Mp4 Size Matters????

[cetrax]

I was wondering if anybody could tell me how much they usually compress their video to?

I was thinking if I have a 5gb Vob movie file and I convert it to a 2.5gb mp4 movie if the quality would still be good enough to watch on a 47" lcd hdtv.

Can you please share your experiences and wisdom with me??

[Selur]

Assuming you are moving from MPEG-2 to MPEG-4 video with this, halving the bit rate should be possible without loosing any perceivable quality. (using i.e. x264 and a crf of 16 or 18 is normally near lossless for most people)

[Slipster]

As well as your personal susceptibility to artifacts, it also depends heavily upon the encoding strategy being used and the encoder profile being used, although the 2:1 figure above should be enough to almost guarantee perceptual transparency most of the time with CRF encoding. The only potential problem with CRF encoding is that you won't have any idea what the compression ratio will be as it varies depending upon the complexity of the source material.

I'm going closer to 4.5:1 here (so around 1GB per SD movie with 2-pass encoding) with the aid of psychovisual optimisation tweaks amongst others for viewing on a 42" LCD/LED panel. There is an easily discernible difference in fine-grain detail with this level of compression with grainy source material, but it's otherwise still a joy to watch with none of the block noise or mosquito noise artifacting being visible that are so often associated with bitrate starvation.

I'd say probably somewhere between 2:1 and 5:1 depending upon how fussy you are, but the ultimate test is your own eyes as only you know what is "good enough" for you. Others can only ever give you a ballpark figure as they don't have your eyes or your viewing equipment.

[Hoser Rob]

I suspect the 5Gb vob is a number of vob's ... I'd try importing just one of them into handbrake (or whatever you're using, but for ease of use combined with power handbrake is hard to beat). Use different crf (they call it constant quality) settings, starting at 16, which gives better quality and larger files, and encode the clip several times. See for yourself what you like.

Make sure you use high profile. You cannot get decent quality without it no matter how much you tweak it otherwise. Standard (default) profile is fine for mobiles but not a real screen.

[cetrax]

Thanks so much. I am using handbrake.(First time user). And am just feeling my way around the program.

[marioval]

I use DVDfab to "rip" (as they call it) my DVD's to MP4 with AC3 in 1 pass mode and keep the resolution 720x. My own personal rule (which I made up arbitrarily) is movies around 1 1/2 hours 1GB, around 2 hour movie 1.3GB, around 2 1/2 hour movie 1.8GB. This works for me.

[cetrax]

I suspect the 5Gb vob is a number of vob's ... I'd try importing just one of them into handbrake (or whatever you're using, but for ease of use combined with power handbrake is hard to beat). Use different crf (they call it constant quality) settings, starting at 16, which gives better quality and larger files, and encode the clip several times. See for yourself what you like.

Make sure you use high profile. You cannot get decent quality without it no matter how much you tweak it otherwise. Standard (default) profile is fine for mobiles but not a real screen.

Quick question. When using Handbrake. I select High Profile and crf of 17.

Should I also click the Web Optizimied box?

[Hoser Rob]

I've never used "web optimized". I suspect it's intended to create youtube compatible mp4 out of the box. Until I want to upload to youtube I'm going to leave it unchecked.

Re dvdfab ... sorry, but while I highly recommend their free decrypter/ripper, I simply do not consider their encoder in any way comparable to handbrake. Except badly. 1 pass mode (non crf) is no damn good.