Alexander Kremenets 덕분에 필자는 필요한 코드를 정리할 수있었습니다. Alexander가 연결된 question의 Hermite resize을 사용했습니다. 다른 질문의 코드도 다음과 같이 조합됩니다.
var originalCanvas = document.getElementById("c");
// Create canvas for resizing
var resizeCanvas = document.createElement("canvas");
resizeCanvas.height = originalCanvas.height;
resizeCanvas.width = originalCanvas.width;
var resizeCtx = resizeCanvas.getContext('2d');
// Put original canvas contents to the resizing canvas
resizeCtx.drawImage(originalCanvas, 0, 0);
// Resize using Hermite resampling
resampleHermite(resizeCanvas, resizeCanvas.width, resizeCanvas.height, 150, 90);
// Use the resized image to do what you want
var image = resizeCanvas.toDataURL("image/png");