Educating the Confused – Muscatine and AP JPEGS

This time it is NBC who has to take the education…

Yes, I had noticed the 5.6Mb size of the Muscatine file but I had tried and been unable to extract any more information that a 72×72 Pixel Height: 1,243
Pixel Width: 1,043 jpeg…

None of my tools appear to be able to touch the largest of these objects.

Object 13

/Subtype /Image
 /Length 5550950
 /Filter /FlateDecode
 /Name /X
 /BitsPerComponent 8
 /ColorSpace 15 0 R
 /Width 1739
 /Columns 1739
 /Predictor 2
 /BitsPerComponent 8
 /Colors 3
 /Height 2071

Now I want to have a look at the file…  Somehow none of the stream decoders like the Object. This is darn annoying as I want to see this image… 3 colors… 8 bits per component 1739×2071 what the heck is it… It is too small to be a regular TIFF. The JPEG I found had dimensions 1043 × 1243 @72 DPI. Ah I see, the conversion is 0.6 suggesting a 120 DPI document. Hmm better than 72 DPI but still lower than the 200 DPI for the JPEG in the AP document.

Hermitian: The TIFF image data from the image info panel in Photoshop CC is: W = 8.695 in. ; H = 10.355 in.

Yes that would make it 200 by 200 so why the 120 DPI document? What am I looking at there?

Hermitian: So maybe you could explain how the Muscatine PDF image was created by reducing the page-size of the AP PDF down to the size of the Muscatine PDF without increasing the pixel resolution of the scaled AP PDF above 200 PPI x 200 PPI?

Let’s walk through this

AP JPEG 13.49 × 16.17 inches

DPI Height: 200
DPI Width: 200
Pixel Height: 3,234
Pixel Width: 2,698

Muscatine TIFF 8.695 x 10.355 inches

Pixel Height: 2071
Pixel Width: 1739

Yes, that computes quite nicely 2071/10.335=200  1739/8.695=200. Both are 200 DPI just one contains more pixels because of the larger canvas size. The JPEG I found embedded has dimension 1243×1043, let’s see… that’s about 120 DPI (1243/10.335= 120.17, 1042/8.695=120). It all starts adding up.

Glad to be of help Hermitian, that was not that hard. You may want to look more closely at the image conversion plugin perhaps? But the numbers line up quite nicely. The size of the canvas was changed while maintaining the same PPI.

And before you state that this cannot be done, read this

The Resample Image option lets you change the size of an image without changing the resolution. If you need to print at a specific resolution, or at a smaller or larger resolution than the current image allows, resample the image. However, resampling can degrade image quality.

Just like in GIMP…

I now found the object..It is a CompositeImage object embedded inside private data for Adobe Photoshop. In other words, it contains likely the PSD file… What a horrible workflow but yes Hermitian was right.

Ironically this references the image which was last modified around 10AM EDT

/Private 12 0 R
/LastModified “(D:20110427090136-06’00’)”

The file was uploaded April 27, 2011 9:16 am which means 10:16EDT

All still adds up. So why the metadata that suggest 9:00EDT? I venture to guess that it imported the JPEG sent by Applewhite at 8:53 and it was picked up by Muscatine Journal.

As to the workflow, when saving to PDF, the Preserve Photoshop Editing Capabilities-button was hit which embeds a PSD in a PDF.

When you open an image in Photoshop, Photoshop  converts it into a PSD file so that you can edit the file. After all it is hard to impossible to edit JPEG files directly.

So when you save as PDF and tap the wrong button the PSD is saved as well.

As to the TIFF formatted image, perhaps Hermitian can explain what he sees when he does a high zoom comparison with the AP photograph?

Ah, the 8 bits per component may be a give-away. When you take a jpeg which has only 8 bits depth, it will convert to an 8-bit TIFF.

I believe we have a likely workflow here.

3 thoughts on “Educating the Confused – Muscatine and AP JPEGS

  1. The final nail

    EXIF stands for “Exchangeable Image File Format”. This type of information is formatted according to the TIFF specification, and may be found in JPG, TIFF, PNG, JP2, PGF, MIFF, HDP, PSP and XCF images, as well as many TIFF-based RAW images, and even some AVI and MOV videos.


    So TIFF can be found in many images, including JPG.. The PSD file contains an internal format not TIFF. What you are seeing is just an interpretation of the JPEG it imported.

    See for instance this jpeg

  2. JFIF is the tag in the AP document that contains the 200×200 information but JFIF is disfavored by Adobe

    The JFIF standard has been largely abandoned; most importantly, all modern digital cameras follow Exif. Both JFIF and Exif specify a particular APPn marker segment as immediately following the SOI marker. Neither of the JFIF and Exif specifications references the other, so there is no declared standard for mixing them.

    Tiff:Xresoliution and Tiff:Yresolution tags are the most logical ones to store this information.

    Yes, this is starting to look good, now let’s see if we can find some additional evidence… Simple logic and reason and the realization that the PSD file stores a native, internal format only.

    So I predict that if you create a TIFF file out of it, and compare it to the AP JPEG, it will be similar except for the color mess introduced by trying to remove the bluish tint.

    PS: Hermitian has never explained why Applewhite would create a document with such an obvious color imbalance….

  3. I missed something obvious… pdfimages can also extract ppm formatted images and when imported into GIMP it shows a 1738×2071 200 DPI image, clearly of lower quality (visible) than the AP document as the colors appear more ‘smeared’. I’d say another ‘mystery’ resolved.

Comments are closed.