China DOS Union

The copy command can copy files. The copy command can also combine multiple files into one.
I still don't understand a lot about combining files, so I hope everyone can give me some pointers!!
I used the copy command to combine two WMA music files, but they can't be played. My method was
copy 001.wma + 002.wma 003.wma, and the combined file 003.wma could not be played.
But when I used this method, copy 001.wma/b + 002.wma/b 003.wma, the file 003.wma made this way could be played, but what played was the file 001.wma. Likewise, if I use copy 002.wma/b + 001.wma/b 003.wma, what plays is 002.wma? So I want to ask everyone, when combining N files, does the final combined file X play the wma file right next to copy? I also have another question: since it's a combined file, is it possible to make them (N songs, where N depends on how many files are combined) play continuously? That is, after 001wma finishes, then play 002wma, and so on!!
Thank you, everyone, for giving me some pointers. I'm still just learning, so I hope you can tell me?

[ Last edited by raysea007 on 2008-1-14 at 08:49 PM ]

I've tried this method with mp3 and mpg, and it works (as long as the bitrate, sample rate, and channels are all the same).
But the wma file format is a bit more special. Its contents are not distributed evenly, so with a command like this
copy /b 1.wma+2.wma+3.wma new.wma the new file you get will be recognized as a file with a damaged end.



[ Last edited by bush on 2008-1-9 at 01:40 AM ]

Thanks. I'll go try it. Thank you, friend in the previous post.

Originally posted by bush at 2008-1-9 01:13 AM:
I've tried this method with mp3 and mpg, and it works (as long as the bitrate, sample rate, and channels are all the same).
But the wma file format is a bit more special. Its contents are not distributed evenly, so with a command like this
copy ...

I remember that COPY can combine files of the same type together, and I've also combined files of different types. For example, if an image and a text file are combined, the command copy 01.jpg/b + 02.txt/a 03.jpg makes 03.JPG display exactly the same as 01.JPG in an image viewer, but if you open 03.JPG in TXT, what you see is a bunch of garbled text. But if you hold down CTRL+END, you can see the contents of 02.TXT. In other words, we can use the image in 03.JPG to hide our private information, right? (I learned this on the forum.) I can also hide information by combining a WMA file and a TXT file, so I was wondering: what would happen if two MP3 files were put together? I've now also tried copy 01.mp3/b + 02.mp3/b 03.mp3 and copy 01.mp3 + 02.mp3 03.mp3, and both gave the same result: they couldn't be played, and when I tried to delete them with DEL, it even said access denied. With WMA files I can still play one of the songs. But when I switch to MP3, not even one song will play? Why is that?? Can you tell me how you managed to try it successfully? Thank you!! If I combine two text files, 01.TXT and 02.TXT, I can see the information from both text files in one text file. But what kind of result do MP3 and WMA files give? I want to know, and I've tried it too. Hope someone can point me in the right direction!!! Is it that image + image can't be combined, and audio/video files can't be combined with audio/video files either? Can anyone make them play continuously? Hehe, I'm a newbie, don't laugh at me.

[ Last edited by raysea007 on 2008-1-9 at 07:21 AM ]

Originally posted by bush at 2008-1-9 03:24 PM:

This question involves the issue of file header formats. Plain text of course doesn't have any special format. Other audio, video, graphics, images, and formatted documents (such as WORD) are all stored in specific data formats. ...

Thank you very much!!:P:P:P:P:P
Now I understand.

If mp3 files have the same bitrate, they can be combined, and you can listen to two songs continuously.
WMA files with the same encoding can also be combined, but you can only hear one song. For example,
copy /b 1.wma+2.wma 3.wma only lets you hear 2.wma.

Originally posted by 635635635 at 2008-1-10 02:42 PM:
If mp3 files have the same bitrate, they can be combined, and you can listen to two songs continuously.
WMA files with the same encoding can also be combined, but you can only hear one song. For example,
copy /b 1.wma+2.wma 3.wma only lets you hear 2.wma.

How come what I hear is 1.wma? Why? That's strange.

[ Last edited by raysea007 on 2008-1-10 at 10:04 PM ]

Experts from all sides, I'm just a newbie. Lately I've become downright obsessed with DOS, and I've run into the same problem here too. I used copy/b 1.rmvb+2.rmvb 3.rmvb to combine two files, and I still couldn't open it. When I played it with Baofeng Media, the screen was completely black. Even after reading the explanations above from the big brothers, I still don't understand. So is there any way to successfully combine two or more video files with copy????

Originally posted by hong555hong at 2008-1-11 08:11 PM:
Experts from all sides, I'm just a newbie. Lately I've become downright obsessed with DOS, and I've run into the same problem here too. I used copy/b 1.rmvb+2.rmvb 3.rmvb to combine two files, and I still couldn' ...

Didn't post #5 and post #8 already say it? Files with the same bitrate can be combined, so the audio/video files we found must not have the same bitrate. I know the reason now, but I still haven't successfully combined them yet!:D:D:D:D:D

Originally posted by raysea007 at 2008-1-12 01:02 PM:

Didn't post #5 and post #8 already say it? Files with the same bitrate can be combined, so the audio/video files we found must not have the same bitrate. I know the reason now, but I still haven't successfully combined them yet!:D:D:D:D:D

A bump,

Expert indeed
Big bump

Learning

We've only been focusing on the copy command. If there are only a few files, using the copy command is better. If there are many, then generally the xcopy command is used. But I thought of a question. Since audio/video files are relatively large, in theory it should be better to use the xcopy command when combining them, so I tried the xcopy command. But I found a problem, please advise!!!!!

C:\Documents and Settings\Administrator>xcopy 01.wma + 02.wma 03.wma
Invalid number of parameters

C:\Documents and Settings\Administrator>xcopy /b 01.wma + 02.wma 03.wma
Invalid number of parameters

I thought maybe it was because I was combining too few files, so I added a few more, but the result was still the same, C:\Documents and Settings\Administrator>xcopy/b 01.wma + 02.wma +

03.wma +04.wma
+05.wma 06.wma
Invalid number of parameters
Who can explain? Thank you!!!!!!!!!!!

[ Last edited by raysea007 on 2008-1-14 at 11:28 AM ]