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-   -   Program to recursively find images and rename to "cover.jpg" (https://www.linuxquestions.org/questions/linux-software-2/program-to-recursively-find-images-and-rename-to-cover-jpg-937348/)

strungoutfan78 04-06-2012 02:55 AM

OK so I was looking into how I could possibly do this through the command line when I stumbled across a little program called eyeD3. I can use it to embed album art from the command line fairly easy. All I have to do first is remove all but one image from each directory in my Music folder hierarchy. Then I'll use find in conjunction with rename (the Debian perl rename) to rename any remaining images to cover.jpg (simply to have one standard name to feed to eyeD3 later). My problem now is, I can't get the syntax right on the perl regular expressions to rename any file ending in ".jpg" to "cover.jpg". This is as close as I've come:
Code:

find ~/Music -type f -iname "*.jpg" -exec rename 's/*.jpg/cover.jpg/' \;
Now I know this is wrong because apparently "." is the perl wildcard representing any character. What would I replace "*.jpg" with in the rename arguments to catch any file ending in ".jpg"?

strungoutfan78 04-06-2012 03:35 AM

I'm over-complicating things here. I just really got stuck trying to figure out how to use this damn rename command.
Code:

find . -name '*.jpg' -execdir mv {} cover.jpg \;
Works just fine. I'll post my results regarding eyeD3 tomorrow. Need sleep. Thanks everyone for your assistance with this tonight.

David the H. 04-06-2012 01:34 PM

Quote:

Originally Posted by catkin (Post 4644661)
It always used to be necessary but I routinely do not do so. IDK at what point it became unnecessary. From the GNU bash ref:
Code:

{}

              { list; }

    Placing a list of commands between curly braces causes the list to be executed in the current shell context. No subshell is created.

That does not define what happens when the list is empty.

Experimenting:
Code:

c@CW8:~$ echo {}
{}
c@CW8:~$ echo { echo foo > /dev/null }
[no output]

It would be nice to find a reference explaining that behaviour.


I'm fairly sure that what happening is simply that the exact string {} has no special meaning to the shell. Since it doesn't correspond to any defined syntax, it gets passed on as a literal value to the command. It's similar in this way to what happens when you have a globbing pattern that doesn't match anything.

I would personally still go ahead and quote it anyway, if only to not have bash waste a cycle attempting to parse it for meaning first.

As for this:
Code:

echo { echo foo > /dev/null }
Since the first word in the line is a command name, all the rest of the "words" are treated as arguments to that command. The {list;} syntax doesn't apply in this situation (although it's certainly checked for correspondence to brace expansion syntax first, a-la my first point above).

So all the elements are read as individual literal strings, except for > /dev/null, which is a redirection. It doesn't particularly matter where on a line you put redirections, other than that they get associated with the correct command; they are always evaluated and set up first, and removed from the command list before the rest of the line is processed. That's why you're getting no output.

To demonstrate, take out the redirect, and you get this:
Code:

$ echo { echo foo }
{ echo foo }


strungoutfan78 04-06-2012 03:41 PM

David,

Thanks for that explanation. Makes sense.

---------- Post added 04-06-12 at 01:42 PM ----------

David,

Thanks for that explanation. Makes sense.

strungoutfan78 04-06-2012 03:43 PM

Wow quick reply is now giving me problems as well as not being able to edit previous posts. Anyone else experiencing issues with these forums? May just be my version of chromium.

catkin 04-06-2012 10:45 PM

Quote:

Originally Posted by David the H. (Post 4646628)
As for this:
Code:

echo { echo foo > /dev/null }
Since the first word in the line is a command name, all the rest of the "words" are treated as arguments to that command. The {list;} syntax doesn't apply in this situation (although it's certainly checked for correspondence to brace expansion syntax first, a-la my first point above).

