description("Test if putImageData gives back the same result as getImageData"); var ctx = document.createElement('canvas').getContext('2d'); ctx.fillStyle = "red"; ctx.fillRect(0,0,50,20); ctx.fillStyle = "green"; ctx.fillRect(50,0,50,20); ctx.fillStyle = "blue"; ctx.fillRect(100,0,50,20); var data = ctx.getImageData(0,0,150,20); ctx.putImageData(data, 0, 20); var imageData = ctx.getImageData(1, 21, 48, 18); var imgdata = imageData.data; shouldBe("imgdata[4]", "255"); shouldBe("imgdata[5]", "0"); shouldBe("imgdata[6]", "0"); imageData = ctx.getImageData(51, 21, 48, 18); imgdata = imageData.data; shouldBe("imgdata[4]", "0"); shouldBe("imgdata[5]", "128"); shouldBe("imgdata[6]", "0"); imageData = ctx.getImageData(101, 21, 48, 18); imgdata = imageData.data; shouldBe("imgdata[4]", "0"); shouldBe("imgdata[5]", "0"); shouldBe("imgdata[6]", "255");