DWHelper does not detec PL1_TV videos

[James Cognito]

Hello.

Sample link is: https://pl1.tv/title/panikarze-pandemiczni-i-klamstwa-szczepionkowe/

It does not detect a video for me from the link above.

Can anyone suggest what to do to make it possible to detect the link and download a video ?

[Wild Willy]

Good problem report. Thank you!

I visited that page & without even launching playback, I got what you can see in the
attached image. I noticed that the variant I have labeled 1 had a resolution but the
variant I have labeled 2 did not. This led me to believe I was looking at one of those
situations where VDH was recognizing the video & audio as separate variants. So I
downloaded both of those. The variant I have labeled 3 was exactly double the correct
duration. I don't know what that means. I decided to ignore that one.

It turned out that both the variants I downloaded had both video & audio. They appeared
to be the exact same video. I played each one in VLC. I did not sit & watch them, just
sampled them at 1-minute intervals to make sure I had both video & audio all the way to
the end, which I did in both files. Of course, I have no idea what the guys in the video
were talking about since I don't speak Polish.

I am running Windows 7 64-bit, Firefox 105.0.3 64-bit, licensed VDH 7.6.3a6 beta, CoApp
1.6.3. The beta is, as far as I know, equivalent to the recently released general
availability public version 7.6.3, which is actually not yet available on the Mozilla
site. But you can get the beta, as usual, from the VDH web site. That is the only
difference between your system & mine, as far as I can tell.

I did not even have to launch playback of the video & VDH gave me the variants I
downloaded. It's possible that you might have to click the Play button on the video in
the web page & let the video play for a couple of seconds in order to make VDH recognize
the video. But why you would have to do that & I did not would be a mystery to me.

[jcv...@gmail.com]

Worked for me too. Downloaded the 2nd one. Plays fine in VLC.

jerome

[James Cognito]

Alright, Ive made some steps to reproduce the problem, or to fix it somehow...

And generally, I had to unblock the CompanyApp to connect throughthe Internet (?! why ???).
So yes, it worked for detecting a video stream.

But still there were errors. So I tried to remove and then install again a CompanyApp.

But unfortunately just after trying to download using a "download" option, it gives me an 404 error.

error log from VDH:
     
Abortedmoz-extension://f4b8cabf-1772-42c2-9c57-d8e5c4988085/background/main.js:1 value@moz-extension://f4b8cabf-1772-42c2-9c57-d8e5c4988085/background/main.js:1:152890 value@moz-extension://f4b8cabf-1772-42c2-9c57-d8e5c4988085/background/main.js:1:142032 444/value/<@moz-extension://f4b8cabf-1772-42c2-9c57-d8e5c4988085/background/main.js:1:75607 8086/value/<@moz-extension://f4b8cabf-1772-42c2-9c57-d8e5c4988085/background/main.js:1:140530

screenshots attached:

https://ibb.co/zhdYGF1
https://ibb.co/bWt5SLP

What am I doing wrong ?
I was testing it using the link from my first post here.

So this one: test link

[Wild Willy]

I went to your page & got what you can see in attached image #01. Looked normal enough
but when I tried to download the variant, I also got the same 404 Not Found error you
did. So I did my usual thing trying to see if maybe ffmpeg could get this. I opened the
Network Monitor & found 4 manifests, as you can see in attached image #02. I ran ffprobe
on all 4 manifests & got the same error. I have attached the 4 ffprobe reports. In the
first ffprobe report, scroll down to about line 40. You will see a 404 Not Found message
for something that appears to be some kind of key file. The error is a bit easier to
find in the other 3 ffprobe reports, but it's the exact same error. I have two
hypotheses about what's going on here.

1. Somebody has accidentally forgotten to put the file in question on the web site. If
it's not there, we can't download this.

2. Somebody has intentionally not put the file in question on the web site. This would
be for the purpose of thwarting downloaders. But the effect is the same, that we can't
download this.

It's weird. It all worked for me back in October, about 6 weeks ago. They've done
something to the web site & now you can't download from there. So you're not doing
anything wrong. The web site has determined that we are not supposed to download their
content. If you're desperate to have your own copy of this, use a screen recorder to
record playback of the item. That is not as good as downloading. For one thing,
recording it will take as long as whatever the duration is of the video. For another,
you probably won't be able to use your computer for anything else while you're making the
recording. But that's the price of a screen recorder. I have OBS but I'm not endorsing
it. I have not researched screen recorders & I have not used any screen recorder other
that OBS. Maybe it's the best, maybe not. You'll have to decide.

[Wild Willy]

Oops. Forgot to answer one of your questions. The CoApp is where the code resides that
downloads content from the Internet. So it has to have access to your Internet
connection. Blocking it is going to prevent VDH from working. But you already figured
that out.

But that raises an interesting question. Maybe you've blocked something else that is
preventing VDH from working. You'll probably have to go through the tedious task of
unblocking certain things one by one & retrying your download. You should do that to
everything. Don't tell yourself oh this can't possibly be interfering. Something is.
Don't rule anything out.

[Wild Willy]

Wait. That was stupid. I already figured out there's a problem on the web site.
Unblocking things won't correct that. Oops.

[James Cognito]

Yup, Ive already checked my browser installed extensions, but disabling them did not work as well..

Hmm.. I will try to use Yt-dl or something then..

Even JDownloader can't download this because it says that is not compatible with 128 AES decryptor. Just it cannot decrypt it, so maybe JD is a step forward to download a file.

