WMV file sizes

Imanuel

Video in MP4 format that is transmitted through VideoPad to WMV format becomes 40% smaller at approximately the same bitrate even without editing.
This is obvious to me because the WMV format is more economical although it doesn't work on all platforms like MP4.
What is not clear, why in the second pass of the same output video in WMV format through VideoPad to WMV itself at the same bitrate the file size again decreases significantly.
I learned that the size and quality of a video in a particular format depends solely on bitrate. And here, I'm facing two files both in the same format, bitrate and frame, but one is significantly smaller than the other.What's going on here? What magic touch does VideoPad has?
If BORATE is still active, I would love for him to answer. From my previous experience, his answers are clear, complete and educated on related topics.

Thanks

Imanuel

borate

Tested two mp4 to WMV exports. When the WMV bitrate was left at the 8192 default (considerably higher than the mp4s), file sizes increased, as expected.

If the bitrate was set to the same value as the original, then they decreased - as in your test.

However, the WMV-to_WMV second export did not change significantly...

For example, on a 2:20 file the original's bitrate of 33.65 was reduced to 24.78. The WMV-to-WMV pass was 21.14.

Don't know why, but if more info surfaces it will be added here.

Upload a file that has the behavior you described and someone will check it out.

Use a free server, such as Google Drive or MS OneDrive, get a shared (public) link, copy the link and paste it here or to me in a Private Message via the mail envelope in the top-right corner of this forum. When using Google Drive, if necessary change "restricted" to "anyone with link can view."

Imanuel

Hi Borate. thanks for yourd answer. This is not a single file but a series of large files. In some of them second reduce was smaller, about 20%. In your example its also happened. Unfortunately I can't send the files both because they are too large (over 1 G 8000kbps) and also because they, how to say it, are private. I will do more experiments on small neutral files, I will also try to run them in a third - and report the result.

In any case, am I right that two files of the same format with the same bitrate and the same frame must be the same size?

borate

One would think so, but don't quote me.

A test of the Windows WMV wildlife :30 video exported to WMV at its 6183kbps original bitrate took the filesize from about 25MB down to 15MB on the first pass. Same file, same format, same frame and bitrate. But obviously, some processing was applied on this pass, which reduced its size.

But that file size remained unchanged in subsequent exports where the most recent export was repeatedly exported again at the same settings.

Sharing can be private, via a personal message. No one else will see the file. Click the envelope at the top-right of this forum.

Imanuel

OK. If so, your claim, that there is no such thing and the files should indeed be the same size.i understand that the burden of proof is on me. I will do the experiment I promised within a few days. Maybe it's only in the big files and maybe it's only in my version. To be heard.

borate

Please check for a Personal Message that explains this issue in more detail.

Imanuel

I read it. You helped me a lot, as always. And as always I came out with a lot of insights and knowledge from our conversation. Thank you. Imanuel