What happens to your video after you have uploaded it to (anywhere)?
What happens to your video after you have uploaded it to iPlayerHD, or for that matter, any other video hosting platform? At iPlayerHD, our support folks are often asked about the upload process – where do the videos go? What does optimization really mean? Where do the videos go once they are processed? And the most important question – how do I prepare my videos for upload? In this post, I am going to address all of these and more. I’ll begin with the latter because no video platform, not iPlayerHD, not YouTube, or any of the others, can increase the quality of an ingested video. Beauty in, beauty out. So the video you upload should meet a certain standard if the optimized output files – those are the ones that are seen by your audience – are to look as good as they can.
How to prepare your videos for upload
Once your video is edited, most editing systems allow you to render your video in various formats and parameters. If the video is to go on DVD, for example, there are certain parameters you should use. If your video is to be viewed on the web, there are a different set of parameters you should use. No matter what, the video you render will be optimized (changed) by the platform you upload it to. Rarely is the video you uploaded seen by your audience. More on that later.
So, when rendering your video file for upload to a video hosting platform, use these parameters for the best results:
- Maintain your source resolution – that’s the resolution the video was shot as. For example, if the video was shot at 1920 x 1080, maintain that.
- Maintain your frame rate. It may be changed slightly during the optimization process but it is best to maintain the original rate.
- Maintain your audio as it was recorded. Your editing system will compress it a bit but the default setting will likely preserve the quality. Very little to do here.
- Render the video as H264 (codec) and use MP4 as the container. Think of the H264 codec as the recipe for your favorite salsa and MP4 as the container you put it in.
- And probably the most important of all is the video bitrate. Set that at 10 mbps or 10,000 kbps. On most platforms you upload your video file to, this bitrate will be reduced to something between 1,000 kbps and 10,000 kbps. So the source file should be at least as high as the highest file to be rendered during the optimization process. The highest is likely no more than 10,000 kbps though that’s rare. More likely, the highest quality file will be rendered between 2,500 and 5,000 kbps. Remember, quality cannot be increased and the video’s bitrate, the amount of data contained in every frame, has everything to do with the visual quality.
How to find the data about your video file
It’s good to know the bitrate of your video before it is rendered. Chances are very good that the video file ingested into your editor from your camera will be much higher than 10 mbps so rendering at 10 mbps is not a problem. If, however, your camera produced a video at less than 10 mbps, rendering at 10 mbps is problematic and could kill your video’s quality. So be sure your original video is at least 10 mbps.
There is a free tool I use to view a video file’s properties: MediaInfo. Once installed, go to your folder with the video name and right click over it. You will see this:
Click on MediaInfo and you will see this:
Here you see lots of data including the overall bit rate of 8262 kb/s (same as kbps). In the case of this video, assuming it is directly from your camera or is the result of your editing process, your final render should be no higher than 8262 kbps.
Uploading your videos
Now that you have the perfect video file, you need to upload it. Contrary to what many believe, video platforms have very little control over the upload process. That process is controlled through a combination of the browser used to upload, the internet service provider (ISP) and to a some degree, the uploader technology used by the video hosting platform.
The most important of these is the ISP and your router, or if using your mobile to upload, then the quality of your connection to your mobile provider is a significant factor. Your router is set by your ISP to upload at a certain speed based on your plan. More often than not, your plan’s upload speed varies greatly (it’s less) than your download speed. Video platforms have no control over the speed of the upload. That’s totally controlled by your ISP or mobile provider. In fact, platforms can take it a lot faster than you can send it.
When we are presented with a user whose files take a long time to upload, we often ask them to look at the uploader and tell us the speed at which the file is uploading. If it is slow, we recommend they ask their ISP for a faster speed. Often you can leverage “I am considering a move to your competitor” to obtain higher speeds at no additional cost. ISPs can simply send a signal to your router and the upload speed is adjusted. In some cases, if the router uses outdated technology, the ISP may need to send a new, updated router.
Possible upload problems
Sometimes uploading from businesses with restrictions on the use of the internet will block uploads. If your video never begins uploading and you are in a structured office environment, you should contact your network administrator and ask to have the site you are uploading to be white listed.
