The horse in motion (Eadweard Muybridge) 1878 First Film Ever
For sure, the rendering process and video resolution is the one that makes not everyone dedicate to offering this type of service.
It is not the same the realization of a still image, even it has lot of resolution that has the calculation of thousands of frames.
In that sense, the calculation capacity of your company is a determining filter.
You already know what it costs for your computer to calculate an image of a complex scene with millions of polygons at a certain resolution.
But what number of frames and resolution do I need to calculate to make an animation?
How many images will I have to calculate?
As you know, the magic of cinema is based on the reproduction of 25 frames per second. There are other formats depending on the country that oscillate between 25 and 30 frames per second.
If we assume that, on average, video architecture visualizations last between 2 and 4 minutes, we will consider for our calculations a duration of 3 minutes. This is the first account you must do:
3 minutes = 180 seconds
180 x 25fr / sec = 4500 frames
You will need to create 4500 images. It is certainly a substantial change over a work of fixed images where usually 5 to 10 images are made on average.
Obviously, we should not think that the work is multiplied by 450. The animation consists of obtaining results by interpolation. I will explain myself better: we mark our initial and final frames of each sequence and the computer is in charge of interpolating the definition of position of the camera in time.
However, do not worry, there are solutions.
Basically there are two: having a “render farm” or hiring services in the cloud to get the desired video resolution result.
But, at what video resolution?
You already know the importance of resolution when calculating a still image derived from the need to be printed.
Fortunately, although for an animation we have to calculate many more images as we have just seen, the video resolution of them for the moment is less. Yes, I said for the moment.
A few years ago, the PAL DVD resolution was the usual (720×576 px). It was more than enough, it was the video resolution of the DVD format. What’s more, in previous years, a video resolution of 640×480 was the usual.
Unfortunately for our interests as “image calculators” are increasingly requested formats with higher resolution.
The biggest stopper is the calculation but it also influences the post-production process, although to a lesser extent.
The question that we must ask the client is on which platform he will want to show our work.
HD video resolution
If the media is your web page, the HD format (1280X720 px) is more than enough. The decision is limited by the player. That is, even if it is a presentation with a large screen, this format will meet expectations.
Do not get confused…
It is a common mistake to think that a resolution of 640×480 is more or less half that of a HD resolution of 1280×720. The neophytes fall into this error and when they launch the animation they think it will cost them to calculate it, more or less double. We come to a more approximate idea of the difference of calculation if we do a simple operation:
640×480 = 307,200 pixels
1280×720 = 921,600 pixels
921,600 / 307,200 = 3
This is not the double: it is the triple.
FULL HD video resolution
Nowadays, early 2017, the standard resolution format is this: FULL HD (1920×1080). If we perform the previous multiplication:
1920×1080 = 2,073,600 pixels, that is, 2.25 times the HD format.
It is becoming more common the televisions that support this format and, consequently is the most requested format. You just have to see the proliferation of TV channels in this format.
FULL 4K video resolution
Unfortunately for our interests, the trend does not reduce the quality of the image, rather the other way, increase it more and more.
It has been long time since the televisions are able to show this format (4096×2160) in the market. Let’s recalculate the operation:
4096×2160 = 8,847,360 pixels
That is, the same resolution we need to print a paper image in DIN A3 format.
Buffff … yes, that’s right, it’s too much.
So ask yourself this question, if on your computer (which for sure is not a bad one) you need 6 hours to calculate a complicated scene, …
How much time will I need to calculate one minute of full 4K animation?
25 x 60 x 6 = 9600 hours = 375 days = 1 year
It is no time to get depressed. But yes, we must be aware of our limitations before committing ourselves to our client.
The conclusion is obvious: to do animation we need and we will need more and more computing capacity.
That forces us to invest money in machines and ram or to contract the services of calculation in the cloud.
In relation to the subject of compression, one of the most common mistakes is to think that our sequences should be stored without compression as if that way we guarantee that the quality was maximum.
If we would do so, the resulting files would soon fill our hard drive.
My recommendation is that you use the Apple ProRes compression codec.
I think it’s the perfect balance between image quality and file size. It is the one we use both for the delivery of the final work and for the entire production process.
Do you want to discover the third secret? : SECRET 7 | Render animation : lights, camera and … action!