How to encode High Quality MKV to (SD) AVI?

[whatever911]

Let's say that i have a HQ MKV file that is about 250MB and it's only 30-min in length, and i want to convert it to AVI but reduced in size (down to about 175MB). How do i go about doing this? If you've downloaded anime in (SD) AVI, you'd know that each episode's file size is about 175MB for a half-hour length. Could someone please guide me through this conversion? Thanks!

[redwudz]

One way: https://forum.videohelp.com/topic241422.html

[whatever911]

I read Baldrick's guide long time ago and it's a good guide; however, his guide only covers the basics. In my case, the MKV file has softsubs in .ass format and i want to convert to AVI in hardsubbed. Plus, this video MKV file can't be opened in VirtueDub, and this error happens only when the video file has H264 codec in it. That's why i use MKVExtract to extract the video, subs, and audio; but sometimes, only the subs and audio are extractable. I don't know what to do. Please help me. Thanks.

[poisondeathray]

You can use avidemux to convert mkv => hardsub xvid .avi (using .ass)

[whatever911]

Thanks for the reply.

Actually, i had also tried that, but if you use AviDemux to convert from MKV to AVI, the quality will be reduced down to about 70% of the original, which is not really good. That's why i wonder how the anime fansubs such as DB for instance could produce such high quality videos.

Do you ever notice that at the end of every episode that is subbed by a fansub, there are some weird numbers? (ex: [DB]​_Pokemon​_Diamond​_And​_Pearl​_008​_[CB66A8F3].​avi) => see the numbers: CB66A8F3??

[poisondeathray]

You can expect a huge reduction in quality.

You are probably using h264 in the .mkv and reducing the bitrate by 30%, and on top of that using converting to xvid => a less efficient compression method than h264. Furthermore you are encoding from a lossy source, not the original source.

If you started from the original blu-ray (preferable) source, or at least the DVD, you might get good results

You might be able to reduce your quality loss by using better xvid settings (the defaults aren't the best)

You would get much better results by not using xvid/.avi, and using h264 instead, because xvid has no deblocking, and at low bitrates it looks very poor.

[SatStorm]

What you wish to do is possible, but it needs TIME. Lot's off.

The workaround that I do to succeed it, goes like this:
1- First you load your source to avidemux and you add the subs you wish to hardsub. You save the new file to Mjpeg with 90 or more quality.

2 - The new huge file, that now includes the subs, you open it to Virtualdub. Then you add there some filters:
The first is NeatVideo. You must select the "filter and sharpen" preset and tick the "Smooth Edges" option.
The second is MSU Smart Sharpen Filter. You sharp "overall and boarders"
Then, you use MSU Denoising Filter 2.5 at "carefull" setting. That helps on compression.

Now you save to XviD doing the usual things. 2 Pass VBR for lower bitrates may help you. Remember to set XviD to "cartoon mode".

[guns1inger]

I use Xvid4PSP to do this with HQ MP4 files. I resize to 720 width, use the Limited Sharp Faster filter and the AVI (Hardware) settings. The quality is very good in the resulting file (assuming you give it enough bandwidth)

[whatever911]

@ poisondeathray: But fansubs don't have the DVD to rip from. Take Naruto Shippuuden for instance, new episode is aired on TV every week in Japan, and fansubs use the recorded RAWs to sub and encode to AVI. I'm also using the HD MKV Raws to encode to AVI using AviDemux, but the output isn't as good as theirs (the fansub's)

@ SatStorm: I think your method is the one that i'm looking for. But how is the output's quality compared to the original quality? What about the size? Could you give me an example in which you've encoded from MKV to AVI? (ex: file size, resolution, time needed to encode, etc...)

@ guns1inger: I'll try out Xvid4PSP as soon as i'm done with the final exams which are 3 days from now. It looks like a good program.

---------------

There's one more thing that i really want to know. People who work for anime fansubs in Quality Checking fields say that encodings take days and one minor mistake could cost them to redo the whole thing. Why is that? How could one episode that is only 25-min in length take days to encode? There must be a common program for encoding anime, right??

