[FFmpeg-user] how to concate two wmv files ?

[Bob]

On Monday 15 February 2016 08:03 PM, Jim Worrall wrote:
>> On 2016 Feb 15, at 11:59 AM, G Alexander <glen_alexndr at hotmail.com> wrote:
>>
>> what is this homework? this post is from someone who is clueless about video.
>>
>> unless the two wmv’s have the same bitrate, fps, etc and audio properties etc you cannot “concatenate” them and have decent output as ffmpeg will use defaults and result in a crap low bitrate output.  you have to convert each to a common format then map the input streams into an output stream.
> So why don’t you provide a better answer?  Why the hostility?  Obviously we know nothing about the files other than that they are wmv.  I was encouraging the poster to provide a command line and output that would reveal more information.
>
>


Hello All,

Thanks for your valuable responses. I have checked the two .wmv files 
with ffprobe and find following

```
ffprobe Bas2_201508292100_201508292130.wmv

[wmv3 @ 0x15c1720] Extra data: 8 bits left, value: 0
Input #0, asf, from 'Bas2_201508292100_201508292130.wmv':
   Metadata:
     WMFSDKNeeded    : 0.0.0.0000
     WMFSDKVersion   : 11.0.5705.5043
     IsVBR           : 0
   Duration: 00:30:08.80, start: 0.000000, bitrate: 421 kb/s
     Stream #0:0(eng): Audio: wmav2 (a[1][0][0] / 0x0161), 32000 Hz, 2 
channels, fltp, 32 kb/s
     Stream #0:1(eng): Video: wmv3 (Main) (WMV3 / 0x33564D57), yuv420p, 
720x576, 407 kb/s, 25 tbr, 1k tbn, 1k tbc
[wmv3 @ 0x15c1720] Extra data: 8 bits left, value: 0

```

and

```
  ffprobe Bas2_201508292130_201508292200.wmv

[wmv3 @ 0x2650720] Extra data: 8 bits left, value: 0
Input #0, asf, from 'Bas2_201508292130_201508292200.wmv':
   Metadata:
     WMFSDKNeeded    : 0.0.0.0000
     WMFSDKVersion   : 11.0.5705.5043
     IsVBR           : 0
   Duration: 00:30:07.72, start: 0.000000, bitrate: 422 kb/s
     Stream #0:0(eng): Audio: wmav2 (a[1][0][0] / 0x0161), 32000 Hz, 2 
channels, fltp, 32 kb/s
     Stream #0:1(eng): Video: wmv3 (Main) (WMV3 / 0x33564D57), yuv420p, 
720x576, 407 kb/s, 25 tbr, 1k tbn, 1k tbc
[wmv3 @ 0x2650720] Extra data: 8 bits left, value: 0

````

I tried to join these two file with

```
ffmpeg -i 
"concat:Bas2_201508292100_201508292130.wmv|Bas2_201508292130_201508292200.wmv" 
-f wmv -c copy output.wmv

```

But the output.wmv contains only the first file. Further google 
searching suggest ffmpeg can't join .wmv files.  What can be done here 
then ?

Thanks and regards,
Bob