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PDF Technique 4, Test Process bullet 3 #4039
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I don't recall ever seeing an artifacted image displayed in Reflow view. Do you have an example of such a document or do you know the steps to cause it to happen? |
The attached PDF shows two blue boxes, both marked as artifacts when set to View> Reflow. This does not always happen but it definitely happens. This was created in Word. Acrobat continuous release 64-bit 2024.002.20991 |
I don't think the blue boxes are marked as artifacts. They are output by the screen reader and the PAC also shows them |
The blue boxes are marked as artifacts, but there's something wrong with them. If I un-artifact them and re-artifact them, they are not displayed in Reflow mode. The node Properties look exactly the same in both cases, so the difference is deeper in some place we can't see. How did you artifact them? Did you mark the boxes as decorative in Word? Some time ago I did some tests in PowerPoint that showed it treats boxes with coloured backgrounds differently from boxes with no background colour. I suspect the same happens with Word. As I (vaguely) recall, it was not necessary to mark the box with no background colour as decorative, but it was necessary to mark the one with the background colour as decorative, otherwise it got treated as an image. |
Actually, my last comment was not entirely true. In the original document, the four Path nodes are in a container that is shown as in the Contents panel. However, when you view the Properties, the Container Tag field is empty, which means it is not an artifact. By contrast, after un-artifacting and re-artifacting the container, the Container Tag field is correctly set to Artifact. So, I would say it's ok to retain the "Reflow the document and make sure the decorative image does not appear on the page" test. If containers are correctly artifacted, they will not be displayed. If they are displayed, it means they have not been artifacted correctly. |
Thanks for looking into this issue. |
You wouldn't expect a screen reader to announce the boxes because there is nothing to announce. They don't have alternate text and they are not images - they are Paths, which are just shapes. The behaviour of the empty Container Tag field is strange. This morning, when I created an artifact, the field showed "Artifact" and I could change it to something else. When I did exactly the same thing an hour later, the Container Tag field was greyed-out like you are seeing. A colleague verified this on another machine. But at least the boxes no longer appeared in Reflow mode. The joy of Acrobat! Testing Reflow is problematic because no user agents support Reflow fully. Most don't support it at all. There are a couple of options (maybe more) that give different results, including:
There are significant bugs in all the tools we use, including Word, Acrobat and PAC 2024. This makes life very difficult. Returning to your original question regarding Technique PDF4, I think the wording of the Reflow test in the Procedure section is adequate. If an item is not displayed in Reflow mode, it means it is correctly artifacted. This in turn means that there is no text alternative for the non-text content, which is what Technique PDF4 is all about. If an item is displayed in Reflow mode, it means it is either not artifacted or not artifacted correctly. Either way, the document needs to be fixed. The problem is actually in the previous test, which says "Using a PDF editor, make sure the decorative image is marked as an artifact." It seems that in Acrobat, there is no way to "make sure" the decorative image is correctly marked as an artifact. The Contents panel might show an item as being artifacted, but we have shown that it might not be artifacted correctly, so you can't rely on that. The Properties dialog should show the value of the Container Tag field, but it is usually empty and greyed-out even when an item is correctly artifacted, so you can't rely on that either. A more capable PDF editor might well display the Container Tag field correctly, but I don't know of one. |
https://www.w3.org/WAI/WCAG21/Techniques/pdf/PDF4
Reflow view does not consistently hide images marked/tagged as Artifact and should not be a test for this.
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