Hi all ! This is my first try at a HD 360 degree video to be uploaded to Youtube.
My first goal was, as recommended by youtube to upload a 8192 x 4096 video to get the full 4K 360 degrees experience. So that’s exactly what I tried to do. As you will see here under, that mission was more difficult than first expected.
First a little Warning : File size while working in those resolutions can be huge, especially using uncompressed video files. Check that you’ve got enough free hard drive space (> 100 Go, depending on the video length of course) before starting.Also working with such files can obviously lead to very long processing and rendering time. I included some various rendering times that might be helpful to estimate the length of the process.
Here are my laptop specs
Windows 7 64 bits
32 Go DDR4
I7 4700MQ @ 2.4 Ghz
Working on regular 1.5 To HDD 7200 r/m
1. Create the content
I made the content of my first video using [Fragmentarium] with a modified glsl snippet based on archive. The Fragmentarium version I used is [Fragmentarium-1.0.30-3Dickulus] which has allows to make spline cam paths, among some other very interesting features. I might publish the source code later on.
[Fragmentarium] outputs a sequence of uncompressed files (BMP). For my first test I used 3500 pictures, rendered at 8192 * 4096. I will not go into details about the rendering process but it took about one week to render the files on a GTX 980ti.
2. From BMP to uncompressed AVI
As my output is a list of BMP files my first task is to render the sequence as a full video file. I tried to output a mp4 file using various tools but all of them crashed, ran out of memory or did other random stuff I wasn’t look for. I could of course have used [ffmpeg] for the whole process but I was using my windows laptop and I first thought my usual tools would do the job easily.
Using the trusted and open-source VirtuaDub I first made an uncompressed avi file with the correct size and frame rate settings. Virtudub automatically understands that a list of ordered bmps or jpgs are frames of a video sequence.
Here are some render times to meditate on :
4096 * 2048 : 12 minutes for a 800 frames file
8192 * 4096 : 25 minutes render time, 80 Go file
4096 * 2048 : 6000 frames, about one hour, 140 Go
7168 * 3584 25 minutes render time, 60 Go file
4096 * 2046 : 9000 frames, 1 hour 15 minutes, 261 Go, 60 fps
3. Who likes 8192 * 4096 ?
The answer is simple : nobody. I tried various tools but after a while I settled on a lower resolution, I used [Virtuadub] to resize the video to half-size, that is 4096 * 2048. I have tried a successful workflow using h.265 but apparently youtube doesn’t like that yet.
Ok now I have a 150 Go audioless video file and lost a few yours to get to this point which luckily you can avoid losing if you are reading this.
After a few tries I went to [Handbrake]. Handbrake is open-source and has a cocktail and a pineapple as a logo, that’s a good sign. Back to handbrake. First good news, It didn’t crash on startup. Back to h.264. Again, handbrake, conversion and upload. My first test with a low resolution works.
When you first load the file in handbrake, the software does a process called tile scanning. That process did freeze when using the 8192 * 4096 resolution.
That’s why I settled for half-size resolution at least for a first try.
4096 * 2048 800 frames in h265 : 5 minutes render time
4096 * 2048 800 frames in h.264 : 6 minutes render time
4096 * 2048 6000 frames in h.264 : about 40 minutes render time
4096 * 2048 9000 frames in h.264 : about one hour
4. add metadata
Last but not least, my video lacks any audio. FFmpeg allows for an easy merge with an audio file using the following command :
ffmpeg -i input_audio.wav -i input_vid.mp4 -vcodec copy output.mp4
5. add metadata
Youtube provides a tool to add the metadata necessary to be recognised as a 360 degree video. This tool is available for free [here]. It’s very simple to use, just open the file, inject the metadata and save.
6. Upload patiently
Drink a beer, enjoy a coffee, it’s going to take a while. The upload is of course going to be longer than usual because of the filesize but the youtube processing also seems to be much longer.