Cause of "Invalid File Name" Error?

[Henry]

Hi, 

I'm getting "Invalid file name" error on some videos but not others. I can't seem to pick up a pattern on what causes this. What causes this error? and is there a workaround?

(I am using browser downloader. This is because when I use the companion app downloader videos often stop downloading early but show in my folder and then when I pick a point in the video timeline (while viewing the video) that is past the point at which the video stopped downloading the video just stops working.)

Many thanks! 

[mjs]

Instead of doing a quick download there is download which will give a dialogue to choose file name. Try giving your file a different name and

see if this works. Also if you have a video you see this problem on share it here for others to test.

--

A vdh user

[Henry]

Thanks for your reply. 

When I click on "Download", there is no dialogue to choose file name. The same process/error occurs.

[Henry]

Does the option to choose file name only work when using the companion app to download a video?

[Wild Willy]

Yes, the file selection dialog appears only when you use the CoApp.

I feel your pain about interrupted downloads. If you use Firefox as your download
processor, you at least have the option of using Firefox's own built in feature for
resuming a download from the point of failure. This is not available with the CoApp.
Sad but true. The reasons are quite technical. I don't pretend to grasp them. I
discussed the issue of resuming a failed download from the point of failure with Michel
in this forum a couple of years ago. The bottom line is he can't do it.

The mere existence of the CoApp is "new." I put that in quotation marks because it's
been a few years now that the CoApp has existed. But in previous versions of VDH, there
was no CoApp. There was a sea change when Mozilla introduced Firefox Quantum. That was
about 50 releases or more ago so it's not a recent event. But the Quantum architecture
removed permission for Firefox extensions to do a number of things, among them, access
the computer's file system. So when you tell VDH to use the browser as the download
processor, VDH does not have permission to hunt through your partitions & directories &
set a file name. The CoApp gets around this restriction by being a separate application
running in its own address space. It has full permission to do whatever it wants. I
think Mozilla was rather extreme in their decision to favor security over user
convenience when it comes to these things. But that's the reality of the situation.

In addition, there are certain types of download that can be performed only by the CoApp.
Two specific types I can think of are HLS streams, whether live or static files, and
YouTube. I always use the CoApp.

So your choice of download processor involves a number of tradeoffs. Only you can decide
which trades you are willing to make.

You can partially get around the restriction of no file selection dialog when Firefox is
your download processor, but it's a bit clumsy & tedious. You go into the Firefox
settings & change the default download directory. The setting is on the General tab
under the title Files and Applications. That still doesn't give you control over the
file name, only the destination directory.

You might say just because Firefox implemented a certain restriction doesn't mean other
browsers have to abide by them. True but . . . I don't use, never have used, Chrome or
Edge, the only other browsers besides Firefox supported by VDH. I'm not sure but I
believe Chrome implemented the same security restrictions for their extensions about the
same time Firefox did. Somebody with more knowledge could correct me on that. I have no
idea about Edge. In any case, rather than support 2 (or more) entirely different
architectures for the different browsers, Michel wisely chose to keep a single
architecture that works on all 3 browsers. So the CoApp is available to VDH on all 3
browsers.

The incorrect characters occur because VDH chooses a file name based on the HTML of the
page where the video is housed. HTML allows pretty much any characters at all. But
there are certain characters that are not permitted in file names by the operating
system. On Windows those characters are:

\ / : * ? " < > |

Note that apostrophe, comma, semicolon, exclamation point, & a number of other surprising
characters are valid. I don't know about Mac & Linux; I have no experience with those
systems. I'm sure your invalid file name is due to one or a few of these characters
occurring on the web page in a way that VDH picks them up for the file name. A word on
comma. I avoid that in file names. Some applications will fail to understand a file
name with a comma in it because comma is frequently used to separate parameters on
commands. So I say never use a comma in a file name, even if it is acceptable. Certain
special characters, like characters with accents which you will encounter in languages
like French, usually don't cause VDH any problems (although ffmpeg hates them). But some
users have reported problems with such languages as Chinese, Japanese, Arabic, & perhaps
a few others. Your system may accept those characters in file names because you are
using that language version. But VDH doesn't necessarily work properly in all such
cases. Best to download the file under a name that would not ruffle the feathers of an
English speaker & rename the file in your native language after the download completes.

[Henry]

Thanks for the insight/advice!