Why is quality better in quicktime?

[alimustafakhan]

Hi,

I ripped a DVD movie into .mkv using MakeMKV the movie came out to be around 7GB on MKV file. The quality was almost 100%, but size was something I was not comfortable with. So I used Handbrake to compress it into .m4v and played it in quicktime. Trying to find out loss in quality played the original 7GB mkv file in WMP and compressed 4.5GB file in QuickTime. The quality of movie in Quicktime looked better.

Why????

[jagabo]

MakeMKV simply remuxes the DVD video into an MKV file. The video in the MKV file is exactly the same as on the original DVD. Any differences you saw compared to the DVD were player related. Recompressing the video could only have reduced the video quality. So the differences there are player related too.

How did you compare the two videos? Did you play them side-by-side at the same time? What player(s) did you use?

[alimustafakhan]

I compared them on Quicktime (.m4v compressed file) and WMP (.mkv file). I compared them side by side on my Full HD 50in Plasma (half screen with Quicktime and half with WMP. I also got my wife to give opinion and she agreed that the compressed video on Quicktime looked better than the uncompressed video in WMP. Keeping the compression in mind I was looking forward to Quicktime giving a worse quality than WMP, but the case was opposite... that is they question why????

The only reason I can think of is that may be Quicktime is a better player than WMP.

Any other ideas?????

[Lawbringer]

There could be a number of reasons.

1. Handbrake may have compressed the video with a "Sharp" filter, which may make it *seem* "better", i.e. sharper and crisper.
2. Quicktime may be better at playing m4v files than WMP is at MKVs. Try both the MKV and the compressed m4v in VLC Player

"Better" is usually a matter of opinion and perception in the situation where you're dealing with compressed video.

[jagabo]

Quicktime Player is the worst video player in existence. Windows Media Player is the second worst. But here are some reasons why video would look different in the two players.

Quicktime uses Windows GDI for playing video, WMP uses DirectShow. GDI wasn't designed for video, it has no special provisions for handling it. DirectShow was desiged for video. Players that use it have access to special features of the graphics card that are designed for handling video and reducing CPU load. DirectShow has separate (from the Desktop) controls for things like brightness, contrast, color, deinterlacing, noise reduction, shaprness, etc. It's likely those are not adjusted properly on your computer. Go to the graphics cards setup applet and adjust the video settings.

This isn't an issue when using Quicktime and WMP at the same time, but when using two DirectShow based media players only one of them will get the Video Overlay feature of the graphics card. That means one will get all the special video features your graphics card supports. The other will end up using Windows GDI. Since Windows GDI and DirectShow have different controls for brightness, contrast, hue, saturation, etc. watching two videos side by side will usually show a very different looking picture -- even if they are playing the same file

Quicktime uses its own video decoders. WMP uses DirectShow installed decoders. Different decoders may display the same video differently. Some may include deblocking, deringing, and brightness/contrast/color filters etc.

You didn't say which codec you used for your Quicktime conversion, but part of all high compression codecs is noise reduction. You might think this is a good thing but it can lead to posterization artifacts an creepy-crawly artifacts in dark, smokey or foggy areas, or areas with smooth gradients.

[creamyhorror]

Quicktime Player is the worst video player in existence. Windows Media Player is the second worst. But here are some reasons why video would look different in the two players.

I've heard bad things about Quicktime's H.264 decoding (glitches, slow decoding) in the past, but could you be specific? How is QT bad for playback?

And what's so bad about WMP?

[jagabo]

Yes, in addition to the bad h.264 decoder it has all the problems I listed earlier. Limited container and codec support, no Video Overlay capability, CPU hog...

[alimustafakhan]

Could it be that M4V was developed for Quicktime and hence it has produces better results for m4v files????

[jagabo]

Could it be that M4V was developed for Quicktime and hence it has produces better results for m4v files????

Not likely. Post some samples.

[alimustafakhan]

I am attaching the 3.5GB file being played on QT and 7 GB file being played on WMP and MPC. I think what makes the difference in the picture is that in QT the picture looks brighter and hence clearer.

Any thoughts... Ali

[jagabo]

I should have been more clear -- I was asking for was small before and after video samples, not screen caps.

As I said earlier, you can't compare multiple videos playing side by side like that on the desktop. It's likely that one was using video overlay and the others were not. Video overlay has its own brightness, contrast, hue, saturation, scaling, and sharpness controls (separate from the corresponding desktop controls). Even if the players are playing the exact same video the displays will be different (unless the Desktop and Video Overlay are set exact the same).

[alimustafakhan]

Dear Jagabo,

Thanks for help, however I think that would require too much work for the answer to be worth. I think I am pretty happy with the compressed 3.5GB file too. Hence I would let it go... Sorry for all the trouble.

Best Regards... Ali

[jagabo]

Go to Catalyst Control Center and adjust the Avivo Video settings.