- From: Andreas Tai <tai@irt.de>
- Date: Mon, 27 Oct 2014 12:07:54 +0100
- To: Thierry MICHEL <tmichel@w3.org>
- CC: Nigel Megitt <nigel.megitt@bbc.co.uk>, Pierre-Anthony Lemieux <pal@sandflow.com>, W3C Public TTWG <public-tt@w3.org>
Hi Thierry, First congratulation to the very good spec document! Apart from a few issues most of my observations are not critical. They can be seen more as a proposal for the editor. I am sending the comments on my behalf. The more important issues first: ---------------------------------- 5.2 Foreign Elements and Attributes ----------------------------------- It would be good to give more emphasis that a presentation processor should not reject a document "with foreign namespace elements or attributes". Examples for possible edits: a) "...*The subtitle document SHALL be processed but* such elements and attributes may be ignored by the presentation processor or transformation processor." b) "A *conforming* subtitle document may contain elements and attributes that are neither specifically permitted nor forbidden by a profile." It may be a good idea to align this paragraph with the section in TTML 5.3.2. As far as I can see it is not explicitly forbidden to use the IMSC namespaces for extensions. So either in IMSC 1 5.3 or somewhere else an additional constraint may be added. ----------------------------------- 5.10 Features (Common features) #length-cell feature ----------------------------------- IMSC 1 states that the #length-cell feature shall not be used. The line-padding extension uses the cell metric. Not sure if this causes a problem. On the one hand the extensions are "outside" of TTML 1 on the other hand they use the cell metric as defined by TTML 1. ----------------------------------- 5.10 Features (Common features) -#length feature ----------------------------------- The #length feature includes the support of the "c" metric (http://www.w3.org/TR/ttml1/#feature-length). So you may add a restriction here. Some other observations in document order: ------------------------------ 3. Conformance ------------------------------ The term "subtitle document" is not defined in IMSC 1 and TTML 1 but used frequently in a normative context. It may be helpful to define it in Section 2. ------------------------------ 4.1 General ------------------------------ From IMSC 1: "In addition, the Text Profile subtitle document SHOULD be associated with the Image Profile subtitle document such that, when image content is encountered, assistive technologies have access to its corresponding text form." As far as I could see there is no defined method to link a Text profile document to an Image Profile document through an element in the document themselves. So it may helpful to add that his has to be done through an external setting. ------------------------------ 5.7.3 itts:forcedDisplay - value matrix ------------------------------ In general I would welcome a bit more text about the details of value combinations. There is text for "displayForcedMode=true, itts:forcedDisplay=false" but not for "displayForcedMode=true, itts:forcedDisplay=true". Maybe a matrix would be helpful with tts:visibilily (visible, hidden), displayForcedDisplay parameter (true, fase) annd itts:forcedDisplay (true, false). ------------------------------ 5.7.3 itts:forcedDisplay - Informative Note ------------------------------ The first note could possibly be improved if it is noted that this has an effect only if a "non-transparent background" is directly defined for the region (e.g. in most cases I have seen for the usage of EBU-TT-D the background will be applied through the content elements). ------------------------------ 5.7.4 ittm:altText - Optionality of attributes ------------------------------ For the XML Representation you may repeat the part from 2.3 TTML 1 where it states that bold-face attribute names are required and the others are optional (personally I would prefer the keyword "REQUIRED" after the attribute name). Without that it may not be clear if the attributes are optional or required. ------------------------------ 5.7.4 ittm:altText - Typo ------------------------------ End of "Note:": Replace ". ." with "." ------------------------------ 5.10 Features (Common) ------------------------------ #timing: It may be helpful to describe what you mean with the same syntax (e.g. is 00:00:01, 00:00:01.0 and 00:00:01.000 a different syntax?) ------------------------------ 6.3 Features (Text Profile) ------------------------------ #textAlgin: A reference to the definition of the "defaultRegion" in TTML 1 would be helpful. I assume that ony the TTML experts know what the defaultRegion is (e.g. some implementers gave in a TTML document "defaultRegion" as value for xml:id). ----------------------------- 8.2 Reference Fonts ----------------------------- A reference to presentation processors and transformation processors may be helpful. A presentation processor SHALL lay out the text according to the metrics and a transformation processor should use this metrics for any calculation. ------------------------ Annex B Forced Content ------------------------ A code example may be an illustrative help for the shown use case. Best regards, Andreas -- ------------------------------------------------ Andreas Tai Production Systems Television IRT - Institut fuer Rundfunktechnik GmbH R&D Institute of ARD, ZDF, DRadio, ORF and SRG/SSR Floriansmuehlstrasse 60, D-80939 Munich, Germany Phone: +49 89 32399-389 | Fax: +49 89 32399-200 http: www.irt.de | Email: tai@irt.de ------------------------------------------------ registration court& managing director: Munich Commercial, RegNo. B 5191 Dr. Klaus Illgner-Fehns ------------------------------------------------ Am 03.10.2014 um 16:32 schrieb Thierry MICHEL: > Pierre, Nigel, TTWG, > > Now that we have published the IMSC1 WD for wide review, we should be > tracking incoming comments on public-tt@w3.org. > > If there are comments coming in, we should discuss those, by email or > during calls, or at F2F and come to a WG resolution. Then the WD > should respond to each commenter to collect his approval. > (We don't necessary have to accept the proposal from the commenter, > but if we don't, we should explain why it is only partially > adopted/postponed or rejected/, etc. > Finally, if the commenter does not agree to our resolution, we will > make our case to the Director. > > In parallel we should start working on the CR draft. > > Therefore I have drafted the SOTD section [1] for this CR, that > Pierre may incorporate in his document. > > Please look at the exit criteria and the end date of CR (set for 31 > dec 2014), and let's discuss those. > > Thierry. > > > [1] https://www.w3.org/2014/09/WD-ttml-imsc1-20141014/ > > > -- ------------------------------------------------ Andreas Tai Production Systems Television IRT - Institut fuer Rundfunktechnik GmbH R&D Institute of ARD, ZDF, DRadio, ORF and SRG/SSR Floriansmuehlstrasse 60, D-80939 Munich, Germany Phone: +49 89 32399-389 | Fax: +49 89 32399-200 http: www.irt.de | Email: tai@irt.de ------------------------------------------------ registration court& managing director: Munich Commercial, RegNo. B 5191 Dr. Klaus Illgner-Fehns ------------------------------------------------
Received on Monday, 27 October 2014 11:08:42 UTC