baby.js:104 Uncaught TypeError: Cannot read property 'width' of undefined

源码是这样的：

var babyBodyCount = this.babyBodyCount;

ctx1.drawImage(babyBoby[babyBodyCount], -babyBoby[babyBodyCount].width * 0.5+23, -babyBoby[babyBodyCount].height * 0.5);

报错如下：

baby.js:104 Uncaught TypeError: Cannot read property 'width' of undefined

    at babyObj.draw (baby.js:104)

    at gameloop (main.js:111)

    at game (main.js:37)