Older movies are blocky

[kis2005]

I've done a couple of older movies with 2.26 and they have been rather blocky, especially in the dark areas. Any setting suggestions or others to increase the quality...if posible?

[manono]

Hi-

Did you set a fixed horizontal size, thus limiting what AutoGK could do to improve the quality? And what was the compress test result percentage? It's in the log.

Older films are often difficult to compress because of all the noise and grain often found in those films. You may have to use the more fully featured Gordian Knot, which allows the use of filtering that will help the compression, but may or may not improve the picture. Sometimes your best bet is to lower the resolution, or raise the bitrate/filesize.

[kis2005]

I usually set a fixed resolution for WS and FS at 720 and 640 respectfully. I do this thinking that it will give me better quality...am I wrong to assume that? I've been converting my collection to AVI so I can use them on a media server, so I tend to give the videos more size since I'm not going to burn them to disk. I'll have to find the Comp test results, but the settings for Road To Rio and Bali were 1/4 DVD fixed at 640 with 192 CBR. Other then the Audio being larger then I may need (still trial and error) I looked at the Sharp Matrix setting thinking that it might improve things. I'm not very familuar with Gordian Knot, but I'll will be if I need to be. Any suggestions are welcomed.

[manono]

Hi-

Yes, I would expect the compress test result to be pretty low if you're getting blocking at 1/4 DVD. Your theory about higher resolution being better is correct up to a point. You also have to allow a large enough file size. Forcing the sharp resize will make things worse. You might post the entire log if you still have it for one of the movies.

Do you want to see the films look good? Set up AutoGK for 65% Target Quality at 640*xxx fixed horizontal resolution. It'll run only one pass, so it won't take all that long. Don't be shocked by the final file size. Since you'll be running them on a server, maybe the final size isn't so important.

Another thing to try is to do them the way you did before, but instead of setting a fixed width, set a minimum wisth of 512. I expect it'll actually give you a 512x384 result, and you'll have to be the judge of whether or not the quality is good enough. But it should get rid of the blocking.

[kis2005]

manono, thanks I'll check out both of those. I had tried using Auto on the width but I still got blocking when played in full screen...which it will be to play it on a TV. With the newer movies I have had very little trouble except for dark movies like the Unforgiven, but all I did was to increase the size a little and it worked. Un that one i did have to change the audio to MP3 because of the low volume on Clint's movies.

[manono]

Hi-

I thought of something when I was reading your last post about already having tried lower resolutions. I was assuming that the blockiness was caused by too high of a resolution combined with too small of a file size. There's another kind of blocking that shows up in dark areas and solid colored areas, such as skies and walls. That's caused (I think) by MPEG-4 encoding in 16x16 pixel blocks. If you're viewing on an LCD monitor, it'll look even worse. Since you'll be viewing on your TV set, have you tried burning any of the encodes to disc yet to have a look on the TV? They may dramatically improve.

In any event, posting the log for one of these bad encodes may help to sort it out.

[kis2005]

manono,

I think you hit the head on the nail...the blockyness is in the darker areas and I do preview on an LCD. I'll see what it looks like on the TV though my video card (true media server is in the works, but this works just fine). Thanks for the help. I am trying McLintock again with 2GB max to see if it looks better with the 2 passes. The 65% single pass looked OK but was at 2.4GB more then I want to spend space, Like I said before it is all trial and error on some of these movies. I've done Robin Hood 1935 version and Treasure of the Seirra Madre at 1/4 DVD w/ 192 VBR and had no problem. I'll let you know what I come up with. Thanks again.

[manono]

So that 65% AVI didn't show any blocking that you could tell? Then it may be a combination of the 2 factors, low quality and LCD viewing. Bitrate starved blocks and dark blocks.

You may have to lower your resolutions to 512*xxx for some of these, if you want to keep to the 1/4 DVD size.

And you're a man after my own heart. Errol Flynn's Robin Hood and Bogie's Treasure are 2 of my all-time faves.

[kis2005]

The film quality of the old movies aren't the best, but all the actors had to be talented and the story had to be good, because there wasn't much for effects.

The movies are all FS, so with the ones that are around 1:30 I'll go with 1/4 DVD, Fixed res 640, and 160CBR. The other ones I'll try 1/3 DVD. I don't want to go to big, but I do want quality. The Road Bali and Rio do look like they were authored as well as Sierra Madre or Robin Hood. Those two were reconditioned as where the Road movies came from UCLA film archive, so I can only get what I can get. If at a later date I find myself hating the results, I'll re do them, but I think it should do OK. I'll still run them on the big screen...I didn't realize the problems I see on the LCD could be caused by it.

Thanks again.

[BigDid]

@ Manono & all, happy new year,

Blocks are (for me) really difficult to deal with specially from TV capture. It seems you are getting rid of your problem, if not consider 2 types of blocking:
- one that is already in the mpeg2 source (capture often, VOB rarely) in this case you see them in the source before compressing.
-one that comes with compression (see manono excellent suggestions for that one) in this case you don't see them in the source but in the final avi file or comptest.
My point is if adjusting size of file/bitrate or width does'nt work You'll have to tempt the big adventure of filtering. Trying to learn Gknot AND avisynth filtering at the same time may be very frustrating (I said maybe ;) ) It was the case for me and I am still looking for an alternative to Gknot. So in the meanwhile (I'm kind of lazy) I continue with AGK and AGKTweaker that can really be of good help until you need more powerful scripts. Here is the link to the thread if you need it: http://forum.doom9.org/showthread.php?t=79227
Happy encoding.

Did

[kis2005]

Just an Update: I was able to get DVD quality (as good as source) for the Road to Rio, Road to Bali by setting 1/3 rip fixed at 640 (FS source) and the audio set to 160 CBR MP3. McLintock on the other hand wasn't very good, at those settings, though I didn't see much of a difference at 2GB max, so I opted for the 1/3. The reason being is that McLintock was poor Quality to begin with, so I got as best as I could. Thanks for the help.