Add animated gif

[olgabot]

Adds an animated GIF to the README so newcomers to the package can get a sense of what TensorBoard is without having to install it.

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[jart]

I like this gif. Is there any chance we can make it larger and without dithering? If you make a YouTube video demo I actually know a few tricks with youtube-dl and ffmpeg to make a really nice gif.

[olgabot]

What are your favorite ffmpeg commands? I did this:

ffmpeg -i tensorboard.mov -s 600x400 -pix_fmt rgb24 -r 10 -f gif - | gifsicle --optimize=3 --delay=3 > tensorboard.gif 

[jart]

I would have to look at my notes on my home computer, which I can do later tonight. The secret I've used is basically to find the flag that changes the dithering algorithm. Then keep trying different values until it produces something that looks fabulous.

[jart]

OK so I took a look at my notes file. I had a lot of success with this ffmpeg command once when making a GIF that had a lot of vector graphics.

ffmpeg -i foo.mp4 -strict -2 -ss 00:05:15 -t 00:00:12 -async 1 \ -vf scale=640:360:-1:sws_dither=a_dither cut.gif

[chihuahua]

Thanks! Yeah, a graphic above the fold in the README is much needed!

[jart]

New commit looks a lot better. If you're able to create a high quality YouTube video, I could try playing around with ffmpeg and see what sort of gif I can make too.

[olgabot]

@jart how's this gif looking to you? It could be sped up a little but I think it looks nicer

[olgabot]

I've uploaded it here: https://www.youtube.com/watch?v=ktoyJgpq8Ms&feature=youtu.be

[olgabot]

ping - any updates?

[dvaldivia]

@olgabot I think you are missing the CLA