adding watermark to .mkv with megui without reencode

[sepano]

hello friends
i tried this script for adding watermark to .mkv using megui and avisynth:

LoadPlugin("C:\Program Files\AviSynth 2.5\plugins\remapframes_25_dll_20050826\RemapFrames.dll")
a1=DirectShowSource("clip.mkv",fps=23.98)
a2=ImageSource("logo.png",pixel_type="RGB32")
a3=Overlay(a1,a2,mask=a2.ShowAlpha())
ReplaceFramesSimple(a1, a3, mappings="[0 299][5999 6299]")

but it encodes the video.
do you have any idea.
is there any thing wrong?
i use ovelay and it shuodn't reencode the video

[Baldrick]

You must reencode. Or else must you add a switchable subtitle with mkvtoolnix.

[sepano]

subtitles can be swiched off by users

it is not the solution

i want to add watermark to mkv using overlay .

isn't it true that overlay shoud attach to video without re encoding?

[Gavino]

isn't it true that overlay shoud attach to video without re encoding?

No. As manono said the last time you asked the same question (only 3 days ago!), using Avisynth to create a new video always requires re-encoding.

[sepano]

i'm so sorry
i didn't mentiond the monono's answer.


just another little question:

is there any tools like megui that can use gpu for faster encoding??