[Wild Willy]

JD kinda-sorta confirms what I discovered, The item that is missing is identified by
ffprobe as a key file. Why do you need a key file? To do some decrypting. It sounds
like JD gives a slightly more informative error message than VDH. VDH just says 404 Not
Found without identifying what exactly isn't found. At least JD gives a message pointing
vaguely to where the problem lies. The information from ffprobe is very specific & shows
exactly what the problem is.

The content is encrypted & you need a key to decrypt it. The key is in the file that
ffprobe is complaining about with the 404 Not Found error. I'd be interested to hear
what your results are with YT-dl. I would expect it will fail as well. The problem here
is not in the download tool. The problem is on the web site. The only open question is
whether it is intentional.

The player on the page must be getting the decryption key from somewhere. If we can find
out where, there might be a chance that we could edit the master manifest & substitute
something in for the missing file. But that is likely to be a bit tricky because the
URLs in the master manifest I looked at were partial URLs. Fixing the master manifest
would mean copying it to your system & editing it. You would have to supply the missing
part of the partial URLs. That's actually pretty easy. Meanwhile, since you would have
copied the decryption key file to your system as well, you would have to change the
reference to that file in the master manifest, which is a URL, to a file specification to
where you put the key file on your system. If you (or anybody) can ferret out the key
file, we might be in business here. I imagine that file is listed in the Network Monitor
somewhere. I don't know how to look for it. We can't use the name in the ffprobe
reports. We know the key file is not found under that name. But I haven't tried to
figure out how a key file is identified in the Network Monitor. Maybe it has the string
"key" in its name. I don't even know what the contents of a key file look like. It's
probably a string of unintelligible gibberish characters, but I'm just guessing.

But this would be a lot of work to get this video. And would our technique work on other
content on this site? If we're lucky, it would. Or maybe this particular video is an
anomaly on their site & other content works just fine. What is your experience with
other content on this site?

[Wild Willy]

Your site was apparently down for a couple of days. But it's back up now. As I
suspected, the key file appears in the Network Monitor. It shows up as originating from
site keys.dacast.com with a type of pgp-keys. It's a small file, just 24 characters. As
I predicted, it's just a bunch of gibberish. But I saved it as a file on my system. I
then had to save the master manifest as well as 2 stream manifests on my system. The 2
stream manifests I saved were for the audio track & for the video track. There were
references to 3 video stream manifests in the master manifest. I removed 2 of them,
keeping only the one that was of the highest resolution, which was only 960x540. I had
to change the URLs in the master manifest to refer to the stream manifest files on my
system. I then had to repair the 2 stream manifests. All the references to chunks were
partial URLs. I had to do a global find/replace in my text editor to turn them all into
full URLs. That took a couple of tries before I got it right. Each of the stream
manifests referred to the key file so I had to replace the URL there with a file
specification on my system. By trial & error I finally corrected the file specification
to M:\\VDH Testing\\etc. It turns out ffmpeg, being written by Linux geeks, doesn't like
the standard Windows file naming convention that uses \ everywhere. I had to escape each
\ as \\. And that took me a few passes through everything before I got that all
corrected. But in the end, ffprobe ended up telling me, "Error when loading first
segment." I don't know what to do at this stage. It's possible some of the URLs I was
working with simply timed out because I was taking too long to wade through all the
errors I was making. And even if I had managed to get a result that would have allowed
me to download this with ffmpeg, I still say it's too much work. Plus you would have to
hand-craft a solution for each case. I say this site has changed the way they do things
within the past 6 weeks or so & they are now quite effective at thwarting download
software.

I'm still curious to know how you got on with YT-dl. And I still want to know what you
have found with other content on this site.

[James Cognito]

Hey.

Sorry, but I did not have time to look here, so much work...

Generally there's no difference at all.

Same problem with YT-dl - it shows 404.

I see You've wrote step by step what exactly happens in each element. Wow..

I've tested YT-dl both on Win7 and Linux. Same error - 404.

In YT-dl there is a clear message saying that it (probably) couldn't find the key.

JD still says that it is a 128bit crypto and it cannot do anything with that ; [

The screen above is from Linux as You can see.

On Windows Ive also tested a Youtube-dl (the old "abandoned" version), but none of the were able to download videos from PL1.

It seems they are using a strong key, or maybe there is no such key to make any downloads possible, yet.

Maybe there is an alternative to download those files, except for the option to record the screen.

Maybe I should write an issue on Yt-dl's github to give them any information about the problem.

[Wild Willy]

I don't think reporting this on the discussion forum of YT-dl or JD will be any help.
The problem appears to be that the web site has purposely posted their content with an
error in it. It's not about how many bits of encryption are involved. Their manifests
refer to a key file using a file name that apparently does not exist. I found their key
file. It's not in the file whose name is used in their manifests. This seems to me like
some kind of intentional way of defeating downloader software. It would have been easier
if they had just used DRM instead. You need to give up here. You are not going to get
this content downloaded. That's all there is to it. Screen recording is your only
option now. It used to work. Now it doesn't. They changed the way they operate. We
can't do anything about that.

[James Cognito]

What about If Itried to use some of previous VDH versions in my browser instead ?

[Wild Willy]

I can't even speculate what difference that would make. Understand that I am just
another user, like you. I don't have access to the source code of VDH, and I probably
wouldn't understand what I was looking at anyway. I have no idea what an older version
would do. You can try it & report back your results. My prediction is that more recent
past versions would have the same problem as the current one, and older versions might
not work at all. But that's a prediction based on nothing concrete. Try it & tell us
all what results you get.