident.

All would be ideal if the image opened promptly, at lo-res, then took its time for 4 seconds, to sharpen up.

– – –

Say, Test, while I have your attention, if you've thoughts on management of re-sizing viewer windows, have a look at my query, and a linked f'rinstance, at this topic.

Cheers,

BR