digitalFAQ.com Forums [Archives]

digitalFAQ.com Forums [Archives] (http://www.digitalfaq.com/archives/)
-   Video Encoding and Conversion (http://www.digitalfaq.com/archives/encode/)
-   -   FFMPEG: Does this seem correct? (http://www.digitalfaq.com/archives/encode/9196-ffmpeg-correct.html)

bigggt 04-18-2004 02:31 PM

FFMPEG: Does this seem correct?
 
Finished my first encode but

Size of movie is 89 minutes
resolution 352x240
bitrate 1145
framerate 23.976
GOP 24
dvd to kvcd(avi though)

size 1 80 minute cd

final size of video -299 mb

Also this gave a finished .mpv file instead of .m2v is this normal with the new version of Mencoder and do i just change it to .m1v

Should the video not be around 700 or so like tmpge

I have a very slow celeron 900 but i was getting 20fps ,this seems way to fast so i am wondering if it is doing everything proper

Thanx

digitall.doc 04-18-2004 04:06 PM

... and, how does it look?. If the hole film is encoded in 299 Mb, I'm afraid it will look bad.
I was about to say: "... and tell me what you get in BitrateViewer..." but it's just for m2v streams.

staigerpaip 04-19-2004 08:11 AM

The standard settings in the template files are too much for the low resolutions you are using. Mencoder is encoding the movie with the best quality possible (with your settings). It connot raise the bitrate (and quality) anymore. I had the same problems (avg. bitrate way under the asked avg.) I had already been experimenting with scplx_mask=0.1 or even 0.0. This will raise the bitrate en with low res. you will get the asked avg. bitrate. Problem with scplx_mask=0.1 and 0 is blocks on black surfaces. I think you should keep scplx_mask above 0.2 (just my observation). So I think the best thing to do is to raise the resolution and give mencoder a little work out and keep the scplx_mask the way it is in the templates.

Greets

digitall.doc 04-19-2004 10:01 AM

staigerpaip,
you're right, one possible problem is that with high quality settings as we use, mencoder could encode the film with average bitrate less than desired. That's why I asked how did it look (I'm afraid this is not bigggt problem). But in this case, it would be encoding at higher quality possible at a given resolution... is that bad?. I think no. Yes, the solution is raise the resolution, so mencoder will need more bits to encode the film.
But I don't think we're using the higher quality possible. Using trellis with cbp, or mbd=2, would be using even higher quality. I guess you refer to the fact we already use min quantizers at minimum possible. But if the whole film is encoded with quantizers=1 and average bitrate<desired... that means we can make it at a higher resolution (or add more noise,...)

bigggt 04-19-2004 06:18 PM

Thanx guys for the suggestions

@ digitall.doc

It doesn't look good but i was only testing the encoder at 352x240 for speed (having problems getting everything working),i

I do all my encodes at 528x480(when possible) its just i thought it would take it to the 700 mark.

For example i used tmpge and put the cq to 90(352x240) and got a final video size to 594 mb's for the same movie,i'm yet to put it on a cd but i imagine its a lot better.

I will try the same movie at higher resolution and see what happens.

Thanx again


All times are GMT -5. The time now is 04:00 PM  —  vBulletin © Jelsoft Enterprises Ltd

Site design, images and content © 2002-2024 The Digital FAQ, www.digitalFAQ.com
Forum Software by vBulletin · Copyright © 2024 Jelsoft Enterprises Ltd.