Other upload issues can be resolved by using a different browser. We’ve seen cases where an upload fails on one browser but succeeds on another. The most common Windows browsers are Internet Explorer, Chrome and Firefox and on Macs, Safari, Chrome and Firefox. Why one browser fails while another does not has always been a mystery. Another mystery is why a browser can fail today but succeed tomorrow. More often than not, it is some security issue managed by a machine that resolves itself somehow. Frankly, some things are better left unknown.
In very rare cases, we have seen where a file with a .mov container begins to upload and suddenly drops off. Another mystery. And extremely rare. In those cases, we have advised the user to simply change (rename) the file from filename.mov to filename.mp4. It’s a five second change that does not affect the playback of the video on the host machine and mysteriously solves the upload problem. Again, some things are better left unknown.
Large files = higher risk of uploading errors
The longer it takes a file to upload, the more likely there could be a failure during the process. Failure means the upload stops and must be restarted – from the beginning. So a fast upload speed is very helpful. Another factor to consider is the size of the file. If the video is several GB in size and the speed is slow – well, that is often a recipe for disaster. The upload is more likely to fail (though not necessarily) and your machine is tied up for a long time.
Assuming you have the best upload speed possible, then it is time to consider reducing the bit rate of the video you are uploading. More often than not, when we are presented with a user who has a multiple GB video file, the bitrate is well over 10 mbps. There is absolutely no advantage to uploading a video file with a bitrate over 10 mbps. I promise you, your super high bitrate video will never be viewed at that rate and the higher bitrate will not result in better quality. That applies to every video hosting platform. So there is no reason to upload a multiple GB video – unless the length of the video is significant. Consider this when rendering your video files for upload.
Video length and video size
The average video will be about 8 MB in file size for every one minute of video that is encoded at 1,000 kbps (1 mbps). Thus, one minute of video at 10,000 kbps is going to be about 80 MB. This is an approximate estimation though it is a safe one to use when calculating file size. A 10 minute video would be an 800 MB file and a 60 minute would be a 4.8 GB file. By the way, 1,000 MB equals 1 GB and 1,000 GB equals 1 TB.
After the upload is complete
So you have successfully uploaded your video file. What happens next? In the case of iPlayerHD, your file was uploaded to a bucket on Amazon Web Service’s platform. It is then immediately pulled from that bucket to a third party provider where the file is optimized in multiple files. Each of those files is configured for delivery to various device types and screen sizes. Small screen hand-held devices, for example, are delivered files with smaller resolutions and bitrates that make sense for the device. Hand-helds use much less bandwidth than desktops (desktops is used interchangeably with laptops) because desktops have much larger screens and are capable of delivering a much better viewing quality.
Once optimized, the new files are then stored in a data center somewhere in the world where they are accessed for viewing and downloading. The primary location for these files is generally called the origin. The first time a video is viewed from a certain location, let’s say Boston, the file is pulled from the origin to a server that’s located much closer to Boston (assuming the origin is not Boston). We call that second location the edge location. The machine playing the video is being served the video from that edge location. The purpose of the edge location is to deliver the video faster than if the video were to be delivered from the origin which is typically much further away. So the file is now located in two places.
Meanwhile, Down Under
If someone in Brisbane, Australia plays the video, the same process occurs and now the video is stored in three locations. Video files remain on edge servers so long as they are relevant – that is, folks from that area continue to watch the videos. Although the formula for maintaining files on edge locations varies greatly, at some point if the video goes unwatched, the file is removed from the edge. However, the file at the origin remains unless the user – the customer – deletes the video from their account. That action removes the video from the origin and all remaining edge locations.
Are you still awake?
This is a lot of information to digest. I get that. In fact, it’s sort of like a lullaby. Read it again sometime if you find yourself unable to sleep. On the other hand, it is very useful information and it will certainly make you smarter (for your business) though I don’t recommend you bring it up at a party. You may find folks walking away from you….or climbing a tree and taking a nap.