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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I suggest improving / making more flexible the canvas.toDataURL API<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The API is currently called with a second quality argument for the JPEG and WebP formats, and no second argument for the PNG format:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>toDataURL(type, quality); // JPEG and WebP<o:p></o:p></p><p class=MsoNormal>toDataURL(type); // PNG<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I suggest the following possibilities as well:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>toDataURL(“image/jpeg”, {<o:p></o:p></p><p class=MsoNormal> quality: 0..1,<o:p></o:p></p><p class=MsoNormal> grayscale: true/false, // since the JPEG format also supports grayscale images at smaller files sizes<o:p></o:p></p><p class=MsoNormal> progressive: true/false<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>For the WebP format, as far as I can see, Chrome currently doesn’t create an alpha channel.<o:p></o:p></p><p class=MsoNormal>Also, the possibility to create lossless WebP would be nice, I’m not sure if specifying a value of 1 for quality, accomplishes this.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>toDataURL(“image/webp”, {<o:p></o:p></p><p class=MsoNormal> quality: 0..1,<o:p></o:p></p><p class=MsoNormal> alpha: true/false,<o:p></o:p></p><p class=MsoNormal> alphaQuality: 0..1 (same as quality if omitted)<o:p></o:p></p><p class=MsoNormal> …<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>For the PNG format:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>toDataURL(“image/png”, {<o:p></o:p></p><p class=MsoNormal> interlaced: true/false,<o:p></o:p></p><p class=MsoNormal> grayscale: true/false,<o:p></o:p></p><p class=MsoNormal> alpha: true/false,<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Some means of creating 8bit color indexed PNG would also be nice.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>--<o:p></o:p></p><p class=MsoNormal>Sigurd Lerstad<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>