Wild Willy
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to Video Download Helper Google Group
I decided to take up my own challenge. I picked a video at random. It doesn't matter
which one it was. I'm sure they can all be handled the same as the one I did here. It
turns out the site is very helpful for anybody who wants to use ffmpeg to download their
content. They supply an HLS master manifest that is named master.m3u8 which makes it
very obvious in the Network Monitor. The only glitch is that you might have to reload
the web page once or twice to make the manifest appear. But it does appear.
I would expect HLS master manifests to be of type x-mpegurl. But that's just my primary
expectation. My secondary expectation is to see a master manifest show up as type
vnd.apple.mpegurl, which appears to be what this site favors. Whatever, as long as
there's a master manifest. The attached file shows how I downloaded this particular
video.
You'll notice that there are gibberish strings in the URL of the manifest I used. I draw
your attention to the one labelled &hash=, but there are also ?validfrom= and &validto=.
I believe -- I am not certain but my experience leads me to this guess -- that these
strings in the URL associate it exclusively with my visit to the web page. I also guess
that the URL is valid only for a limited time. If you try to use the URL that you can
copy/paste out of my attached file, I would be not at all surprised if it doesn't work
for you. So don't post about that. You have to visit these pages yourself. The URLs
you will get will have different gibberish strings that will work for you & nobody else.
I have to say I was rather surprised to discover we have Timed_ID3 data here. My
downloads from this site with VDH have always worked fine. Perhaps the Timed_ID3 data
causes problems for other people. My standards for what I have always gotten from this
site have always been rather low. I don't expect the technical quality of the video
files to be particularly high, meaning I expect the bit rates to be low, even for
1920x1080 content. You can see that in the case of the file I got here, the bit rates
are in the 1500-2000 kbps range. Good quality 1920x1080 content has bit rates in the
5000 kbps range. Very good quality is in the 6000-7000 kbps range. Great quality is
over 8000. But with the volume of content this site holds, they have to cut corners
somewhere, & video quality is where they do it. But if there are skips in the content I
have downloaded with VDH, I haven't been too fussed over it. I suspect that content
downloaded with VDH from this site is plagued by skips. The presence of Timed_ID3 data
would explain the skips. Downloading with ffmpeg lets you ignore the Timed_ID3 data, as
I did in this example. That should give you smooth playback, without skips.
Another word on that URL. You'll notice at the top of the file where I quote the ffmpeg
command I used, that every % is doubled. That's because I didn't just execute the
command. Typing a monstrosity like that every time I want to download something would be
insanity, or at least drive me to insanity. No, I issued the command from inside a
command script, a .Bat file. When you do that, you have to double each %. Look closely
lower down in the file, within the lines logged by ffmpeg. You'll notice that the same
URL appears but the % signs are all singletons. That is the real URL of the master
manifest, evidence that doubling the % signs is what the Windows command processor
requires if you want to make this work. If you really want to understand the issue of %
signs in .Bat files, search the web for answers.
After the completion of the ffmpeg command, I took some measurements. You can see that
in the attached file. One of the measurements is the download speed I got. You'll see
that it was pretty good in this case. I think this site is quite good about the speeds
it will give you for downloading its content. I have not usually seen speeds quite this
high, maybe more like half this. But maybe you get better speeds if you use ffmpeg.
Perhaps the Timed_ID3 data causes VDH to slow down. I don't know. I'm guessing. This
is not a site from which I frequently get content. Whatever the case, this site gives
much better service than YouTube.