Thanks David :)

That makes sense (what was I thinking of :redface:?!). Another demonstration:
Code:

c@CW8:~$ echo { echo foo > /dev/null; }
bash: syntax error near unexpected token `}'


David the H. 04-07-2012 05:58 AM

I've found that a large part of scripting comprehension depends on having a clear understanding of just how the shell parses the line, and in what order. Knowing what gets done before what helps immensely in figuring out situations like this.

Code:

$ echo { echo foo > /dev/null; }
bash: syntax error near unexpected token `}'

For anyone who can't figure this one out, the unquoted ";" is viewed as a command terminator, so it's really trying to run two commands in sequence, "echo +arguments" and "}" But of course the "}" keyword can't be used as a command name.

But check this out:

Code:

$ alias '}'='echo "Hi"'

$ echo { echo foo > /dev/null; }
Hi


strungoutfan78 04-07-2012 11:40 PM

Great example. :hattip:

cascade9 04-08-2012 02:53 AM

Quote:

Originally Posted by strungoutfan78 (Post 4646016)
Well I did some more digging and found that it is only reading embedded art from the ID3 tags. That really blows. Guess I'll get started embedding one song at a time....:rolleyes:

W.T.F. What sort of crazy did that?

"I know, I'll have the artwork displayed from the ID3 tags.....even though the FOSS codecs I should be supporting dont use ID3 tags normally, and can often have problems with ID3 tags when they are used, and who cares about the extra space being used from having artwork embedded into the tags".

Im a little disgusted by that. But then again, what should I expect from something with virtually no documentation?

Sorry about my little rant that doesnt really help your problem.

BTW, if you really like album art give deadbeef a try. You wont get album art in popups, well, AFAIK anyway, I never really tired to do that. It might not be a media player that suits someone who likes XMMS2 (or maybe that is just caused by my 'omg its bloody winamp' reaction from the appearance), but its worth a look.

It can be a little tricky to get the album art displayed, so if you do try deadbeef I can give you directions for how to display album art.

strungoutfan78 04-09-2012 03:18 AM

Quote:

Originally Posted by cascade9:4647535
It might not be a media player that suits someone who likes XMMS2 (or maybe that is just caused by my 'omg its bloody winamp' reaction from the appearance), but its worth a look.

I'm fairly certain you're confusing XMMS2 with the original XMMS. XMMS2 is simply a daemon that runs in the background. It has no default gui although many exist. It can be used as a streaming client as well.

cascade9 04-10-2012 06:01 AM

Yes, I was. My mistake, my bad. ;)

My own fault, I made that mistake when I was looking for media players that would do what I wanted (album art, and a non-standard playlist format).

strungoutfan78 04-10-2012 02:48 PM

Its all good. :cool: I like not having to interact with my audio player. Just set it and forget it. I do like having the little pop-ups with a small album art thumbnail though. 99% of the time I just shuffle my entire collection while working. Don't care much for library management or playlists. Pcnanfm works fine for library management. XMMS2 and openbox with custom keybinds works great for me. I just like it to be as unobtrusive as possible.

273 04-10-2012 03:14 PM

Easytag will allow you to tag more than one file at a time -- I found out after going through a couple of albums that you need to tick the box to the right of the album art image to do so. I don't recall exactly when in the process to do this but you ought to be able to work it out now you know the secret of the tick box.

strungoutfan78 04-10-2012 04:04 PM

Quote:

Originally Posted by 273:4649584
Easytag will allow you to tag more than one file at a time -- I found out after going through a couple of albums that you need to tick the box to the right of the album art image to do so. I don't recall exactly when in the process to do this but you ought to be able to work it out now you know the secret of the tick box.

I'll have to check that out. Thanks for the tip.

strungoutfan78 04-10-2012 11:18 PM

OMG I didn't even see that tiny little check box on the side of the album art. I'm completely familiar with using it on all the rest of the fields, just didn't even see it there. So this thread was all for naught. :redface: I think I'm still going to continue with eyeD3 though, as I just like learning new ways to do things. Thanks to everyone who chimed in on this thread. Honestly it went on quite a bit longer than I thought it would. Marking solved. :D


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