MKV to AVI Video Bitrate Setting

[gonwk]

Hi folks,

I wonder if someone can tell me what would be a "Rule of Thumb" for Video Bitrate Setting to convert from a MKV Original to AVI!?!? BTW, the MKV file is a Kung Fu Action movie.

For example my Original MKV file has Video at 500Kbps ... so if I am using XMedia to convert it to AVI ... what would be the BEST setting for my output AVI Video Bitrate!?!? For example 2 times as big as MKV Vidoe Rate of 500Kbps or 1.5 times or what?

I persoanlly was DOUBLING the MKV Video Bitrate ... but I am not sure if I am doing an overkill!!!

Thanks,

G!

[Baldrick]

Use constant quantizer/quality if you don't need specific size. I think constant quality setting 2 or 3 is good for xvid mpeg4 video.

[jagabo]

MKV and AVI are simply boxes that contain video and audio that may be compressed (or not) with any of a number of codecs. Different codecs have different abilities to compress video. Different videos require different bitrates even using the same codec and the same settings. So there is no single bitrate that works best with all videos. If quality is more important to you than file size, use constant quality encoding. The final video will always have the quality (relative to the source -- ie, a bad source video won't get better) you specify, the bitrate will turn out whatever was necessary to achieve that quality. In Xvid it's called Target Quantizer encoding. In x264 it's called CRF (constant rate factor) encoding.

[MilesAhead]

When I create an .avi encoded with xvid, if the input looks good, then I try to use 1500 to 2200 kbit bit rate. If the input is .mkv or .mp4 I most often use Quick AVI Creator since xvid_encraw can do a good job in one pass mode using a high bit rate.

I add this to the xvid.presets file to get a one pass mode

[One Pass Mode]
xvid_encraw.exe -i "$video_input" -bitrate $video_bitrate -progress 1000 -avi "$video_output"

but you can use 2 pass. I just find if the input looks very good doubling the encoding time doesn't really add much to the quality. If you have a 50" HDTV then maybe you go for all you can get though.

edit: I tend to go by how the input video looks rather than numbers. You can have 8000 kbit DVD that looks like crap or a 5000 kbit DVD that was made from a BluRay source that looks great. If the input looks really good I try to use as many bits as I think justified in the xvid encode. Over 2400 kbit is pretty much overkill. For really glossy good looking input 1800 - 2200 is usually optimal for xvid one pass.

edit2: the other consideration, if low bit rate .mkv videos that you watch look very good then it may be simpler to get a set top box that can play them as they are. I've seen some 480P .mkv at low bit rate that look very good. I just play them on my WD set top box as is.

[jagabo]

Look at the three videos in this post:

https://forum.videohelp.com/threads/295672-A-problem-for-video-experts?p=1811057&viewfu...=1#post1811057

Then decide what the "best" bitrate is for all videos.

[MilesAhead]

Look at the three videos in this post:

https://forum.videohelp.com/threads/295672-A-problem-for-video-experts?p=1811057&viewfu...=1#post1811057

Then decide what the "best" bitrate is for all videos.

It sounds like a homework assignment. Sorry but I didn't enroll in your school.

[gonwk]

Hi folks,

Thanks Baldrick, Jagabo, and Miles for your responses. Appreciate the Help as always!

G!