Tiny video File sizes

[ednorton759]

I keep movies on the PC and have previously used Dr. Divx or other Divx utilities to convert from DVD etc sometimes I have used Freemake video converter and have been ok with the result. I have been doing this for sometime so I am not a TOTAL newbie but I confess I get a bit lost in the terminology.

Anyway...about a year ago I downloaded a new tv series where the show is 45 minutes in length and VERY HD quality and only 135MB to 150MB in size.
TV episodes I have done myself (After losing the commercials)are usually about 330MB in size with good but not GREAT HD quality. 1/2 the file size with better quality? Sign me up!

I have a utility called Media Info that tells you some details of a video file and it says this is an mkv HEVC file. The file description In the file name says " HDTV 720p x265 AAC. Recently I got Wondershare Converter Ultimate which has the option to convert to MKV x265 but whenever I try that the projected file size is the same as what I am converting from or even larger. Any idea how this incredibly small file size was achieved???

[manono]

...whenever I try that the projected file size is the same as what I am converting from or even larger. Any idea how this incredibly small file size was achieved???

By using a lower bitrate than you're using, or a higher CRF. Since I don't use anything Wondershare (nor should anyone else) I don't know how you might set the bitrate in it. They're probably also using AviSynth to filter the video to make it more compressible.

[KarMa]

Any idea how this incredibly small file size was achieved???

They used a lower bitrate, or a higher CRF value.

file size = bitrate * running time

Xvid, Divx, x264, x265 can all achieve the same bitrate for most content, giving the same file size. But it just comes down to the quality they give for a given bitrate. x265 conforming to the newer HEVC standard does the best usually and is also the slowest. x264 does a bit worse but still good and much faster and more compatible. Slower presets on any of these codecs will usually give better results than the faster encoding presets. It's usually just a question of how much CPU time you are willing to put into a video. Also in x265 and x264, two pass and CRF give better results than one pass(abr)

In a nutshell you can have a fast encoding, a quality encoding, or a small file size. But you can only have two.

They're probably also using AviSynth to filter the video to make it more compressible.

x265 with the default tuning does a lot of denoising by itself.

[videobruger]

1/2 the file size with better quality? Sign me up!

Start with a good quality source.

[Aludin]

That's because x265 is way better than Divx like Divx was way better than Indeo. You've been living under a rock. Better codecs have been out for some time now.

[pandy]

It is not so difficult to reduce size by half and minimize quality loss (perceived) - for example dual pass can be beneficial as bitrate may be better allocated. Prefiltering may be used to improve compressibility (noise can't be compressed - remove noise and video automatically need less bits to deliver same quality), modern video codec usually provide lower bitrate with same quality as it use more advanced tools to compress video.