I have no idea why people would feel the need to fake footage, when there are so many real harrowing images that have already come out of Aleppo. There is no doubt that innocent people are dying needlessly, and that the situation for them is dire. Arguing about the validity of the situation only detracts from the real plight.
With all the photo shopping software available these days, and the fact that this software is so user friendly, almost anyone can alter videos and photos. Photographic evidence does not hold the same weight it used to. Now these images have to be examined by experts to determine their validity.
There are fake videos, photos, and articles all over the place. We cannot believe everything we see, but we do need to keep an open mind and see that there is pain and suffering happening. We cannot just assume that all of the things we see are false, but we have to be careful what we do believe.
Governments have often used propaganda in order to manipulate public opinion when it comes to conflict. There were many images that came out of Vietnam that were not truthful. It is well know that the United States used propaganda to make its case for World War II. This is no different today.