[guns1inger]

I doubt they take days to encode, however if they are encoding with a lot of tweaking and dividing the encoding settings section by section to get the highest quality from the available bitrate, it could take a while to set up. When movies are encoded by the studios every transition is hand tweaked to get the best quality encode that they can.

Having said that, most of the anime I have seen isn't any better than any other Divx/Xvid encode, and fan-subbers still haven't come to terms with safe areas and conversion for television viewing, so the idea that they have quality assurance people making sure that their subtitles hide in the overscan area is rather funny.

[poisondeathray]

@ poisondeathray: But fansubs don't have the DVD to rip from. Take Naruto Shippuuden for instance, new episode is aired on TV every week in Japan, and fansubs use the recorded RAWs to sub and encode to AVI. I'm also using the HD MKV Raws to encode to AVI using AviDemux, but the output isn't as good as theirs (the fansub's)

But your .mkv is not a raw file. How do I know this? A raw uncompressed HD 1/2 hour capture would be way over 100GB, not 250MB. Are you saying they use the same compressed 250 .mkv to re-sub it? or the original HD capture? There is a big difference.

Your goal of re-encoding the 30 minute, 250MB .mkv (I'm willing to bet it's h264 video) do to a 175MB .avi will leave you ~675kb/s video bitrate (assuming 128kb/s mp3 audio). If you reduce the audio bitrate, you could increase the video bitrate by the same amount. Even though cartoons are highly compressible, ~675kb/s from a 2nd generation source won't give you very good quality - especially if you are using XviD.

Since you're going to do this anyway, make sure you change the VHQ mode to 4 or "wide search" (from 1 or "mode decision") in whatever program you are using to encode. This will be slower but the quality will improve

Also mjpeg isn't lossless. So converting to the intermediate step as per satstorm's instructions will cause you to lose more quality, unless you used something lossless like huffyuv instead of mjpeg.

It would be faster just to use avisynth and feed an .avs script into vdub. Gunslinger's idea of xvid4psp is probably the easiest and fastest because it autogenerates an .avs script for you, and it will use TextSub() for the .ssa subs. You might want to tweak some of the filters to optimize it (satstorm suggested some in vdub, but xvid4psp has similar built in ones, and you can just edit the .avs script manually to access all of them)

Good luck

[mail2tom]

If by "High Quality" you mean 720p, then try Any Video Converter (http://www.any-video-converter.com/products/for_video_free/). It's freeware and pretty fast. I know it will hard code .srt files into the video, but I haven't tried .mkv with .ass subtitles. Nothing lost if it doesn't meet your needs.

[SatStorm]

mjpeg might not be lossless but all the frames are full frames. And it is the most sane codec you can use, in the terms of filesize when you decompress mpeg 4.
Many filters compare close frames / fields to detect what is noise and what is video. Also, filtering the mosquito noise around hardsubbs, can reduce the average bitrate about 10%. MJPEG (and HuffyUV) sources works better with those filters than a direct mpeg 4 to mpeg 4 convertion.

Anyway, the faster and easier is not my goal. The best possible quality visually is (I repeat: visually). And from all the methods I used over the years, the one I suggest produce me the best quality at the smallest possible filesize. And no mosquito noise around the hard sub text too.

For faster, there are many programs out there.

Somehow, all this reminds me the analogue secam years... There were some secam to secam solutions, but it was far better to convert your secam source to pal, do your work there and convert again the signal to secam. Totally different technology of course in this example, but still the whole prossess reminds me those years.

Regarding the time is needed, since I do some fansubbing myself, I needed for the workaround I suggest about 16 hours for a 2.20 hour movie on my C2D E6600. The result xvid file was 1gb and visually looked better the source I had. I didn't use 2 pass VBR.

[whatever911]

Thanks for helping guys. Once the finals are over, i'll get right on to all of your methods of encoding and definitely write back some feedbacks or questions that i might have. Thanks again. Y'all been great help xD