Selur's Little Message Board

Hi!

I have a lot of DVDs that take up a lot of space, so I'm trying to find a way to make them smaller in size. I'd wish to have them smaller in size without losing quality.

In this case, it's about 20 min length 720x520px videos that are about 1GB when I convert them to MKV (using MakeMKV). From what I've heard and read, MKV should be like a direct DVD video rip, and therefore lossless. But it takes as much space as the original VOB files inside the DVD's VIDEO_TS folder. I wonder if it's really necessary for these video files to take this amount of space if you don't want any quality loss.

I've tried different tools to convert them to MP4, because those files usually take up less space. But so far, they all had reduced video quality. Maybe Hybrid could make a change, but that programme is pretty advanced so I wouldn't really know what settings to go with. However, I first need to know if it's possible to get these DVDs ripped in a smaller size without quality loss. Maybe MP4 is like JPG for images or MP3 for audio files, which always cause a reduce in quality. On the other hand, maybe there exist "smart" video file formats that compress the video or something to make it smaller.


Some help with this would be nice! Thanks in advance. Please, read the 'Infos needed to fix&reproduce bugs,..'-sticky before you post about a problem.

Quote: I'd wish to have them smaller in size without losing quality.

Not possible with any format I know of. All current formats like H.264, H.265, AV-1, VP9 are all will either:
a. be lossless and produce huge files
or
b. be lossy
Your best bet is get something where you don't see the difference.
-> try for example H.264 with x264 as encoder with a crf of 16 or H.265 with x265 as encoder and crf 16.

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To answer you title: 'How do I keep DVD rips small in size?'
a. you filter your input to remove unneeded details, noise and artifacts (yes, DVDs are full of compression artifacts).
b. you recompress into a format which produces a smaller file size that produces for you perceivable quality loss.
No there are no clever/smart/magic ways to do this always perfectly.

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also: mkv is a container format like vob/mpeg/ts/m2ts/mp4
MakeMKV is a multiplexer which repacks for example DVDs or Blu-rays (or more precise parts of them) into mkv.

H.264, H.265 are MPEG video compression formats.
mp3 and aac are MPEG audio compression formats.

Quote:On the other hand, maybe there exist "smart" video file formats that compress the video or something to make it smaller.

I know of no lossless transcoder from MPEG-2 (which is the video format inside a vob container on a DVD) to any format that compresses better.

Quote:Maybe Hybrid could make a change, but that programme is pretty advanced so I wouldn't really know what settings to go with.

Yes, Hybrid is probably not the right tool for you. StaxRip, Handbrake, MeGUI, VidCoder,.. are probably more suited for you.
(You are welcome to try, but Hybrid in general is aimed for more advanced users who seek more control and screws to turn, but know what they are doing. )

Cu Selur

(21.08.2018, 19:36)DannyHicks Wrote: [ -> ]Hi!

I have a lot of DVDs that take up a lot of space, so I'm trying to find a way to make them smaller in size. I'd wish to have them smaller in size without losing quality.

You can encode it with x264, or better yet, x265, and probably get a much smaller file without any loss in perceived quality. That is, you probably won't notice any quality loss, unless you strain your eyes and look for it. However, you have to know something about the encoding options to be able to achieve that. If you are new to encoding (I'm presuming!), try a CRF encode. Filtering out noise and compression artifacts would greatly help, as selur mentioned.


@selur : Not to hijack the thread, but since you mentioned the fact that DVDs usually have a lot of compression artifacts, could you mention some of the common ones, and which vaporsynth or x265 options to use to remove them? I have a few DVDs of old TV shows from the 70s and 80s, and they are choke full of bad artifacts - but I don't know what kind of artifacts they are. Deblocking, debanding, derainbow, denoising....what would you expect would help? I know it depends on the source, but generally what are the most common filters to make that sort of DVD videos better?

(07.09.2018, 09:13)Toothache Wrote: [ -> ]

(21.08.2018, 19:36)DannyHicks Wrote: [ -> ]Hi!

I have a lot of DVDs that take up a lot of space, so I'm trying to find a way to make them smaller in size. I'd wish to have them smaller in size without losing quality.

You can encode it with x264, or better yet, x265, and probably get a much smaller file without any loss in perceived quality. That is, you probably won't notice any quality loss, unless you strain your eyes and look for it. However, you have to know something about the encoding options to be able to achieve that. If you are new to encoding (I'm presuming!), try a CRF encode. Filtering out noise and compression artifacts would greatly help, as selur mentioned.

It's worth saying this again, to be clear.


The thing is that the modern encoders, x264 and more recently x265, can encode videos with little or no perceived reduction in quality.

For DVDs I have used a crf of 20 with x264 and had very good results, reducing the crf further often won't get perceivable improvement so lowering it a bit, say 18, will make the encode larger so the reduction in size will be less but the quality should be about the best you can get. You need to experiment a bit before you chose.

While the quality of DVDs is not nearly as good as Blu-Ray discs that is what's been produced at the time. There can often be some noise or other artefacts but trying to eliminate them can easily make the video look worse. Be very careful with noise reduction, it shouldn't ever be needed and if used at all a low setting is often better.

Beware that artefacts in the source video are often increased by re-encoding them (I say re-encode because they too are a result of encoding in the first place), that's just the way it is.

While the x265 encoder provides better quality and uses less space there's the problem of playback.
While it's "better" decoding them for playback takes more resources and there's the question of whether your playback devices are even capable of playing them.

Most common artifacts are:

• macro blocking: you counter that with a deblocker, settings and filter
  
• ringing: for this you use de-ringer
  
• banding: for this you can use a debanding filter and ideally encode to 10bit
  
• aliasing: for this you might want to try a anti aliasing filter, be careful with these since they are often aiming for cartoon content
  

Depending on your source and your liking, you might also want to add a light degrain filter or which is often my preference use x265s/x264s internal noise filter.

If your source is interlaced you should deinterlace and if you source is telecined you should use an ivtc method.

Also remember: try to keep the filtering minimal, nearly all filters destroy information and most of the time its a 'give and take' so don't blindly filter.
Everyone you things that he found a perfect filter combination which is correct for all input is a fool.

Cu Selur

^^
Thanks, I guess I need to look into the deringing and debanding a bit more.