{"action":"created","issue":{"url":"https://api.github.com/repos/w3c/webvtt/issues/279","labels_url":"https://api.github.com/repos/w3c/webvtt/issues/279/labels{/name}","comments_url":"https://api.github.com/repos/w3c/webvtt/issues/279/comments","events_url":"https://api.github.com/repos/w3c/webvtt/issues/279/events","html_url":"https://github.com/w3c/webvtt/pull/279","id":120396756,"number":279,"title":"Fix #270: Add classes to specify text color","user":{"login":"zcorpan","id":244772,"avatar_url":"https://avatars.githubusercontent.com/u/244772?v=3","gravatar_id":"","url":"https://api.github.com/users/zcorpan","html_url":"https://github.com/zcorpan","followers_url":"https://api.github.com/users/zcorpan/followers","following_url":"https://api.github.com/users/zcorpan/following{/other_user}","gists_url":"https://api.github.com/users/zcorpan/gists{/gist_id}","starred_url":"https://api.github.com/users/zcorpan/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/zcorpan/subscriptions","organizations_url":"https://api.github.com/users/zcorpan/orgs","repos_url":"https://api.github.com/users/zcorpan/repos","events_url":"https://api.github.com/users/zcorpan/events{/privacy}","received_events_url":"https://api.github.com/users/zcorpan/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":9,"created_at":"2015-12-04T12:57:47Z","updated_at":"2015-12-11T17:45:51Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/w3c/webvtt/pulls/279","html_url":"https://github.com/w3c/webvtt/pull/279","diff_url":"https://github.com/w3c/webvtt/pull/279.diff","patch_url":"https://github.com/w3c/webvtt/pull/279.patch"},"body":"Same colors as CEA608, excluding blue and black.\r\n\r\nCloses #272.\r\n\r\nIssue: #270"},"comment":{"url":"https://api.github.com/repos/w3c/webvtt/issues/comments/164001255","html_url":"https://github.com/w3c/webvtt/pull/279#issuecomment-164001255","issue_url":"https://api.github.com/repos/w3c/webvtt/issues/279","id":164001255,"user":{"login":"dwsinger","id":11635897,"avatar_url":"https://avatars.githubusercontent.com/u/11635897?v=3","gravatar_id":"","url":"https://api.github.com/users/dwsinger","html_url":"https://github.com/dwsinger","followers_url":"https://api.github.com/users/dwsinger/followers","following_url":"https://api.github.com/users/dwsinger/following{/other_user}","gists_url":"https://api.github.com/users/dwsinger/gists{/gist_id}","starred_url":"https://api.github.com/users/dwsinger/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/dwsinger/subscriptions","organizations_url":"https://api.github.com/users/dwsinger/orgs","repos_url":"https://api.github.com/users/dwsinger/repos","events_url":"https://api.github.com/users/dwsinger/events{/privacy}","received_events_url":"https://api.github.com/users/dwsinger/received_events","type":"User","site_admin":false},"created_at":"2015-12-11T17:45:51Z","updated_at":"2015-12-11T17:45:51Z","body":"\n> On Dec 11, 2015, at 7:03 , Andreas Tai <notifications@github.com> wrote:\n> \n> I reached out to some partners in the HBB4ALL project and so far I did not get any objection. For me the commit seems to me like a reasonable basic solution that covers the minimal requirements regarding the use of text color.\n> \n> I got the following feedback from two Spanish partners. One of them analysed the the AENOR Norm UNE 153010:2012 Subtitulado para personas sordas y personas con discapacidad auditiva in respect to the proposal:\n> \n> In principle, the solution you propose fulfils the requirements of the Spanish code of good practice. The colour is used to distinguish the characters in Spain, as said. This code does not contain a list of possible colours, but a rule to ensure two colours are different enough. The rule is the \"colour difference\", evaluated as the sum of the absolute value of the differences in each RGB value. If you consider two colours, identified by RGB values (8 bits) (R1G1B1 and R2G2B2), you calculate the \"colour difference\" as |R1-R2| + |G1-G2| + |B1-B2|. According to the code, this result must be at least 255 to ensure the colours are different enough. The colours you propose fulfil this requirement, although I am not sure in the case of the red.\n> \n> Regarding to the background, a box is not mandatory. The only requirement is to keep a contrast ratio of at least 4,5 between text and box/contour. And this \"contrast ratio\" is calculated according to WCAG 2.0 (http://www.w3.org/TR/WCAG20/#contrast-ratiodef). I am not sure, but an opacity of 0.8 may ensure a good contrast whatever the colour of the video at that moment behind the box.\n> \n> With regards to blue, it was used for the lyrics of a song (on yellow background in the case of teletext) but this just applies to \"legacy subtitles\".\n> \n> So, I think your basic solution is globally valid according to this code.\n> \n> The other spanish partner mentioned:\n> \n> I would try to mention that red should be avoided.\n> \n> From a German broadcaster I got the following feedback:\n> \n> The proposal looks fine to me. It make sense to me to disallow blue when the background color is black. If blue would be allowed there should also be the possibility to set the background color.\n\nGreat research, thanks!\n\nso, the idea is to say that a user-agent not supporting CSS must nonetheless support coloring via a set of named classes which are (all of | a subset of) the color classes from the x08 styles, and should also allow the user to over-ride what color is shown for a given class. \n\noh, and VTT files using those classes must, of course, explicitly include a style-sheet defining them, for the CSS-aware UAs.\n\n??\n\nDavid Singer\nManager, Software Standards, Apple Inc.\n\n"}}