webm-alpha-2.html (3526B)
1 <!DOCTYPE html> 2 <html lang="en"> 3 <meta charset="utf-8"> 4 <title>Reftest that checks whether WebM video with alpha is rendered with the correct stride</title> 5 6 <style> 7 .edgeCover { 8 position: absolute; 9 box-shadow: 0 0 0 4px magenta, inset 0 0 0 4px magenta; 10 } 11 </style> 12 13 <div style="position: relative"> 14 <!-- 15 The video below was created as follows: 16 17 1. Run this code on the web console: 18 19 var c = document.createElement("canvas") 20 c.width = 334; 21 c.height = 334; 22 var ctx = c.getContext("2d") 23 ctx.fillStyle = "white" 24 ctx.fillRect(0, 0, 334, 334) 25 ctx.fillStyle = "red" 26 ctx.fillRect(0, 0, 64, 64) 27 ctx.fillStyle = "blue" 28 ctx.fillRect(64, 0, 64, 64) 29 ctx.fillStyle = "yellow" 30 ctx.fillRect(0, 64, 64, 64) 31 ctx.fillStyle = "lime" 32 ctx.fillRect(64, 64, 64, 64) 33 ctx.fillStyle = "black" 34 ctx.fillRect(196, 0, 16, 334) 35 c.toDataURL() 36 37 2. Save the PNG to a file called "frame.png". 38 3. Convert it to a WebM file using: 39 40 ffmpeg -framerate 25 -f image2 -i frame.png -c:v libvpx -auto-alt-ref 0 -pix_fmt yuva420p output.webm 41 42 (The "a" in "yuva420p" gives the video an alpha plane.) 43 44 4. Convert the WebM file to a data url. 45 46 The video size is 334x334. 334 is not divisible by 4. But 336 is divisible by 4 (and by 16). 47 --> 48 <video autoplay src="data:video/webm;base64,GkXfowEAAAAAAAAfQoaBAUL3gQFC8oEEQvOBCEKChHdlYm1Ch4ECQoWBAhhTgGcBAAAAAAAFFxFNm3RAO027i1OrhBVJqWZTrIHlTbuMU6uEFlSua1OsggEjTbuMU6uEElTDZ1OsggFwTbuMU6uEHFO7a1OsggT67AEAAAAAAACbAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAVSalmAQAAAAAAADIq17GDD0JATYCNTGF2ZjU4LjEyLjEwMFdBjUxhdmY1OC4xMi4xMDBEiYhARAAAAAAAABZUrmsBAAAAAAAAQa4BAAAAAAAAONeBAXPFgQGcgQAitZyDdW5khoVWX1ZQOIOBASPjg4QCYloA4AEAAAAAAAAMsIIBTrqCAU5TwIEBElTDZwEAAAAAAAC/c3MBAAAAAAAALmPAAQAAAAAAAABnyAEAAAAAAAAaRaOHRU5DT0RFUkSHjUxhdmY1OC4xMi4xMDBzcwEAAAAAAAA5Y8ABAAAAAAAABGPFgQFnyAEAAAAAAAAhRaOHRU5DT0RFUkSHlExhdmM1OC4xOC4xMDAgbGlidnB4c3MBAAAAAAAAOmPAAQAAAAAAAARjxYEBZ8gBAAAAAAAAIkWjiERVUkFUSU9ORIeUMDA6MDA6MDAuMDQwMDAwMDAwAAAfQ7Z1AQAAAAAAArPngQCgAQAAAAAAAqehQa+BAAAAECMAnQEqTgFOAQBHCIWFiIWEiAICIcB/gIxxQufgP4A9Lt4jh/4A/rBxoPYH9XeeA//cV4YH+A/zP1/7vF6v8OfS+b7aiY5ZAVRd7+B19e+R7TWdOyggwiXRbKr6e46ES8nODRmmsdHCSb2Ryky5CBdA85lugf/bcPq9FrVGK6E1Eq803lynCCqlTKr6e5sQVvvWkT2mnsucsPMn40e9aRPaae5uje+FHBKKfBFvcaiVeaazp2HiP9OnTp06dOw8R/p06dOnTp2HiP9OnTp06dOw8R/p06dOnTp2HiP9OnTp06dOw8R/p06dOnTp2HiP9OnTp06dOw8R/p06dOnTp2HiP9OnTp06dOw8R/p06dOnTp2HiP9OnTp06dOw8R/pvgD98nbATdAYGPgGEfqzwHaRDoh/yUJISQz2Qf1XrtcNhRYp///IKASH//40AA+zYdKbVnQlfxAlilLFiSS41KVx1DTCUxV9DmTS53pH2k1nrQQPyJ6ZE0aSsttOFtwAJ8cYL6BIAjpRqJ11YtY+TPfKFKdft0Uxv+1K+yvSpmFBL/U1Vr1TG8yIAHWhAQAAAAAAAOumAQAAAAAAAOLugQGlQNywGQCdASpOAU4BAEcIhYWIhYSIAgIABhYE9waBZJ9r25snOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsnOHsigP7/uoMAHFO7awEAAAAAAAARu4+zgQC3iveBAfGCAjvwgQM="></video> 49 <div class="edgeCover" style="left: 0; top: 0; width: 64px; height: 64px;"></div> 50 <div class="edgeCover" style="left: 64px; top: 0; width: 64px; height: 64px;"></div> 51 <div class="edgeCover" style="left: 0; top: 64px; width: 64px; height: 64px;"></div> 52 <div class="edgeCover" style="left: 64px; top: 64px; width: 64px; height: 64px;"></div> 53 <div class="edgeCover" style="left: 196px; top: 0; width: 16px; height: 334px;"></div> 54 </div>