Green line and poor JPEGs quality problem

[Jhonmicky]

Hello everyone,,,
i'm new here so excuse me if i post in wrong place

i like using avidemux to make gifs, and the video is from the screen recording i use from quicktime, Mac Lion.
the dimensions of the video varies, and the thing is that sometimes there is a green/yellow line at the bottom of the video, and i noticed that each time there are green lines, the JPEG quality really drops so i have to save the frames one by one by saving as BMP images.

is there any solution for this? i've read a thread about green line before, but i don't understand the solution since i'm not really good with programs and stuff, so please kindly explain it in a language that is easy to understand 

thank you....

[eumagga0x2a]

the video is from the screen recording i use from quicktime, Mac Lion.

But what version of Avidemux on which macOS version are you running? It was reported here that current Avidemux builds were not backward compatible with macOS El Capitan, so I doubt that they would run on even older versions. Only Avidemux 2.7.2 (the last release for macOS) and later versions are supported, any fixes can go by the very nature of development process only into the latest nightly builds and future releases.

Bad quality video out of the MJPEG encoder was fixed over a year ago. Green lines at the bottom of video display with some video output drivers may happen when the video dimensions are not a multiple of 16 (which also massively worsens compressibility).