In the book you use your imagination because you get to visualize what the characters look like, but in the movie all of the creativity is done for you. Books are fun to read because you get to imagine what things look like, but when you watch the movie it can ruin your image of the character. In the movie Jonas is 16, but in the book Jonas is 12. If you are imagining Jonas as a 16 year old while you are reading the book because you watched the movie it ruins your visual of the character.
Also, in the book the Chief elder isn't a big problem, it is really her and the community, together. However, in the movie the Chief Elder is a whole new villain. The movie created another conflict of Jonas V. the Chief elder, where in the book that conflict would have been Jonas V. society. In the book the Chief Elder doesn't know any better. She along with everyone else in the community, besides The Giver and Jonas, think they are doing the right thing. Nevertheless in the movie the Chief elder is evil, and although she thinks she is doing the right thing, it is much more obvious that she isn't.
Finally, the end of the book is open to interpretation, but in the movie it tells you that Jonas finally found a place with love. The book allowed you to be creative and think of your own ending. Yet, in the movie it gives you one. The movie shows Jonas in front of the house decorated in lights. Some might say that the book has the same ending as the movie, and to disprove that I am going to give an example of another possible ending. As you know Jonas was in the snow for a very long time, and it is very likely that he could have gotten hypothermia. One of the symptoms of hypothermia is hallucinating. It is possible that in the end of the book Jonas got hypothermia, and died.
In conclusion, the movie The Giver is way worse than the book. One reason why is because in the book the Chief Elder wasn't a problem as much as her and the community combined, but in the movie the Chief Elder is a villain. Also, the book allows you to imagine the characters and what things look like, the movie takes away the fun and creativity by doing it all for you. Lastly, the end of the book lets you use your imagination by allowing you to think of an ending, but the movie tells you what happened and sucked the fun out of the whole thing.