HTML Development
HTML Best Practices
HTML Content Restrictions
10min
these content restrictions are associated with html pages web browsing brightsign players are not intended for use as general purpose web browsers it is best to think of brightsign units as html players with interactive capabilities, not web surfing tools each page should be thoroughly tested before being used as digital signage flash content brightsign players do not support flash content any html pages that have embedded flash content will not display correctly most flash authoring applications, including the adobe creative suite, have tools that allow you to export flash content as html video see the html video docid\ e6ujleh69q0jmmv8kytrp page for usage rules regarding html video 4k graphics while many brightsign models can output 4k video modes (3840x2160), not all of these models can render html at 4k xtx44, xtx43 the xtx44 and xtx43 models support a native 4k html graphics plane (see full resolution graphics docid\ tjnw230kcx6i9tnihfcvd for more details) note the following performance restrictions when using native 4k html graphics animations will not exceed 20 fps (and intensive animations may exhibit very low framerates) non hwz video is likewise limited to 20 fps, so html video docid\ e6ujleh69q0jmmv8kytrp should be enabled for video elements in native 4k we recommend displaying only one or two 4k images at a time (for example, a slideshow with one image displayed and next image preloaded) images should not exceed 3840x2160 in size we recommend using rovirtualmemory docid\ m2dqxiy5mgoraosa8mvni if possible pages that use many layers may run out of memory in native 4k enabling the rovideomode docid\ qq734nqz0hcwni0unsdmp setting may help mitigate this issue xdx34, xdx33, hdx24, hdx23, ls424, ls423, 4kx42 the xd, hd, ls, and 4k models support graphics up to 1920x1200 (see full resolution graphics docid\ tjnw230kcx6i9tnihfcvd for more details), which can then be upscaled to a 4k video mode pages must be specified as 1920x1080 (or 2048x1080 for dci 4k); they can then be upscaled to 4k pixel sizes and coordinates with 4k modes as noted above, webpages are often upscaled when outputting a 4k video mode relative css property values will scale automatically, but pixel values may need to be modified to account for differences between 4k video and graphics see rorectangle docid 3e73tpeml1 oebs2goauq for more information about using coordinates with upscaled video modes image sizes images larger than 2048x1280x32bpp (or 3840x2160x32bpp for xt, 4k, xtx34, and xdx33 players) will not be displayed by default if a 4k video mode is used, the player will upscale images from hd resolution accordingly (though native 4k graphics can be enabled on the xtx43) the default limit can be increased in brightscript using the rovideomode docid\ qq734nqz0hcwni0unsdmp method without altering the default maximum resolution, you can increase the maximum width of images by sacrificing height (e g using a 3840x640x32bpp image on non 4k players is allowed) you can also increase the maximum width/height by reducing the bpp value (e g using a 3840x2160x16bpp on non 4k players is allowed) for performance reasons, we recommend against downscaling images this consumes considerably more resources than either displaying images at their native size or upscaling them memory and performance the amount of memory available for html applications varies by model and player series series 5 players unlike series 4 and older players, series 5 players don’t have pre allocated graphics and system memory there are limitations on gpu memory in chromium so that demanding gpu applications don’t deplete that memory series 4 and older players xtx43, xtx44 512mb for graphics; 512mb for javascript xdx33, xdx34 256mb for graphics; 512mb for javascript hdx24 460mb for graphics; javascript tbd ls4x5 280mb for graphics; javascript tbd hdx23/ls423/ho523 256mb for graphics; 128mb for javascript notes the memory available for graphics can be reduced by a number of factors, including the number of css layers, the complexity of animations, and the use of webgl the javascript memory is subject to a hard limit if there is no javascript memory after garbage collection, chromium will terminate the active process each html widget has its own javascript heap, so it's possible to overcommit javascript memory if multiple html widgets are active often, the best way to improve graphics performance is to ensure that images are scaled to the desired output resolution before they are rendered in html use the debugging webpages docid 4qlk1krr1cnx7xypwxry5 to determine the amount of resources being used by a webpage web fonts if a font file is not included and referenced by the html page, text will be rendered using a default system font while functional, the default font has little aesthetic appeal, so we recommend including font files for most digital signage applications supported font types include truetype font files ( ttf ), opentype font ( otf ), and web open font files ( woff , woff2 )