What is the relationship between navPoint navLabel and navPoint content

When playing back a Z386 format book should the content pointed to by the navPoint content sub-element be rendered in preference to the navPoint navLabel sub-element? Should the former be rendered for local navigation and the latter for global navigation or are they required to be the same?

Hello Nick, does this help?: navPoint The navPoint element contains one or more navLabels, representing the referenced part of the document, e.g. chapter title or section number, along with a pointer to content. navPoint's may be nested to represent the hierarchical structure of a document. and navLabel Description: Contains a label identifying a given navMap , navPoint , pageList, pageTarget, navList, or navTarget in various media for presentation to the user. When applied to navPoint's, it generally contains the heading of the referenced section of the document. Can be repeated so labels can be provided in multiple languages. as found in: http://www.niso.org/workrooms/daisy/Z39-86-2005.html#NCXElem rgds Olaf

Thanks for your reply. I'm still confused. So the content element of a navPoint does not necessarily point to a smil time container which also renders the name of the heading but possibly renders the first piece of text under that heading? For example: a navPoint with navLabel "introduction" does not have to point to a smil element that renders "introduction". If it must, when should the player use the navLabel rather than the content? If not, should the player refer to the navLabel when moving to the next or previous phrase? When might I provide alternate languages for navPoints? This seems to indicate that I can provide heading in languages other than the one used in the book.

Hi Nick, You must know that everything that is in the ncx file is all you see in the left navigation window of AMIS player (and in the navigation windows of other Daisy players). Now consider the following example Introduction You see a "navPoint" element with two children "navLabel" and "content". Child of "navLabel" element "text" is used to display the text you want to appear in the left side of navigation window of AMIS player (and navigation windows of other Daisy players) which in this case would be "Introduction". The "src" attribute of "content" element is where you would tell the Daisy player to go to when it (Introduction) is clicked. Daisy player would get the value of the "src" attribute and look it into specified "smil" file and would run the matching element of "smil" file. Now lets see the value of "src" attribute in the above example. It is "YourSmilFile.smil#dtb0". "YourSmilFile.smil" is the name of your "smil" file and "dtb0" is the element in "YourSmilFile.smil" with an id equals to "dtb0". I hope this reply would be of some help in clearing your confusion. Zubair Younas. Note: I am afraid this forum would not accept xml tags. You can email me at zubairyounas@hotmail.com to get a detailed answer.

Thank you for your reply. If I understand you correctly you are saying that the text and audio referred to by the navInfo element is used by the player when the user navigates through the table of contents (global navigation) and the content element's src attribute is used when the user selects an item from the table of contents. So the navInfo text and audio is not used during normal playback or when the user moves between phrases which happen to be headings (local navigation). Am I correct to assume that the navInfo text and audio would always be the same as the text and audio referred to by the smil element pointed to by the navPoint content element? Meaning that the reference to the text and audio is repeated in order to save the player from having to access the smil while the user is moving through the table of contents. Nick

Yes! Its correct that navPoint element is used by the player when the user navigates through table of contents and the src attribute of content element is used to select an item from the table of contents. This is also safe to assume that during normal playback when the user goes through phrases, sentences or paragraphs which doesn't have any appearance in ncx file, navPoint is not used. But take the example of page numbers, you would normally like them to have in ncx file under "pageTarget" elements. So when you navigate through pages a player might be at ease following "pageTarget" element which would point to a smil element in its child "content" element, rather than searching it directly in your smil file. Zubair Younas.

Hi Nick, It was pointed out to me that AMIS should play the NavLabel before starting to play the SMIL content referenced by @content. We haven't addressed the issue yet, but it is described here along with a relevant use case: https://daisy-trac.cvsdude.com/amis/wiki/Limitations#SectionLabels However, it seems to me that this would possibly result hearing the section label twice, as it pretty much always appears in the SMIL content. NavLabels could be useful by themselves if you have a multi-volume book and the user is browsing the sections beyond those that exist on their current volume. So, no definite answers here - just some thoughts. I will bring this up in the DAISY 4 revision so that the next version of our standard is clearer. Marisa

This is exactly I wanted to ask. Thanks for the answers at least I dont have to post anything.