Understanding video quality

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avi

avi

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I have 15" screen laptop which has 1080p Full HD screen [Dell XPS L501x]. I have built in 2.1 speakers.

In torrents there are many versions of 1080p videos available but how to choose which one will be best for me ? 15GB ones will do no good for me. And they come with 7.1 audio channel which one also not useful for me.

Then there are small sized like 1.5-2GB 1080p rips in those I can easily see quality difference sometimes.

So what should be maximum video bit rate above which has no effect in my experience ?
 
@avi

With a 15" screen you are too much concerned. Even a 720p will look very good. Its not like it is a 55" big a$$ TV that you have.
And you seriously are thinking about downloading 15GB on one single movie ? Unless you have some super duper fast connection.
 
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1080p Full HD screen i.e at 1920x1080 resolution

Even 720p[1280x720] works fine as raksrules suggest

Then there are small sized like 1.5-2GB 1080p rips in those I can easily see quality difference sometimes.
Click to expand...

can you explain?..
 
2GB DVD9, Blu-ray will work, try to go for 5.1 DTS or Dolby :)

Who knows in future, you might buy a 65-inch LCD with Sony 7.1 channel home theater system..

Start making your movie collection now, and when you had enough tell me, will buy you a external HDD, copy all data in it and courier me.... X::X :unsure:
 
the difference lies in the compression used.
The smaller rips have low bit-rate audio and the video is compressed to such an extent that visual artifacts are quite prominent.

Contrary to other's views the smaller rips look worse on the 15" screen than on a large TV as the viewing distance is much lesser,so all the video's defects are more prominent.
 
The most obvious difference would be in:
Dark (night) scene and fast-moving scenes.

If you're planning to watch some action movie, go for a big print . Usually(although not necessarily) they'll be of better quality.
If you're planning to watch say a more drama oriented movie, like the man of earth, even a DVD print would do.

Depending on the compression quality, there's always a quality loss from the 40+ rips.

As an analogy, for audio books even 64 kbps is good enough , but you need at least 192kbps for decent music experience. Depending on the equipment and the person even 320kbps would seems less and FLAC becomes absolutely necessary It al depends on the nature of content, the equipment and the person. .
 
let me put this from the perspective of encoding movies.
to make a movie, you will need to show at least 24 photos in one second. which means 24fps.
now consider this, if you have an uncompressed movie; say from a video camera, it would be 24 bitmap files put in a sequence,
A mpg video is made by compressing each bmp image frame to a jpg image frame. decent quality but requires some cpu/gpu processing power and some loss of quality.
when you talk about the newer movie codecs; they do more than converting each frame to a jpg. there would be some key frames(p frames) and some delta frames (b frames) each delta frame would only have the changed pixels from w.r.t p frames converted to jpg images. (this is why you will see strange images until the scene change on some badly encoded movies when you seek to random location)
the latest H264 codecs do even more than that to compress the movie further, they apply lot of matrix transformations to decrease movie size and the lost information is guessed using matrix equations (some thing like franhaufer transformations which I never understood.)
So when someone says that the movie is encoded to 800kbps, it means that the codec uses a max of 800kb per scond to encode the frames, means lots of artifacts compared to higher bitrate movies at that particular resolution.
Now coming to your query:
128kbps audio for 2hr movie takes in the order of ~100mb. a dvd quality of sound (ac3 6 ch at 448kbps) takes around ~600mb. DTS takes around 1.3GB. so rest is the data for movie. Ideally a 2-3GB 720p looks as good as ~6GB 1080p movie with ac3 6ch sound. if you go below that, you will find artifacts at fast moving scenes, if you dont have powerful hardware, the VLC will skip frames to compensate the lack of decoding power hence jerky movie at car chases.
So... if you want to play movies like avatar at 12GB, you will need good graphics card to render and a fast hdd to read atleast 2-3mBps speed constantly without lags. (if you try to play from a thumb drive, it will be jerky)
on the other hand, if you have less powerful hardware, just stick with 720.
lastly, compressibilty for anime and 2d cartoons is very high(obviously) so their size is much smaller. PS: highly encoded ****ed rips= yify good encodes with good audio, public china hd, nlupper
 
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Check this Video bitrate. Bitrate indicates quality. You can go for a lower audio Bitrate file. Forget the DTS 5.1 rips.
 
dexBG said:
Check this Video bitrate. Bitrate indicates quality. You can go for a lower audio Bitrate file. Forget the DTS 5.1 rips.
Click to expand...

@op: don't listen to him :p buy a good usb headset with virtual surround and download movies with dts (watch @full volume); else whats the point of 1080p?
 
I watch movies on my 32 inch 1080p TV, but I still only go for the 2-3 GB in size 720p rips, as they are very good in quality. I don't need to download 1080p rips as most of the action/superhero movies I see in the hall, and personally I feel only they need to be viewed in the highest quality possible.

Less than 2GB 1080p rips also exist, but there is a lot of pixelization which I personally hate.
 
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